JP5518001B2 - Battery control device - Google Patents

Description

  The present invention relates to an apparatus for controlling charge / discharge of an assembled battery in which a plurality of secondary batteries are connected in series.

  For example, in an electric vehicle, a high-voltage battery for driving a motor for driving and on-vehicle equipment is mounted. This high voltage battery is generally composed of a so-called assembled battery in which a plurality of secondary batteries such as lithium ion batteries are connected in series. In such an assembled battery, dischargeable electrical energy (hereinafter referred to as “discharge capacity”) varies among batteries due to variations in characteristics of the batteries. In the case of a secondary battery, the battery life is reduced due to overcharge or overdischarge. Therefore, if one of the batteries constituting the assembled battery is in a charged or discharged state, the entire assembled battery is charged. It is necessary to stop the discharge operation.

  For this reason, at the time of discharging, when the battery having the smallest discharge capacity completes discharging, the discharging operation of the entire assembled battery is stopped in a state where discharging of other batteries is not completed. On the other hand, at the time of charging, the battery that has not been completely discharged at the time of discharging is first charged before the battery that has been completely discharged at the time of discharging is completed, and the charging operation of the entire assembled battery is stopped at this point. . When such an operation is repeated, a battery having a small discharge capacity is always insufficiently charged, and the discharge capacity of the assembled battery as a whole decreases.

  As a solution to the above problems, a series circuit of switching elements and resistors is connected in parallel with each battery constituting the assembled battery, and the conduction / non-conduction of the switching elements is controlled according to the state of charge of each battery. Conventionally, a method has been proposed (see, for example, Patent Document 1). According to this method, for a battery having a high voltage, the switching element is turned on and charging is suppressed, and for a battery having a low voltage, the switching element is turned off and charging is performed preferentially. Thereby, each battery can be charged equally and it can suppress that the discharge capacity of the whole assembled battery falls.

  On the other hand, if charging / discharging in a state where the temperature of the battery is high, the battery may be destroyed, so the temperature of the battery is detected, and if the detected temperature is equal to or higher than the reference value, charging / discharging may be prohibited. Traditionally done. Patent Document 2 describes that in a charger, charging control is performed in consideration of not only the temperature of the battery itself but also the ambient temperature. In Patent Document 2, a battery temperature detection element that detects the temperature of the assembled battery and an ambient temperature detection element that detects the ambient temperature of the charger are provided, and the output of the battery temperature detection element is based on the output of the ambient temperature detection element. By correcting this, malfunction of the charger due to fluctuations in ambient temperature is prevented.

JP-A-8-19188 JP-A-8-308131

  When the battery constituting the assembled battery is discharged, a current flows through the discharge resistor in the discharge circuit, and the discharge resistor generates heat. For this reason, when the discharge temperature is controlled by measuring the temperature of the battery, the temperature measurement value of each battery is higher than the actual battery temperature due to the influence of heat of the discharge resistance. As a result, although the temperature of the battery itself is in the normal range, the battery temperature is determined to be abnormal, and the discharge operation stops due to a malfunction.

  As a countermeasure against this, there is a method of correcting the temperature measurement value of the battery by providing an ambient temperature detection element as in Patent Document 2, but the present invention is caused by the heat generated in the discharge circuit without using the ambient temperature detection element. The problem is to prevent malfunctions that occur.

  In the present invention, a voltage detection unit that detects each voltage of a plurality of secondary batteries constituting the assembled battery, and a current path that is provided corresponding to each of the secondary batteries and discharges the secondary battery are formed. A discharge circuit that has a temperature detection element, a temperature measurement unit that measures the temperature of each secondary battery based on the output of the temperature detection element, a circuit board on which the discharge circuit and the temperature detection element are mounted, and a voltage The voltage detected by the detection unit is transmitted to the host device, the discharge request is received from the host device, the discharge circuit corresponding to the secondary battery requested to be discharged is put into an operating state, and the secondary battery is discharged. When the temperature of the secondary battery measured by the temperature control unit and the discharge control means for controlling the temperature is equal to or higher than the reference temperature, the discharge circuit corresponding to the secondary battery is deactivated and discharge is prohibited. A set having discharge inhibiting means In the control device of the pond, the secondary battery after starting discharge, based on the elapsed time from the start of discharge is provided a correction means for correcting the temperature measurements of each secondary battery calculated by the temperature measurement unit.

  In this way, even if the discharge circuit generates heat in the discharge circuit due to the discharge of the secondary battery, and the temperature detection element is affected by this heat generation, the temperature measurement value of each cell is corrected, so heat is generated from the temperature measurement value. The effect of is removed. Therefore, accurate discharge control for each cell can be performed, and it is possible to prevent the discharge of the cells whose temperature is in the normal range from stopping. Further, since the temperature rise in the discharge circuit is obtained by calculation based on the elapsed time from the start of discharge, temperature correction can be performed without providing an ambient temperature detecting element.

  In the present invention, the correction means further corrects the temperature measurement value of each secondary battery calculated by the temperature measurement unit based on the elapsed time from the discharge stop after the secondary battery stops discharging. May be.

  Further, in the present invention, the correction means calculates the temperature rise in each discharge circuit based on the elapsed time from the start or stop of discharge, and calculates a total value obtained by summing the respective temperature rises. The temperature measurement value may be corrected by subtracting the total value from the measurement value.

  Further, in the present invention, a voltage detection unit that detects each voltage of a plurality of secondary batteries constituting the assembled battery, and a current path that is provided corresponding to each of the secondary batteries and discharges the secondary battery A discharge circuit that forms a temperature detection unit, a temperature measurement unit that measures the temperature of each secondary battery based on the output of the temperature detection element, a circuit board on which the discharge circuit and the temperature detection element are mounted, The charge / discharge control means for controlling the charging and discharging of each secondary battery based on the voltage detected by the voltage detection unit, and when the temperature of the secondary battery measured by the temperature measurement unit is equal to or higher than the reference temperature. In the battery pack control device comprising the discharge prohibiting means for prohibiting discharge by disabling the discharge circuit corresponding to the secondary battery, the elapsed time from the start of discharge after the secondary battery starts discharging Calculated by the temperature measurement unit based on The temperature measurement value of each secondary battery calculated by the temperature measurement unit based on the elapsed time from the discharge stop after the secondary battery stopped discharging after correcting the temperature measurement value of each secondary battery Correction means for correcting the above is provided.

  According to the present invention, it is possible to correct the temperature measurement value of the secondary battery without using the ambient temperature detection element, and to prevent malfunction due to heat generation of the discharge circuit.

It is a block diagram showing an embodiment of the present invention. It is a block diagram of a temperature measurement part. It is a top view showing arrangement of elements on a circuit board. It is a flowchart showing the process sequence in a charging / discharging control unit and a voltage and temperature measurement unit. It is a flowchart showing the procedure of the temperature correction process at the time of discharge operation. It is a flowchart showing the procedure of the temperature correction process at the time of a discharge stop. It is a graph showing the change of the temperature measurement value at the time of discharge operation. It is a graph showing the change of the temperature measurement value at the time of discharge stop.

  Embodiments of the present invention will be described with reference to the drawings. In the drawings, the same parts are denoted by the same reference numerals. Below, the case where this invention is applied to the assembled battery mounted in an electric vehicle is mentioned as an example.

  First, the configuration of the embodiment will be described with reference to FIG. In FIG. 1, a plurality of secondary batteries B1 to Bn are connected in series to form a battery pack 40. Hereinafter, the individual secondary batteries B1 to Bn are referred to as “cells”. As a system for controlling charging / discharging of the assembled battery 40, a voltage / temperature measurement unit 10, a charging / discharging control unit 20, and a charging unit 30 are provided. In the present embodiment, the voltage / temperature measurement unit 10 constitutes an assembled battery control device according to the present invention.

  The voltage / temperature measurement unit 10 includes a control unit 1, a voltage detection unit 2, discharge circuits 31 to 3 n (collectively represented by reference numeral 3), a temperature measurement unit 4, and a connection terminal T.

  The control unit 1 includes a CPU, a memory, and the like, and performs communication with the voltage detection unit 2 and also performs communication with the charge / discharge control unit 20. The controller 1 constitutes discharge control means, discharge inhibition means, and correction means in the present invention.

  The voltage detection unit 2 includes an analog-digital converter and the like, detects the voltages V1 to Vn of the cells B1 to Bn, converts these voltages V1 to Vn into digital values, and outputs them to the control unit 1. Further, the voltage detection unit 2 outputs discharge control signals P1 to Pn for driving or stopping the discharge circuits 31 to 3n based on a command from the control unit 1.

  The discharge circuits 31 to 3n are provided between the voltage detection unit 2 and the connection terminal T corresponding to the cells B1 to Bn. Since each discharge circuit has the same configuration, the discharge circuit 31 will be described here. The discharge circuit 31 includes a switching element Q1 and a discharge resistor R1. The switching element Q1 is composed of, for example, a field effect transistor (FET).

  One end of the discharge resistor R1 is connected to the drain of the switching element Q1, and the other end of the discharge resistor R1 is connected to the positive electrode of the cell B1 via the line L1 and the connection terminal T. The source of the switching element Q1 is connected to the negative electrode of the cell B1 via the line L2 and the connection terminal T. As a result, a discharge path is formed from the positive electrode of the cell B1 to the negative electrode of the cell B1 via the discharge resistor R1 and the switching element Q1. A discharge control signal P1 is applied from the voltage detection unit 2 to the gate of the switching element Q1 via a resistor.

  As shown in FIG. 2, the temperature measurement unit 4 includes a plurality of temperature detection elements 5 and one microcomputer 6. The temperature detection element 5 is composed of an element such as a thermistor whose resistance value changes with a change in temperature. The microcomputer 6 calculates the temperature based on the output of each temperature detection element 5 and sends the calculation result to the control unit 1 as a temperature measurement value.

  The cells B1 to Bn are made of, for example, a lithium ion battery, and the positive electrode and the negative electrode of each cell are connected to a pair of terminals T. Then, the voltages V1 to Vn of the cells B1 to Bn are input to the voltage detection unit 2 via the lines L1 to Ln.

  The charge / discharge control unit 20 is a host device that controls charge control and discharge control for the cells B1 to Bn, and includes a microcomputer (not shown). The charge / discharge control unit 20 gives a command to the voltage / temperature measurement unit 10 and the charge unit 30 when the cell needs to be charged based on the information acquired from the voltage / temperature measurement unit 10, and the cell needs to be discharged. In this case, a command is given to the voltage / temperature measurement unit 10. The charge / discharge control unit 20 constitutes charge / discharge control means in the present invention.

  The charging unit 30 is a charging device for charging the cells B1 to Bn with a constant voltage, the input side is connected to the charge / discharge control unit 20, and the output side is connected to the positive electrode of the cell B1. The charging unit 30 includes a constant voltage circuit, a voltage detection unit, a control unit, and the like (not shown).

  As shown in FIG. 3, the discharge resistors R <b> 1 to Rn, the temperature detection element 5, and the connection terminal T of the discharge circuit 3 are mounted on the circuit board K. On the circuit board K, the control unit 1 and the voltage detection unit 2 constituting the voltage / temperature measurement unit 10 are also mounted, but these are not shown in FIG. The temperature detection element 5 is provided for each connection terminal T, and is disposed close to each terminal T. Since the electrodes of the cells B1 to Bn are connected to the connection terminal T (see FIG. 1), the terminal T generates heat when the temperature of the cells B1 to Bn rises due to charge / discharge. Therefore, the temperature detection element 5 detects the temperatures of the cells B1 to Bn via the connection terminal T. Further, when the cells B1 to Bn are discharged, the discharge resistors R1 to Rn generate heat due to the current flowing through the discharge circuit 3. Since the discharge resistors R1 to Rn and the temperature detection element 5 are mounted on the circuit board K, the heat generated by the discharge resistors R1 to Rn is conducted through the circuit board K and reaches the temperature detection element 5.

  Next, the operation of the above embodiment will be described with reference to the flowchart of FIG.

  In step S <b> 1, the voltage of each cell is notified from the voltage / temperature measurement unit 10 to the charge / discharge control unit 20. Specifically, the voltages V1 to Vn of the cells B1 to Bn detected by the voltage detector 2 are sent to the controller 1, and the controller 1 notifies the charge / discharge control unit 20 of these voltages V1 to Vn.

  In step S <b> 2, the charge / discharge control unit 20 analyzes the cell voltage notified from the voltage / temperature measurement unit 10. Specifically, in the charge / discharge control unit 20, the voltages V1 to Vn of the cells B1 to Bn are compared with a predetermined reference voltage to determine whether the cell voltage is equal to or higher than the reference voltage.

  In step S3, cells whose cell voltage is equal to or higher than the reference voltage are extracted based on the analysis result in step S2, and these cells are determined as cells that need to be discharged.

  In step S4, a discharge request for a cell that needs to be discharged is transmitted from the charge / discharge control unit 20 to the voltage / temperature measurement unit 10 based on the determination result in step S3.

  In step S <b> 5, the voltage / temperature measurement unit 10 performs discharge control on the cell that has requested discharge. Specifically, when the control unit 1 receives a discharge request from the charge / discharge control unit 20, the control unit 1 sends a command based on the request to the voltage detection unit 2. In response to this command, the voltage detector 2 outputs a discharge control signal to a discharge circuit corresponding to a cell that needs to be discharged among the discharge circuits 31 to 3n. Thus, for example, in the discharge circuit 31, the H (High) level discharge control signal P1 is given to the gate of the switching element Q1, and the switching element Q1 is turned on. Then, a discharge path of positive electrode of cell B1 → connection terminal T → line L1 → discharge resistor R1 → switching element Q1 → line L2 → connection terminal T → negative electrode of cell B1 is formed, and cell B1 discharges through this discharge path. As a result, the voltage of the cell B1 decreases.

  In step S6, the cell temperature is measured by the temperature measuring unit 4. Specifically, in the temperature measurement unit 4, the microcomputer 6 (see FIG. 2) takes in the output of each temperature detection element 5, and calculates a temperature measurement value based on these. The calculated temperature measurement value is sent to the control unit 1. As described above, the temperature detection element 5 is affected not only by the temperatures of the cells B1 to Bn but also by the heat generated by the discharge resistors R1 to Rn during discharge. Therefore, the temperature measurement value calculated by the temperature measurement unit 4 reflects the temperature of both the cell and the discharge resistance.

  In step S7, the controller 1 performs temperature correction processing that is a feature of the present invention. In the temperature correction process, the temperature measurement value of each cell calculated by the temperature measurement unit 4 is corrected by the temperature increase due to heat generated by the heat radiation resistors R1 to Rn. Details of this correction will be described later.

  The above steps S1 to S7 are repeated between the voltage / temperature measurement unit 10 and the charge / discharge control unit 20 at a constant cycle.

  In the voltage / temperature measurement unit 10, the control unit 1 performs the temperature correction processing in step S <b> 7, and then compares the corrected temperature measurement value of each cell with a predetermined reference temperature. And about the cell whose temperature measured value is more than reference temperature, in order to prevent destruction, a command is sent from control part 1 to voltage detection part 2, and discharge operation is stopped. In this case, the voltage detector 2 outputs an L (Low) level discharge control signal. Thereby, for example, in the discharge circuit 31, the L level discharge control signal P1 is given to the gate of the switching element Q1, and the switching element Q1 is turned off. Therefore, the discharge path from the positive electrode of the cell B1 to the negative electrode of the cell B1 via the discharge resistor R1 and the switching element Q1 is interrupted, so that the discharge of the cell B1 is prohibited. On the other hand, for a cell whose temperature measurement value is lower than the reference temperature, the control unit 1 does not send a command to the voltage detection unit 2 and continues the discharge operation.

  Next, details of the temperature correction process in step S7 will be described with reference to the flowcharts of FIGS.

  FIG. 5 shows the procedure of the temperature correction process during the discharge operation. After the cell starts discharging, in step S10, an elapsed time from the start of discharging is calculated for the cell being discharged. This elapsed time is measured by a timer provided in the control unit 1.

In step S11, based on the elapsed time calculated in step S10, the temperature rise of the discharge circuit 3 corresponding to the cell at that time is calculated. This temperature rise is based on the heat generation of the discharge resistance due to the discharge current, and is calculated by the following equation.
ΔTi = Kr · [1-exp (−t / τ)] (1)
here,
ΔTi: temperature rise [i = 1, 2,... M (m is the number of cells being discharged)]
Kr: coefficient (maximum value of temperature rise due to heat generation of discharge resistance)
t: Elapsed time τ: Time until the temperature rise becomes 63.2% of the maximum value. From equation (1), during the discharge operation, the temperature rise ΔTi increases with the elapsed time t.

  In step S12, it is determined whether or not the temperature increase calculation processing in step S11 has been completed for all (m) discharge circuits 3 corresponding to the cells being discharged. If the determination result is NO, steps S10 and S11 are executed again, and the temperature rise is calculated for the next discharge circuit. If the determination result is YES, the process proceeds to step S13.

In step S13, the temperature rise ΔTi of each discharge circuit calculated in step S11 is summed to obtain a total value. The total value Tsum is calculated by the following equation.
Tsum = ΔT1 + ΔT2 +... + ΔTm (2)
As described with reference to FIG. 3, the heat generated by the discharge resistance during cell discharge is conducted through the circuit board K and reaches the temperature detection element 5. Therefore, when a plurality of discharge resistances generate heat, the heat of each discharge resistance affects one temperature detection element 5, so that the temperature rise at each discharge resistance as shown in Equation (2). Sum the minutes. This total value Tsum becomes a correction value when performing temperature correction.

In step S14, the temperature measurement value of each cell obtained in step S6 of FIG. 4 is corrected using the total value Tsum for the temperature increase calculated in step S13. That is, the correction temperature Tc of each cell is calculated by the following equation.
Tc = temperature measurement value−Tsum (3)

  The correction temperature Tc calculated in this way is obtained by removing the influence of heat generation at the discharge resistors R1 to Rn from the temperature measurement value calculated by the temperature measurement unit 4. That is, the correction temperature Tc substantially represents the actual temperature of each cell. Therefore, the correction temperature Tc is compared with the reference temperature as described above. If the correction temperature Tc is equal to or higher than the reference temperature, the discharge operation is stopped. If the correction temperature Tc is lower than the reference temperature, the discharge operation is continued. Let Thus, accurate discharge control can be performed on each cell without being affected by heat generated by the discharge resistance. Therefore, it is possible to prevent a malfunction such as the discharge operation of the cell whose temperature is in the normal range being stopped.

  FIG. 7 is a graph showing an example of a change in the temperature measurement value during the discharge operation. In this example, the cell temperature before the start of discharge is 25 ° C. When the discharge is started, a current flows through the discharge resistors R1 to R4, and the temperature of each resistor rises as illustrated. For this reason, the temperature measurement value of the cell by the temperature measuring unit 4 rises as shown by the thick solid line under the influence of the temperature rise of the discharge resistors R1 to R4.

This temperature measurement value is the temperature of the cell at 25 ° C., the temperature rise a1 at the discharge resistor R1, the temperature rise a2 at the discharge resistor R2, the temperature rise a3 at the discharge resistor R3, and the temperature at the discharge resistor R4. It is a value obtained by adding the increase a4. Therefore, when the total value of the temperature rise at each discharge resistance is subtracted from the temperature measurement value, the correction temperature Tc is
Tc = temperature measurement value− (a1 + a2 + a3 + a4) = 25 ° C.
And calculated as the actual temperature of the cell.

  Next, temperature correction when discharge is stopped will be described. FIG. 6 shows the procedure of the temperature correction process when the discharge is stopped. After the cell has stopped discharging, in step S20, the elapsed time from the stop of the discharge is calculated for the cell in which the discharge has stopped. This elapsed time is measured by a timer provided in the control unit 1.

In step S21, based on the elapsed time calculated in step S20, the temperature rise of the discharge circuit corresponding to the cell at that time is calculated. This temperature rise is calculated by the following equation.
ΔTi = Kr · exp (−t / τ) (4)
here,
ΔTi: Temperature rise [i = 1, 2,... M (m is the number of cells that have stopped discharging)]
Kr: coefficient (maximum value of temperature rise due to heat generation of discharge resistance)
t: Elapsed time τ: Time until the temperature rise becomes 63.2% of the maximum value. From equation (4), when the discharge is stopped, the temperature rise ΔTi decreases with the elapsed time t.

  In step S22, it is determined whether or not the temperature increase calculation processing in step S21 has been completed for all (m) discharge circuits 3 corresponding to the cells where the discharge has stopped. If the determination result is NO, steps S20 and S21 are executed again, and the temperature rise is calculated for the next discharge circuit. If the determination result is YES, the process proceeds to step S23.

In step S23, the temperature rise ΔTi of each discharge circuit calculated in step S21 is added to obtain a total value. The total value Tsum is calculated by the following equation.
Tsum = ΔT1 + ΔT2 +... + ΔTm (5)
Also in this case, since the heat of each discharge resistor affects one temperature detection element 5, the temperature rises at the respective discharge resistors are summed. This total value Tsum becomes a correction value when performing temperature correction.

In step S24, the temperature measurement value is corrected as in step S14 of FIG. That is, the correction temperature Tc of each cell is calculated by the following equation using the total value Tsum for the temperature increase calculated in step S23.
Tc = temperature measurement value-Tsum (6)
Also in this case, the correction temperature Tc substantially represents the actual temperature of each cell. Therefore, by comparing the correction temperature Tc with the reference temperature, it is possible to perform accurate charge control for each cell, and it is possible to prevent malfunctions such as cells not being charged in the normal temperature range.

  FIG. 8 is a graph showing an example of a change in the measured temperature value when the discharge is stopped. When the discharge is stopped, no current flows through the discharge resistors R1 to R4, and the temperature of each resistor decreases as shown in the figure. For this reason, the measured temperature value of the cell by the temperature measuring unit 4 falls as shown by the thick solid line under the influence of the temperature drop of the discharge resistors R1 to R4.

This temperature measurement value is the temperature of the cell at 25 ° C., the temperature rise b1 at the discharge resistor R1, the temperature rise b2 at the discharge resistor R2, the temperature rise b3 at the discharge resistor R3, and the temperature at the discharge resistor R4. It is a value obtained by adding the increase b4. Therefore, when the total value of the temperature rise at each discharge resistance is subtracted from the temperature measurement value, the correction temperature Tc is
Tc = temperature measurement value− (b1 + b2 + b3 + b4) = 25 ° C.
And calculated as the actual temperature of the cell.

  As described above, in this embodiment, the temperature rise in the discharge resistance is calculated based on the elapsed time from the start or stop of discharge of the cell. Then, the temperature measurement value is corrected by subtracting the total value of the temperature increase from the temperature measurement value of each cell measured by the temperature measurement unit 4. For this reason, the influence of heat is removed from the temperature measurement value of each cell, and accurate charge / discharge control can be performed. Further, since the temperature rise of the discharge resistance is calculated based on the elapsed time from the start or stop of discharge, temperature correction can be performed without providing an ambient temperature detection element.

  Note that if the power supply of the voltage / temperature measurement unit 10 is turned off while the discharge starts and the temperature of the discharge resistance is rising, the discharge circuit 3 does not operate and the temperature of the discharge resistance decreases. In this case, even if the power supply of the voltage / temperature measurement unit 10 is turned off, the power supply of the charge / discharge control unit 20 that is the host device is kept on. For this reason, when the voltage / temperature measurement unit 10 is turned on again, the voltage / temperature measurement unit 10 does not know the time during which the power was off (hereinafter referred to as “power-off time”). The control unit 20 can count the power-off time. Accordingly, if the power / off control unit 20 notifies the voltage / temperature measurement unit 10 of the power-off time when the power is turned on again, the voltage / temperature measurement unit 10 side will drop the temperature during the period when the power is off. Minutes can be calculated to determine the exact temperature rise.

  In the present invention, various embodiments other than those described above can be adopted. For example, in the above-described embodiment, only one voltage / temperature measurement unit 10 is provided. However, a plurality of voltage / temperature measurement units 10 are provided, and these are collectively managed by one charge / discharge control unit 20. Such a configuration may be adopted.

  In the above embodiment, the voltage / temperature measurement unit 10 and the charge / discharge control unit 20 are provided as separate units. However, they may be configured as one unit. That is, the assembled battery control device according to the present invention may include a charge / discharge control means.

  In the above embodiment, the temperature measurement value of each cell is calculated by the microcomputer 6 provided in the temperature measurement unit 4. However, the microcomputer 6 is omitted, and the temperature measurement value of each cell is calculated by the control unit 1. You may make it calculate. In this case, the control unit 1 and the temperature detection element 5 constitute a temperature measurement unit.

  Moreover, in the said embodiment, although the example which provided the temperature measuring element 5 in proximity to the connection terminal T to which the cells B1 to Bn are connected was given, the heat of the cells B1 to Bn separately from the connection terminal T. The temperature measurement element 5 may be provided by providing a heat conducting member (not shown) that transmits the heat and in proximity to the member or in contact with the member.

  Furthermore, although the example which applied this invention to the assembled battery mounted in an electric vehicle was given in the said embodiment, this invention is applicable also to the assembled battery used for uses other than an electric vehicle.

DESCRIPTION OF SYMBOLS 1 Control part 2 Voltage detection part 3 Discharge circuit 4 Temperature measurement part 5 Temperature detection element 10 Voltage / temperature measurement unit 20 Charge / discharge control unit 30 Charging unit 40 Battery assembly B1-Bn Secondary battery K Circuit board Q1-Qn Switching element R1 ~ Rn Discharge resistance

Claims (4)

A voltage detection unit for detecting each voltage of a plurality of secondary batteries constituting the assembled battery;
A discharge circuit provided corresponding to each of the secondary batteries, and forming a current path when the secondary battery discharges;
A temperature measurement unit having a temperature detection element and measuring the temperature of each secondary battery based on the output of the temperature detection element;
A circuit board on which the discharge circuit and the temperature detection element are mounted;
The voltage detected by the voltage detection unit is transmitted to the host device, the discharge request is received from the host device, the discharge circuit corresponding to the secondary battery requested to be discharged is put into an operating state, and the secondary Discharge control means for controlling the battery to discharge;
A discharge prohibiting means for prohibiting discharge by disabling the discharge circuit corresponding to the secondary battery when the temperature of the secondary battery measured by the temperature measuring unit is equal to or higher than a reference temperature; In the battery pack control device,
After the secondary battery starts discharging, correction means for correcting a temperature measurement value of each secondary battery calculated by the temperature measuring unit based on an elapsed time from the start of discharging is provided. Control device for battery pack. In the control apparatus of the assembled battery of Claim 1,
The correction means further corrects the temperature measurement value of each secondary battery calculated by the temperature measurement unit based on an elapsed time from the discharge stop after the secondary battery stops discharging. A control device for a battery pack. In the control apparatus of the assembled battery of Claim 1 or Claim 2,
The correction means calculates a temperature rise in each discharge circuit based on the elapsed time, calculates a total value obtained by summing the temperature rises, and subtracts the total value from the temperature measurement value. The assembled battery control apparatus corrects the temperature measurement value by the following. A voltage detection unit for detecting each voltage of a plurality of secondary batteries constituting the assembled battery;
A discharge circuit provided corresponding to each of the secondary batteries, and forming a current path when the secondary battery discharges;
A temperature measurement unit having a temperature detection element and measuring the temperature of each secondary battery based on the output of the temperature detection element;
A circuit board on which the discharge circuit and the temperature detection element are mounted;
Charge / discharge control means for controlling charging and discharging of each secondary battery based on the voltage detected by the voltage detection unit;
A discharge prohibiting means for prohibiting discharge by disabling the discharge circuit corresponding to the secondary battery when the temperature of the secondary battery measured by the temperature measuring unit is equal to or higher than a reference temperature; In the battery pack control device,
After the secondary battery starts discharging, the temperature measurement value of each secondary battery calculated by the temperature measuring unit is corrected based on the elapsed time from the start of discharging, and the secondary battery stops discharging. And a correction means for correcting the temperature measurement value of each secondary battery calculated by the temperature measurement unit based on the elapsed time from the stop of discharge.

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