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CN118810546B - Discharge control method, battery management system and electricity utilization device - Google Patents

Discharge control method, battery management system and electricity utilization device Download PDF

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Publication number
CN118810546B
CN118810546B CN202411283943.XA CN202411283943A CN118810546B CN 118810546 B CN118810546 B CN 118810546B CN 202411283943 A CN202411283943 A CN 202411283943A CN 118810546 B CN118810546 B CN 118810546B
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Prior art keywords
current
sampling
voltage drop
battery pack
voltage
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CN118810546A (en
Inventor
王琳皓
甘富允
严明伟
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Contemporary Amperex Technology Co Ltd
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Contemporary Amperex Technology Co Ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
    • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
    • B60L58/12—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries responding to state of charge [SoC]
    • B60L58/14—Preventing excessive discharging
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L3/00—Electric devices on electrically-propelled vehicles for safety purposes; Monitoring operating variables, e.g. speed, deceleration or energy consumption
    • B60L3/0023—Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train
    • B60L3/0046—Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train relating to electric energy storage systems, e.g. batteries or capacitors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
    • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
    • B60L58/18—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries of two or more battery modules
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
    • G01R31/367—Software therefor, e.g. for battery testing using modelling or look-up tables
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
    • G01R31/382—Arrangements for monitoring battery or accumulator variables, e.g. SoC
    • G01R31/3842—Arrangements for monitoring battery or accumulator variables, e.g. SoC combining voltage and current measurements
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
    • G01R31/396—Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/44—Methods for charging or discharging
    • H01M10/448—End of discharge regulating measures
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0029—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0047—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with monitoring or indicating devices or circuits
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0047—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with monitoring or indicating devices or circuits
    • H02J7/0048—Detection of remaining charge capacity or state of charge [SOC]
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/007—Regulation of charging or discharging current or voltage
    • H02J7/00712—Regulation of charging or discharging current or voltage the cycle being controlled or terminated in response to electric parameters
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/007—Regulation of charging or discharging current or voltage
    • H02J7/00712—Regulation of charging or discharging current or voltage the cycle being controlled or terminated in response to electric parameters
    • H02J7/007182—Regulation of charging or discharging current or voltage the cycle being controlled or terminated in response to electric parameters in response to battery voltage
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/007—Regulation of charging or discharging current or voltage
    • H02J7/007188—Regulation of charging or discharging current or voltage the charge cycle being controlled or terminated in response to non-electric parameters
    • H02J7/007192—Regulation of charging or discharging current or voltage the charge cycle being controlled or terminated in response to non-electric parameters in response to temperature
    • H02J7/007194—Regulation of charging or discharging current or voltage the charge cycle being controlled or terminated in response to non-electric parameters in response to temperature of the battery
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2240/00—Control parameters of input or output; Target parameters
    • B60L2240/40—Drive Train control parameters
    • B60L2240/54—Drive Train control parameters related to batteries
    • B60L2240/545—Temperature
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2240/00—Control parameters of input or output; Target parameters
    • B60L2240/40—Drive Train control parameters
    • B60L2240/54—Drive Train control parameters related to batteries
    • B60L2240/547—Voltage
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Transportation (AREA)
  • Sustainable Energy (AREA)
  • Sustainable Development (AREA)
  • Manufacturing & Machinery (AREA)
  • General Chemical & Material Sciences (AREA)
  • Electrochemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Chemical & Material Sciences (AREA)
  • Secondary Cells (AREA)

Abstract

本申请公开了一种放电控制方法、电池管理系统及用电装置，涉及电池技术领域，在确定未来时刻最小电池单体的预测电压时，考虑到电池包在使用过程中由于累积极化所引起的压降，使得预测电压更加贴近电池包未来时刻的极化状态，因此，本申请实施例中放电控制方法根据预测电压能够提前预知未来时刻电池包是否存在欠压风险，从而提前控制电池包的许用放电电流和/或许用放电功率，进而预防电池欠压，提高电池包的安全性能。

The present application discloses a discharge control method, a battery management system and an electrical device, which relate to the field of battery technology. When determining the predicted voltage of the smallest battery cell at a future moment, the voltage drop caused by the cumulative polarization of the battery pack during use is taken into account, so that the predicted voltage is closer to the polarization state of the battery pack at a future moment. Therefore, the discharge control method in the embodiment of the present application can predict in advance whether the battery pack will have an undervoltage risk at a future moment based on the predicted voltage, thereby controlling the allowable discharge current and/or allowable discharge power of the battery pack in advance, thereby preventing battery undervoltage and improving the safety performance of the battery pack.

Description

Discharge control method, battery management system and electricity utilization device
Technical Field
The present application relates to the field of battery technologies, and in particular, to a discharge control method, a battery management system, and an electric device.
Background
The popularization of electric vehicles makes the stability of the power battery during discharging particularly important, and particularly, the under-voltage fault is avoided. When the vehicle is rapidly accelerated or decelerated, the battery is easy to generate polarization, so that the voltage of the battery is rapidly reduced, and even under-voltage conditions can be triggered.
In order to effectively solve the problem of under-voltage of a power battery, the current method is that a battery management system monitors the voltage of the minimum battery unit in real time, and the battery management system limits allowable discharge power and/or allowable discharge current according to the voltage of the minimum battery unit to ensure that the battery operates in a safe voltage range, so that the under-voltage of the battery is prevented, and the safe running of an electric automobile is ensured.
However, the method of limiting the allowable discharge power and/or the allowable discharge current according to the voltage of the minimum battery cell cannot predict the risk of the under-voltage at the future time in advance, and the under-voltage prevention effect is not good.
Disclosure of Invention
The application mainly aims to provide a discharge control method, a battery management system and an electricity utilization device, and aims to provide a discharge control method with higher accuracy, which can predict the undervoltage risk at the future moment in advance according to the predicted voltage and prevent the undervoltage problem of a battery in advance.
In order to achieve the above object, the present application provides a discharge control method, the method comprising:
The method comprises the steps of obtaining the residual capacity, the temperature and the actual voltage of a minimum battery cell at the current sampling moment, obtaining the actual current and the allowable discharge current of a battery pack at the current sampling moment, wherein the minimum battery cell is the battery cell with the minimum residual capacity among a plurality of battery cells of the battery pack, according to the residual capacity and the temperature of the minimum battery cell at the current sampling moment, the actual current and the allowable discharge current of the battery pack at the current sampling moment and at least one of the actual voltages of the minimum battery cell at N sampling moments before the current sampling moment and the current sampling moment, predicting the voltage drop of the battery pack at the future moment due to accumulated polarization, determining the predicted voltage of the minimum battery cell at the future moment according to the actual voltage and the voltage drop at the current sampling moment, and controlling the allowable discharge current and/or the allowable discharge power of the battery pack according to the predicted voltage.
In an embodiment, the voltage drop caused by the accumulated polarization of the battery pack comprises a first voltage drop caused by ohmic polarization of the battery pack and a second voltage drop caused by concentration polarization and electrochemical polarization of the battery pack, the first voltage drop caused by ohmic polarization of the battery pack at a future time is predicted according to the residual capacity and the temperature of the minimum battery cell at the current sampling time, the actual current and the allowable discharge current of the battery pack at the current sampling time and at least one of the actual voltages of the minimum battery cell at N sampling times before the current sampling time and the current sampling time, and the voltage drop caused by the accumulated polarization of the battery pack at a future time is predicted according to the residual capacity and the temperature of the minimum battery cell at the current sampling time, the actual current and the allowable discharge current of the battery pack at the current sampling time, and the first voltage drop caused by ohmic polarization of the battery pack at the future time is predicted according to the current sampling time and the actual voltage of the minimum battery cell at the N sampling times before the current sampling time and the current sampling time.
In this embodiment, for the voltage drop caused by polarization with different properties, different calculation modes are adopted to calculate, so that the accuracy of predicting the voltage drop caused by accumulated polarization is further improved.
In an embodiment, the predicting the first voltage drop of the battery pack due to ohmic polarization at the future time according to the residual capacity and temperature of the minimum battery cell at the current sampling time, the actual current and allowable discharge current of the battery pack, and the allowable discharge current of the battery pack at the current sampling time comprise determining the ohmic impedance of the battery pack at the current sampling time according to the residual capacity and temperature of the minimum battery cell at the current sampling time, and predicting the first voltage drop of the battery pack due to ohmic polarization at the future time according to the actual current and allowable discharge current of the battery pack at the current sampling time and the ohmic impedance.
In the embodiment, the first voltage drop caused by ohmic polarization after the current rise at the future time is predicted by presetting the current rise of the battery pack from the actual current at the current sampling time to the allowable discharge current at the future time, so that the accuracy of predicting the first voltage drop at the future time is improved.
In an embodiment, the predicting the second voltage drop of the battery pack due to concentration polarization and electrochemical polarization at the future time according to the current sampling time and the actual voltage of the minimum battery cell at the N sampling times before the current sampling time comprises determining a weighted average historical voltage drop of N sampling periods before the current sampling time according to the current sampling time and the actual voltage of the minimum battery cell at the N sampling times before the current sampling time, and predicting the second voltage drop of the battery pack due to concentration polarization and electrochemical polarization at the future time according to the weighted average historical voltage drop of N sampling periods before the current sampling time.
In this embodiment, the historical pressure drop can be understood as the pressure drop caused by concentration polarization and electrochemical polarization, so that the weighted average historical pressure drop of N sampling periods before the current sampling time is calculated to predict the second pressure drop caused by concentration polarization and electrochemical polarization of the battery pack at the future time, and the accuracy of predicting the second pressure drop at the future time is improved.
In an embodiment, the determining the weighted average historical voltage drop of the N sampling periods before the current sampling time according to the current sampling time and the actual voltages of the minimum battery cells at the N sampling times before the current sampling time includes determining a trend of change of the voltage drop rate of the minimum battery cells in the N sampling periods according to the current sampling time and the actual voltages of the minimum battery cells at the N sampling times before the current sampling time, and determining the weighted average historical voltage drop of the N sampling periods before the current sampling time according to the trend of change of the voltage drop rate of the minimum battery cells in the N sampling periods and a calculation mode of weighted average historical voltage drops corresponding to the trend of change.
In this embodiment, the current charge and discharge scenario of the battery pack is distinguished by the variation trend of the voltage drop rate of the minimum battery cell in the N sampling periods, and the weighted average historical voltage drops corresponding to different charge and discharge scenarios are determined according to the calculation mode of the weighted average historical voltage drops corresponding to the variation trend, so that the prediction result is more accurate.
In addition, in order to achieve the above purpose, the application further provides a battery management system, which comprises a sampling circuit, a controller and a controller, wherein the sampling circuit is used for acquiring the residual capacity, the temperature and the actual voltage of a minimum battery cell at the current sampling moment and acquiring the actual current and the allowable discharge current of a battery pack at the current sampling moment, the minimum battery cell is the battery cell with the minimum residual capacity among a plurality of battery cells of the battery pack, the controller is used for controlling the actual current and the allowable discharge current of the battery pack at the current sampling moment according to the residual capacity and the temperature of the minimum battery cell at the current sampling moment and at least one of the actual voltages of the minimum battery cell at N sampling moments before the current sampling moment and the current sampling moment, predicting the voltage drop of the battery pack caused by accumulated polarization at the future moment, and determining the predicted voltage of the minimum battery cell at the future moment according to the actual voltage and the voltage drop at the current sampling moment, and controlling the allowable discharge current and/or allowable discharge power of the battery pack according to the predicted voltage.
In addition, in order to achieve the above object, the present application also proposes an electric device including the battery management system in the above embodiment.
One or more technical schemes provided by the application have at least the following technical effects:
According to at least one of the residual capacity and the temperature of the minimum battery cell at the current sampling time, the actual current and the allowable discharge current of the battery pack and the actual voltage of the minimum battery cell at N sampling times before the current sampling time, the voltage drop of the battery pack at the future time due to accumulated polarization is predicted, and the predicted voltage of the minimum battery cell at the future time is determined by combining the voltage drop of the battery pack at the future time due to accumulated polarization and the actual voltage of the minimum battery cell at the current sampling time. Because the battery pack has accumulated polarization in the use process, and the accumulated polarization is a main factor causing the voltage drop of the battery, in the embodiment, when the predicted voltage of the minimum battery cell at the future moment is determined, the predicted voltage is more close to the polarization state of the battery pack at the future moment due to the voltage drop caused by the accumulated polarization in the use process of the battery pack, so that the discharging control method in the embodiment of the application can predict whether the battery pack at the future moment has the under-voltage risk in advance according to the predicted voltage, thereby controlling the allowable discharging current and/or the allowable discharging power of the battery pack in advance, further preventing the under-voltage of the battery and improving the safety performance of the battery pack.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description, serve to explain the principles of the application.
In order to more clearly illustrate the embodiments of the application or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, and it will be obvious to a person skilled in the art that other drawings can be obtained from these drawings without inventive effort.
FIG. 1 is a schematic flow chart of a discharge control method according to an embodiment of the present application;
FIG. 2 is a schematic flow chart of a discharge control method according to a second embodiment of the present application;
FIG. 3 is a schematic flow chart of a discharge control method according to a third embodiment of the present application;
FIG. 4 is a schematic flow chart of a fourth embodiment of a discharge control method according to the present application;
FIG. 5 is a schematic flow chart of a fifth embodiment of a discharge control method according to the present application;
FIG. 6 is a graph showing a first voltage trend within N sampling periods of the battery pack according to the present application;
FIG. 7 is a graph showing a second voltage trend within N sampling periods of the battery pack according to the present application;
FIG. 8 is a graph showing a third voltage variation trend within N sampling periods of the battery pack according to the present application;
FIG. 9 is a graph showing a fourth voltage trend within N sampling periods of the battery pack according to the present application;
Fig. 10 is a schematic block diagram of a battery management system according to an embodiment of the application.
The achievement of the objects, functional features and advantages of the present application will be further described with reference to the accompanying drawings, in conjunction with the embodiments.
Detailed Description
It should be understood that the specific embodiments described herein are merely illustrative of the technical solution of the present application and are not intended to limit the present application.
In order to facilitate understanding of the technical solutions of the embodiments of the present application, some terms related to the embodiments of the present application are briefly described below.
1. Battery cell
The battery cell is the most basic unit of a battery, which is the smallest independent electric energy storage unit in a battery system, and consists of a positive electrode, a negative electrode, an electrolyte and a separator, and can store and release electric energy through chemical reaction. The battery cells have minimum capacity and voltage, and it is generally necessary for a plurality of battery cells to be connected in series or in parallel to form a battery module.
2. Battery module
The battery module is generally formed by combining a plurality of battery cells in a serial-parallel connection manner. In some examples, the Battery module further includes components such as a Battery management system (Battery MANAGEMENT SYSTEM, BMS), a thermal management system (THERMAL MANAGEMENT SYSTEM, TMS), connectors, a housing, and the like. The battery module may provide higher voltage and capacity than the battery cells, and is generally used in electric vehicles, energy storage systems, and the like. It is noted that the battery module may include at least one battery cell.
3. Battery pack
The battery pack is formed by combining a plurality of battery modules in a serial-parallel connection mode. In some examples, the battery pack also includes the necessary electrical connections, battery management systems, thermal management systems, and other protective components, among others. The battery pack can provide higher voltage and capacity, and is a final assembly form of battery systems of electric automobiles, energy storage systems and the like.
4. Residual electric quantity
The State Of Charge (SOC) is the ratio Of the amount Of available power in the battery to the nominal capacity. For each cell in the battery pack, there is a corresponding SOC that indicates the state of charge of the cell. For the entire battery pack, there is also a corresponding total SOC that indicates the state of charge of the battery pack.
5. Cumulative polarization
The accumulated polarization refers to a phenomenon in which charges are accumulated inside the battery during charge and discharge of the battery due to electrochemical reactions of electrode materials, electrolyte, and an electrode surface solid electrolyte interface film. This charge accumulation causes a drop in the internal voltage, which results in a drop in the terminal voltage of the battery. The voltage drop caused by the accumulated polarization is a comprehensive concept including the voltage drop of the battery during charge and discharge due to various reasons. These reasons can be divided into several main types:
(1) Ohmic polarization
Voltage drop due to internal resistance of the battery (including contact resistance of electrode material, electrolyte, separator and electrode to electrolyte interface). This voltage drop is instantaneous and once the current ceases, the ohmic polarization disappears.
(2) Concentration polarization
Voltage drop due to non-uniform ion concentration inside the battery. During charge and discharge, the concentration difference of lithium ions between the surface and the interior of the electrode causes charge imbalance on the surface of the electrode.
(3) Electrochemical polarization
The voltage drop due to the electrochemical reaction rate is not followed by the current change. This involves charge transfer reactions at the electrode surface and deposition of material at the electrode surface.
The "accumulation" in the accumulated polarization means that these polarization phenomena are gradually accumulated during repeated charge and discharge of the battery, resulting in gradual degradation of the battery performance. When referring to the voltage drop caused by cumulative polarization, it generally includes voltage drops caused by ohmic impedance, as well as voltage drops caused by concentration polarization and electrochemical polarization. The cumulative effects of these voltage drops can affect the overall performance of the battery, including reduced capacity, reduced efficiency, and reduced life.
6. Allowable discharge current
The allowable discharge current refers to the maximum discharge current that the battery pack can safely withstand, and exceeding this current value may adversely affect the performance and life of the battery pack. The allowable discharge current is typically determined by the battery manufacturer based on the design and test results of the battery and is provided in the battery's technical specifications.
7. Allowable discharge power
The allowable discharge power refers to the maximum discharge power allowed by the battery under specific conditions, and this power value is determined by the battery manufacturer according to the design and performance test of the battery. The allowable discharge power is critical to the safe use and performance of the battery.
8. Under-voltage
The "under-voltage" means that the voltage of the battery cells or the battery modules in the battery pack drops below a specific threshold of its normal operating voltage during the discharging process. For lithium ion batteries, there is a minimum operating voltage limit for each cell, and if the cell voltage falls below this limit during discharge, an under-voltage is considered to occur.
The undervoltage phenomenon may lead to the following problems:
(1) The battery performance is reduced, and the performance of the battery is damaged by long-term under-voltage operation, so that the cycle life of the battery is reduced. (2) Battery damage-severe under-voltage may cause irreversible changes in the internal chemistry of the battery, resulting in battery damage and even failure. (3) Safety risks lithium batteries may be safe to operate in under-voltage conditions, such as internal short circuits or leaks.
In a battery management system, the pre-undervoltage threshold is a predetermined protection voltage value that is generally above the minimum operating voltage limit of the battery cell. When the voltage of the battery cell drops to the pre-undervoltage threshold, the battery management system takes measures to limit the discharge current or power so as to prevent the voltage of the battery cell from further dropping to the undervoltage state. The setting of the pre-undervoltage threshold value needs to comprehensively consider factors such as the type, specification, use condition, safety requirement, performance target and the like of the battery.
For a better understanding of the technical solution of the present application, the following detailed description will be given with reference to the drawings and the specific embodiments.
The popularization of electric vehicles makes the stability of the power battery during discharging particularly important, and particularly, the under-voltage fault is avoided. When the vehicle is rapidly accelerated or decelerated, the battery is easy to generate polarization, so that the voltage of the battery is rapidly reduced, and even under-voltage conditions can be triggered.
In order to ensure the running safety of the vehicle, various properties of the power battery need to be monitored. One useful property is battery terminal voltage. The battery terminal voltage may be used to delineate the allowable charge cut-off voltage and discharge cut-off voltage to provide information for determining the usage boundaries of the power battery and preventing over-discharge of the battery from occurring.
The prior method is that a battery management system monitors the voltage of the minimum battery unit in real time, and the battery management system limits allowable discharge power and/or allowable discharge current according to the voltage of the minimum battery unit, so as to ensure that the battery operates in a safe voltage range, thereby preventing the battery from being under-voltage and ensuring the safe running of the electric automobile.
However, the method of limiting the allowable discharge power and/or the allowable discharge current according to the voltage of the minimum battery cell cannot predict the risk of the under-voltage at the future time in advance, and the under-voltage prevention effect is not good.
Aiming at the problem, the embodiment of the application provides a discharge control method, which comprises the steps of firstly obtaining the residual capacity, the temperature and the actual voltage of a minimum battery cell at the current sampling time, obtaining the actual current and the allowable discharge current of a battery pack at the current sampling time, wherein the minimum battery cell is the battery cell with the minimum residual capacity in a plurality of battery cells of the battery pack, secondly, according to the residual capacity, the temperature, the actual current and the allowable discharge current of the minimum battery cell at the current sampling time, and at least one of the actual voltages of the minimum battery cell at the current sampling time and N sampling times before the current sampling time, predicting the voltage drop of the battery pack at the future time due to accumulated polarization, and finally, according to the actual voltage and the voltage drop at the current sampling time, determining the predicted voltage of the minimum battery cell at the future time.
Because the battery pack has accumulated polarization in the use process, and the accumulated polarization is a main factor causing the voltage drop of the battery, in the embodiment, when the predicted voltage of the minimum battery cell at the future moment is determined, the predicted voltage is more close to the polarization state of the battery pack at the future moment due to the voltage drop caused by the accumulated polarization in the use process of the battery pack, so that the discharging control method in the embodiment of the application can predict whether the battery pack at the future moment has the under-voltage risk in advance according to the predicted voltage, thereby controlling the allowable discharging current and/or the allowable discharging power of the battery pack in advance, further preventing the under-voltage of the battery and improving the safety performance of the battery pack.
It should be noted that the execution body of the present embodiment may be a device having a data acquisition function, a data processing function, and a program running function, for example, a battery management system, or an electric vehicle, an electric bicycle, or the like including the battery management system.
The present embodiment and the following embodiments will be described below with reference to a battery management system as an example.
Based on the foregoing, an embodiment of the present application provides a discharge control method, and referring to fig. 1, fig. 1 is a schematic flow chart of a first embodiment of the discharge control method of the present application.
In this embodiment, the discharge control method includes steps S10 to S40:
step S10, obtaining the residual capacity, the temperature and the actual voltage of the minimum battery cell at the current sampling moment, and obtaining the actual current and the allowable discharge current of the battery pack at the current sampling moment.
The battery management system may set a fixed sampling period to obtain the relevant data of the battery pack, and sampling is performed every other sampling period. For example, the sampling period may be set to 100 milliseconds, with sampling every 100 milliseconds. Alternatively, the battery management system may set a fixed sampling time, for example, 0 ms, 50 ms, 80 ms, etc., and acquire the relevant data of the battery pack according to the fixed sampling time.
For each sampling time, the battery management system acquires the residual quantity SOC, the temperature T and the actual voltage Vmin of the minimum battery cell at the current sampling time, and acquires the actual current I and the allowable discharge current Ip of the whole battery pack at the current sampling time. The minimum battery cell is the battery cell with the least residual electric quantity in the battery cells of the battery pack.
The battery management system is internally provided with a permitted discharge ammeter in advance, wherein the permitted discharge ammeter comprises permitted discharge currents corresponding to a battery pack when the minimum battery cells in the battery pack are at different temperatures and different residual electric quantities. And according to the residual electric quantity and the temperature of the minimum battery cell at the current sampling moment, the allowable discharge current Ip of the minimum battery cell corresponding to the current sampling moment can be obtained by inquiring an allowable discharge ammeter in a linear difference value table look-up mode.
Step S20, predicting the voltage drop of the battery pack at the future time due to accumulated polarization according to the residual capacity and temperature of the minimum battery cell at the current sampling time, the actual current and allowable discharge current of the battery pack, and the actual voltages of the minimum battery cell at the current sampling time and N sampling times before the current sampling time.
During use of the battery pack, the internal charge of the battery accumulates due to the electrochemical reaction, i.e., there is an accumulated polarization of the battery. Due to the polarization phenomenon, the battery voltage may be reduced. Therefore, in the present embodiment, when determining the predicted voltage of the smallest battery cell at the future time, the voltage drop of the battery pack caused by the accumulated polarization during use needs to be considered. Based on this, in this step, the voltage drop of the battery pack due to the accumulated polarization at the future time is predicted according to the remaining power and temperature of the minimum battery cell at the current sampling time, the actual current and allowable discharge current of the battery pack, and the actual voltages of the minimum battery cells at the current sampling time and N sampling times before the current sampling time.
Step S30, according to the actual voltage and the voltage drop at the current sampling time, determining the predicted voltage of the minimum battery cell at the future time.
Step S40, the allowable discharge current and/or the allowable discharge power of the battery pack are controlled according to the predicted voltage.
Specifically, for the above-described step S30 and step S40, the voltage Vp of the minimum cell at the future time can be calculated by the following equation (1):
Vp=Vmin-∆V(1)
where Vmin is the actual voltage of the smallest cell at the current sampling time and fatin V is the voltage drop due to accumulated polarization at the future time.
In this embodiment, when determining the predicted voltage of the minimum battery cell at the future time, the predicted voltage is closer to the polarization state of the battery pack at the future time due to the voltage drop caused by the accumulated polarization in the use process of the battery pack, so that the discharging control method in the embodiment of the application can predict whether the battery pack at the future time has an under-voltage risk in advance according to the predicted voltage, thereby controlling the allowable discharging current and/or the allowable discharging power of the battery pack in advance and further preventing the under-voltage of the battery.
Next, it is explained how to predict the voltage drop of the battery pack due to the accumulated polarization at a future time.
The accumulated polarization of the battery includes ohmic polarization, concentration polarization and electrochemical polarization, and all three polarization phenomena of the battery lead to voltage drop of the battery, so that in the embodiment, when the voltage drop caused by the accumulated polarization of the battery pack at the future moment is predicted, the voltage drop caused by the three polarization relations needs to be predicted. Referring specifically to fig. 2, fig. 2 is a schematic flow chart of a discharge control method according to a second embodiment of the present application. Step S20 in the first embodiment includes step S201 and step S202.
Step S201, predicting a first voltage drop of the battery pack due to ohmic polarization at a future time according to the remaining power, temperature, actual current and allowable discharge current of the minimum battery cell at the current sampling time.
Since the voltage drop caused by ohmic polarization is related to the variation of the current, in this embodiment, the first voltage drop caused by ohmic polarization of the battery pack at the future time is predicted according to the actual current, allowable discharge current, the residual capacity of the minimum cell, and the temperature of the battery pack at the current sampling time.
Step S202, predicting a second voltage drop of the battery pack at a future time due to concentration polarization and electrochemical polarization according to the current sampling time and the actual voltage of the minimum battery cell at N sampling times before the current sampling time.
Since the ohmic polarization is instantaneous, it disappears once the current stops changing. And the battery pack has small current variation in the stable discharge stage, so that ohmic polarization caused by current variation is negligible. The concentration polarization and the electrochemical polarization are gradually accumulated in the repeated discharging process of the battery, so that in the embodiment, the second voltage drop of the battery pack at the future time due to the concentration polarization and the electrochemical polarization can be predicted according to the historical data of the actual voltage of the minimum battery cell, namely, the current sampling time and the actual voltage of the minimum battery cell at N sampling times before the current sampling time, so that the predicted second voltage drop is more fit with the states of the concentration polarization and the electrochemical polarization at the future time of the battery, and the predicted second voltage drop is more accurate.
In this embodiment, since the ohmic polarization is instantaneous and the concentration polarization and the electrochemical polarization are gradually accumulated, the first voltage drop of the battery pack at the future time due to the ohmic polarization is predicted according to the residual capacity and the temperature of the minimum battery cell at the current sampling time, the actual current of the battery pack and the allowable discharge current, and the second voltage drop of the battery pack at the future time due to the concentration polarization and the electrochemical polarization is predicted according to the actual voltages of the minimum battery cell at the current sampling time and N sampling times before the current sampling time, wherein the sum of the first voltage drop and the second voltage drop is the voltage drop of the battery pack at the future time due to the accumulated polarization. That is, for the voltage drop caused by polarization with different properties, different calculation modes are adopted to calculate, so that the accuracy of predicting the voltage drop caused by accumulated polarization is further improved.
A description will be given below of how to predict the first voltage drop of the battery pack due to ohmic polarization at a future time.
In one possible implementation, referring to fig. 3, fig. 3 is a schematic flow chart of a third embodiment of the discharge control method of the present application. Step S201 in the second embodiment includes step S2011 and step S2012.
And step 2011, determining the ohmic impedance of the battery pack according to the residual electric quantity and the temperature of the minimum battery cell at the current sampling time.
The battery management system is internally provided with a battery ohm impedance meter in advance, and the battery ohm impedance meter comprises the ohm impedance actually measured by the minimum battery monomer at different temperatures and different residual electric quantities. According to the residual electric quantity and the temperature of the minimum battery cell at the current sampling moment, the ohmic impedance meter of the battery can be queried in a linear interpolation table look-up mode to obtain the ohmic impedance R0 of the minimum battery cell corresponding to the current sampling moment.
Step 2012, predicting a first voltage drop of the battery pack due to ohmic polarization at a future time according to the actual current, allowable discharge current and ohmic impedance of the battery pack at the current sampling time.
In this embodiment, the actual current of the battery pack is signed, the actual current is positive, which indicates that the battery pack is discharging, and the actual current is negative, which indicates that the battery pack is recharging. The recharging of the battery pack refers to the process of recovering energy and storing the energy in the battery through an energy recovery mechanism in the using process of the battery pack. The recharging of the battery pack electric quantity is different from the recharging of the battery pack, the recharging of the battery pack needs an external power supply, and the recharging of the battery pack electric quantity does not need the external power supply.
Whether the battery pack is discharging or recharging, the first voltage drop, fatv 1, due to ohmic polarization, R0, at a future time can be calculated by the following equation (2):
∆V1=(Ip-I)*R0(2)
Wherein Ip is the allowable discharge current of the battery pack at the current sampling time, I is the actual current of the battery pack at the current sampling time, and R0 is the ohmic impedance of the battery pack at the current sampling time. In the case of a controlled discharge, I is less than or equal to Ip.
In this embodiment, the first voltage drop caused by ohmic polarization after the current rise at the future time is predicted by presetting the current rise of the battery pack from the actual current I at the current sampling time to the allowable discharge current Ip at the future time, so that the accuracy of predicting the first voltage drop at the future time is improved.
A description will be given below of how to determine the second pressure drop due to concentration polarization and electrochemical polarization at a future time.
In one possible implementation, the second voltage drop of the future time cell pack due to concentration polarization and electrochemical polarization may be predicted by calculating a weighted average historical voltage drop N sample periods before the current sample time. Referring to fig. 4, fig. 4 is a flowchart illustrating a discharge control method according to a fourth embodiment of the present application. Step S202 in the second embodiment includes step S2021 and step S2022.
Step S2021, determining a weighted average historical voltage drop of N sampling periods before the current sampling time according to the current sampling time and the actual voltage of the minimum cell at N sampling times before the current sampling time.
In this embodiment, the actual voltage of the minimum battery cell at the current sampling time and the actual voltages of the minimum battery cells at the N sampling times before the current sampling time add up to the actual voltages of the minimum battery cells at n+1 sampling times. And taking two adjacent sampling moments as a sampling period, calculating the voltage drop of the minimum battery cell of the N sampling periods according to the actual voltage of the minimum battery cell of the N+1 sampling moments, and calculating the weighted average historical voltage drop of the N sampling periods according to the voltage drop of the minimum battery cell of the N sampling periods, wherein the weighted average historical voltage drop is used for representing the voltage of the minimum battery cell, which is possibly reduced in one sampling period.
Step S2022 predicts a second voltage drop of the battery pack at the future time due to concentration polarization and electrochemical polarization based on the weighted average historical voltage drop N sampling periods prior to the current sampling time.
The "future time" is assumed to be a time after a preset time period from the current sampling time, and assuming that the preset time period is fatt 1 and the weighted average historical pressure drop of N sampling periods before the current sampling time is dV, the second pressure drop caused by concentration polarization and electrochemical polarization at the future time may be that the weighted average historical pressure drop is dV multiplied by the preset time period fatt 1, that is v2=dv×× t1.
In this embodiment, the historical pressure drop can be understood as the pressure drop caused by concentration polarization and electrochemical polarization, so that the weighted average historical pressure drop of N sampling periods before the current sampling time is calculated to predict the second pressure drop caused by concentration polarization and electrochemical polarization of the battery pack at the future time, and the accuracy of predicting the second pressure drop at the future time is improved.
The battery polarization is serious in a high-current discharge scene, so that the voltage drop rate is high, and the battery polarization is light in a low-current discharge scene, so that the voltage drop rate is low. Therefore, in order to accurately predict the second voltage drop of the battery pack caused by concentration polarization and electrochemical polarization at the future time, the current charge-discharge scene of the battery pack needs to be considered, and the calculation mode of the corresponding second voltage drop is determined according to the current charge-discharge scene of the battery pack.
In this embodiment, the current charge and discharge scenario of the battery pack is distinguished by the variation trend of the voltage drop rate of the minimum battery cell in the N sampling periods, and the weighted average historical voltage drops corresponding to different charge and discharge scenarios are determined according to the calculation mode of the weighted average historical voltage drops corresponding to the variation trend, so that the prediction result is more accurate. Referring to fig. 5, fig. 5 is a flowchart illustrating a fifth embodiment of a discharge control method according to the present application. Step S2021 in the fourth embodiment includes steps S2021-1 to S2021-2.
Step S2021-1, determining the variation trend of the voltage drop rate of the minimum battery unit in the N sampling periods according to the current sampling time and the actual voltages of the minimum battery unit in the N sampling times before the current sampling time.
In one implementation, the voltage drop of each of the N sampling periods before the current sampling time can be calculated from the current sampling time and the actual voltage of the smallest cell of the N sampling times before the previous sampling time. Assuming that the current sampling time is t10, the actual voltage of the corresponding minimum battery cell is vmin_10, and the times before the sampling time are t9, t8, t7 and t6, the voltage drop corresponding to one sampling period, i.e. the actual voltage of the minimum battery cell corresponding to the time t9 is vmin_9 and t 9-t 10, is vmin_10-vmin_9.
The voltage drop of each sampling period is divided by the duration of each sampling period to obtain the voltage drop rate in the sampling period, so that the voltage drop rate of the minimum battery cell in the N sampling periods and the change trend of the voltage drop rate of the minimum battery cell in the N sampling periods can be calculated according to the voltage drop of each sampling period in the N sampling periods before the current sampling time.
In another implementation manner, the actual voltage of the minimum battery cell at the current sampling time and N sampling times before the previous sampling time can be displayed in a coordinate system with the time on the horizontal axis and the voltage on the vertical axis, a change curve of the actual voltage of the minimum battery cell is obtained through fitting and other modes, and the change trend of the voltage dropping rate of the minimum battery cell is determined according to the change curve of the actual voltage of the minimum battery cell.
Step S2021-2, determining the weighted average historical voltage drop of N sampling periods before the current sampling time according to the variation trend of the voltage drop rate of the minimum battery cell in the N sampling periods and the calculation mode of the weighted average historical voltage drop corresponding to the variation trend.
Under the high-current discharge scene, the battery polarization condition is serious, the voltage drop rate is faster, and under the low-current discharge scene, the battery polarization condition is lighter, and the voltage drop rate is slower. The discharging scene of the battery pack in the N sampling periods can be judged according to the variation trend of the voltage dropping rate of the minimum battery unit in the N sampling periods. For example, a voltage drop rate in the first few sample periods being greater than a voltage drop rate in the last few sample periods indicates that the battery pack is discharged with a high current and then with a low current, whereas a voltage drop rate in the first few sample periods being less than a voltage drop rate in the last few sample periods indicates that the battery pack is discharged with a low current and then with a high current.
The scene of battery pack discharge can comprise (1) continuous heavy current discharge, (2) continuous light current discharge, (3) first heavy current discharge and then light current discharge, (4) first light current discharge and then heavy current discharge, (5) first heavy current discharge, continuous heavy current discharge after recharging the battery, (6) first light current discharge, continuous light current discharge after recharging the battery, (7) first heavy current discharge, second light current discharge after recharging the battery, and (8) first light current discharge, and second heavy current discharge after recharging the battery.
Because the battery polarization is serious in a heavy current discharge scene, if the battery is discharged with a heavy current and then discharged with a small current, the voltage drop generated in the heavy current discharge stage needs to be considered when determining the weighted average historical voltage drop corresponding to the discharge scene. If the battery is discharged with small current and then with large current, the voltage drop generated in the small current discharging stage can be ignored when the weighted average historical voltage drop corresponding to the discharging scene is determined, and the weighted average historical voltage drop corresponding to the discharging scene can be calculated directly according to the voltage drop generated in the large current discharging stage.
Based on the above considerations, the trend of the voltage drop rate corresponding to the above-mentioned 8 battery pack discharging scenarios can be classified into two categories:
(1) If the change trend is that the voltage dropping rate of the minimum battery cell in the continuous p1 sampling periods is larger than the voltage dropping rate of the minimum battery cell in the continuous q1 sampling periods in the N sampling periods, wherein the sum of p1 and q1 is smaller than or equal to N, and the continuous p1 sampling periods are positioned before the continuous q1 sampling periods.
That is, the battery pack is discharged with a large current in the first p1 sampling periods and discharged with a small current in the last q1 sampling periods, and if the sum of p1 and q1 is smaller than N, there may be a case that the battery is recharged. The battery polarization is serious in a high-current discharge scene, and is lighter in a low-current discharge scene. Therefore, the weight value a of the voltage drop corresponding to the first p1 sampling periods can be set to be larger, and the weight value b of the voltage drop corresponding to the last q1 sampling periods is set to be smaller, i.e. a is greater than or equal to b.
The weighted average historical pressure drop dV for N sample periods can be expressed by the following equation (3):
dV=dV1*a+dV2*b(3)
wherein dV1 is a first average historical pressure drop in p1 continuous sampling periods, dV2 is a second average historical pressure drop in q1 continuous sampling periods, a is a weight value of the first average historical pressure drop, b is a weight value of the second average historical pressure drop, the sum of a and b is 1, and a is greater than or equal to b.
As shown in fig. 6, the voltage drop rate of the minimum battery cell in p2 consecutive sampling periods is greater than the voltage drop rate of the minimum battery cell in q2 consecutive sampling periods, and p2+q2=n, i.e. the battery is in a small current discharge scenario after a large current discharge. Since the cumulative polarization of the high-current discharge phase is greater than that of the low-current discharge phase, the weight value a of the first average historical voltage drop dV1 in the consecutive p1 sampling periods is greater than or equal to the weight value b of the second average historical voltage drop in the consecutive q1 sampling periods, and the sum of a and b is 1. Then the weighted average historical voltage drop dv=dv1×a+dv2×b for N sampling periods.
Referring to fig. 7, the voltage drop rate of the minimum cell in the consecutive p2 sampling periods is greater than the voltage drop rate of the minimum cell in the consecutive q2 sampling periods, and p2+q2< N, that is, the battery is in a heavy-current discharge-after-recharge-to-light-current discharge scenario, since the cumulative polarization of the heavy-current discharge phase is greater than the cumulative polarization of the light-current discharge phase, the weight value a of the first average historical voltage drop dV1 in the consecutive p1 sampling periods is greater than or equal to the weight value b of the second average historical voltage drop in the consecutive q1 sampling periods, and the sum of a and b is 1. Then the weighted average historical voltage drop dv=dv1×a+dv2×b for N sampling periods.
(2) If the change trend is that the voltage dropping rate of the minimum battery cell in the continuous p2 sampling periods is smaller than or equal to the voltage dropping rate of the minimum battery cell in the continuous q2 sampling periods in the N sampling periods, wherein the sum of p2 and q2 is smaller than or equal to N, and the continuous p2 sampling periods are positioned before the continuous q2 sampling periods.
That is, the battery pack is discharged with a small current in the first p2 sampling periods and discharged with a large current in the last q2 sampling periods, and if the sum of p1 and q1 is smaller than N, there may be a case that the battery is recharged. The battery polarization is serious in a high-current discharge scene, and is lighter in a low-current discharge scene. Therefore, the voltage drop caused in the first p2 sampling periods can be ignored, and the weight value of the voltage drop corresponding to the last q2 sampling periods is set to be 1.
The weighted average historical pressure drop dV for N sample periods can be expressed by the following equation (4):
dV=dV3(4)
where dV3 is the third average historical pressure drop over consecutive q2 sample periods.
Referring to fig. 8, the voltage drop rate of the smallest cell in consecutive p2 sampling periods is equal to the voltage drop rate of the smallest cell in consecutive q2 sampling periods, i.e., the battery is in a continuous high current or continuous low current discharge scenario, and the cumulative polarization can be considered continuous, at which time the weighted average historical voltage drop dv=the third average historical voltage drop in consecutive q2 sampling periods. Wherein the dashed line in fig. 8 is used to represent the boundary of p2 sampling periods and q2 sampling periods.
Referring to fig. 9, the voltage drop rate of the minimum cell in the consecutive p2 sampling periods is smaller than the voltage drop rate of the minimum cell in the consecutive q2 sampling periods, that is, the battery is in a scenario of discharging a small current followed by discharging a large current, at which time the weighted average historical voltage drop dv=the third average historical voltage drop in the consecutive q2 sampling periods.
In one implementation, controlling the allowable discharge current and/or the allowable discharge power of the battery pack according to the predicted voltage includes controlling the allowable discharge current and/or the allowable discharge power of the battery pack according to a preset control strategy if the predicted voltage is less than a pre-undervoltage threshold.
The battery management system may compare the predicted voltage with a pre-under-voltage threshold by determining a predicted voltage of the smallest cell at a future time, and if the predicted voltage is less than the pre-under-voltage threshold, then the predicted voltage may indicate that the battery pack may be under-voltage at the future time. At this time, the battery management system may control the allowable discharge current and/or the allowable discharge power of the battery pack according to a preset control strategy, for example, reduce the allowable discharge current and/or reduce the allowable discharge power. The battery management system may adjust the allowable discharge power or the allowable discharge current alone or both, depending on the specific application scenario and battery characteristics, while preventing the battery pack from being under-voltage.
In the above embodiment, in step S10, if the allowable discharge current and/or the allowable discharge power of the battery pack are/is adjusted based on the predicted voltage, that is, the actual allowable discharge current of the battery pack is different from the allowable discharge current obtained by looking up the table based on the remaining capacity and the temperature of the battery pack, the predicted voltage at the next sampling time is calculated based on the adjusted allowable discharge current.
In the embodiment, the battery management system compares the predicted voltage with the pre-undervoltage threshold value, and can predict whether the battery pack has an undervoltage risk in future time in advance, so that the undervoltage of the battery is prevented in advance, and the safety performance of the battery pack is improved.
The present application also provides a battery management system, referring to fig. 10, the battery management system includes:
The sampling circuit 10 is configured to obtain a remaining capacity, a temperature, and an actual voltage of a minimum battery cell at a current sampling time, and obtain an actual current and an allowable discharge current of a battery pack at the current sampling time, where the minimum battery cell is a battery cell with the minimum remaining capacity among a plurality of battery cells of the battery pack.
The controller 20 predicts a voltage drop of the battery pack at a future time due to accumulated polarization according to the remaining capacity and temperature of the minimum battery cell at the current sampling time, the actual current and allowable discharge current of the battery pack, and the actual voltages of the minimum battery cells at N sampling times before the current sampling time, determines a predicted voltage of the minimum battery cell at the future time according to the actual voltages and the voltage drop at the current sampling time, and controls the allowable discharge current and/or the allowable discharge power of the battery pack according to the predicted voltage.
The battery management system provided by the embodiment of the application can improve the accuracy of the voltage prediction result by adopting the discharge control method in the embodiment.
Compared with the prior art, the beneficial effects of the battery management system provided by the application are the same as those of the discharge control method provided by the embodiment, and other technical features in the battery management system are the same as those disclosed by the method of the embodiment, and are not repeated here.
The embodiment of the application also provides an electric device which comprises the battery management system in the embodiment, and the electric device can be an electric automobile, an electric bicycle, industrial electric equipment and the like.
It is to be understood that portions of the present disclosure may be implemented in hardware, software, firmware, or a combination thereof. In the description of the above embodiments, particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.
The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the application.

Claims (11)

1.一种放电控制方法，其特征在于，所述方法包括：1. A discharge control method, characterized in that the method comprises: 获取当前采样时刻下最小电池单体的剩余电量、温度和实际电压，并获取所述当前采样时刻下电池包的实际电流和许用放电电流，所述最小电池单体为所述电池包的多个电池单体中剩余电量最少的电池单体；Obtaining the remaining power, temperature and actual voltage of the smallest battery cell at the current sampling moment, and obtaining the actual current and allowable discharge current of the battery pack at the current sampling moment, wherein the smallest battery cell is the battery cell with the least remaining power among the multiple battery cells of the battery pack; 根据所述当前采样时刻下所述最小电池单体的剩余电量、温度，所述当前采样时刻下所述电池包的实际电流和许用放电电流，以及所述当前采样时刻和所述当前采样时刻之前的N个采样时刻所述最小电池单体的实际电压，预测未来时刻所述电池包由于累积极化所引起的压降；Predicting the voltage drop of the battery pack due to cumulative activation at a future time according to the remaining power and temperature of the smallest battery cell at the current sampling time, the actual current and the allowable discharge current of the battery pack at the current sampling time, and the actual voltage of the smallest battery cell at the current sampling time and N sampling times before the current sampling time; 根据所述当前采样时刻下所述实际电压和所述压降，确定所述未来时刻所述最小电池单体的预测电压；Determining the predicted voltage of the minimum battery cell at the future time according to the actual voltage and the voltage drop at the current sampling time; 根据所述预测电压控制所述电池包的许用放电电流和/或许用放电功率。The allowable discharge current and/or allowable discharge power of the battery pack is controlled according to the predicted voltage. 2.如权利要求1所述的方法，其特征在于，所述电池包由于累积极化所引起的压降包括：所述电池包由于欧姆极化所引起的第一压降、以及所述电池包由于浓差极化和电化学极化所引起的第二压降；2. The method according to claim 1, wherein the voltage drop of the battery pack caused by cumulative polarization comprises: a first voltage drop of the battery pack caused by ohmic polarization, and a second voltage drop of the battery pack caused by concentration polarization and electrochemical polarization; 所述根据所述当前采样时刻下所述最小电池单体的剩余电量、温度，所述当前采样时刻下所述电池包的实际电流和许用放电电流，以及所述当前采样时刻和所述当前采样时刻之前的N个采样时刻所述最小电池单体的实际电压，预测未来时刻所述电池包由于累积极化所引起的压降，包括：The method predicts the voltage drop of the battery pack due to cumulative activation at a future time according to the remaining power and temperature of the smallest battery cell at the current sampling time, the actual current and the allowable discharge current of the battery pack at the current sampling time, and the actual voltage of the smallest battery cell at the current sampling time and N sampling times before the current sampling time, including: 根据所述当前采样时刻下所述最小电池单体的剩余电量、温度，以及所述当前采样时刻下所述电池包的实际电流和许用放电电流，预测未来时刻所述电池包由于欧姆极化所引起的第一压降；Predicting a first voltage drop of the battery pack due to ohmic polarization at a future time according to the remaining power and temperature of the smallest battery cell at the current sampling time, and the actual current and allowable discharge current of the battery pack at the current sampling time; 根据所述当前采样时刻、及所述当前采样时刻之前的N个采样时刻所述最小电池单体的实际电压，预测未来时刻所述电池包由于浓差极化和电化学极化所引起的第二压降。According to the actual voltage of the smallest battery cell at the current sampling moment and N sampling moments before the current sampling moment, a second voltage drop of the battery pack caused by concentration polarization and electrochemical polarization at a future moment is predicted. 3.如权利要求2所述的方法，其特征在于，所述根据所述当前采样时刻下所述最小电池单体的剩余电量、温度，以及所述当前采样时刻下所述电池包的实际电流和许用放电电流，预测未来时刻所述电池包由于欧姆极化所引起的第一压降，包括：3. The method according to claim 2, characterized in that the predicting of the first voltage drop of the battery pack caused by ohmic polarization at a future time according to the remaining power and temperature of the smallest battery cell at the current sampling time, and the actual current and allowable discharge current of the battery pack at the current sampling time comprises: 根据所述当前采样时刻下所述最小电池单体的剩余电量、温度，确定所述当前采样时刻下所述电池包的欧姆阻抗；Determining the ohmic impedance of the battery pack at the current sampling moment according to the remaining power and temperature of the smallest battery cell at the current sampling moment; 根据所述当前采样时刻下所述电池包的实际电流、所述许用放电电流和所述欧姆阻抗，预测未来时刻所述电池包由于欧姆极化所引起的第一压降。According to the actual current of the battery pack at the current sampling moment, the allowable discharge current and the ohmic impedance, a first voltage drop of the battery pack caused by ohmic polarization at a future moment is predicted. 4.如权利要求3所述的方法，其特征在于，所述实际电流为带正负号的电流值，所述第一压降∆V1通过以下公式计算得到：4. The method according to claim 3, characterized in that the actual current is a current value with a positive or negative sign, and the first voltage drop ∆V1 is calculated by the following formula: ∆V1=(Ip-I)*R0∆V1=(Ip-I)*R0 其中，Ip为当前采样时刻下所述电池包的许用放电电流、I为当前采样时刻下所述电池包的实际电流、R0为当前采样时刻下所述电池包的欧姆阻抗。Among them, Ip is the allowable discharge current of the battery pack at the current sampling moment, I is the actual current of the battery pack at the current sampling moment, and R0 is the ohmic impedance of the battery pack at the current sampling moment. 5.如权利要求2所述的方法，其特征在于，所述根据所述当前采样时刻、及所述当前采样时刻之前的N个采样时刻所述最小电池单体的实际电压，预测未来时刻所述电池包由于浓差极化和电化学极化所引起的第二压降，包括：5. The method according to claim 2, characterized in that the predicting of the second voltage drop of the battery pack caused by concentration polarization and electrochemical polarization at a future time according to the actual voltage of the smallest battery cell at the current sampling time and N sampling times before the current sampling time comprises: 根据所述当前采样时刻、及所述当前采样时刻之前的N个采样时刻所述最小电池单体的实际电压，确定所述当前采样时刻之前N个采样周期的加权平均历史压降；Determine a weighted average historical voltage drop of N sampling periods before the current sampling moment according to the actual voltage of the minimum battery cell at the current sampling moment and N sampling moments before the current sampling moment; 根据所述当前采样时刻之前N个采样周期的加权平均历史压降，预测未来时刻所述电池包由于浓差极化和电化学极化所引起的第二压降。The second voltage drop of the battery pack caused by concentration polarization and electrochemical polarization at a future time is predicted according to the weighted average historical voltage drop of N sampling periods before the current sampling time. 6.如权利要求5所述的方法，其特征在于，所述根据所述当前采样时刻、及所述当前采样时刻之前的N个采样时刻所述最小电池单体的实际电压，确定所述当前采样时刻之前N个采样周期的加权平均历史压降，包括：6. The method according to claim 5, characterized in that the step of determining the weighted average historical voltage drop of N sampling periods before the current sampling moment according to the actual voltage of the minimum battery cell at the current sampling moment and N sampling moments before the current sampling moment comprises: 根据所述当前采样时刻、及所述当前采样时刻之前的N个采样时刻所述最小电池单体的实际电压，确定所述N个采样周期内所述最小电池单体的电压下降速率的变化趋势；Determine a change trend of a voltage drop rate of the minimum battery cell within the N sampling periods according to the actual voltage of the minimum battery cell at the current sampling moment and N sampling moments before the current sampling moment; 根据所述N个采样周期内所述最小电池单体的电压下降速率的变化趋势、以及变化趋势所对应的加权平均历史压降的计算方式，确定所述当前采样时刻之前N个采样周期的加权平均历史压降。The weighted average historical voltage drop of N sampling periods before the current sampling moment is determined according to the change trend of the voltage drop rate of the minimum battery cell within the N sampling periods and the calculation method of the weighted average historical voltage drop corresponding to the change trend. 7.如权利要求6所述的方法，其特征在于，所述根据所述N个采样周期内所述最小电池单体的电压下降速率的变化趋势、以及变化趋势所对应的加权平均历史压降的计算方式，确定所述当前采样时刻之前N个采样周期的加权平均历史压降，包括：7. The method according to claim 6, characterized in that the step of determining the weighted average historical voltage drop of N sampling periods before the current sampling moment according to the change trend of the voltage drop rate of the minimum battery cell in the N sampling periods and the calculation method of the weighted average historical voltage drop corresponding to the change trend comprises: 若所述变化趋势为：在所述N个采样周期内，连续p1个采样周期内所述最小电池单体的电压下降速率大于连续q1个采样周期内的所述最小电池单体的电压下降速率，其中，p1和q1之和小于或等于N，且所述连续p1个采样周期位于所述连续q1个采样周期之前，则所述N个采样周期的加权平均历史压降dV可用如下公式表示：If the change trend is: within the N sampling periods, the voltage drop rate of the minimum battery cell within p1 consecutive sampling periods is greater than the voltage drop rate of the minimum battery cell within q1 consecutive sampling periods, wherein the sum of p1 and q1 is less than or equal to N, and the p1 consecutive sampling periods are before the q1 consecutive sampling periods, then the weighted average historical voltage drop dV of the N sampling periods can be expressed by the following formula: dV=dV1*a+dV2*bdV=dV1*a+dV2*b 其中，dV1为连续p1个采样周期内的第一平均历史压降、dV2为连续q1个采样周期内的第二平均历史压降、a为所述第一平均历史压降的权重值、b为所述第二平均历史压降的权重值，a与b的和为1，且a大于或等于b。Among them, dV1 is the first average historical pressure drop within p1 consecutive sampling periods, dV2 is the second average historical pressure drop within q1 consecutive sampling periods, a is the weight value of the first average historical pressure drop, b is the weight value of the second average historical pressure drop, the sum of a and b is 1, and a is greater than or equal to b. 8.如权利要求6所述的方法，其特征在于，所述根据所述N个采样周期内所述最小电池单体的电压下降速率的变化趋势、以及变化趋势所对应的加权平均历史压降的计算方式，确定所述当前采样时刻之前N个采样周期的加权平均历史压降，包括：8. The method according to claim 6, characterized in that the step of determining the weighted average historical voltage drop of N sampling periods before the current sampling moment according to the change trend of the voltage drop rate of the minimum battery cell within the N sampling periods and the calculation method of the weighted average historical voltage drop corresponding to the change trend comprises: 若所述变化趋势为：在所述N个采样周期内，连续p2个采样周期内所述最小电池单体的电压下降速率小于或等于连续q2个采样周期内的所述最小电池单体的电压下降速率，其中，p2和q2之和小于或等于N，且所述连续p2个采样周期位于所述连续q2个采样周期之前，则所述N个采样周期的加权平均历史压降dV可用如下公式表示：If the change trend is: within the N sampling cycles, the voltage drop rate of the minimum battery cell within p2 consecutive sampling cycles is less than or equal to the voltage drop rate of the minimum battery cell within q2 consecutive sampling cycles, wherein the sum of p2 and q2 is less than or equal to N, and the p2 consecutive sampling cycles are before the q2 consecutive sampling cycles, then the weighted average historical voltage drop dV of the N sampling cycles can be expressed by the following formula: dV=dV3dV=dV3 其中，dV3为连续q2个采样周期内的第三平均历史压降。Wherein, dV3 is the third average historical voltage drop within q2 consecutive sampling periods. 9.如权利要求1所述的方法，其特征在于，其特征在于，所述根据所述预测电压控制所述电池包的许用放电电流和/或许用放电功率，包括：9. The method according to claim 1, wherein controlling the allowable discharge current and/or allowable discharge power of the battery pack according to the predicted voltage comprises: 在所述预测电压小于预欠压阈值的情况下，根据预设控制策略控制所述电池包的许用放电电流和/或许用放电功率。When the predicted voltage is less than the pre-undervoltage threshold, the allowable discharge current and/or allowable discharge power of the battery pack is controlled according to a preset control strategy. 10.一种电池管理系统，其特征在于，所述电池管理系统包括：10. A battery management system, characterized in that the battery management system comprises: 采样电路，用于获取当前采样时刻下最小电池单体的剩余电量、温度和实际电压，并获取所述当前采样时刻下电池包的实际电流和许用放电电流，所述最小电池单体为电池包的多个电池单体中剩余电量最少的电池单体；A sampling circuit, used to obtain the remaining power, temperature and actual voltage of the smallest battery cell at the current sampling moment, and to obtain the actual current and allowable discharge current of the battery pack at the current sampling moment, wherein the smallest battery cell is the battery cell with the least remaining power among the multiple battery cells of the battery pack; 控制器，用于根据所述当前采样时刻下所述最小电池单体的剩余电量、温度，所述当前采样时刻下所述电池包的实际电流和许用放电电流，以及所述当前采样时刻和所述当前采样时刻之前的N个采样时刻所述最小电池单体的实际电压，预测未来时刻所述电池包由于累积极化所引起的压降；根据所述当前采样时刻下所述实际电压和所述压降，确定所述未来时刻所述最小电池单体的预测电压；根据所述预测电压控制所述电池包的许用放电电流和/或许用放电功率。The controller is used to predict the voltage drop of the battery pack due to cumulative activating at a future moment according to the remaining power and temperature of the smallest battery cell at the current sampling moment, the actual current and the allowable discharge current of the battery pack at the current sampling moment, and the actual voltage of the smallest battery cell at the current sampling moment and N sampling moments before the current sampling moment; determine the predicted voltage of the smallest battery cell at the future moment according to the actual voltage and the voltage drop at the current sampling moment; and control the allowable discharge current and/or allowable discharge power of the battery pack according to the predicted voltage. 11.一种用电装置，其特征在于，所述用电装置包括如上述权利要求10所述的电池管理系统。11. An electrical device, characterized in that the electrical device comprises the battery management system as claimed in claim 10.
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111913111A (en) * 2020-07-24 2020-11-10 蜂巢能源科技有限公司 Discharge power correction method, discharge power correction device, storage medium and electronic equipment
CN116338476A (en) * 2021-12-24 2023-06-27 北京车和家汽车科技有限公司 Method, system, device and equipment for determining standard duration of battery depolarization

Family Cites Families (5)

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CN117360326A (en) * 2023-11-15 2024-01-09 广汽埃安新能源汽车股份有限公司 SOP power control method and device for power battery
CN117962690B (en) * 2024-03-20 2025-01-21 深蓝汽车科技有限公司 Discharge allowable power control method, device, vehicle and medium for power battery

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111913111A (en) * 2020-07-24 2020-11-10 蜂巢能源科技有限公司 Discharge power correction method, discharge power correction device, storage medium and electronic equipment
CN116338476A (en) * 2021-12-24 2023-06-27 北京车和家汽车科技有限公司 Method, system, device and equipment for determining standard duration of battery depolarization

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