Classifications

• • 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
  • H02J7/0013—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
  • H02J7/0014—Circuits for equalisation of charge between batteries
  • H02J7/0016—Circuits for equalisation of charge between batteries using shunting, discharge or bypass 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
  • H02J7/34—Parallel operation in networks using both storage and other DC sources, e.g. providing buffering
  • H02J7/345—Parallel operation in networks using both storage and other DC sources, e.g. providing buffering using capacitors as storage or buffering devices
• • 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
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/60—Other road transportation technologies with climate change mitigation effect
  • Y02T10/70—Energy storage systems for electromobility, e.g. batteries

Definitions

• the present invention relates to a power storage device using a power storage element.
• Patent Document 1 power storage device power as an auxiliary power source capable of supplying sufficient power including when a battery is abnormal is proposed in Patent Document 1, for example.
• FIG. 13 is a schematic circuit diagram of such a conventional power storage device.
• a capacitor cell 110 consisting of a large-capacity electric double layer capacitor is used for the storage element!
• a plurality of these are connected in series to form a capacitor pack 112. Since the capacitor pack 112 is connected to a power source such as a battery, the capacitor cell 110 is charged by this power source.
• Each capacitor cell 110 is connected in parallel with a load, such as a balance resistor 114, in order to balance the voltage between both ends thereof.
• a relace switch 116 is connected between each capacitor cell 110 and each balance resistor 114.
• the release switch 116 includes a normally-open type relay contact 116a that forms a switch part and an electromagnetic coil 116b that drives the switch part.
• Each electromagnetic coil 116b is connected in parallel between the power supply and ground.
• the accessory switch 118 is connected to the power supply side. Therefore, when the accessory switch 118 is turned on, all the electromagnetic coils 116b are driven, and the relace switch 116 is turned on.
• the accessory switch 118 is turned on by the idance key.
• all the re-switches 116 are turned on, and the capacitor cell 110 and the balance resistor 114 are connected in parallel. Accordingly, power is applied to each capacitor cell 110, charging starts, and the balance resistor 114 is connected, so that the voltage across each capacitor cell 110 is automatically adjusted to be equal. The As a result, the capacitor cell 110 can be prevented from being overcharged and the life can be extended.
• each capacitor cell 110 is independent of the wiring force, so that it retains the charge that was charged before the vehicle stopped. This prevents unnecessary discharge from the capacitor cell 110 and continues to store electricity for a long time. Such an operation makes it possible to supply power in preparation for engine restart.
• FIG. 14 shows the change with time of the voltage across the capacitor cell 110 at this time.
• the horizontal axis represents time
• the vertical axis represents the voltage across the capacitor cell.
• the time t2 to reach the voltage VI has a large variation width! /, The length of the variation becomes longer. Therefore, if the leaving time when the vehicle is stopped is short, the conventional configuration with a small variation width is relatively The voltage VI is reached in a short time. However, if the vehicle is left for a long time with the vehicle stopped, the time until voltage balance is obtained (hereinafter referred to as “balance time”) is on the order of several hours due to variations in the self-discharge of the capacitor cell 110. It was long.
• the balance time is determined by the time constant obtained from the capacitance value of the capacitor cell 110 and the resistance value of the balance resistor 114. In this case, the capacitance value of the power storage device necessary as an auxiliary power source for the vehicle is determined. Therefore, the resistance value of the balance resistor 114 affects the balance time.
• the resistance value of the balance resistor 114 is preferably a large value in order to suppress discharge from the capacitor cell 110 as much as possible and reduce unnecessary power consumption.
• the balance time becomes long. It had to be decided to a proper resistance value. For this reason, there is a problem that the balance time at the start of the vehicle becomes long depending on the variation width of the voltage across the capacitor cell 110 due to the vehicle being left for a long time. As a result, it takes a long time for the capacitor cell 110 to be overcharged until the voltage is balanced, and the life of the capacitor cell 110 may be shortened.
• Patent Document 1 JP-A-10-201091
• the present invention solves the above-described conventional problems, and can store a voltage in a short time even when the variation width of the voltage across the storage element is large, and can suppress unnecessary power consumption. Providing equipment.
• the power storage device of the present invention includes a voltage equalization circuit connected in parallel to the power storage element, and when the power storage element is charged, a predetermined time (t 1) from the start of charging Discharges part or all of the current charged by the voltage equalization circuit until the voltage of the storage element reaches approximately the predetermined voltage (VI), and then performs charging by reducing the discharge current. is there.
• a predetermined time (t 1) from the start of charging Discharges part or all of the current charged by the voltage equalization circuit until the voltage of the storage element reaches approximately the predetermined voltage (VI), and then performs charging by reducing the discharge current. is there.
• the voltage equalization circuit includes a resistance resistor connected in parallel for each power storage element, or a plurality of power storage elements as one unit and connected in parallel for each.
• a control unit that measures the voltage across the storage element connected to the voltage equalization circuit and controls on / off of the balance switch and the discharge switch.
• the voltage equalization circuit includes a resistance resistor connected in parallel for each power storage element, or a plurality of power storage elements as one unit and connected in parallel for each.
• a discharge resistor having a balance resistor, a balance switch connected between one end of the storage element and the balance resistor, and having a resistance value smaller than that of the balance resistor, connected in parallel to the storage element; It has a discharge switch connected between one end of the storage element and the discharge resistor. The voltage across the storage element connected to the voltage equalization circuit is measured, and the non-sense switch and the discharge switch It is further provided with a control unit for controlling on / off.
• voltage balance is achieved by discharging a part or all of the power stored in the power storage element during charging, so the variation width of the voltage across the power storage element is large.
• voltage balance can be achieved in a short time, and after further voltage balance is achieved, the discharge current is reduced and charging is performed, so that a power storage device that can suppress unnecessary power consumption thereafter can be realized.
• FIG. 1 is a schematic circuit diagram of a power storage device according to Embodiment 1 of the present invention.
• FIG. 2 is a time-dependent change diagram of the voltage across the storage element when the charging current of the storage device in Embodiment 1 of the present invention is larger than the discharge current.
• FIG. 3 is a time-dependent change diagram of the voltage across the storage element when the charging current of the storage device in Embodiment 1 of the present invention is smaller than the discharge current.
• FIG. 4 is another schematic circuit diagram of the power storage device according to Embodiment 1 of the present invention.
• FIG. 5 is a schematic circuit diagram of a power storage device according to Embodiment 2 of the present invention.
• FIG. 6 is a time-dependent change diagram of the voltage across the storage element of the storage device according to Embodiment 2 of the present invention.
• FIG. 7 is another schematic circuit diagram of the power storage device in Embodiment 2 of the present invention.
• FIG. 8 is a schematic circuit diagram of a power storage device according to Embodiment 3 of the present invention.
• FIG. 9 is a time-dependent change diagram of the voltage across storage element when the charging current of the storage device in Embodiment 3 of the present invention is larger than the discharge current.
• FIG. 10 is a time-dependent change diagram of the voltage across the storage element when the charging current of the storage device in Embodiment 3 of the present invention is smaller than the discharge current.
• FIG. 11 is another schematic circuit diagram of the power storage device in the third embodiment of the present invention.
• FIG. 12A is a connection circuit diagram in the case where a plurality of power storage elements are connected in parallel to one voltage equalization circuit.
• FIG. 12B is a connection circuit diagram when a plurality of power storage elements are connected in series and parallel to one voltage equalization circuit.
• FIG. 13 is a schematic circuit diagram of a conventional power storage device.
• FIG. 14 is a time-dependent change diagram of the voltage across the capacitor cell of the conventional power storage device. Explanation of symbols
• FIG. 1 is a schematic circuit diagram of the power storage device according to Embodiment 1 of the present invention.
• FIG. 2 is a time-dependent change diagram of the voltage across the storage element when the charging current is larger than the discharging current in the power storage device according to Embodiment 1 of the present invention.
• FIG. 3 is a time-dependent change diagram of the voltage across the electric storage element when the charging current is smaller than the discharging current in the electric storage device according to Embodiment 1 of the present invention.
• FIG. 4 is another schematic circuit diagram of the power storage device according to Embodiment 1 of the present invention.
• a storage element 1 is composed of an electric double layer capacitor having a rated voltage of 2.5 V, and a plurality of these are connected in series to provide necessary power.
• a voltage equalization circuit 2 is connected to each of the storage elements 1 in parallel!
• the detailed configuration of voltage equalization circuit 2 is as follows. First, a balance resistor 3 is connected in parallel to each power storage element 1.
• the resistance values of the respective resistor resistors 3 are set to be approximately equal, and the absolute value thereof is set to the order of 100 ⁇ in order to suppress the discharge current when balancing the voltage and reduce unnecessary power consumption.
• a balance switch 5 is connected to the wiring between one end of the electricity storage element 1 and the balance resistor 3, respectively.
• the balance switch 5 may be any switch that can be turned on and off from the outside like a conventional release switch.
• each balance switch 5 in FIG. 1 is configured to be turned on and off at the same time as indicated by a dotted line.
• Each balance resistor 3 is connected to a discharge resistor 7 in parallel.
• the discharge resistor 7 is also connected to the power storage element 1 in parallel.
• the resistance value of each discharge resistor 7 is set to be approximately equal, and its absolute value is set to be smaller than the resistance value of the balance resistor 3, specifically several ⁇ . In this way, the resistance value of the balance resistor 3 is made one digit or more larger than the resistance value of the discharge resistor 7.
• a discharge switch 9 is connected to the wiring between the power storage element 1 and the discharge resistor 7. Similarly to the balance switch 5, the discharge switch 9 may be any switch that can be turned on and off from the outside. As shown by the dotted lines in each discharge switch 9 in FIG. 1, these are also turned on / off at the same time! In this way, the voltage equalization circuit 2 is configured!
• the voltage equalization circuit 2 uses the discharge resistor 7 to store the electric power stored in the storage element 1. It can be discharged with a large current. Also, by turning off only the discharge switch 9 in this state, since the resistance value of the balance resistor 3 is one digit or more larger than the resistance value of the discharge resistor 7, the amount of current discharged from the storage element 1 (discharge Current) can be reduced
• the balance switch 5 and the discharge switch 9 are on / off controlled by the control unit 10. The detailed operation of the control unit 10 will be described later.
• the power storage device 11 configured as described above includes a charging circuit that controls charging of the power storage element 1.
• the power storage device 11 is also connected to a load for supplying the power.
• the idle switch 13 is turned on.
• the electric power of battery 15 is controlled by charging circuit 12, and charging of power storage device 1 is started.
• the balance switch 5 and the discharge switch 9 are all turned on by the control of the control unit 10 in conjunction with the turning on of the idle switch 13.
• the discharge switch 9 is used to discharge the storage element 1 with the discharge resistor 7 having a small resistance value.
• the balance switch 5 must be turned on.
• each storage element 1 is in a state where the balance resistor 3 and the discharge resistor 7 are connected in parallel. Therefore, the electric power of each storage element 1 stored when the vehicle was last stopped is discharged by the balance resistor 3 and the discharge resistor 7, but the resistance value of the balance resistor 3 is the resistance of the discharge resistor 7. since an order of magnitude or more larger than the value, may large current I to the discharge resistor 7 ⁇ 0
• FIGS. 2 and 3 show changes with time in the voltage across the storage element 1 at this time. 2 and 3, the horizontal axis represents time, and the vertical axis represents the voltage across the storage element.
• FIG. 2 shows a case where the charging current at the start of charging is larger than the discharging current flowing through the discharging resistor 7.
• This case corresponds to a state in which the charging current is larger than that although the discharging resistor 7 with a small amount of electric charge stored in the electric storage element 1 at the time of activation is performed.
• a part of the charging current is offset with the discharging current flowing through the discharge resistor 7, so that a part of the charging current is apparently discharged.
• FIG. 3 shows a case where the charging current at the start of charging is smaller than the discharging current flowing through the discharging resistor 7.
• the charging circuit 12 having a large amount of charge stored in the power storage element 1 at the time of startup, this corresponds to a state in which the discharge current by the discharge resistor 7 is larger than that.
• the charging current is completely offset with the discharging current flowing through the discharge resistor 7, so that all of the charging current is apparently discharged.
• Embodiment 1 the voltage balance of power storage element 1 can be achieved by time tl, and thereafter, only discharge switches 9 are all turned off. Since balance switch 5 is already on, leave it as it is. Thereby, the discharge current of the electricity storage element 1 is reduced. In this case, by keeping the balance switch 5 on, the voltage balance of each power storage element 1 can be maintained with a small amount of discharge. Therefore, unnecessary power consumption can be suppressed as in the conventional case, and the life of the power storage device 1 can be extended by preventing overvoltage.
• time tl may vary depending on the state of storage element 1 (temperature, progress of deterioration, etc.). Therefore, the voltage detection circuit (not shown) is used to accurately represent the voltage across each storage element 1. It is most desirable if the condition is when the voltage across all the storage elements 1 has reached the predetermined voltage VI. Note that it is difficult to accurately reach the voltage across all the storage elements 1 to the predetermined voltage VI. If it reaches, it will progress to the following operations.
• the voltage equalizing circuit 2 Turn on all discharge switches 9 and balance switch 5 to discharge part or all of the current to be charged. Thereafter, the control unit 10 turns off all the discharge switches 9 and turns on all the switch switches 5. As a result, the large current discharged immediately after the voltage equalization circuit 2 is started becomes extremely small after that when the above condition is satisfied.
• the large current discharged immediately after the voltage equalization circuit 2 is started is configured to be one digit or more larger than the consumption current after the condition is satisfied.
• the storage element 1 is charged by the charging current from the charging circuit 12.
• discharge by the discharge resistor 7 is not performed and the discharge current by the balance resistor 3 is extremely small, so that the gradient of the charge voltage after time tl increases.
• each power storage element 1 is independent of the wiring force, so that no discharge occurs, and each power storage element 1 is in a state of holding the charge that was charged before the vehicle stopped. As a result, unnecessary discharge from the power storage element 1 is prevented, and power storage is continued for a long time. Such an operation makes it possible, for example, to supply electric power in preparation for engine restart.
• the discharge resistor 7 having a resistance value smaller than that of the balance resistor 3 is provided in parallel with the storage element 1, and part or all of the charging current is discharged by the discharge resistor 7 during charging. Voltage balance. In this way, it is possible to achieve a voltage balance in a short time even when the fluctuation width of the voltage across the power storage element 1 is large, and to realize a power storage device that suppresses unnecessary power consumption.
• each storage element 1 includes a balance resistor 3 connected in parallel, and a balance switch 5 connected between the storage element 1 and the balance resistor 3, respectively, and connected in parallel to the storage element 1.
• a configuration including a discharge resistor 7 having a resistance value smaller than that of the balance resistor 3 and a discharge switch 9 connected between the storage element 1 and the discharge resistor 7 may be employed.
• the operation of power storage device 11 in FIG. 4 may be the same as the operation of power storage device 11 in FIG. 1.
• only discharge switch 9 is turned on.
• the discharge switch 9 is turned off and the balance switch 5 is turned on.
• the power storage element 1 may be charged. Therefore, all the balance switches 5 must be turned on in the configuration of FIG. 1 during charging, but it is not always necessary to turn on the balance switch 5 in the configuration of FIG. Therefore, all the balance switches 5 may be turned on as necessary depending on the circuit configuration of the power storage device 11.
• unnecessary power consumption is suppressed by performing an operation of turning off all the balance switches 5 and the discharge switches 9 as in the configuration of FIG.
• FIG. 5 is a schematic circuit diagram of the power storage device according to Embodiment 2 of the present invention.
• FIG. 6 is a time-dependent change diagram of the voltage across the storage element of the storage device according to Embodiment 2 of the present invention.
• FIG. 7 is another schematic circuit diagram of the power storage device according to Embodiment 2 of the present invention.
• the same components as those in FIG. 1 are denoted by the same reference numerals and detailed description thereof is omitted.
• the configuration feature of the second embodiment is that, as shown in FIG. 5, the control line 19 is connected between the control unit 10 and the charging circuit 12, and the control unit 10 outputs the output of the charging circuit 12. This is the point that enables on / off control, and the point that the control unit 10 can measure the voltage across the storage element 1.
• the operation of such a power storage device will be described.
• the idance switch 13 When the idance switch 13 is turned on by starting the vehicle, the power of the battery 15 is controlled by the charging circuit 12 and charging of the electric storage element 1 is started.
• the charging circuit 12 is set so as to supply a charging current larger than the discharging current of all the storage elements 1 when all the discharge switches 9 and the balance switches 5 are turned on. Therefore, as described in FIG. 2 in the first embodiment, the charging current is set to be always larger than the discharging current flowing through the discharge resistor 7.
• FIG. 6 shows the change with time of the voltage across the storage element 1 at this time.
• the horizontal axis represents time
• the vertical axis represents the voltage across the storage element.
• the variation width of the voltage across the storage element 1 is the width shown in FIG. 6 at the time tO at the time of start-up. Charging is performed so that the variation width of the voltage at both ends becomes small (the voltage at both ends increases). As a result, the voltage across all the storage elements 1 exceeds the required voltage V2 after a certain period of time.
• the required voltage V2 is a voltage obtained by giving a predetermined margin to the voltage V3 across each storage element 1 for obtaining the minimum output voltage required for the storage device 11. The margin should be determined in advance from the discharge characteristics of power storage device 1! /.
• the control unit 10 measures the voltage across each power storage element 1 and turns off the output of the charging circuit 12 via the control line 19 when the voltage across all the power storage elements 1 exceeds the required voltage V2. At this time, since all of the balance switch 5 and the discharge switch 9 remain on, most of the electric power stored in the storage element 1 flows to the discharge resistor 7, and the voltage across all of the storage elements 1 rapidly increases. descend.
• the control unit 10 outputs the output of the charging circuit 12 again via the control line 19. Turn on. At this time, since the voltage balance of the storage element 1 is maintained, all the discharge switches 9 are simultaneously turned off. Thereafter, the storage element 1 is charged in this state.
• the discharge switch 9 since the discharge switch 9 is off, the discharge current only flows to the balance resistor 3, but the resistance value of the balance resistor 3 is more than one digit larger than the resistance value of the discharge resistor 7, so the above control It is possible to charge efficiently by reducing the discharge current.
• the condition for turning on the output of the charging circuit 12 again is when the predetermined time t3 has elapsed or when the respective voltages of the storage element 1 have become substantially the predetermined voltage V3. As mentioned above, the latter is preferable because it is more accurate.
• the circuit configuration of the power storage device 11 in FIG. 5 includes a balance resistor 3 connected in parallel for each power storage element 1, and one end of the power storage element 1 and the balance resistor 3 as shown in FIG.
• Discharge resistor 7 having a balance switch 5 connected in between and having a resistance value smaller than that of the balance resistor 3 connected in parallel with the storage element 1, and one end of the storage element 1 and the discharge resistance
• the control line 19 is connected between the control unit 10 and the charging circuit 12.
• Other configurations are the same as in FIG. By adopting such a configuration, the same effect as described in FIG. 4 of Embodiment 1 can be obtained.
• the operation of power storage device 11 in FIG. 7 may be the same as the operation in FIG. However, when balancing the voltage at the start of charging, only the discharge switch 9 is turned on. When the voltage of the storage element 1 exceeds the required voltage V2 due to charging, the output of the charging circuit 12 is turned off. When the predetermined time t3 has elapsed, or when the respective voltage of the storage element 1 becomes substantially the predetermined voltage V3, the output of the charging circuit 12 is turned on. At the same time, the power storage device 1 may be charged with all the discharge switches 9 turned off and all the balance switches 5 turned on. When the use of the power storage device 11 is completed, unnecessary power consumption is suppressed by performing an operation of turning off all the balance switches 5 as in the configuration of FIG.
• FIG. 8 is a schematic circuit diagram of the power storage device according to Embodiment 3 of the present invention.
• FIG. 9 is a time-dependent change diagram of the voltage across the storage element when the charging current of the storage device in Embodiment 3 of the present invention is larger than the discharge current.
• FIG. 10 is a time-dependent change diagram of the voltage across the storage element when the charging current of the storage device in Embodiment 3 of the present invention is smaller than the discharging current.
• FIG. 11 is another schematic circuit diagram of the power storage device according to Embodiment 3 of the present invention.
• FIG. 12A shows one voltage equalization circuit in the power storage device according to Embodiment 3 of the present invention.
• FIG. 12B is a connection circuit diagram in the case where a plurality of power storage elements are connected in series and parallel to one voltage equalization circuit in the power storage device according to Embodiment 3 of the present invention.
• FIG. 8 the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.
• Each discharge switch 9 can be individually turned on / off.
• a control unit 10 having a function for measuring the voltage across the storage element 1 and an on / off control function for the non-switch 5 and the discharge switch 9 is provided.
• the control unit 10 turns on all the balance switches 5 at the same time, measures the voltage across each storage element 1, and other than the discharge switch 9 connected to the storage element 1 having the minimum voltage across the other switches. Set all discharge switches 9 to ON. As a result, the storage elements 1 other than the storage element 1 having the lowest voltage across the terminal also start to discharge by the discharge resistor 7.
• the resistance value of the balance resistor 3 is one digit or more larger than the resistance value of the discharge resistor 7, so that the discharge resistor 7 connected to the on-state discharge switch 9 is discharged.
• the current becomes a large current. Specifically, it is one digit or more larger than the current flowing through balance resistor 3.
• FIGS. 9 and 10 show changes with time in the voltage across the storage element 1 at this time.
• the horizontal axis indicates time
• the vertical axis indicates the voltage across the storage element.
• the charge current and discharge current states in Figs. 9 and 10 are the same as those in Figs. 2 and 3, respectively.
• FIG. 9 that is, the case where the charging current is larger than the discharging current by the discharging resistor 7 will be described.
• the variation width of the voltage across the storage element 1 is the width shown in FIG. 9 at the time tO at the start-up, and charging is started in this state.
• the storage element 1 having the minimum voltage at the both ends (the lowest voltage of the variation width) is in a state in which the discharge resistor 7 is not connected, and the discharge current flowing through the balance resistor 3 is very small.
• the other storage element 1 is a discharge resistor 7 Since the charging current is larger than the discharging current here, the voltage rises although the slope of the voltage is smaller than in the case of only charging.
• the voltage across storage element 1 having the lowest voltage across both ends approaches the current voltage across storage element 1 having the second voltage from the bottom of the variation width (time tOl) in a very short time.
• the control unit 10 constantly measures the change in the voltage across the both ends, and the difference between the voltage across the arbitrary storage element 1 and the current voltage across the storage element 1 with the minimum terminal voltage is within a predetermined value (this embodiment 3).
• the time tOl which is assumed to be within 5% of the rated charge voltage of storage element 1
• the discharge connected to storage element 1 having the second voltage from the bottom of the variation width By controlling the switch 9 to be turned off, the discharge current of the electricity storage device 1 is controlled to be reduced.
• the storage element 1 having the second voltage from the bottom stops the discharge current due to the discharge resistor 7, only the charging is performed after the time tOl as in the storage element 1 having the minimum voltage across the terminals.
• the voltage across the storage element 1 having the second voltage from the bottom is approximately equal to the voltage across the storage element 1 having the minimum voltage across the battery, and therefore, as shown in FIG.
• the voltage across storage element 1 with the second voltage from the bottom rises with the same slope so as to match the characteristics. As a result, the variation between them is eliminated at time t 01.
• the difference between the both-end voltage of power storage element 1 having the third voltage from the bottom of the variation width and the current both-end voltage of power storage element 1 having the lowest voltage of the variation width is the time.
• the control unit 10 turns off the discharge switch 9 connected to the power storage device 1 having the third voltage from the bottom.
• this storage element 1 is only charged almost after time t02, but the voltage across storage element 1 having the third voltage from the bottom at that time is the current (t02) Therefore, the variation between the two is eliminated at time t02, and thereafter increases with the same slope as shown in Fig. 9.
• the control unit 10 repeats the above operation until all the discharge switches 9 are turned off. As a result, the variation in the voltage across each storage element 1 that has been dispersed is gradually eliminated, and when all the discharge switches 9 are turned off at time tl, there is almost no variation after time tl. Each storage element 1 is continuously and efficiently charged in a state where the discharge current is reduced. At this time, since all the balance switches 5 remain on, the battery is charged without breaking the voltage balance.
• the variation width of the voltage across the storage element 1 is the width shown in FIG. 10 at the time tO at the time of activation, and charging is started in this state.
• the storage element 1 having the minimum voltage across the bottom (the voltage at the bottom of the variation width) is not connected to the discharge resistor 7, only the charging is performed from time tO.
• the other storage element 1 is connected to the discharge resistor 7 and a discharge current flows.
• the charge current is smaller than the discharge current here, the voltage at both ends thereof decreases with time. .
• the voltage across storage element 1 having the second voltage from the bottom of the variation width and the current voltage across storage element 1 having the lowest voltage in the variation width (time tOl)
• the difference is within the default value in a very short time.
• the operation after the predetermined condition is satisfied is exactly the same as in FIG. 9, and the control unit 10 turns off the discharge switch 9 connected to the storage element 1 having the second voltage from the bottom. To control to reduce the discharge current of the storage element 1 having the second voltage.
• the storage element 1 having the second voltage from the bottom is almost charged only after the time tOl, but the voltage across the storage element 1 having the second voltage from the bottom at that time is the minimum Since the voltage at both ends of the storage element 1 is almost equal to the current (tOl) voltage at both ends, the variation between the two is eliminated at time tOl, and as shown in FIG. 10, both rise with the same slope after time tOl.
• the controller 10 sequentially repeats the above operation until all the discharge switches 9 are turned off, so that all the discharge switches 9 are turned off at time tl. After time tl, as in FIG. 9, each storage element 1 is charged efficiently and continuously in a state where the discharge current with little variation is reduced. At this time, since all the balance switches 5 remain on, the battery is charged without breaking the voltage balance.
• control unit 10 includes all the discharge switches 9 and the batteries. Turn Lance switch 5 off. This suppresses unnecessary power consumption.
• control unit 10 has a power storage element having a voltage across the terminals at the time of charging.
• the power storage element 1 other than 1 is discharged with a large current, and the predetermined condition (the difference between the current both-end voltage of the power storage element 1 having the lowest voltage across both ends and the voltage across the other power storage element 1 is within the predetermined value) is satisfied. Each time the discharge switch 9 is turned off, the discharge current is reduced.
• the discharge resistor 7 having a resistance value smaller than that of the balance resistor 3 is provided in parallel with the storage element 1, and the storage elements 1 other than the storage element 1 having the lowest voltage at the time of charging are connected to the discharge resistor.
• the battery 7 discharges and sequentially balances the voltage, so that the voltage balance can be achieved in a short time even if the variation width of the voltage at both ends of the electricity storage element 1 is large.
• the device could be realized.
• the circuit configuration of the balance resistor 3 and the discharge resistor 7 of the power storage device 11 of FIG. 8 includes a balance resistor 3 connected in parallel for each power storage element 1 and a power storage unit as shown in FIG.
• a configuration including a discharge switch 9 connected between one end of the storage element 1 and the discharge resistor 7 may also be used.
• Other configurations are the same as those in FIG. By adopting such a configuration, the same effect as described in FIG. 4 of the first embodiment can be obtained.
• Embodiments 1 to 3 the power connected to power storage elements 1 in series. This may be a series-parallel connection according to the required power specifications.
• 12A and 12B show connection circuit diagrams of the storage element 1 and the voltage equalization circuit 2 in this case.
• FIG. 12A three storage elements 1 are connected in parallel to one voltage equalization circuit 2. Indicates the case. In this case, since the voltage across the three storage elements 1 in the parallel connection part of the series-parallel connection is equal, the voltage equalization circuit 2 does not need to be connected to each storage element 1, and the voltage across It is sufficient to connect to the common terminal of the electricity storage elements 1 having the same.
• FIG. 12B shows a case where three storage elements 1 connected in parallel to one voltage equalizing circuit 2 are connected in two stages in series.
• the voltage at both ends of the storage element 1 is different in the series connection portion, if the performance variation of the storage element 1 is small, the variation width of the voltage at both ends becomes small even when used in series connection.
• the voltage equalization circuit 2 does not necessarily need to be individually connected to each of the power storage elements 1, and a plurality of power storage elements 1 are grouped as one unit and one voltage equalization circuit 2 is connected to each of them. Also good.
• the voltage equalizing circuit 2 is composed of the balance resistor 3, the non-switch 5, the discharge resistor 7, and the discharge switch 9, and the force S is limited to this configuration.
• a circuit that can change the discharge current from the outside such as an electronic load circuit or a constant current circuit, may be used.
• the power storage device as an auxiliary power source at the time of restarting the engine has been described as an example.
• the present invention is not limited thereto, and each system such as an idling stop, an electric power steering, an electric turbo, a hybrid, an hybrid, etc.
• the present invention can also be applied to auxiliary power supplies for vehicles, general emergency backup power supplies as well as vehicles.
• the power storage device according to the present invention can balance the voltage of the power storage elements in a short time during charging, and is particularly useful as a power storage device for an auxiliary power source for vehicles or an emergency backup power source.

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• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Charge And Discharge Circuits For Batteries Or The Like (AREA)
• Secondary Cells (AREA)
• Electric Propulsion And Braking For Vehicles (AREA)

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• 2006
  • 2006-08-04 JP JP2006213168A patent/JP4940817B2/ja active Active
• 2007
  • 2007-07-25 KR KR1020087031012A patent/KR101024138B1/ko not_active Expired - Fee Related
  • 2007-07-25 CN CN2007800289467A patent/CN101501956B/zh active Active
  • 2007-07-25 EP EP07791256.6A patent/EP2043219B1/en active Active
  • 2007-07-25 US US12/307,169 patent/US8134337B2/en not_active Expired - Fee Related
  • 2007-07-25 WO PCT/JP2007/064538 patent/WO2008015933A1/ja not_active Ceased

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