JP3202196U - Charging cable and charger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a charging cable and a charger capable of greatly reducing the charging time without significantly reducing the operating time of an electronic device in a charged state. A charging cable 10 for connecting an external power source 100 and a secondary battery 202 of an electronic device 200 has an input unit 20 to which DC power is input from the external power source and a charging current for charging the secondary battery. The output unit 30 for outputting, the input unit and the output unit are connected, the wiring 40 through which the charging current flows, the switch 50 provided in the wiring, the circuits Ad1, GND, R1 for detecting the charging current, and the charging current And a control unit 60 that determines that 80% to 90% of the total capacity of the secondary battery is charged based on the detection result, and switches the switch from the conductive state to the non-conductive state. [Selection] Figure 2

Description

  The present invention relates to a charging cable and a charger used for charging a secondary battery of an electronic device such as a mobile phone.

  The electronic circuit of a charging device that directly charges a secondary battery such as a lithium-ion battery detects the end-of-charge voltage, which is the voltage between the terminals of the battery when it is fully charged, and determines whether it is fully charged. It is stopped (Patent Document 1).

Japanese Patent Laying-Open No. 2005-312104 (0002, 0039)

  The charging current decreases when the capacity of the secondary battery exceeds a predetermined ratio (for example, 80% or more) of the total capacity (maximum discharge capacity Ah). Moreover, it is said that the life of a secondary battery will be shortened if full charge is repeated.

An object of some aspects of the present invention is to provide a charging cable and a charger that can significantly reduce the charging time without significantly reducing the operating time of the electronic device in a charged state.
An object of some aspects of the present invention is to provide a charging cable and a charger that can extend the life of a secondary battery of an electronic device to be charged.

(1) One aspect of the present invention is a charging cable for connecting an external power source and a secondary battery of an electronic device.
An input unit to which DC power is input from the external power source;
An output unit for outputting a charging current for charging the secondary battery of the electronic device;
The input unit and the output unit are connected, the wiring through which the charging current flows,
A switch provided in the wiring;
A circuit for detecting the charging current;
A controller that determines that 80% to 90% of the total capacity of the secondary battery is charged based on a detection result of the charging current, and switches the switch from a conductive state to a non-conductive state; ,
The present invention relates to a charging cable having

  According to one aspect of the present invention, when the input unit is connected to an external power source (AC / DC converter, DC / DC converter, DC power source, battery pack, etc.) and the output unit is connected to an electronic device, the external power source The secondary battery of the electronic device can be charged via the charging cable. A charging current flowing through the wiring of the charging cable is detected during charging, and based on the detection result, the control unit determines that 80% to 90% of the total capacity of the secondary battery is charged. The switch is switched from the conductive state to the non-conductive state. Thereby, the charging of the secondary battery is completed before reaching the full charge. Since the charging current decreases when the capacity of the secondary battery exceeds 80% of the total capacity (maximum discharge capacity Ah), the charging of the secondary battery is completed before reaching the full charge, Charging time can be greatly reduced. However, since 80% to 90% of the total capacity of the secondary battery is charged, the operation time of the electronic device in the charged state is not significantly shortened. In addition, since the full charge is not repeated, the life of the secondary battery of the electronic device to be charged can be extended.

  (2) In one aspect of the present invention, the control unit can determine an overcurrent based on the detection result of the charging current and switch the switch from a conductive state to a non-conductive state. In this way, it is possible to secure a safety function that automatically stops charging when an overcurrent is detected.

  (3) In one aspect of the present invention, the output unit includes a temperature detection element, and the control unit switches the switch from a conduction state to a non-conduction state based on a temperature detection result of the temperature detection element. be able to. In this way, it is possible to ensure a safety function that senses an abnormal temperature rise and automatically stops charging.

  (4) In one aspect of the present invention, an ECO mode that terminates charging when 80% to 90% of the total capacity of the secondary battery is charged, and 90% of the total capacity of the secondary battery It is possible to further have an operation unit for switching the control unit to one of two modes: a normal mode in which charging is terminated with full charge exceeding. Thus, the user can arbitrarily select one of the ECO mode and the normal mode.

  (5) In one aspect of the present invention, the operation unit stops charging by the control unit while the input unit is connected to the external power source, and charges by the control unit after stopping or ending charging. It can also be used as a charge start / stop switch for resuming. Thus, by using the operation unit for a plurality of functions, the charging cable can be reduced in size while improving the functions.

  (6) In an aspect of the present invention, the control unit may further include a mode display unit that is turned on in one of the two modes and turned off in the other of the two modes. In this way, it is possible to recognize which of the two modes is set by turning on / off the mode display section.

  (7) In one aspect of the present invention, the control unit may further include a charge display unit that is blinked during charging and switched to lighting when charging ends in either of the two modes. In this way, it is possible to recognize whether the charging is in progress or the end of the charging by blinking / lighting the charging display section.

  (8) In one aspect of the present invention, the input unit may have a USB connector. In this way, the external power source that can be connected to the input unit can be expanded to devices having a USB port such as an AC / DC converter, a DC / DC converter, a DC power source, a charger, and a personal computer.

  (9) In one aspect of the present invention, the output unit may include a micro USB connector. In this way, electronic devices that can be connected to the output unit can be extended to various mobile phones having a micro USB port.

  (10) In one aspect of the present invention, a first casing in which the input unit is provided, a second casing in which the output unit and the control unit are provided, the first casing and the second casing, And a cable that electrically connects the input unit, the control unit, and the output unit. Thus, a charging cable in which the first housing is connected to one end of the cable and the second housing is connected to the other end of the cable can be configured.

  (11) In one aspect of the present invention, the operation unit defined in (4) or (5) can be provided in the second casing. In this way, the operation unit and the control unit can be connected at the shortest distance without going through the cable.

  (12) In an aspect of the present invention, the mode display unit defined in (6) can be provided in the second casing. Thus, the mode display unit and the control unit can be connected at the shortest distance without going through the cable.

  (13) In one aspect of the present invention, the charge display unit defined in (7) can be provided in the second casing. In this way, the charging display unit and the control unit can be connected at the shortest distance without going through the cable.

(14) Another aspect of the present invention provides a charger for charging a secondary battery of an electronic device,
A power supply for supplying DC power;
An output unit for outputting a charging current for charging the secondary battery of the electronic device;
The power supply unit and the output unit are connected, and the wiring through which the charging current flows,
A switch provided in the wiring;
A circuit for detecting the charging current;
A controller that determines that 80% to 90% of the total capacity of the secondary battery is charged based on a detection result of the charging current, and switches the switch from a conductive state to a non-conductive state; ,
It is related with the charger which has.

  Another aspect of the present invention defines a charger that combines the charging cable defined in (1) and a power supply unit that supplies DC power. According to another aspect of the present invention, when the output unit is connected to an electronic device, the power supply unit (AC / DC converter, DC / DC converter, built-in battery, etc.) supplying DC power supplies the secondary of the electronic device. The battery can be charged. A charging current flowing through the wiring is detected during charging, and based on the detection result, the control unit determines that 80% to 90% of the total capacity of the secondary battery is charged, and switches the switch. Switch from conductive state to non-conductive state. Thereby, the charging of the secondary battery is completed before reaching the full charge. Since the charging current decreases when the capacity of the secondary battery exceeds 80% of the total capacity (maximum discharge capacity Ah), the charging of the secondary battery is completed before reaching the full charge, Charging time can be greatly reduced. However, since 80% to 90% of the total capacity of the secondary battery is charged, the operation time of the electronic device in the charged state is not significantly shortened. In addition, since the full charge is not repeated, the life of the secondary battery of the electronic device to be charged can be extended.

  (15) In another aspect of the present invention, a first casing provided with the power supply unit and the control unit, a second casing provided with the output unit, the first casing and the second casing. And a cable that connects the body and electrically connects the power supply unit, the control unit, and the output unit. Thus, a charger in which the first housing is connected to one end of the cable and the second housing is connected to the other end of the cable can be configured.

1 is an overall view of a charging cable according to a first embodiment of the present invention. It is a circuit diagram of the charging cable shown in FIG. It is a figure which shows the charge characteristic of a mobile telephone. It is a figure which shows the charge characteristic of the mobile phone different from FIG. It is a general view of the charger which concerns on 2nd Embodiment of this invention. It is a circuit diagram of the charger shown in FIG. It is a characteristic view which shows the relationship between charging / discharging cycle number and battery capacity about ECO mode and normal mode.

  Hereinafter, preferred embodiments of the present invention will be described in detail. The present embodiment described below does not unduly limit the contents of the present invention described in the claims, and all the configurations described in the present embodiment are indispensable as means for solving the present invention. Not always.

1. First embodiment (charging cable)
First, a first embodiment in which the present invention is applied to a charging cable will be described. In FIG. 1, the charging cable 10 includes a first housing 12, a second housing 14, and a cable 16 that connects the first housing 12 and the second housing 14. The first housing 12 is provided with a connector, for example, a USB connector 12A that is connected to the external power source 100 shown in FIG. The second housing 14 is provided with a connector, for example, a micro USB connector 14A, which is connected to an electronic device 200 such as a mobile phone incorporating the secondary battery 202 to be charged shown in FIG. The second housing 14 can be provided with an operation unit 17 and a display unit 18 (mode display unit 18A, charge display unit 18B). The electronic device 200 includes a secondary battery 202 and an electronic circuit 204 having a function of charging the secondary battery 202 and the like.

  Here, the operation unit 17 sets the ECO mode in which charging is terminated when 80% to 90% is charged with respect to the total capacity of the secondary battery in the electronic device to be charged, and the total capacity of the secondary battery. On the other hand, it is possible to perform a mode switching operation for switching to one of two modes: a normal mode in which charging is terminated with a full charge exceeding 90%. Thus, the user can arbitrarily select one of the ECO mode and the normal mode. The operation unit 17 can also be used as a charge start / stop switch that stops charging while the USB connector 12A is connected to an external power source, and restarts charging after stopping or ending charging. In the present embodiment, one operation unit 17 is used as a mode switch and a charge start / stop switch. Thus, by using the operation unit 17 for a plurality of functions, the charging cable 10 can be reduced in size while improving the functions.

  The mode display unit 18A, which is one of the display units 18, is turned on when one of the two modes (for example, the ECO mode) and turned off when the other of the two modes (for example, the normal mode). In this way, it is possible to recognize which of the two modes is set by turning on / off the mode display portion 18A.

  The charge display unit 18B, which is another one of the display unit 18, blinks during charging in either of the two modes, and is switched on when charging ends. In this way, it is possible to recognize whether charging is in progress or charging is complete by blinking / lighting of the charging display section 18B. The charging display unit 18B is lit when the USB connector 12A is connected to an external power supply, and blinks when charging is in progress.

  In FIG. 2, a charging cable 10 is connected to an input unit 20 to which DC power is input from an external power source, for example, an AC / DC converter 100, and a mobile phone 200, which is an electronic device. An output unit 30 that outputs a charging current for charging (ion battery) 202, and an input unit 20 and an output unit 30 are connected to each other, and wiring 40 through which the charging current flows is provided.

  Here, the input unit 20 is disposed in the first housing 12 shown in FIG. 1 and includes a USB connector 12A. The output unit 30 includes the micro USB connector 14A shown in FIG. The wiring 40 includes a high potential line 40A and a low potential line (ground wiring) 40B. As shown in FIG. 2, only the wiring 40 is arrange | positioned at the cable 16 shown in FIG.

  In FIG. 2, the charging cable 10 further includes a switch 50 provided in, for example, the high potential wiring 40 </ b> A of the wiring 40. The switch 50 can be composed of, for example, an FET switch. Charging is possible when the switch 50 is in a conductive state, and charging is stopped or terminated when the switch 50 is in a non-conductive state.

  In FIG. 2, the charging cable 10 includes a control unit 60 configured by, for example, a microcomputer. The controller 60 may include a GND (ground) terminal, an Ad1 terminal, an Ad2 terminal, and the like.

  In FIG. 2, the charging cable 10 further has a low resistance R1 connected in series with, for example, a low potential line 40B that connects between the input unit 20 and the output unit 30 in order to detect a charging current. The node where the low potential line 40B is connected to one end of the low resistance R1 is connected to the GND terminal of the control unit 60, and the node where the low potential line 40B is connected to the other end of the low resistance R1 is Ad1 of the control unit 60. Connected to the terminal. This constitutes a charging current detection circuit that detects the charging current at the Ad1 terminal as the voltage across the low resistance R1.

  As shown in FIG. 2, the control unit 60 is connected to the operation unit 17 and the display unit 18. When the ECO mode is selected by the operation unit 17, it is determined that 80% to 90% of the total capacity of the secondary battery 202 of the electronic device 200 is charged based on the detection result of the charging current. Then, the switch 50 is switched from the conductive state to the non-conductive state, and the charging is terminated. When the normal mode is selected by the operation unit 17, the control unit 60 has a charge state exceeding 90% with respect to the total capacity of the secondary battery 202 of the electronic device 200 based on the detection result of the charge current, for example, full charge (100%) is determined, the switch 50 is switched from the conductive state to the non-conductive state, and the charging is terminated. In any mode, the control unit 60 controls display of the display unit 18 in a predetermined state.

  3 and 4 show charging characteristics of two types of mobile phones 200 from different manufacturers. 3 and 4, the charging current decreases when approaching the charged state of the full capacity (maximum discharge capacity Ah) of the secondary battery 202 of the mobile phone 200. 3 and 4, the threshold value Ath1 corresponding to a ratio (for example, 85%) of 80% to 90% of the total capacity of the secondary battery 202 and 90% of the total capacity of the secondary battery 202 are shown. A threshold value Ath2 corresponding to an excess ratio (for example, 95% or more) is shown. The control unit 60 can execute the charge end control in the ECO mode or the charge end control in the normal mode by comparing the detected charging current with a threshold Ath1 or Ath2 stored in advance. In order to share the charging cable 10 with a plurality of models having different charging characteristics, the control unit 60 can acquire model information and compare the threshold Ath1 or Ath2 selected according to the model with the charging current.

  The control unit 60 can determine overcurrent based on the detection result of the charging current described above, and can switch the switch 50 from the conductive state to the non-conductive state. For this purpose, the control unit 60 stores a threshold Ath3 whose current value is higher than the normal charging current shown in FIGS. 3 and 4 and determines that the detected current is overcurrent when the detected charging current exceeds the threshold Ath3. . In this way, it is possible to secure a safety function that automatically stops charging when an overcurrent is detected.

  In the present embodiment, as shown in FIG. 2, a temperature detection thermistor R2 is further connected between the Ad2 terminal and the GND terminal, and a fixed resistor R3 is further provided between the high potential line 40A and the Ad2 terminal. it can. The resistance value of the temperature detection thermistor R2 varies depending on the temperature. Therefore, the voltage between the high potential line 40A and the GND terminal is divided by the resistors R2 and R3, and the voltage input to the Ad2 terminal varies depending on the temperature. The control unit 60 can determine an abnormal temperature rise based on the voltage input to the Ad2 terminal. In this way, it is possible to ensure a safety function that senses an abnormal temperature rise and automatically stops charging. In order to determine an abnormal temperature rise in the electronic device 200, the temperature detection thermistor R <b> 2 is preferably provided in the output unit 30. Further, in the present embodiment, the above-described safety function can be ensured regardless of the conduction / non-conduction state of the switch 50. For this reason, as shown in FIG. 2, the resistor R3 is preferably connected to a node on the high potential line 40A located on the input unit 20 side with respect to the switch 50. In this way, after the switch 50 is turned off by the safety function, the control unit 60 can perform the following control when the user tries to restart charging by operating the operation unit 17. . That is, the control unit 60 first determines the voltage of the Ad2 terminal based on the signal from the operation unit 17 without immediately turning on the switch 50, and the abnormal temperature is maintained based on the determination result. Sometimes the switch 50 can be maintained in a non-conductive state.

  When an overcurrent or an abnormal temperature rise is detected by the above-described safety function, a warning may be displayed on the display unit 18. As a warning display, for example, the charging display unit 18B can be blinked faster than blinking indicating normal charging. The user can disconnect the charging cable 10 from the external power supply 100 and the electronic device 200 in response to the warning display.

  2, the output unit 30, the control unit 60, and the resistors R1 to R3 described above are arranged together with the operation unit 17 and the display unit 18 in the second housing 14 illustrated in FIG. Thus, the control unit 60 can be connected to each of the output unit 30, the resistors R <b> 1 to R <b> 3, the operation unit 17, and the display unit 18 at the shortest distance without going through the cable 16.

2. Second embodiment (charger)
Next, 2nd Embodiment which applied this invention to the charger is described with reference to FIG.5 and FIG.6. 5 and 6, members having the same functions as those shown in FIGS. 1 and 2 are given the same reference numerals, and detailed descriptions thereof are omitted. In FIG. 5, the charger 70 includes a first housing 72, a second housing 74, and a cable 76 that connects the first housing 72 and the second housing 74. The first housing 72 is provided with, for example, an AC plug 72A. The first housing 72 can further be provided with an operation unit 17 and a display unit 18 (mode display unit 18A, charge display unit 18B). The second housing 74 is provided with a connector, for example, a micro USB connector 74 (14A) that is connected to the electronic device 200 such as a mobile phone incorporating the secondary battery 202 to be charged shown in FIG.

  6 which is a circuit diagram of the second embodiment is different from FIG. 2 which is a circuit diagram of the first embodiment as follows. First, the charger 70 shown in FIG. 6 includes an AC / DC converter that is the external power supply 100 in FIG. That is, the charger 70 of the second embodiment is functionally one in which the power source 100 is connected to the charging cable 10 of the first embodiment. As FIG. 5 which is the whole of the second embodiment differs from the appearance of FIG. 1 which is the whole view of the first embodiment, the first housing 72 shown in FIG. Wiring 40 (40A, 40B), switch 50, control unit 60, AC plug 72A, AC / DC converter 80, and resistors R1, R3 are arranged. In the second housing 74 shown in FIG. 6, the wiring 40 (40A, 40B), the micro USB connector 74A (14A), and the resistor R2 are arranged. Instead of the AC / DC converter 80 serving as the power supply unit, a member that can supply DC power, such as a DC / DC converter, a DC power supply, or a battery pack, may be used.

  The operation of the charger 70 according to the second embodiment is the same as that of the connection of the charging cable 10 and the external power source 100 according to the first embodiment. In particular, the selection of the ECO mode / normal mode, the start / stop of charging ( End) Operations, various displays, safety functions, warning displays, and the like can be performed in the same manner as in the first embodiment. Only when the temperature detection resistor R2 is disposed in the output unit 30 as shown in FIG. 6, the connection between the control unit 60 and the temperature detection resistor R2 is via the cable 76.

3. Characteristics improved by implementing the ECO mode 3.1. Reduction of charging time Table 1 below compares the charging time in the ECO mode and the normal mode for two models with different manufacturers.

Of the charging times of the secondary batteries in Table 1, when the charging time in the normal mode is 100, the charging time of the secondary battery in the ECO mode is as shown in Table 2 below.

  From Table 2, for example, the charging time in the ECO mode for charging up to 85% is about 60% of the charging time in the normal mode for charging up to 100%, and the charging time can be shortened by about 40%.

3.2. Improvement of secondary battery life FIG. 7 shows the number of charge / discharge cycles on the horizontal axis, the effective battery capacity (%) with respect to the total capacity of the battery on the vertical axis, and the empirical and expected lines for the ECO mode and the normal mode. It is shown. Here, the secondary battery used for the demonstration is a lithium ion battery. In the ECO mode, charging / discharging for charging up to 85% when the battery is discharged to 55% of the total capacity of the battery is defined as one cycle. In the normal mode, charging / discharging for charging up to 100% when discharged to 70% of the total capacity of the battery was defined as one cycle. According to the empirical line obtained as a result of repeating up to around 1000 cycles, the slope in which the ratio (%) of the effective capacity to the total capacity of the battery decreases according to the number of cycles is steeper in the normal mode than in the ECO mode. As can be seen from the expected line expected when the number of cycles is further increased, it can be seen that the battery life deteriorates faster in the normal mode than in the ECO mode.

  Although the present embodiment has been described in detail as described above, it will be easily understood by those skilled in the art that many modifications can be made without departing from the novel matters and effects of the present invention. Therefore, all such modifications are included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Charging cable, 12 ... 1st housing | casing, 12A ... Connector (USB connector), 14 ... 2nd housing | casing, 14A ... Connector (micro USB connector), 16 ... Cable, 17 ... Operation part, 18 ... Display part, 18A ... Mode display section, 18B ... Charging display section, 20 ... Input section, 30 ... Output section, 40 ... Wiring, 40A ... High potential wiring, 40B ... Low potential wiring, 50 ... Switch, 60 ... Control section, 70 ... Charging 80, power supply unit (internal power supply), Ad1, Ad2 ... detection terminal, Ath1, Ath2 ... threshold, GND ... ground terminal, R1 ... low resistance, R2 ... temperature detection element, R3 ... fixed resistance, Ad1, R1, GND: Charging current detection circuit

Claims (15)

In the charging cable that connects the external power supply and the secondary battery of the electronic device,
An input unit to which DC power is input from the external power source;
An output unit for outputting a charging current for charging the secondary battery of the electronic device;
The input unit and the output unit are connected, the wiring through which the charging current flows,
A switch provided in the wiring;
A circuit for detecting the charging current;
A controller that determines that 80% to 90% of the total capacity of the secondary battery is charged based on a detection result of the charging current, and switches the switch from a conductive state to a non-conductive state; ,
A charging cable characterized by comprising: The charging cable according to claim 1,
The control unit determines an overcurrent based on a detection result of the charging current, and switches the switch from a conductive state to a non-conductive state. The charging cable according to claim 1 or 2,
The output unit includes a temperature detection element,
The said control part switches the said switch from a conduction | electrical_connection state to a non-conduction state based on the temperature detection result in the said temperature detection element, The charging cable characterized by the above-mentioned. The charging cable according to any one of claims 1 to 3,
ECO mode that terminates charging when 80% to 90% of the total capacity of the secondary battery is charged, and normal termination of charging with full charge exceeding 90% of the total capacity of the secondary battery The charging cable further includes an operation unit that switches the control unit to one of the two modes. The charging cable according to claim 4,
The operation unit is also used as a charge start / stop switch that stops charging by the control unit while the input unit is connected to the external power source, and restarts charging by the control unit after stopping or ending charging. A charging cable characterized by being made. The charging cable according to claim 4 or 5,
The charging cable further comprising a mode display unit that is turned on in one of the two modes by the control unit and is turned off in the other of the two modes. The charging cable according to any one of claims 4 to 6,
The charging cable further comprising a charge display unit that is blinked during charging and switched to lighting when charging ends in either of the two modes by the control unit. The charging cable according to any one of claims 1 to 7,
The charging cable, wherein the input unit has a USB connector. The charging cable according to claim 8,
The output cable has a micro USB connector. The charging cable according to any one of claims 1 to 9,
A first housing provided with the input unit;
A second housing provided with the output unit and the control unit;
A cable that connects the first housing and the second housing and electrically connects the input unit, the control unit, and the output unit;
A charging cable further comprising: The charging cable according to claim 10, which is dependent on claim 4 or claim 5,
The operation cable is provided in the second housing. The charging cable according to claim 10, which is dependent on claim 6,
The mode display unit is provided in the second casing, and is a charging cable. The charging cable according to claim 10, which is dependent on claim 7,
The charging cable, wherein the charging display unit is provided in the second housing. In chargers that charge secondary batteries for electronic devices,
A power supply for supplying DC power;
An output unit for outputting a charging current for charging the secondary battery of the electronic device;
The power supply unit and the output unit are connected, and the wiring through which the charging current flows,
A switch provided in the wiring;
A circuit for detecting the charging current;
A controller that determines that 80% to 90% of the total capacity of the secondary battery is charged based on a detection result of the charging current, and switches the switch from a conductive state to a non-conductive state; ,
A charger characterized by comprising: The charger according to claim 14, wherein
A first housing provided with the power supply unit and the control unit;
A second housing provided with the output unit;
A cable that connects the first housing and the second housing and electrically connects the power supply unit, the control unit, and the output unit;
The battery charger further comprising: