Battery control device and vehicle control device

Abstract

A calculation device (130) of a battery control device calculates a first resistance value (R1) of a secondary battery on the basis of the amount of change in a voltage value from a first time point (c1) to a second time point (c2) and the amount of change in a current value from the first time point to the second time point. Next, the change amount (beta) of the surface temperature is calculated on the basis of a first surface temperature (Ts1) in a range from the first time to the second time and a second surface temperature (Ts2) at a third time after a predetermined time (n) from the second time. Next, the amount of current of the secondary battery is calculated from the point in time at which the first surface temperature is measured to a third point in time (c3) at which the second surface temperature is measured. Then, the internal temperature of the secondary battery is estimated on the basis of the amount of change in the surface temperature and the amount of current. Then, on the basis of the internal temperature estimated with reference to the mapping table, a second resistance value (R2) in which the difference between the internal temperature and the surface temperature of the secondary battery is reflected is estimated. The degradation rate is calculated on the basis of the first resistance value and the second resistance value.

Description

TECHNICAL FIELD

[0001] The present application relates to a battery control device and a vehicle control device. BACKGROUND

[0002] Conventionally, a technique of determining deterioration of a secondary battery is known (see Patent Literature 1).

[0003] PRIOR ART DOCUMENT

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent Application Publication No. 2016-215836 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] In battery control and vehicle control, it is required to improve the calculation accuracy of the deterioration rate of a secondary battery.

[0008] TECHNICAL MEANS FOR SOLVING THE PROBLEMS

[0009] A battery control device of one embodiment of the present application includes a map table including data representing a relationship among a surface temperature, an internal temperature, and a resistance value of a secondary battery, and a calculation device that calculates a deterioration rate of the secondary battery on the basis of a change amount of each of a voltage value, a current value, and the surface temperature of the secondary battery. The calculation device calculates a first resistance value of the secondary battery on the basis of a change amount of the voltage value between a first time and a second time and a change amount of the current value between the first time and the second time. The calculation device calculates a change amount of the surface temperature on the basis of a first surface temperature within a range from the first time to the second time and a second surface temperature at a third time that has elapsed for a predetermined time from the second time. The calculation device calculates an amount of current of the secondary battery from a time at which the first surface temperature is measured to the third time at which the second surface temperature is measured. The calculation device estimates the internal temperature of the secondary battery on the basis of the change amount of the surface temperature and the amount of current, and estimates a second resistance value that reflects a difference between the internal temperature and the surface temperature of the secondary battery with reference to the relationship among the surface temperature, the internal temperature, and the resistance value stored in the map table and on the basis of the estimated internal temperature. The calculation device calculates the deterioration rate on the basis of the first resistance value and the second resistance value.

[0010] A vehicle control device of one embodiment of the present application is a vehicle control device including the battery control device. The vehicle control device controls a vehicle including the secondary battery and an electrical device that operates using electric power of the secondary battery.

[0011] Effects of Invention

[0012] According to the present application, in the battery control, the vehicle control, it is possible to improve the calculation accuracy of the deterioration rate of the secondary battery. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is a graph showing the temperature characteristics of the secondary battery 310, and is a graph overlappingly showing an example of the relationship between the internal temperature Ti and the surface temperature Ts of the secondary battery 310 at a prescribed current value of the secondary battery 310 at a prescribed current time n.

[0014] Figure 2 is a graph showing the temperature characteristics of the secondary battery 310, and is a graph overlappingly showing an example of the relationship between the temperature T and the resistance of the secondary battery 310 before deterioration, and the relationship between the temperature T and the resistance of the secondary battery 310 after deterioration.

[0015] Figure 3 is a block diagram showing the vehicle 1 of the vehicle control device 10 in which the battery control device 100 according to the embodiment is installed.

[0016] Figure 4 is a block diagram showing the battery control device 100.

[0017] Figure 5 is data showing the relationship between the value obtained by squaring the current value of the secondary battery 310 at a prescribed current time n and the temperature change amount β of the surface temperature Ts of the secondary battery 310 at the prescribed current time n for each of a plurality of SOC of the secondary battery 310, which is included in the mapping table 120. DETAILED DESCRIPTION

[0018] (Temperature characteristics of the secondary battery 310 with respect to the embodiment)

[0019] Reference Figure 1 and Figure 2 The temperature characteristics of the secondary battery 310 are described.

[0020] Figure 1 is a graph showing the temperature characteristics of the secondary battery 310, and is a graph overlappingly showing an example of the relationship between the internal temperature Ti and the surface temperature Ts of the secondary battery 310 at a prescribed current time n.

[0021] When the secondary battery 310 is energized, a charge-discharge body contained in the secondary battery 310 generates heat due to an electrochemical reaction. The charge-discharge body is, for example, a wound body in which a positive electrode and a negative electrode are wound with a separator interposed therebetween. The charge-discharge body can also be a stacked body in which a positive electrode and a negative electrode are stacked with a separator interposed therebetween in multiple layers. In the secondary battery 310, the charge-discharge body is housed in an outer packaging body. The outer packaging body is, for example, a can and a lid. The outer packaging body can also be a laminated film. Heat generated by the charge-discharge body moves from the inside of the secondary battery 310 to the surface of the secondary battery 310. The surface of the secondary battery 310 is the surface of the lid, the can. The charge-discharge body radiates heat from the inside of the secondary battery 310 to the surface of the secondary battery 310.

[0022] Therefore, when the secondary battery 310 is energized, a difference is generated between the internal temperature and the external temperature of the secondary battery 310 until the secondary battery 310 is in a thermal equilibrium state. Therefore, as shown in FIG. 1, an internal temperature curve L1 representing the internal temperature Ti of the secondary battery 310 and a surface temperature curve L2 representing the surface temperature Ts of the secondary battery 310 do not overlap with each other in a region in which the secondary battery 310 is not in the thermal equilibrium state. At any time in the region in which the secondary battery 310 is not in the thermal equilibrium state, the internal temperature Ti of the secondary battery 310 represented by the internal temperature curve L1 is higher than the surface temperature Ts of the secondary battery 310 represented by the surface temperature curve L2. Figure 1

[0023] In the secondary battery 310, Figure 1 at time 0, the internal temperature curve L1 overlaps with the surface temperature curve L2. That is, at time 0, the secondary battery 310 becomes in the thermal equilibrium state. At time 0, since the secondary battery 310 is not energized, the charge-discharge body contained in the secondary battery 310 does not generate heat. Therefore, at time 0, the internal temperature Ti of the secondary battery 310 coincides with the surface temperature Ts. The internal temperature Ti of the secondary battery 310 coincides with the surface temperature Ts is premised on the fact that the thermal influence of the ambient environment of the secondary battery 310 on the secondary battery 310 is sufficiently small.

[0024] In the secondary battery 310, Figure 1 ​The surface temperature Ts at any time within the range from the first time c1 to the second time c2 is defined as the first surface temperature Ts1. The first surface temperature Ts1 is, for example, the surface temperature Ts of the secondary battery 310 at the second time c2. The first surface temperature Ts1 can be the first time c1 or an intermediate time between the first time c1 and the second time c2. The time from the first time c1 to the second time c2 is, for example, tens of milliseconds. As described later, during the time from the first time c1 to the second time c2, the battery control device 100 calculates the first resistance value R1 of the secondary battery 310. At any time within the range from the first time c1 to the second time c2, the internal temperature Ti of the secondary battery 310, represented by the internal temperature curve L1, is higher than the surface temperature Ts of the secondary battery 310, represented by the surface temperature curve L2.

[0025] In the secondary battery 310, from Figure 1 The surface temperature Ts of the second surface, which occurs after a predetermined time n from the second time c2, is defined as the second surface temperature Ts2. The predetermined time n is, for example, several seconds to tens of seconds. As described later, during the predetermined time n from the moment when the first surface temperature Ts1 of the secondary battery 310 is measured (any moment within the range from the first time c1 to the second time c2) to the third time c3, the battery control device 100 calculates the current SI of the secondary battery 310. The current SI of the secondary battery 310 is the cumulative current, which is the value of the square of the current multiplied by the predetermined time n (I0). 2 ×n). At the third time c3, the internal temperature Ti of the secondary battery 310, represented by the internal temperature curve L1, is higher than the surface temperature Ts of the secondary battery 310, represented by the surface temperature curve L2.

[0026] In the secondary battery 310, Figure 1 The difference between the second surface temperature Ts2 and the first surface temperature Ts1 is defined as the change β. Since the secondary battery 310 is energized for a specified time n, the second surface temperature Ts2 is higher than the first surface temperature Ts1. That is, the change β is the increase in the surface temperature Ts of the secondary battery 310 over the specified time n, equivalent to the surface temperature difference of the secondary battery 310. As described later, the battery control device 100 calculates a correction value α for the surface temperature Ts of the secondary battery 310 based on the change β of the surface temperature Ts and the current SI.

[0027] In the secondary battery 310, Figure 1 At the fourth time point c4, the internal temperature curve L1 and the surface temperature curve L2 overlap. That is, at the fourth time point c4, the secondary battery 310 is in thermal equilibrium.

[0028] Figure 2is a graph showing the temperature characteristics of the secondary battery 310, and is an example of a graph in which the relationship between the temperature T and the resistance of the secondary battery 310 before deterioration and the relationship between the temperature T and the resistance of the secondary battery 310 after deterioration are shown superimposed.

[0029] In Figure 2 , as the resistance curve L3 before deterioration, the relationship between the temperature T and the resistance value R of the secondary battery 310 before deterioration at an arbitrary time is shown. The secondary battery 310 before deterioration corresponds to, for example, a new secondary battery 310. In Figure 2 , as the resistance curve L4 at the time of deterioration, the relationship between the temperature T and the resistance value R of the secondary battery 310 before deterioration at a prescribed time is shown. The resistance of the secondary battery 310 increases due to deterioration. The resistance is, for example, the internal resistance of the secondary battery 310. The internal resistance is, for example, the DCR (Direct Current Resistance). Even if the secondary battery 310 is energized under the same conditions, the resistance value R of the secondary battery 310 after deterioration is larger than the resistance value R of the secondary battery 310 before deterioration. The temperature of the secondary battery 310 is assumed to be the temperature of the charge-discharge body provided inside the secondary battery 310. Therefore, in order to calculate the resistance value R of the secondary battery 310, it is preferable to calculate not from the surface temperature Ts of the secondary battery 310, but from the internal temperature Ti estimated from the surface temperature Ts of the secondary battery 310.

[0030] The SOH of the secondary battery 310 depends on the temperature of the charge-discharge body. The SOH (State Of Health) is the deterioration rate of the secondary battery 310. The temperature of the charge-discharge body is not the surface temperature Ts of the secondary battery 310, but is close to the internal temperature Ti of the secondary battery 310. As described later, in the embodiment, in order to improve the calculation accuracy of the SOH of the secondary battery 310, the internal temperature Ti of the secondary battery 310 is estimated with high accuracy from the measured surface temperature Ts of the secondary battery 310.

[0031] (Configuration of the vehicle 1 of the embodiment)

[0032] The configuration of the vehicle 1 according to the vehicle control device 10 including the battery control device 100 of the embodiment will be described with reference to Figures 1 to 5 The battery control device 100 and the vehicle control device 10 of the embodiment will be described.

[0033] Figure 3 is a block diagram showing the vehicle 1 provided with the vehicle control device 10 including the battery control device 100 of the embodiment. Figure 4 is a block diagram showing the battery control device 100. Figure 5The data contained in the mapping table 120 is data representing the relationship between the squared value of the current value of the secondary battery 310 after a specified energizing time n and the temperature difference of the surface temperature Ts of the secondary battery 310 during the specified energizing time n for each of the multiple SOCs of the secondary battery 310.

[0034] (Composition of Vehicle 1)

[0035] Vehicle 1 may be composed of, for example, a hybrid electric vehicle. A hybrid electric vehicle may be, for example, a HEV (Hybrid Electric Vehicle) or a PHEV (Plug-in Hybrid Electric Vehicle). Hybrid electric vehicles include heavy-duty hybrid electric vehicles with an output voltage of, for example, several hundred V, and light-duty hybrid electric vehicles with an output voltage of, for example, 48 V. Vehicle 1 may also be composed of an EV (Electric Vehicle).

[0036] In the case of vehicle 1 being a HEV (Hybrid Electric Vehicle), vehicle 1 is equipped with a motor 600 as an electrical device for driving vehicle 1 and an engine 700 as an internal combustion engine. In the HEV, the power generated by the motor 600 and the engine 700 is transmitted to the tires. The motor 600 operates using electricity supplied from the battery pack 20. The HEV also includes a generator for charging the battery pack 300 of the battery pack 20. In the case of vehicle 1 being an EV (Electric Vehicle), vehicle 1 does not have an engine 700. In the EV, the power generated by the motor 600 is transmitted to the tires.

[0037] Vehicle 1 includes a battery control unit 100, a vehicle equipment control unit 200, a battery pack 300, a relay 400, a power converter 500, a motor 600, and an engine 700. In vehicle 1, the configuration including the battery control unit 100 and the vehicle equipment control unit 200 is referred to as the vehicle control unit 10. The vehicle control unit 10 includes the battery control unit 100. The vehicle control unit 10 controls the secondary battery 310 and the vehicle 1, which has electrical equipment that operates using power from the secondary battery 310. In vehicle 1, the configuration including the battery control unit 100 and the battery pack 300 is referred to as the battery pack 20. Hereinafter, the various configurations from the battery control unit 100 to the engine 700 of vehicle 1 will be described.

[0038] (Composition of the battery control device 100)

[0039] Reference Figures 1 to 5 Explain the structure of the battery control device 100.

[0040] The battery control device 100 is, for example, called a battery management system (BMS).Figure 4 As shown in FIG. 1, the battery control device 100 includes a sensor unit 110, a map table 120, and a calculation device 130. Hereinafter, each configuration of the sensor unit 110, the map table 120, and the calculation device 130 of the battery control device 100 will be described.

[0041] (Configuration of the sensor unit 110)

[0042] The sensor unit 110 measures the voltage value V, the current value I, and the temperature T of the secondary battery 310 included in the battery pack 300. As shown in FIG. 1, the sensor unit 110 includes a voltage measuring section 111, a current measuring section 112, and a temperature measuring section 113. Hereinafter, each configuration of the voltage measuring section 111, the current measuring section 112, and the temperature measuring section 113 of the sensor unit 110 will be described. Figure 4

[0043] (Configuration of the voltage measuring section 111)

[0044] The voltage measuring section 111 measures the voltage value V of the secondary battery 310. The voltage measuring section 111 is configured by, for example, a circuit that is combined with a battery voltage detection terminal, an electric wire, a resistor, a capacitor, and the like. The voltage measuring section 111 measures the voltage value of the secondary battery 310 via a bus bar that electrically connects one secondary battery 310 and another secondary battery 310. The battery voltage detection terminal is attached to the bus bar. Thus, the potential of the negative external terminal of one secondary battery 310 is measured, and the potential of the positive external terminal of another secondary battery 310 is measured. The voltage measuring section 111 measures the voltage value of the secondary battery 310 based on the difference between the potential of the positive external terminal and the potential of the negative external terminal of the secondary battery 310. The voltage value V of the secondary battery 310 corresponds to the open circuit voltage (OCV) of the secondary battery 310.

[0045] (Configuration of the current measuring section 112)

[0046] The current measuring section 112 measures the current value I of the secondary battery 310. The current measuring section 112 is configured in common with the circuit of the voltage measuring section 111. The voltage measuring section 111 calculates the current value I of the secondary battery 310 based on the current value that flows through the resistor of the voltage measuring section 111.

[0047] (Configuration of the temperature measuring section 113)

[0048] ​The temperature measuring section 113 measures the surface temperature Ts of the secondary battery 310. The temperature measuring section 113 is attached to the surface of the secondary battery 310. The surface of the secondary battery 310 is, for example, the surface of the lid of the secondary battery 310, and is the surface of a portion where no explosion valve or the like is formed. The temperature measuring section 113 is pressed into contact with the surface of the secondary battery 310 by a support member. The temperature measuring section 113 can also be joined to the surface of the secondary battery 310 by an adhesive. The temperature measuring section 113 is attached to all of the plurality of secondary batteries 310. The temperature measuring section 113 can also be attached to a part of the plurality of secondary batteries 310. In the case where the temperature measuring section 113 is attached to a part of the plurality of secondary batteries 310, the temperature measuring section 113, for example, takes the average of the surface temperatures Ts of the part of the secondary batteries 310 as the surface temperature Ts of the secondary battery 310.

[0049] (Configuration of the mapping table 120)

[0050] Referring to Figure 5 the configuration of the mapping table 120 will be described.

[0051] Figure 5 is data included in the mapping table 120, and indicates, for each of a plurality of SOCs of the secondary battery 310, the relationship between the value obtained by squaring the current value of the secondary battery 310 at a prescribed charging time n and the amount of change β in the temperature of the surface temperature Ts of the secondary battery 310 at the prescribed charging time n.

[0052] The mapping table 120 includes an OCV-SOC correlation table 121, Figure 5 a temperature correction table 122, and a resistance value correlation table 123, as shown in FIG. 1.

[0053] The OCV-SOC correlation table 121 is referred to by the SOC estimation section 131 of the arithmetic device 130, which will be described later. The OCV-SOC correlation table 121 is a table indicating the relationship between the OCV and the SOC. The OCV (Open Circuit Voltage) is the open circuit voltage of the secondary battery 310. The SOC (States Of Charge) is the charge rate of the secondary battery 310. For example, in the case of a secondary battery 310 such as a lithium ion secondary battery, the OCV and the SOC have a correlation relationship. Such a secondary battery 310 has a prescribed SOC corresponding to a prescribed OCV. That is, the secondary battery 310 has a relationship between the OCV and the SOC represented by a curve. Therefore, the secondary battery 310 can estimate the SOC corresponding thereto by operating the OCV.

[0054] The temperature correction table 122 is referred to by the internal temperature calculation section 133 of the arithmetic device 130 described later. In the temperature correction table 122, the relationship between the value after squaring the current value I of the secondary battery 310 for a prescribed on-time n of the secondary battery 310 (I 2 ×n) and the change amount β of the surface temperature Ts of the secondary battery 310 for the prescribed on-time n of the secondary battery 310 is indicated for each of a plurality of SOCs of the secondary battery 310. The temperature correction table 122 eliminates the influence of discharging and charging of the secondary battery 310 by using the value after squaring the current value I of the secondary battery 310. In the temperature correction table 122, the correction value α of the surface temperature Ts of the secondary battery 310 at the second time c2 corresponding to the change amount β of the surface temperature Ts of the secondary battery 310 is indicated. By adding the correction value α to the surface temperature Ts of the secondary battery 310 at the second time c2, the internal temperature Ti of the secondary battery 310 at the second time c2 is estimated.

[0055] The resistance value correlation table 123 is referred to by the second resistance calculation section 135 of the arithmetic device 130 described later. The resistance value correlation table 123 is a table indicating the relationship between the SOC of the secondary battery 310 and the resistance value (second resistance value R2) of the secondary battery 310 before deterioration corresponding to the internal temperature Ti of the secondary battery 310. The resistance value correlation table 123 indicates the relationship between the internal resistance of the secondary battery 310 before deterioration and the SOC, i.e., the internal resistance of the secondary battery 310 at the time of new product and the SOC.

[0056] (Configuration of the arithmetic device 130)

[0057] The arithmetic device 130 calculates the SOH of the secondary battery 310 from the change amounts of the voltage value V, the current value I, and the surface temperature Ts of the secondary battery 310.

[0058] The arithmetic device 130 includes an information processing device such as a CPU (Central Processing Unit), an ECU (Electronic Control Unit), an MPU (Micro Processing Unit), a DSP (Digital Signal Processor), and the like. The arithmetic device 130 includes a storage device (memory) such as a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The information processing device included in the arithmetic device 130 performs calculation according to a program and data stored in a recording device.

[0059] As Figure 4As shown, the operation device 130 includes a SOC estimation section 131, a delay block 132, an internal temperature operation section 133, a first resistance operation section 134, a second resistance operation section 135, a SOHR operation section 136, and a life prediction section 137. Hereinafter, each configuration of the operation device 130 from the SOC estimation section 131 to the life prediction section 137 will be described.

[0060] (Configuration of the SOC estimation section 131 of the operation device 130)

[0061] The SOC estimation section 131 of the operation device 130 estimates the SOC of the secondary battery 310 from the voltage value V of the secondary battery 310 measured by the voltage measurement section 111 of the sensor unit 110 and the OCV-SOC correlation table 121 of the map table 120. In a case where the voltage value V of the secondary battery 310 measured by the voltage measurement section 111 is defined as a defined voltage value, the SOC estimation section 131 first extracts an OCV equivalent to the defined voltage value in the OCV-SOC correlation table 121, and then derives the SOC of the OCV-SOC correlation table 121 corresponding to the extracted OCV. The SOC estimation section 131 estimates the SOC derived from the OCV-SOC correlation table 121 as the SOC of the secondary battery 310.

[0062] (Configuration of the delay block 132 of the operation device 130)

[0063] The delay block 132 of the operation device 130 inputs the second surface temperature Ts2 of the secondary battery 310 measured by the temperature measurement section 113 at the third time c3 shown in FIG. 6 to the internal temperature operation section 133. Figure 1

[0064] (Configuration of the internal temperature operation section 133 of the operation device 130)

[0065] The internal temperature operation section 133 of the operation device 130 operates the internal temperature Ti of the secondary battery 310 at the second time c2. The first surface temperature Ts1 shown in FIG. 5 is input from the temperature measurement section 113 to the internal temperature operation section 133. The first surface temperature Ts1 is, for example, the surface temperature Ts of the secondary battery 310 at the second time c2. The second surface temperature Ts2 shown in FIG. 6 is input from the temperature measurement section 113 to the internal temperature operation section 133 via the delay block 132. The second surface temperature Ts2 is the surface temperature Ts of the secondary battery 310 at the third time c3. The internal temperature operation section 133 operates the change amount β of the surface temperature Ts of the secondary battery 310 from the first surface temperature Ts1 and the second surface temperature Ts2. The change amount β is a value obtained by subtracting the first surface temperature Ts1 from the second surface temperature Ts2. Figure 1 Figure 1

[0066] ​​​The current value I is input from the current measuring unit 112 to the internal temperature calculation unit 133. The internal temperature calculation unit 133 calculates the value (I) obtained by squaring the current value I during the energizing time n of the secondary battery 310. 2 ×n). That is, the internal temperature calculation unit 133 calculates the current SI (I) of the secondary battery 310 from the time when the first surface temperature Ts1 of the secondary battery 310 is measured to the third time c3 when the second surface temperature Ts2 of the secondary battery 310 is measured. 2 ×n). The internal temperature calculation unit 133 calculates the change in surface temperature Ts of the secondary battery 310 by β and the current SI (I). 2 ×n), calculate the correction value α for the first surface temperature Ts1 of the secondary battery 310. For example... Figure 1 As shown, the value of adding the correction value α to the first surface temperature Ts1 at the second time c2 is equivalent to the internal temperature Ti of the secondary battery 310 at the second time c2. Alternatively, the correction value α can be omitted, and the surface temperature Ts of the secondary battery 310 can be multiplied, divided, or added to by a specified coefficient based on the change β of the surface temperature Ts of the secondary battery 310.

[0067] (The configuration of the first resistive arithmetic unit 134 of the arithmetic device 130)

[0068] The first resistance calculation unit 134 of the arithmetic device 130 calculates the first resistance value R1 of the secondary battery 310 based on the voltage value V and current value I of the secondary battery 310 input from the sensor unit 110. The first resistance value R1 corresponds to the internal resistance of the secondary battery 310 at the time of calculation. The internal resistance of the secondary battery 310 is, for example, equivalent to the DC resistance (DCR) of the secondary battery 310.

[0069] The first resistance calculation unit 134 according to Figure 1 The change in voltage V of the secondary battery 310, dV, from the first time c1 to the second time c2, and the change in current I, dI, from the first time c1 to the second time c2, are used to calculate the first resistance value R1 of the secondary battery 310. The change in voltage V, dV, is the difference between the voltage V of the secondary battery 310 at the second time c2 and the voltage V of the secondary battery 310 at the first time c1. The change in current I, dI, is the difference between the current I of the secondary battery 310 at the second time c2 and the current I of the secondary battery 310 at the first time c1. The time from the first time c1 to the second time c2 is, for example, set to tens of milliseconds. The time from the first time c1 to the second time c2 can be set from several milliseconds to hundreds of milliseconds, or even more than one second.

[0070] (Configuration of the second resistance calculation section 135 of the arithmetic device 130)

[0071] The second resistance calculation section 135 of the arithmetic device 130 calculates the resistance value (second resistance value R2) of the secondary battery 310 before deterioration. The second resistance value R2 corresponds to the internal resistance of the secondary battery 310 at the time of new. The second resistance calculation section 135 of the arithmetic device 130 calculates the second resistance value R2 of the secondary battery 310 from the SOC of the secondary battery 310 input from the SOC estimation section 131, the surface temperature Ts of the secondary battery 310 input from the internal temperature calculation section 133 and corrected by the correction value a, and the resistance value correlation table 123. The relationship among the SOC of the secondary battery 310, the surface temperature Ts of the secondary battery 310 (corrected to the internal temperature Ti by the correction value a), and the resistance value (second resistance value R2) of the secondary battery 310 before deterioration is indicated in the resistance value correlation table 123. That is, the second resistance calculation section 135 refers to the relationship among the surface temperature Ts, the internal temperature Ti, and the resistance value R of the secondary battery 310, and estimates the second resistance value R2 of the secondary battery 310 that reflects the difference between the internal temperature Ti and the surface temperature Ts of the secondary battery 310, from the estimated internal temperature Ti of the secondary battery 310.

[0072] (Configuration of the SOHR calculation section 136 of the arithmetic device 130)

[0073] The SOHR calculation section 136 of the arithmetic device 130 calculates the deterioration rate of the secondary battery 310 from the respective amounts of change in the voltage value V, the current value I, and the surface temperature Ts of the secondary battery 310. Specifically, the SOHR calculation section 136 calculates the deterioration rate of the secondary battery 310 from the first resistance value Rl of the secondary battery 310 calculated by the first resistance calculation section 134 and the second resistance value R2 of the secondary battery 310 calculated by the second resistance calculation section 135. As described above, the first resistance calculation section 134 refers to the amounts of change in the voltage value V and the current value I of the secondary battery 310 when calculating the first resistance value Rl. In addition, as described above, the second resistance calculation section 135 refers to the amount of change β in the surface temperature Ts of the secondary battery 310 when calculating the second resistance value R2.

[0074] The SOHR operation section 136, for example, operates the deterioration rate of the secondary battery 310 by dividing the first resistance value Rl by the second resistance value R2. The deterioration rate of the secondary battery 310 corresponds to the SOH (State Of Health). The SOH is represented by, for example, the deterioration rate of the resistance of the secondary battery 310. That is, the SOH is represented by, for example, the SOHR (State Of Health Based on Resistance). The resistance of the secondary battery 310 is the internal resistance of the secondary battery 310. Therefore, the SOHR operation section 136 operates the SOH as the SOHR, which is the rate of increase of the resistance of the secondary battery 310, from the first resistance value Rl of the secondary battery 310 and the second resistance value R2 of the secondary battery 310.

[0075] The SOHR operation section 136 of the operation device 130 can also be configured to operate the SOHC without operating the SOH. The SOHC (State Of Health based on Capacity) is the capacity deterioration rate of the secondary battery 310. In this configuration, the configurations of the first resistance operation section 134 and the second resistance operation section 135 are each changed to a configuration for operating the capacity of the secondary battery 310.

[0076] (Configuration of the life prediction section 137 of the operation device 130)

[0077] The life prediction section 137 of the operation device 130 predicts the life of the secondary battery 310 from the SOH. The life prediction section 137 predicts the life of the secondary battery 310 from the SOHR of the secondary battery 310 operated by the SOHR operation section 136. The life prediction section 137, for example, predicts the life of the secondary battery 310 from the amount of change in the SOHR of the secondary battery 310 operated by the SOHR operation section 136. In addition, the life prediction section 137 predicts the life of the secondary battery 310 from the SOHR of the secondary battery 310 operated by the SOHR operation section 136 and the usage history of the secondary battery 310. In addition, the life prediction section 137 predicts the life of the battery pack 300 from the SOHR of each of the secondary batteries 310 and the usage history of the battery pack 300, with the battery pack 300 including a plurality of secondary batteries 310.

[0078] (Configuration of the vehicle equipment control device 200)

[0079] Reference Signs Figure 3The configuration of the vehicle device control device 200 will be described. The vehicle device control device 200 controls the drive device of the vehicle 1. The vehicle device control device 200 includes an information processing device such as a CPU, an ECU, an MPU, a DSP, and the like. The vehicle device control device 200 includes a storage device such as a ROM, a RAM, and the like. The information processing device included in the vehicle device control device 200 controls in accordance with a program and data stored in the recording device. The information processing device and the recording device of the vehicle device control device 200 can be shared with the information processing device and the recording device of the battery control device 100. The drive device of the vehicle 1 includes a relay 400, a power converter 500, a motor 600, and an engine 700. The vehicle device control device 200 refers to the power information of the battery pack 300 output from the battery control device 100.

[0080] (Configuration of the battery pack 300)

[0081] Referring to Figure 3 The configuration of the battery pack 300 will be described. The battery pack 300 includes a plurality of secondary batteries 310. The plurality of secondary batteries 310 are connected in series, connected in parallel, or connected in series and in parallel through bus bars. The secondary battery 310 is, for example, a lithium ion battery. The power of the battery pack 300 is supplied to the motor 600 via the relay 400 and the power converter 500. The secondary battery 310 can be configured by a device having an electric storage function such as a nickel-hydrogen battery, an all-solid-state battery, a lead battery, and an electric double layer capacitor. The battery pack 300 can also be configured by one secondary battery 310.

[0082] (Configuration of the relay 400)

[0083] Referring to Figure 3 The configuration of the relay 400 will be described. The relay 400 is connected between the battery pack 300 and the power converter 500. The relay 400 supplies electric power from the battery pack 300 to the motor 600 via the power converter 500. In addition, the relay 400 cuts off the supply of electric power from the battery pack 300 to the motor 600 via the power converter 500.

[0084] (Configuration of the power converter 500)

[0085] Referring to Figure 3 The configuration of the power converter 500 will be described. The power converter 500 is connected between the relay 400 and the motor 600. The power converter 500 converts the power of the battery pack 300 from direct current (DC) to alternating current (AC) while performing voltage conversion. The power converter 500 includes an inverter circuit and a converter circuit.

[0086] (Configuration of the motor 600)

[0087] Referring to Figure 3 The configuration of the motor 600 is described. The motor 600 performs a power running drive to generate a driving force and a regenerative drive to recover energy, in accordance with the running state of the vehicle 1. In the power running drive of the motor 600, the electric power converter 500 converts the electric power output from the battery pack 300 from direct current to alternating current and performs voltage conversion to supply the motor 600. Thereby, the motor 600 generates a driving force, and the vehicle 1 runs. In the regenerative drive of the motor 600, the electric power converter 500 converts the electric power generated by the motor 600 from alternating current to direct current and performs voltage conversion to supply the battery pack 300. Thereby, the battery pack 300 is charged.

[0088] (Configuration of the engine 700)

[0089] Referring to Figure 3 The configuration of the engine 700 is described. The engine 700 is an internal combustion engine. The engine 700 drives the vehicle 1. The engine 700 is used as a driving source of a tire of the vehicle 1, for example. In a case where the vehicle 1 is an EV (Electric Vehicle), the engine 700 is not used.

[0090] (Effects of the embodiment)

[0091] Referring to Figures 1 to 5 The effects of the battery control device 100 and the vehicle control device 10 of the embodiment are described.

[0092] (1) The battery control device 100 has a map table and an arithmetic device 130. The map table contains data representing the relationship of the surface temperature Ts, the internal temperature Ti, and the resistance value R of the secondary battery 310. The arithmetic device 130 calculates the SOH of the secondary battery 310 from the respective amounts of change in the voltage value, the current value, and the surface temperature Ts of the secondary battery 310. The arithmetic device 130 calculates the first resistance value Rl of the secondary battery 310 from the amount of change dV in the voltage value V of the secondary battery 310 between the first time cl and the second time c2 and the amount of change dl in the current value I of the secondary battery 310 between the first time cl and the second time c2. The arithmetic device 130 calculates the amount of change β in the surface temperature Ts of the secondary battery 310 from the first surface temperature Ts 1 of the secondary battery 310 in the range from the first time cl to the second time c2 and the second surface temperature Ts2 of the secondary battery 310 at the third time c3 that is the second time c2 plus a prescribed time n. The arithmetic device 130 calculates the current amount SI of the secondary battery 310 from the time at which the first surface temperature Ts 1 of the secondary battery 310 is measured to the third time c3 at which the second surface temperature Ts2 of the secondary battery 310 is measured. The arithmetic device 130 estimates the internal temperature Ti of the secondary battery 310 from the amount of change β in the surface temperature of the secondary battery 310 and the current amount SI. The arithmetic device 130 estimates the second resistance value R2 of the secondary battery 310 that reflects the difference between the internal temperature Ti and the surface temperature Ts of the secondary battery 310, with reference to the relationship of the surface temperature Ts, the internal temperature Ti, and the resistance value R of the secondary battery 310 stored in the map table and in accordance with the estimated internal temperature Ti of the secondary battery 310. The arithmetic device 130 calculates the SOH of the secondary battery 310 from the first resistance value Rl of the secondary battery 310 and the second resistance value R2 of the secondary battery 310.

[0093] According to the battery control device 100 configured as described above, the resistance value of the secondary battery 310 is estimated in reflection of the difference between the internal temperature Ti and the surface temperature Ts of the secondary battery 310. The arithmetic device 130 calculates the SOH of the secondary battery 310 from the resistance value of the secondary battery 310. Therefore, the battery control device 100 can improve the calculation accuracy of the SOH of the secondary battery 310. That is, the battery control device 100 can improve the reliability of the secondary battery 310.

[0094] (2) The arithmetic device 130 calculates a correction value a of the surface temperature Ts of the secondary battery 310 from the amount of change β in the surface temperature Ts of the secondary battery 310 and the current amount SI. The arithmetic device 130 estimates the internal temperature Ti of the secondary battery 310 corresponding to the surface temperature Ts of the secondary battery 310 that reflects the correction value a.

[0095] According to the battery control device 100 configured as such, the internal temperature Ti of the secondary battery 310 can be estimated by a relatively general and simple method using the correction value a. Therefore, the battery control device 100 can improve the calculation accuracy of the SOH of the secondary battery 310.

[0096] (3) The calculation device 130 calculates the SOH as a rate of increase in resistance (SOHR) of the secondary battery 310, based on the first resistance value Rl and the second resistance value R2.

[0097] According to the battery control device 100 configured as such, the calculation of the SOHR, which is relatively general, can be applied based on the improvement in the calculation accuracy of the SOH of the secondary battery 310.

[0098] (4) In the data included in the mapping table, the relationship of the SOC is shown in addition to the surface temperature Ts, the internal temperature Ti, and the resistance value R of the secondary battery 310.

[0099] According to the battery control device 100 configured as such, in the case where the resistance value R of the secondary battery 310 has a correlation with the SOC, the calculation accuracy of the SOH of the secondary battery 310 can be further improved by also considering the value of the SOC of the secondary battery 310. Also, according to the battery control device 100 configured as such, in the case where the internal temperature Ti and the resistance value R of the secondary battery 310 have a correlation with the SOC, the calculation accuracy of the SOH of the secondary battery 310 can be further improved by also considering the value of the SOC of the secondary battery 310.

[0100] (5) The calculation device 130 predicts the life of the secondary battery 310 based on the SOH.

[0101] According to the battery control device 100 configured as such, by improving the calculation accuracy of the SOH of the secondary battery 310, the prediction accuracy of the life of the secondary battery 310 can be improved. Therefore, the battery control device 100 can supply power from the secondary battery 310 to an electric device such as the motor 600 before the secondary battery 310 reaches the life. That is, the battery control device 100 can use up the secondary battery 310. Also, the battery control device 100 can suppress the supply of power from the secondary battery 310 to an electric device such as the motor 600 after the secondary battery 310 reaches the life.

[0102] (6) The battery control device 100 further includes a voltage measurement unit 111 that measures the voltage value V of the secondary battery 310, a current measurement unit 112 that measures the current value I of the secondary battery 310, and a temperature measurement unit 113 that measures the surface temperature Ts of the secondary battery 310.

[0103] According to the battery control device 100 configured as such, the SOH of the secondary battery 310 can be calculated even in a case where the voltage measurement section 111, the current measurement section 112, and the temperature measurement section 113 are not provided on the secondary battery 310 side. The case where the voltage measurement section 111, the current measurement section 112, and the temperature measurement section 113 are not provided on the secondary battery 310 side includes a case where the voltage measurement section 111, the current measurement section 112, and the temperature measurement section 113 are not provided on the battery pack 300 side.

[0104] (7) The vehicle control device 10 is provided with the battery control device 100. The vehicle control device 10 controls the vehicle 1 having the secondary battery 310 and the motor 600 (electrical equipment) that operates using the electric power of the secondary battery 310.

[0105] According to the vehicle control device 10 configured as such, the motor 600 possessed by the vehicle 1 can be caused to operate more efficiently by improving the calculation accuracy of the SOH of the secondary battery 310. The electrical equipment is not limited to the motor 600. The electrical equipment may, for example, also be an air conditioner possessed by the vehicle 1.

[0106] (8) The vehicle 1 has an engine 700 (internal combustion engine) that drives the vehicle 1.

[0107] According to the vehicle control device 10 configured as such, the engine 700 can be caused to operate appropriately by improving the calculation accuracy of the SOH of the secondary battery 310. That is, the vehicle control device 10 is preferably applied to, for example, an HEV. The expression that the engine 700 is caused to operate appropriately means, for example, that the operation of the engine 700 is suppressed as much as possible in a case where it is desired to suppress the operation of the engine 700 on the basis of the operation of the vehicle 1.

[0108] (Other Embodiments)

[0109] The embodiments of the present application have been described above, but the above-described embodiments merely represent a part of application examples of the present application, and do not limit the technical scope of the present application to the specific configurations of the above-described embodiments.

[0110] For example, the battery control device 100 of the present application is not limited to a configuration that controls the secondary battery 310 used in the vehicle 1. The battery control device 100 of the present application can also be a configuration that controls the secondary battery 310 used in a working machine, an airplane, a ship, or the like.

[0111] Explanation of Symbols

[0112] 1: vehicle, 10: vehicle control device, 20: battery pack, 100: battery control device, 110: sensor unit, 111: voltage measurement unit, 112: current measurement unit, 113: temperature measurement unit, 120: map table, 121: OCV-SOC correlation table, 122: temperature correction table, 123: resistance value correlation table, 130: arithmetic device, 131: SOC estimation unit, 132: delay block, 133: internal temperature arithmetic unit, 134: first resistance arithmetic unit, 135: second resistance arithmetic unit, 136: SOHR arithmetic unit, 137: life prediction unit, 200: vehicle equipment control device, 300: battery pack, 310: secondary battery, 400: relay, 500: power converter, 600: electric motor (electrical equipment), 700: engine (internal combustion engine), Ti: internal temperature, Ts: surface temperature, Ts1: first surface temperature, Ts2: second surface temperature, c1: first time, c2: second time, c3: third time, c4: fourth time, L1: internal temperature curve, L2: surface temperature curve, L3: resistance curve before deterioration, L4: resistance curve at time of deterioration, R1: first resistance value, R2: second resistance value, SI: current amount, a: correction value, b: change amount.

Claims

1. A battery control device, characterized in that, have: A mapping table containing data representing the relationship between the surface temperature, internal temperature, and resistance value of a secondary battery; and The computing device calculates the degradation rate of the secondary battery based on the changes in its voltage, current, and surface temperature. The computing device calculates the first resistance value of the secondary battery based on the change in voltage and the change in current between the first and second time points. The computing device calculates the change in surface temperature based on a first surface temperature within the range from the first time point to the second time point and a second surface temperature at a third time point after a predetermined time has elapsed since the second time point. The computing device calculates the current of the secondary battery from the moment the first surface temperature is measured to the moment the second surface temperature is measured. Based on the change in surface temperature and the current, the internal temperature of the secondary battery is estimated. Referring to the relationship between the surface temperature, the internal temperature, and the resistance value stored in the mapping table, a second resistance value reflecting the difference between the internal temperature and the surface temperature of the secondary battery is estimated based on the estimated internal temperature. The degradation rate is calculated based on the first resistance value and the second resistance value.

2. The battery control device according to claim 1, characterized in that, The computing device calculates a correction value for the surface temperature based on the change in surface temperature and the current. The internal temperature is estimated to correspond to the surface temperature that reflects the corrected value.

3. The battery control device according to claim 1, characterized in that, The computing device calculates the degradation rate, which is the rate of increase in resistance of the secondary battery, based on the first resistance value and the second resistance value.

4. The battery control device according to claim 1, characterized in that, The data represents the relationship between the internal temperature, resistance value, and charging rate of the secondary battery.

5. The battery control device according to claim 1, characterized in that, The computing device predicts the lifespan of the secondary battery based on the degradation rate.

6. The battery control device according to claim 1, characterized in that, Further features include: A voltage measuring unit that measures the voltage value of the secondary battery; A current measuring unit that measures the current value of the secondary battery; and A temperature measuring unit measures the surface temperature of the secondary battery.

7. A vehicle control device comprising the battery control device of claim 1, characterized in that, A vehicle that controls the secondary battery and electrical equipment that operates using the power of the secondary battery.

8. The vehicle control device according to claim 7, characterized in that, The vehicle has an internal combustion engine that drives the vehicle.

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