CN109256607B - Group alternating-current preheating method for battery pack - Google Patents
Group alternating-current preheating method for battery pack Download PDFInfo
- Publication number
- CN109256607B CN109256607B CN201811145645.9A CN201811145645A CN109256607B CN 109256607 B CN109256607 B CN 109256607B CN 201811145645 A CN201811145645 A CN 201811145645A CN 109256607 B CN109256607 B CN 109256607B
- Authority
- CN
- China
- Prior art keywords
- battery pack
- preheating
- battery
- groups
- grouping
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- 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
- H01M10/60—Heating or cooling; Temperature control
- H01M10/61—Types of temperature control
- H01M10/615—Heating or keeping warm
-
- 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
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
-
- 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
- H01M10/4207—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells for several batteries or cells simultaneously or sequentially
-
- 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
- H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
-
- 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
- H01M10/48—Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte
- H01M10/486—Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte for measuring temperature
-
- 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
- H01M10/60—Heating or cooling; Temperature control
- H01M10/63—Control systems
-
- 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
- H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
- H01M2010/4271—Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Automation & Control Theory (AREA)
- Materials Engineering (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
- Secondary Cells (AREA)
Abstract
The invention provides a group alternating current preheating method for a battery pack, and belongs to the technical field of batteries. The method comprises the steps that firstly, battery units or modules are used as units to group battery packs, each battery group is connected with a battery pack charging interface by using a circuit with a switching device, all the battery groups are paired, and a control circuit is used for connecting two groups in each pairing; and then determining a battery grouping preheating regulation, judging whether the battery pack charging interface is connected with an external power supply or not if the battery pack is in a low-temperature environment, and preheating the battery pack according to the preheating regulation according to a judgment result. The invention can be implemented under the conditions of external power input and no external power input, and can effectively improve the preheating rate of the battery pack and the energy use efficiency during preheating.
Description
Technical Field
The invention relates to the technical field of batteries, in particular to a battery pack grouping alternating current preheating method.
Background
The lithium ion battery has the advantages of high energy density, long cycle life, low self-discharge rate, no memory effect and the like, and is the most suitable power source for the electric automobile at present compared with other batteries. However, under low temperature conditions (generally below 0 ℃), various impedances inside the lithium ion battery increase, which causes performance reduction during use, and the current commercial lithium ion battery negative electrode material mainly comprises graphite, which easily causes lithium metal on the graphite negative electrode during low-temperature charging, so that capacity attenuation and service life of the battery are reduced, and the continuous growth of the lithium metal can puncture a diaphragm, thereby causing internal short circuit, causing safety accidents such as thermal runaway and the like. After the temperature of the battery is raised to normal temperature or above 10 ℃ through preheating, the battery is in a normal working state, and the safety problem can be effectively avoided.
The low-temperature preheating method of the battery pack at present comprises two technical schemes of external preheating and internal preheating. The external preheating means preheating the battery by a heating element outside the battery pack until the temperature of the battery pack reaches a preset temperature, and although the method can effectively solve the problems of use and charging of the battery under a low-temperature condition, the method has the advantages of long time, low energy utilization efficiency and high cost, and can reduce the energy density of the battery pack; the internal preheating method is to realize preheating by utilizing the self heat production of the battery in the charging and discharging process, and the effective method comprises the step of preheating the battery by utilizing high-frequency large-amplitude alternating current.
Disclosure of Invention
The invention provides a group alternating current preheating method for a battery pack, which aims to solve the problems that large current is difficult to meet when the whole battery pack is preheated and the preheating efficiency of the battery pack is low when external preheating is adopted. The invention can be implemented under the conditions of external power input and no external power input, and can effectively improve the preheating rate of the battery pack and the energy use efficiency during preheating.
The invention provides a battery pack grouping alternating-current preheating method which is characterized by comprising the following steps:
(1) selecting a battery pack, grouping the battery pack by taking a single battery or a module as a unit, connecting each battery group with a battery pack charging interface by using a circuit with a switching device, pairing all the battery groups, and connecting two groups in each pairing by using a control circuit;
(2) determining a battery grouping preheating procedure for the battery pack selected in the step (1);
(3) the battery pack control system calculates the average temperature of the battery pack through temperature information acquired by a temperature sensor of the battery pack, and judges whether the battery pack is in a low-temperature environment at present according to a set low-temperature environment threshold value: if the average temperature of the battery pack is smaller than the low-temperature environment threshold value, the battery pack is in the low-temperature environment, and the step (4) is carried out; otherwise, the battery pack is not in a low-temperature environment, the grouping preheating is not carried out, and the method is ended;
(4) judging whether a battery pack charging interface is connected with an external power supply or not, and preheating the battery pack according to the preheating regulation formulated in the step (2) according to the judgment result: if the battery pack charging interface is not connected with an external power supply, the mutual charging and discharging among the groups is realized through a control circuit among the groups according to the preheating regulation; and if the battery pack charging interface is connected with an external power supply, alternating-current preheating is carried out on the batteries in groups alternately according to a preheating rule.
The invention has the characteristics and beneficial effects that:
the method provided by the invention can preheat by utilizing the heat produced by the battery, improves the energy utilization rate during preheating, has smaller requirement on the magnitude of charging current when the whole battery pack is preheated in groups, and can effectively solve the problem that the large current is difficult to meet when the whole battery pack is preheated.
2, the idea of grouping the battery packs is adopted, and the groups in the battery packs are alternately preheated under the condition of external power supply input, so that the problem that the charging pile is difficult to provide large current when the whole battery pack is preheated is effectively solved; under the condition of no external power supply input, the preheating is realized by utilizing the alternate charging and discharging of the two battery groups, the self energy of the battery is effectively utilized, and the energy utilization efficiency during the preheating is improved.
3 by the method provided by the invention, the preheating rate of the battery pack under the low-temperature condition can be effectively improved without adding an additional preheating element, and the battery pack can be effectively preheated under different use conditions, so that the use performance under the low-temperature condition is effectively ensured.
Drawings
FIG. 1 is an overall flow diagram of the method of the present invention.
Fig. 2 is a schematic diagram of a battery pack grouping design in an embodiment of the invention.
FIG. 3 is a graph showing the time-dependent variation of the packet voltage and current under the condition of no external power input in the embodiment of the invention.
Fig. 4 is a diagram illustrating a time-dependent average packet temperature during the preheating process without an external power input according to an embodiment of the present invention.
Fig. 5 is a graph illustrating the average packet temperature over time during a warm-up process with an external power input, in accordance with an embodiment of the present invention.
Detailed Description
The invention provides a group alternating-current preheating method for a battery pack, and the invention is further described in detail below by combining the attached drawings and specific invention examples.
The invention provides a battery pack grouping alternating-current preheating method, an overall flow chart is shown in figure 1, and the method comprises the following steps:
(1) the method comprises the steps of selecting a battery pack which can be any type of battery pack, grouping the battery packs by taking a single battery or a module as a unit, connecting each battery group with a battery pack charging interface by using a circuit with a switching device, pairing all the battery groups, and connecting two groups in each pairing by using a circuit with a function of controlling the mutual charging and discharging of the groups. The method comprises the following specific steps:
(1-1) selecting a battery pack, grouping the battery pack by taking single cells or modules as units, connecting the single cells or the battery modules in each group in a series, parallel or series-parallel mixed mode, determining the number of the single cells or the modules in each battery group and the connection mode among the single cells or the modules according to the three factors of the use requirement of a charging pile, the use requirement of a power electronic device and the grouping cost requirement, and ensuring the number of the battery groups to be double in order to facilitate pairing.
(1-2) after the grouping is completed, connecting each group with a charging interface by using a circuit with a switching device;
(1-3) determining the pairing relationship among all battery groups, selecting the groups with smaller voltage, capacity and internal resistance difference as much as possible to pair in pairs during pairing, and connecting the two groups in each pairing pair by using a control circuit after the pairing is finished, wherein the control circuit has the functions of controlling the mutual charging and discharging among the groups in the pairing and controlling whether the groups are connected or not. In the present embodiment, the functions are implemented by using a power electronic device with a control switch for controlling the on/off of the circuit and the protection circuit and a step-up/down function for controlling the mutual charge and discharge between the groups, for example, a power electronic device with a step-up/down function such as a bidirectional DC-DC converter may be used to control the mutual charge and discharge between the two groups, and the on/off of the circuit may be controlled by using a switching device such as an IGBT.
Fig. 2 is a schematic diagram showing the design of battery pack groups in the present embodiment, wherein battery groups 1, 2, 3, …, M represent the serial numbers of the battery packs after the battery packs are grouped, each group is connected to the charging interface of the battery pack through a circuit with a switching device, which may be a switching device such as an IGBT, a MOSFET, etc., switches 1, 2, 3, …, M represents the serial number of the switching device between each group and the charging interface, which is the same as the serial number of the group, a natural number M represents the number of the grouped groups as M, and M should be an even number; in addition, all battery groups need to be paired in pairs, related parameters such as capacity, open-circuit voltage and internal resistance of the groups need to be measured before the battery groups are paired, the two groups in close states are paired with each other, the paired groups are connected with each other through a circuit with the functions of controlling charging and discharging between the paired groups and controlling whether the paired groups are connected or not, the bidirectional DC-DC converter which is a power electronic device with the voltage boosting/reducing function can be used for controlling charging and discharging between the two groups, and on-off of the circuit is controlled by using a switching device such as an IGBT.
(2) Determining a battery grouping preheating procedure for the battery pack selected in the step (1); the grouping preheating regulation can be established according to the single battery preheating regulation or determined by directly utilizing an experimental or model method;
in an embodiment of the present invention, the packet preheating procedure includes voltage, current, and frequency of each packet during preheating, a threshold temperature corresponding to a switching packet during charging of the packet, and a difference of a state parameter between two packets during commutation of the voltage boost/buck device, where the difference of the state parameter between two packets may be a difference of parameters, such as voltage, temperature, capacity, and SOC, capable of representing a current state of the packet between two packets; in this embodiment, the SOC (state of charge) difference between two groups is selected as the state parameter difference when the step-up/step-down device commutates, and the group preheating procedure can be formulated in the following two ways: one is obtained by a proportional amplification mode on the basis of a single battery preheating regulation, but the inconsistency of the single batteries needs to be considered and corresponding safety margins need to be set; the other method is to directly make a grouping preheating procedure in an experimental or model mode by taking a battery group as an object
For the first mode, specifically, the cell charging schedule according to which the grouping preheating schedule is formulated should include information of charging voltages, currents, frequencies, and the like corresponding to different cell SOCs and different cell temperatures, assuming that the connection relationship between the cells included in the grouping is m parallel to n series (i.e., m cells are connected in parallel to form a parallel unit, and then n parallel units are connected in series, where the number of cells is m × n), if the charging voltage amplitude of the cell charging schedule under a certain temperature T and a certain SOC condition is U, the current amplitude is I, and the frequency is w, the grouping obtained by scaling is determined in such a way that the temperature T and the SOC charging voltage should be α nU, the current is α mI, the frequency is w, where α is a safety margin coefficient considering inconsistency between the cells in the grouping, α is determined in such a way that after the information related to the consistency of the cells of the battery pack is obtained (the information includes a deviation value between a discrete range of the capacity Q-Q, a discrete range of the discrete Q- Δ R + Q, and a maximum value of the discrete capacity R + Q + R of the cell production, where the average deviation of the cell Q is generally determined by the internal resistance Δ R + Q of the manufacturer, and the discrete range of the cell production of the manufacturing manufacturer, where Δ Q + Q, the discrete range of the discrete cells, the.
In addition, in the case where an external power supply is input, it is necessary to determine a threshold temperature corresponding to a switching group in addition to determining a voltage and a current, and the threshold temperature is determinedThe temperature needs to be determined by combining thermal insulation conditions of the whole battery pack, temperature rise rate of the groups, and the like on the basis of a single battery charging schedule, specifically, if the charging schedule of the single batteries includes a plurality of preheating stages (i.e., different temperature intervals corresponding to different voltages, currents, and frequencies during preheating), and the upper limit temperatures of the temperature intervals corresponding to the different preheating stages of the single batteries are T1, T2, …, and Tq, respectively, where q is the number of the temperature intervals corresponding to the preheating of the single batteries, the grouped preheating schedule should also include q preheating stages, the upper limit temperatures of the temperature intervals corresponding to the different preheating stages should be T1 ', T2', …, and Tq ', and should satisfy' Tx + Δ T, where x is a natural number in an interval from 1 to q, which means the x-th preheating stage, and Δ T is a preheating increment, and should be determined by combining the thermal insulation conditions of the battery pack, the confirmation method comprises the following steps: firstly, heating a battery group to a temperature (for example, 10 ℃) capable of being normally charged or operated in a low-temperature environment (for example, -20 ℃) to obtain a temperature change curve of the battery group in the whole cooling process, obtaining a temperature change rate dT/dT by calculating the slope of an upper limit temperature point of a temperature interval in different preheating stages of the curve, then estimating the corresponding preheating time delta t of the group in different preheating stages by using a single preheating experiment or a grouped preheating experiment, and using a formula
Wherein M represents the number of groups, i.e. the increment delta T to be set by the temperature grouping preheating regulation of each stage can be determined, and the temperature increment corresponding to different preheating stages is different according to the method
For the case of no external power input, it is necessary to determine a threshold Δ SOC of the SOC difference between the corresponding pair groups at the time of switching the mode of the step-up/step-down device in the control circuitcMore specifically, when the difference in SOC between two packets is greater than a threshold Δ SOCcThen, the step-up/step-down device switches the direction, changes the roles of the two original groups, then carries out charging and discharging, repeats the above processes until the group temperature reaches the preset temperature, and in addition, the threshold value delta SOCcThe maximum allowable SOC difference of the battery pack during equalization is determined slightly smaller thanThe difference value.
In the second method, the battery group is used as the target, and the determination is performed by an experiment or numerical model, the determination of the rule should refer to the determination of the preheating rule of the single battery (i.e. under the condition of ensuring the safety of the battery, the charging current, voltage and corresponding frequency value under different temperature and battery SOC conditions are determined by using the numerical model of the single battery or the charging experiment of the single battery), under the condition of ensuring the safety of the battery in the battery group, the corresponding information such as the charging voltage, charging current and charging frequency of the group under different temperature and different SOC conditions is determined by using the numerical model of the group (the group can be established by considering the series-parallel relation among the single batteries in the group on the basis of the numerical model of the single battery) or the experiment, and then, on the basis of the battery pack, according to the obtained information of the charging voltage, the charging current, the charging frequency and the like of the single grouping under the conditions of different temperatures and different grouping SOCs, the temperature threshold value for charging the switching grouping under the condition of an external power supply is determined, the determination method of the threshold value temperature in the first rule of the determination method of the threshold value is the same, and finally the charging preheating rule of the corresponding grouping is obtained.
(3) Judging whether the battery pack is in a low-temperature environment
The control system of the battery pack calculates the average temperature of the battery pack through temperature information collected by a temperature sensor of the battery pack, and judges whether the battery pack is in a low-temperature environment at present according to a set low-temperature environment threshold value, wherein the low-temperature environment threshold value can be set according to actual requirements, and generally speaking, when the average temperature of the battery pack is lower than 0 ℃, the battery pack can be considered to be in the low-temperature environment. If the average temperature of the battery pack is smaller than the low-temperature environment threshold value, the battery pack is in the low-temperature environment, and then the step (4) is carried out; otherwise, the battery pack is not in a low-temperature environment, the grouping preheating is not needed, and the method is ended;
(4) judging whether a battery pack charging interface is connected with an external power supply or not, and preheating the battery pack according to the preheating regulation formulated in the step (2) according to the judgment result;
in an embodiment of the invention, when the battery pack enters a low-temperature charging or use stage (when the battery pack is in the use stage, the internal impedance of the battery under the low-temperature condition is large, the multiplying power performance is poor, and the battery pack is not beneficial to starting), the battery pack control system judges whether an external power supply is connected to the battery pack through the charging interface under the condition that no external power supply is connected, and according to the preheating procedure formulated in the step (2), the mutual charging and discharging among the groups is realized through the control circuit among the groups, and the alternating-current preheating is realized for each group; the specific method comprises the following steps: after entering a preheating stage, the control circuit switches on the two pairing groups and controls one of the pairing groups to charge the other grouping, when the difference value of the state parameters between the pairing groups meets the corresponding threshold value condition, the mutual charging and discharging relation between the two grouping is converted, namely the former charged grouping is used as a discharging grouping, the former discharging grouping is used as a charging grouping to charge and discharge, the processes are repeated until the average temperature of the battery pack reaches the preset temperature, and the preheating is finished. It should be noted that, since the direction of the current flowing across the two groups is periodically changed during the charging and discharging of the two groups, the current belongs to the alternating current for the single group
In one embodiment of the present invention, an SOC is taken as an example of a pair group of circuit connections including a bidirectional DC-DC converter and an IGBT control switch, and a corresponding state parameter of a charge-discharge relationship between the groups is converted into two groups
Specifically, after the switching element (IGBT element in this embodiment) on the control circuit is closed, the control system obtains temperature information and SOC information of each group of the battery pack, and controls the bidirectional DC-DC converter to select one of the groups with a relatively high SOC value in the pairing process or a group with a low SOC as a power source, and then the control system preheats the charging and discharging of the two groups according to the preheating rule formulated in step (2), in the whole process, the changes of the voltage and the current between the pairing groups with time are respectively shown in fig. 3(a) and fig. 3(b), and U in fig. 3(a)1And U2Representing the voltage values across packet 1 and packet 2, I in FIG. 3(b)1And I2Representing the value of the current flowing through packet 1 and packet 2, and the dotted line representing the value of the current flowing between the two packetsThe corresponding time when the relative voltage magnitude changes is the same as the corresponding time when the current direction changes, it can be seen that the voltage directions of the two groups do not change along with the time, only in different periods, the voltage values can have differences due to the different charging and discharging relations between the two groups, and in the initial stage, U is in the same state1Has a voltage value higher than U2At this time, the packet 1 is in a discharging state, the packet 2 is in a charging state, and after the SOC difference between the two reaches a threshold value in the second stage, the charging and discharging relationship between the two is switched, and the voltage magnitude relationship between the two packets becomes U2Has a voltage value higher than U1. In the whole process, the voltage magnitude at two ends of each group changes periodically, the current direction and magnitude change periodically, and for a single group, the current for preheating belongs to alternating current because the direction of the current changes periodically. In addition, the change rule of the average temperature of the single group along with time in the whole preheating process can refer to fig. 4, namely in the whole preheating process, the temperature rises fast in the initial stage, and the temperature rise speed is slow in the later stage of preheating.
Under the condition that an external power supply is connected, alternating current preheating is carried out on the batteries in groups alternately according to a set preheating regulation; the on-off between the grouping and the charging interface is controlled by a power electronic device with a switch function, and the grouping is alternately preheated by switching the device until the average temperature of the battery pack reaches a preset temperature, and the preheating is finished. In the preheating stage, the grouped charging and discharging current waveform is at least one of square wave, triangular wave, pulse, step and trigonometric function.
In one embodiment of the present invention, when an external power is input, it is determined that the battery pack is in a low-temperature charging stage, and the control switch between the distribution pair groups described in step (1) should be turned off
And (3) after the control switch is switched off, the control system selects the group with the lowest average temperature or takes the minimum group in the group sequence as a target group, controls the switching device of the branch where the target group is located to be closed, switches on the charging pile and the target group, and preheats according to the group regulation in the step (2). When the target group reaches the threshold temperature, the next group is switched to preheat until the temperatures of all the groups reach the target temperature value, and the time-dependent change rule of the temperatures in the whole preheating process can refer to fig. 5
FIG. 5 is a diagram showing the time-dependent temperature change when the battery pack is divided into two groups and the battery pack is alternately warmed up in the groups according to the embodiment, wherein tswitch,iThe time corresponding to the switching grouping is shown, Ti is the grouping average temperature corresponding to the switching grouping, wherein i is a natural number, and i is the number of different preheating stages corresponding to the preheating rule; when the preheating is started, the control system selects the packet (shown as packet 1) with the lowest temperature in the pairing packets for preheating, when the average temperature of the packet reaches the corresponding switching temperature T1 in the preheating procedure, the control system opens the connection circuit between the packet and the external power interface, closes the switching device between the packet 2 and the external power interface, and starts the preheating, because the packet 1 is not heated in the process, the packet is in a process of exchanging heat with the external low-temperature environment, the temperature slightly drops, when the average temperature of the packet 2 also reaches the switching temperature, the packet 1 with the lower temperature is switched, and finally, the preheating is stopped until the average temperature of the two packets reaches the target temperature.
Claims (3)
1. A battery pack grouped alternating current preheating method is characterized by comprising the following steps:
(1) selecting a battery pack, grouping the battery pack by taking a single battery or a module as a unit, connecting each battery group with a battery pack charging interface by using a circuit with a switching device, pairing all the battery groups, and connecting two groups in each pairing by using a control circuit;
(2) determining a battery grouping preheating procedure for the battery pack selected in the step (1); the group preheating rule comprises the voltage, the current and the frequency of each group during preheating, the threshold temperature corresponding to a switching group during group charging and the state parameter difference value between the two groups during reversing of the voltage boosting/reducing device;
(3) the battery pack control system calculates the average temperature of the battery pack through temperature information acquired by a temperature sensor of the battery pack, and judges whether the battery pack is in a low-temperature environment at present according to a set low-temperature environment threshold value: if the average temperature of the battery pack is smaller than the low-temperature environment threshold value, the battery pack is in the low-temperature environment, and the step (4) is carried out; otherwise, the battery pack is not in a low-temperature environment, the grouping preheating is not carried out, and the method is ended;
(4) judging whether a battery pack charging interface is connected with an external power supply or not, and preheating the battery pack according to the preheating regulation formulated in the step (2) according to the judgment result:
if the battery pack charging interface is not connected with an external power supply, the mutual charging and discharging among the groups is realized through a control circuit among the groups according to the preheating regulation, and the specific method comprises the following steps: after entering a preheating stage, the control circuit switches on the two pairing groups and controls one of the pairing groups to charge the other grouping, when the difference value of the state parameters between the pairing groups meets the corresponding threshold value condition, the mutual charging and discharging relation between the two groupings is converted, namely the former charged grouping is used as a discharging grouping, the former discharging grouping is used as a charging grouping to charge and discharge, the processes are repeated until the average temperature of the battery pack reaches the preset temperature, and the preheating is finished;
if the battery pack charging interface is connected with an external power supply, alternating-current preheating is carried out on the batteries in groups alternately according to a preheating regulation, and the specific method comprises the following steps: the on-off between the grouping and the charging interface is controlled by a power electronic device with a switch function, and the grouping is alternately preheated by switching the device until the average temperature of the battery pack reaches a preset temperature, and the preheating is finished.
2. The method of claim 1, wherein the step (1) comprises the following steps:
(1-1) selecting a battery pack, grouping the battery pack by taking a single battery or a module as a unit, connecting the single batteries or the battery modules in each group in a series, parallel or series-parallel mixed mode, wherein the number of the battery groups is a double number;
(1-2) after the grouping is finished, connecting each group with a battery pack charging interface by using a circuit with a switching device;
(1-3) determining the pairing relationship among all battery groups, and after the pairing is completed, connecting two groups in each pairing pair by using a control circuit, wherein the control circuit is used for controlling the mutual charging and discharging among the groups in the pairing pair and the connection among the groups.
3. The method of claim 1, wherein the packet preheating procedure of step (2) is formulated in two ways: the first mode is formulated according to a single battery preheating regulation, firstly, the single battery preheating regulation is obtained, the battery grouping preheating regulation is obtained in a proportion amplification mode, and corresponding safety margin is set, and the second mode is that the battery grouping preheating regulation is determined by using an experiment or model method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811145645.9A CN109256607B (en) | 2018-09-29 | 2018-09-29 | Group alternating-current preheating method for battery pack |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811145645.9A CN109256607B (en) | 2018-09-29 | 2018-09-29 | Group alternating-current preheating method for battery pack |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109256607A CN109256607A (en) | 2019-01-22 |
| CN109256607B true CN109256607B (en) | 2020-05-22 |
Family
ID=65047032
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811145645.9A Active CN109256607B (en) | 2018-09-29 | 2018-09-29 | Group alternating-current preheating method for battery pack |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109256607B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111261978B (en) * | 2020-01-16 | 2021-11-23 | 武汉理工大学 | Energy storage power station winter heat preservation method based on energy storage battery alternating current preheating |
| CN112895976B (en) * | 2021-02-01 | 2022-06-24 | 重庆峘能电动车科技有限公司 | Battery cell early warning protection method and system |
| CN115832525B (en) * | 2021-09-28 | 2024-05-14 | 宁德时代新能源科技股份有限公司 | A heating system, a heating method and a heating device, and an electric device |
| CN114091404B (en) * | 2022-01-20 | 2022-05-17 | 天津力神电池股份有限公司 | Electric-thermal model of lithium ion battery |
| CN115954579A (en) * | 2022-12-09 | 2023-04-11 | 华中科技大学 | A method and device for uniformly preheating a battery at low temperature without external power supply |
| CN117293425B (en) * | 2023-11-24 | 2024-04-19 | 宁德时代新能源科技股份有限公司 | Battery module, battery, power-consuming device and battery discharge control method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103715473A (en) * | 2012-09-29 | 2014-04-09 | 北京有色金属研究总院 | Thermal management system of power battery |
| CN105190987A (en) * | 2013-05-08 | 2015-12-23 | 株式会社Lg化学 | Battery warm-up system and battery warm-up method using the same |
| CN105375087A (en) * | 2015-12-22 | 2016-03-02 | 哈尔滨理工大学 | Low-temperature preheating system for battery pack of electric vehicle and control method of low-temperature preheating system |
| JP2017228544A (en) * | 2017-09-27 | 2017-12-28 | エスゼット ディージェイアイ テクノロジー カンパニー リミテッドＳｚ Ｄｊｉ Ｔｅｃｈｎｏｌｏｇｙ Ｃｏ．，Ｌｔｄ | Battery preheating method, device, and equipment |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202308190U (en) * | 2011-08-18 | 2012-07-04 | 合肥国轩高科动力能源有限公司 | A new tab high-rate lithium-ion battery |
| CN203339728U (en) * | 2013-05-07 | 2013-12-11 | 国家电网公司 | A battery charge and discharge equalization control circuit |
| CN103326417B (en) * | 2013-05-07 | 2015-06-17 | 国家电网公司 | Charge-discharge equalization control circuit of battery pack |
| CN106025410B (en) * | 2016-07-22 | 2018-07-24 | 哈尔滨理工大学 | A kind of battery variable current heating means for electric vehicle |
| CN107738591A (en) * | 2017-11-01 | 2018-02-27 | 邱诗俊 | Batteries of electric automobile pre-heating system |
-
2018
- 2018-09-29 CN CN201811145645.9A patent/CN109256607B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103715473A (en) * | 2012-09-29 | 2014-04-09 | 北京有色金属研究总院 | Thermal management system of power battery |
| CN105190987A (en) * | 2013-05-08 | 2015-12-23 | 株式会社Lg化学 | Battery warm-up system and battery warm-up method using the same |
| CN105375087A (en) * | 2015-12-22 | 2016-03-02 | 哈尔滨理工大学 | Low-temperature preheating system for battery pack of electric vehicle and control method of low-temperature preheating system |
| JP2017228544A (en) * | 2017-09-27 | 2017-12-28 | エスゼット ディージェイアイ テクノロジー カンパニー リミテッドＳｚ Ｄｊｉ Ｔｅｃｈｎｏｌｏｇｙ Ｃｏ．，Ｌｔｄ | Battery preheating method, device, and equipment |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109256607A (en) | 2019-01-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109256607B (en) | Group alternating-current preheating method for battery pack | |
| US12325329B2 (en) | Battery system with adjustable heating rate and control method thereof | |
| CN109301366B (en) | Battery pack circuit and battery pack heating method | |
| CN114050330B (en) | Battery system and power supply system | |
| CN112152280B (en) | Multivariable balance control method for power battery | |
| CN112186305B (en) | Low-temperature battery hybrid self-heating device and self-heating method based on same | |
| JP5996151B1 (en) | Battery system | |
| Sinkaram et al. | Modeling battery management system using the lithium-ion battery | |
| CN107845840A (en) | Battery heater circuit | |
| CN105356007B (en) | It is a kind of to the pre-warmed method and system of battery pack | |
| CN204315687U (en) | Lithium-ion-power cell bag constant temp. heating management system | |
| CN109301399B (en) | Multi-branch regional power battery system heating method and system | |
| CN113809438A (en) | Battery system and power supply system | |
| Wai et al. | Design of energy-saving adaptive fast-charging control strategy for Li-FePO4 battery module | |
| CN108039538A (en) | Vehicle mounted dynamic battery low temperature exchange heating-equilibrium integration topology and method | |
| Coşkun et al. | Cold plate enabling air and liquid cooling simultaneously: Experimental study for battery pack thermal management and electronic cooling | |
| CN115084724A (en) | Vehicle, lithium dendrite control method, battery management system and computer equipment | |
| CN207459113U (en) | Battery heater circuit | |
| Oehl et al. | High frequency alternating current heating method for Li-Ion cells based on boost converter topology | |
| CN207967253U (en) | Battery pack low-temperature heating device, battery module and vehicle | |
| CN111162351B (en) | A kind of power battery self-heating method and its system and automobile | |
| US20250046906A1 (en) | Battery self-heating device and method, and vehicle | |
| JP2013094033A (en) | Power storage device and power supply system | |
| CN104409789B (en) | A kind of charging method under the battery electric quantity imbalance with temperature protection function | |
| Huang et al. | A fast energy-efficient pulse preheating strategy for Li-Ion battery at subzero temperatures |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |