Battery control device and vehicle control device

Abstract

A battery control device 100 includes: a calculation device (battery controller 101) that calculates the SOHR of a battery 300; and a recording device 101b that records a plurality of SOHR recorded values corresponding to at least the temperature T and SOC of the battery 300. The battery controller 101 estimates deterioration of the battery 300 on the basis of at least the SOHR. The battery controller 101 calculates the plurality of SOHR recorded values on the basis of a result of estimating the deterioration of the battery 300. The battery controller 101 records the plurality of calculated SOHR recorded values in the recording device 101b. The battery controller 101 calculates the SOHR of the battery 300 on the basis of at least the temperature T and SOC of the battery 300 and the plurality of SOHR recorded values recorded in the recording device 101b.

Description

Battery control device and vehicle control device

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

[0002] Conventionally, a technique for accurately estimating the state of a battery according to the deterioration of the battery has been known (see Patent Document 1).

[0003] Japanese Unexamined Patent Application Publication No. 2008-241246

[0004] In the control of batteries and vehicles, it is required to control the batteries and vehicles more appropriately according to the deterioration of the batteries.

[0005] The battery control device according to one aspect of the present invention includes an arithmetic device that calculates the SOHR of a secondary battery, and a recording device that records a plurality of SOHR recorded values corresponding at least to the temperature and SOC of the secondary battery. The arithmetic device estimates the deterioration of the secondary battery based at least on the SOHR. The arithmetic device calculates the plurality of SOHR recorded values based on the deterioration estimation result of the secondary battery. The arithmetic device records the calculated plurality of SOHR recorded values in the recording device. The arithmetic device calculates the SOHR of the secondary battery based at least on the temperature, the SOC, and the plurality of SOHR recorded values recorded in the recording device of the secondary battery.

[0006] The vehicle control device according to one aspect of the present invention includes the battery control device. The vehicle control device controls a vehicle having the secondary battery and an electrical device operated by the power of the secondary battery.

[0007] According to the present invention, the battery and the vehicle can be controlled more appropriately according to the deterioration of the battery.

[0008] A diagram showing the schematic configuration of a vehicle 1 equipped with the battery control device 100 of the first embodiment. A diagram showing an example of the hardware configuration of a vehicle control system mounted on vehicle 1. A functional block diagram of the battery control device 100. A functional block diagram showing the first function of the SOHR calculation unit 115 of the first embodiment. A functional block diagram showing the second function of the SOHR calculation unit 115 of the first embodiment. A functional block diagram showing the second function of the SOHR calculation unit 215 of the second embodiment. A functional block diagram showing the second function of the SOHR calculation unit 315 of the third embodiment. A functional block diagram showing the second function of the SOHR calculation unit 415 of the fourth embodiment. A functional block diagram showing the second function of the SOHR calculation unit 515 of the fifth embodiment.

[0009] Embodiments for carrying out the present invention will be described with reference to the drawings.

[0010] (First Embodiment) (Configuration of the First Embodiment) The configuration of the battery control device 100 and the vehicle control device 10 equipped with the battery control device 100 of the first embodiment will be described with reference to Figure 1.

[0011] Figure 1 is a diagram showing the schematic configuration of a vehicle 1 equipped with the battery control device 100 of the first embodiment.

[0012] As shown in Figure 1, Vehicle 1 is composed of, for example, a hybrid electric vehicle. A hybrid electric vehicle is, for example, an HEV (Hybrid Electric Vehicle) or a PHEV (Plug-in Hybrid Electric Vehicle). Hybrid electric vehicles include strong hybrid electric vehicles with an output voltage of, for example, several hundred volts, and mild hybrid electric vehicles with an output voltage of, for example, 48V. Vehicle 1 may also be composed of an EV (Electric Vehicle).

[0013] If vehicle 1 is a hybrid electric vehicle, vehicle 1 is equipped with a motor 600, which is an electrical device used to drive vehicle 1, and an engine 700, which is an internal combustion engine. The power generated by the motor 600 and the engine 700 is transmitted to the tires via a power transmission mechanism. If vehicle 1 is an EV (Electric Vehicle), vehicle 1 is not equipped with an engine 700. Therefore, the power generated by the motor 600 is transmitted to the tires via a power transmission mechanism. The motor 600 operates using electricity from the battery pack 20 and generates power.

[0014] Vehicle 1 comprises a vehicle control device 10, a battery 300, a relay 400, a power converter 500, a motor 600, and an engine 700. The vehicle control device 10 includes a battery control device 100 and a vehicle equipment control device 200. The battery pack 20 includes the battery control device 100 and a battery 300. Details of the vehicle control device 10 will be described later.

[0015] The battery 300 is composed of, for example, a battery pack. The battery pack comprises a plurality of individual cells. The plurality of individual cells are connected in series, in parallel, or in series and in parallel by busbars. The individual cells are, for example, rechargeable batteries. The rechargeable battery is, for example, a lithium-ion battery. The rechargeable battery may also be composed of a device having a power storage function, such as a nickel-metal hydride battery, a solid-state battery, a lead-acid battery, and an electric double-layer capacitor. Furthermore, the battery 300 is not limited to being composed of a plurality of rechargeable batteries, but may also be composed of a single rechargeable battery. The battery 300 is not limited to being composed of a plurality of rechargeable batteries, but may also be composed of a primary battery. The power of the battery 300 is supplied to the motor 600 via a relay 400 and a power converter 500.

[0016] Relay 400 is electrically connected to battery 300 and power converter 500. Relay 400 either supplies power from battery 300 to motor 600 or cuts off power from battery 300 to motor 600.

[0017] The power converter 500 transforms the power while converting it between direct current (DC) and alternating current (AC). The power converter 500 is electrically connected to the relay 400 and the motor 600. The power converter 500 includes an inverter circuit and a converter circuit.

[0018] The motor 600 performs both a powering operation to generate driving force and a regenerative operation to recover energy, depending on the driving state of the vehicle 1. During the powering operation of the motor 600, the power converter 500 converts the power from the battery 300 from DC to AC and transforms the voltage, supplying it to the motor 600. As a result, the motor 600 generates power, and the vehicle 1 moves. Also, if the vehicle 1 is being driven by the engine 700, the motor 600 accelerates the vehicle 1. During the regenerative operation of the motor 600, the power converter 500 converts the power generated by the motor 600 from AC to DC and transforms the voltage, supplying it to the battery 300. As a result, the battery 300 is charged.

[0019] Engine 700 is an example of an internal combustion engine. Engine 700 is used to drive vehicle 1. Engine 700 is used to power the tires of vehicle 1. If vehicle 1 is an EV (Electric Vehicle), engine 700 is not required.

[0020] The battery control device 100 and the vehicle equipment control device 200, which constitute the vehicle control device 10, are each composed of an ECU (Electronic Control Unit). Alternatively, the vehicle control device 10 may be composed of a single ECU that possesses the functions of both the battery control device 100 and the vehicle equipment control device 200. The battery control device 100 is also referred to as a Battery Management System (BMS).

[0021] The vehicle equipment control device 200 controls the drive equipment of the vehicle 1 based on battery information output by the battery control device 100. The drive equipment of the vehicle 1 includes a relay 400, a power converter 500, a motor 600, and an engine 700.

[0022] (Hardware Configuration of Vehicle Control System) Figure 2 shows an example of the hardware configuration of a vehicle control system mounted on vehicle 1. As shown in Figure 2, the battery control device 100 includes a battery controller 101, a current sensor 102 connected in series with the battery 300, a voltage sensor 103 connected in parallel with the battery 300, and a temperature sensor 104 provided on the battery 300. The current sensor 102 measures the current I of the battery 300. The voltage sensor 103 measures the voltage V of the battery 300. The temperature sensor 104 measures the temperature T (e.g., surface temperature) of the battery 300. The measurement results of the current sensor 102, the voltage sensor 103, and the temperature sensor 104 are input to the battery controller 101.

[0023] The battery controller 101 consists of a computer equipped with a processing unit 101a, a recording device 101b, an input interface, an output interface, and other peripheral circuits. These hardware components work together to operate the software and realize several functions described later (see Figure 3, etc.). The battery controller 101 may be composed of one computer or multiple computers.

[0024] The processing unit 101a includes, for example, a CPU (Central Processing Unit), an MPU (Micro Processing Unit), and a DSP (Digital Signal Processor). The recording device 101b includes non-volatile memory such as ROM (Read Only Memory), flash memory, and a hard disk drive. The recording device 101b also includes volatile memory known as RAM (Random Access Memory).

[0025] The non-volatile memory of the recording device 101b stores a program capable of performing various calculations. In other words, the non-volatile memory is a storage medium (device) from which the program realizing the functions of this embodiment can be read. The volatile memory is a storage medium (device) that temporarily stores the calculation results of the processing device 101a and signals input from the input interface. The processing device 101a is a device that expands the program stored in the non-volatile memory into the volatile memory and performs calculations, and performs predetermined calculation processing on data taken in from the input interface and the recording device 101b according to the program.

[0026] (Functions of the battery control device 100) Figure 3 is a functional block diagram of the battery control device 100. As shown in Figure 3, the battery controller 101 includes a timing unit 110, a battery information acquisition unit 111, an internal resistance calculation unit 112, an SOC calculation unit 113, an allowable current calculation unit 114, and an SOHR calculation unit 115.

[0027] The timing unit 110 measures time. The battery information acquisition unit 111 acquires battery information, which is information about the state of the battery 300, at predetermined time intervals based on the time measured by the timing unit 110. The battery information includes the measurement results of the current sensor 102, the voltage sensor 103, and the temperature sensor 104.

[0028] The internal resistance calculation unit 112 calculates the internal resistance value R of the battery 300 based on the voltage V and current I of the battery 300 acquired by the battery information acquisition unit 111. For example, when the current I changes, the internal resistance calculation unit 112 calculates the internal resistance value R (DC resistance value DCR) using the following formula (1): R = (V2 - V1) / (I2 - I1) ... (1) Here, the first current I1 is the current value before the current I changes. The first voltage V1 is the voltage value before the current I changes. The second current I2 is the current value after the current I changes. The second voltage V2 is the voltage value after the current I changes.

[0029] The SOC calculation unit 113 calculates the State of Charge (SOC) of the battery 300. The SOC calculation unit 113 calculates the SOC by, for example, integrating the current I obtained by the battery information acquisition unit 111. Alternatively, the SOC calculation unit 113 may calculate the SOC from the open-circuit voltage OCV when no charging or discharging is occurring.

[0030] The allowable current calculation unit 114 calculates the allowable current value based on the internal resistance value R calculated by the internal resistance calculation unit 112 and the state of charge (SOC) calculated by the SOC calculation unit 113. The calculation result of the allowable current calculation unit 114 is input to the vehicle equipment control device 200.

[0031] The SOHR calculation unit 115 calculates the resistance increase rate SOHR of the battery 300 based on the internal resistance value R calculated by the internal resistance calculation unit 112, the reference resistance value Ri which is the internal resistance value when the battery is new and stored in the recording device 101b, and the temperature T, state of charge (SOC), voltage V, and current I of the battery 300 acquired by the battery information acquisition unit 111. The calculation result of the SOHR calculation unit 115 is input to the vehicle equipment control device 200. The resistance increase rate SOHR is one of the indicators showing the deterioration state of the battery 300. Details of the calculation method for the resistance increase rate SOHR will be described later.

[0032] The vehicle equipment control device 200 controls various parts of the vehicle 1 based on battery information obtained from the battery control device 100. For example, the vehicle equipment control device 200 controls electrical equipment (motor 600, etc.) based on the allowable current and resistance increase rate SOHR obtained from the battery control device 100.

[0033] The resistance increase rate SOHR changes depending on the state of charge (SOC) and temperature T. Therefore, if the resistance increase rate SOHR calculated near room temperature is treated as a uniform value across all SOC and temperature ranges, errors may occur in the various controls of the battery 300 and vehicle 1 that use the resistance increase rate SOHR.

[0034] Therefore, in this embodiment, data from various degradation tests is analyzed to create a SOHR map corresponding to the charge level (SOC) and temperature T of the battery 300, and this map is fed back into various controls for the battery 300 and the vehicle 1.

[0035] (Function of SOHR calculation unit 115) Referring to Figure 4, the method for calculating the resistance increase rate SOHR using the SOHR map 150 (150d, 150c) will be explained. Figure 4 is a functional block diagram showing the first function of the SOHR calculation unit 115. As shown in Figure 4, the SOHR calculation unit 115 receives the current I and temperature T of the battery 300 from the battery information acquisition unit 111, as well as the charge rate SOC from the SOC calculation unit 113. Based on the current I, the SOHR calculation unit 115 determines whether the battery is discharging or charging. If the battery is discharging, the SOHR calculation unit 115 refers to the first SOHR map 150d and calculates the resistance increase rate SOHR based on the temperature T measured by the temperature sensor 104 and the charge rate SOC calculated by the SOC calculation unit 113. If charging is in progress, the SOHR calculation unit 115 refers to the second SOHR map 150c and calculates the resistance increase rate SOHR based on the temperature T measured by the temperature sensor 104 and the charge rate SOC calculated by the SOC calculation unit 113.

[0036] The first SOHR map 150d is a map in which multiple SOHR recorded values ​​(map values) corresponding to the temperature T and state of charge (SOC) of the battery 300 during discharge are recorded in a table format. The multiple SOHR recorded values ​​that make up the first SOHR map 150d are values ​​related to the degradation of the battery 300 due to discharge. The second SOHR map 150c is a map in which multiple SOHR recorded values ​​(map values) corresponding to the temperature T and state of charge (SOC) of the battery 300 during charging are recorded in a table format. The multiple SOHR recorded values ​​that make up the second SOHR map 150c are values ​​related to the degradation of the battery 300 due to charging. As described above, the SOHR map 150 (first SOHR map 150d and second SOHR map 150c) is created by analyzing data from various degradation tests and is pre-recorded in the recording device 101b. The multiple SOHR recorded values ​​that make up the SOHR map 150 include different values ​​corresponding to the temperature T and state of charge (SOC).

[0037] However, the characteristics of the battery 300 change due to degradation. For this reason, the SOHR calculation unit 115 estimates the degradation of the battery 300 based on at least the resistance increase rate SOHR, and generates a new SOHR map 150 according to the degradation estimation result of the battery 300. Specifically, the SOHR calculation unit 115 calculates a plurality of SOHR record values ​​based on the degradation estimation result of the battery 300, and records the calculated plurality of SOHR record values ​​in the recording device 101b. The new SOHR map 150 may be generated separately from the existing map, or it may overwrite the existing map. The SOHR calculation unit 115 calculates the resistance increase rate SOHR of the battery 300 based on at least the temperature T of the battery 300, the charge level SOC, and the newly generated SOHR map 150.

[0038] Referring to Figure 5, the calculation method for the multiple SOHR record values ​​(map values) that constitute the SOHR map in this embodiment will be explained. Figure 5 is a functional block diagram showing the second function of the SOHR calculation unit 115. The second function is the function of generating a new SOHR map 150. The second function will be explained in detail below. In the following explanation, the case in which the first SOHR map 150d is updated (i.e., overwritten) will be used as an example. As shown in Figure 5, the SOHR calculation unit 115 has a reference value calculation unit 151, a reference value comparison unit 152, a battery degradation estimation unit 153, a correction coefficient map 154, a multiplication unit 155, and SOHR maps 150A and 150B. In the figure, SOHR map 150A is the SOHR map 150 before update, and SOHR map 150B is the SOHR map 150 after update.

[0039] The reference value calculation unit 151 calculates the resistance increase rate SOHR of the battery 300 based on the internal resistance value R calculated by the internal resistance calculation unit 112 and the reference resistance value Ri stored in the recording device 101b. The internal resistance value R is calculated based on the current I measured by the current sensor 102 and the voltage V measured by the voltage sensor 103, as described above. The resistance increase rate SOHR is calculated by dividing the internal resistance value R by the reference resistance value Ri (SOHR = R / Ri).

[0040] The reference value calculation unit 151 calculates the resistance increase rate SOHR calculated when predetermined temperature conditions and predetermined SOC conditions are met, using SOHR reference value β. The predetermined temperature conditions are, for example, met when the temperature T of the battery 300 is 20°C or higher and 30°C or lower. The predetermined SOC conditions are, for example, met when the SOC of the battery 300 is 40% or higher and 60% or lower. By defining the temperature conditions and SOC conditions in this way, the error in the calculation results can be reduced. Note that the above temperature conditions and SOC conditions are just examples. For example, the temperature conditions may be set to the temperature T of the battery 300 being 15°C or higher and 25°C or lower. Also, the SOC conditions may be different for discharge and charge. The calculation accuracy of the internal resistance value R during charging is higher when the charge level SOC is lower than during discharge. For this reason, for example, the SOC condition during discharge may be set to a charge level of 50% or more and 80% or less for the battery 300, and the SOC condition during charging may be set to a charge level of 30% or more and 60% or less for the battery 300.

[0041] The reference value comparison unit 152 compares the SOHR reference value β calculated by the reference value calculation unit 151 with the map reference value βm recorded in the SOHR map 150A. The reference value comparison unit 152 uses the SOHR recorded value when the temperature T of the battery 300 is 25°C and the state of charge (SOC) of the battery 300 is 50% as the map reference value βm.

[0042] The SOHR reference value β is the current resistance increase rate SOHR, while the map reference value βm is the past resistance increase rate SOHR. The reference value comparison unit 152 determines whether the change in the resistance increase rate SOHR Δβ exceeds a predetermined change threshold Δβ0. The reference value comparison unit 152 calculates the change in the resistance increase rate SOHR Δβ by subtracting the map reference value βm from the SOHR reference value β.

[0043] The battery degradation estimation unit 153 acquires the temperature T, voltage V, and current I of the battery 300 at each time t from the battery information acquisition unit 111 (hereinafter referred to as the time history data of the battery 300). The time history data of the battery 300 is data (load information, operation information) representing the usage history of the battery 300. The battery degradation estimation unit 153 estimates the polarization resistance characteristics 153b of the battery 300 based on the internal battery degradation model 153a and the time history data of the battery 300. The polarization resistance characteristics 153b include the polarization resistance characteristics of the positive electrode and the polarization resistance characteristics of the negative electrode.

[0044] The internal battery degradation model 153a includes a first function f(t, T, V, I), a second function g(t, T, V, I), and a third function h(t, T, V, I). The first function f(t, T, V, I) is a function for estimating the degree of degradation of the positive electrode of the battery 300 based on the time history data of the battery 300. The second function g(t, T, V, I) is a function for estimating the degree of degradation of the negative electrode of the battery 300 based on the time history data of the battery 300. The third function h(t, T, V, I) is a function for estimating the error in the battery capacity due to side reactions of the battery 300 based on the time history data of the battery 300. These functions f(t, T, V, I), g(t, T, V, I), h(t, T, V, I) are derived from empirical rules.

[0045] The battery degradation estimation unit 153 estimates the resistance characteristics of the battery 300 based on the polarization resistance characteristics 153b of the battery 300, and generates a correction coefficient map 154 based on the estimation result. The correction coefficient map 154 is a map in which a plurality of correction coefficients α corresponding to the temperature T and the state of charge SOC of the battery 300 are recorded in a table format. When the battery degradation estimation unit 153 determines that the change amount Δβ of the resistance increase rate SOHR exceeds the change amount threshold value Δβ0 by the reference value comparison unit 152, the battery degradation estimation unit 153 estimates the degradation of the battery 300 using the internal battery degradation model 153a, and updates the correction coefficient map 154 based on the degradation estimation result of the battery 300. Thus, in the present embodiment, the battery degradation estimation unit 153 calculates a plurality of correction coefficients α based on the usage history including the degree of degradation of the positive electrode, the degree of degradation of the negative electrode, and the error in the battery capacity of the battery 300.

[0046] When the correction coefficient map 154 is updated by the battery degradation estimation unit 153, the multiplication unit 155 updates the SOHR map 150. Specifically, the multiplication unit 155 multiplies each of the plurality of correction coefficients α that make up the correction coefficient map 154 by the SOHR reference value β calculated by the reference value calculation unit 151. As a result, a plurality of new SOHR recorded values are calculated. The calculated SOHR recorded values overwrite the existing SOHR recorded values. Thereby, the updated SOHR map 150B is generated.

[0047] In addition, when the result of multiplying the correction coefficient α and the SOHR reference value β is less than 100%, the multiplication unit 155 sets the SOHR recorded value to 100%. That is, the lower limit value of the SOHR recorded values that make up the SOHR map 150 is set to 100%. Thereby, it is possible to prevent a control failure due to the SOHR recorded value being less than 100%.

[0048] (Effect of the First Embodiment) According to this first embodiment, the following operational effects are achieved.

[0049] As shown in Figure 3, the battery control device 100 has a battery controller 101 as a calculation device for calculating the resistance increase rate SOHR of the battery (secondary battery) 300. The battery control device 100 has a recording device 101b that records a plurality of SOHR record values ​​(see Figure 4) corresponding to at least the temperature T and state of charge (SOC) of the battery 300. As shown in Figure 5, the battery controller 101 estimates the degradation of the battery 300 based at least on the resistance increase rate SOHR. The battery controller 101 calculates a plurality of SOHR record values ​​based on the degradation estimation result of the battery 300. The battery controller 101 records the calculated plurality of SOHR record values ​​in the recording device 101b. As shown in Figure 4, the battery controller 101 calculates the resistance increase rate SOHR of the battery 300 based at least on the temperature T, state of charge (SOC) of the battery 300, and the plurality of SOHR record values ​​recorded in the recording device 101b. With this configuration, the degradation estimation result of the battery 300 can be reflected in the control of the battery 300. In other words, the battery 300 and the vehicle 1 can be appropriately controlled in accordance with the degradation of the battery 300. As a result, the battery 300 can perform at its maximum capacity until, for example, the end of its lifespan (EOL).

[0050] As shown in Figure 5, the battery controller 101 calculates a plurality of correction coefficients α corresponding to at least the temperature T and state of charge (SOC) of the battery 300, based on the degradation estimation result of the battery 300. The battery controller 101 calculates a plurality of SOHR record values ​​based on the calculated plurality of correction coefficients α and a predetermined SOHR reference value β. The battery controller 101 records the calculated plurality of SOHR record values ​​in the recording device 101b. With this configuration, an appropriate SOHR map 150 can be generated based on the predetermined SOHR reference value β.

[0051] The battery controller 101 calculates multiple correction coefficients α based on the usage history of the battery 300. This means that if the battery 300 is used infrequently, a corresponding correction coefficient α is calculated. Similarly, if the battery 300 is used frequently, a corresponding correction coefficient α is calculated.

[0052] The usage history includes the degree of degradation of the positive electrode, the degree of degradation of the negative electrode, and the error in the battery capacity of the battery 300. With this configuration, the degradation of the battery 300 can be estimated with greater accuracy compared to when this information is not considered. As a result, an appropriate correction coefficient α can be obtained according to the degradation state of the battery 300.

[0053] The SOHR recorded values ​​that make up the first SOHR map 150d are values ​​related to the degradation of the battery 300 due to charging. The SOHR recorded values ​​that make up the second SOHR map 150c are values ​​related to the degradation of the battery 300 due to discharging. With this configuration, an appropriate resistance increase rate SOHR can be calculated according to the charge and discharge state of the battery 300.

[0054] The battery control device 100 includes a current sensor 102 for measuring the current I of the battery 300, a voltage sensor 103 for measuring the voltage V of the battery 300, and a temperature sensor 104 for measuring the temperature T of the battery 300. The battery controller 101 calculates the resistance increase rate SOHR of the battery 300 based on one or more of the current I measured by the current sensor 102, the voltage V measured by the voltage sensor 103, and the temperature T measured by the temperature sensor 104. With this configuration, a highly reliable resistance increase rate SOHR can be obtained based on the measurement results of the sensors.

[0055] The battery controller 101 calculates the state of charge (SOC) of the battery 300 based on one or more of the current I measured by the current sensor 102 and the voltage V measured by the voltage sensor 103. The battery controller 101 calculates the resistance increase rate (SOHR) based on the calculated SOC, the temperature T measured by the temperature sensor 104, and a plurality of SOHR recording values. With this configuration, an appropriate resistance increase rate (SOHR) corresponding to the SOC and temperature T can be obtained using the plurality of SOHR recording values.

[0056] The battery controller 101 calculates the resistance increase rate SOHR of the battery 300 based on at least the current I measured by the current sensor 102 and the voltage V measured by the voltage sensor 103. The battery controller 101 uses the calculated resistance increase rate SOHR when predetermined temperature conditions and predetermined SOC conditions are met as the SOHR reference value β. With this configuration, a highly accurate resistance increase rate SOHR can be used as the SOHR reference value β. As a result, a highly accurate SOHR map 150 can be generated.

[0057] The battery controller 101 calculates multiple SOHR record values ​​based on multiple correction coefficients α and the SOHR reference value β when the change amount Δβ of the SOHR reference value exceeds a predetermined change amount threshold Δβ0. The battery controller 101 records the calculated multiple SOHR record values ​​in the recording device 101b. With this configuration, if the change amount Δβ of the SOHR reference value does not exceed the predetermined change amount threshold Δβ0, no new SOHR record values ​​are calculated. This reduces the computational load on the battery controller 101.

[0058] The vehicle control device 10 includes a battery control device 100 having the above-described features. The vehicle control device 10 controls a vehicle 1 having a battery 300 and electrical equipment (motor 600, etc.) that operates using the power of the battery 300. With this configuration, the reliability of the resistance increase rate SOHR used in the calculations of the vehicle control device 10 is improved, so that the vehicle control device 10 can control the electrical equipment (motor 600, etc.) more appropriately.

[0059] As shown in Figure 1, the vehicle 1 has an internal combustion engine (engine 700) that drives the vehicle 1. Because the reliability of the resistance increase rate SOHR used in various calculations in the vehicle control device 10 is improved, the vehicle control device 10 can more appropriately control the motor 600 and engine 700 when the vehicle is running.

[0060] (Second Embodiment) (Functions of the SOHR Calculation Unit 215 in the Second Embodiment) The second function of the SOHR calculation unit 215 of the battery control device in the second embodiment will be described with reference to Figure 6. Note that the first function of the SOHR calculation unit 215 is the same as the first function of the SOHR calculation unit 115, so its description will be omitted. Figure 6 is a functional block diagram showing the second function of the SOHR calculation unit 215 in the second embodiment. For the SOHR calculation unit 215, the same reference numerals are used for components with the same configuration as the SOHR calculation unit 115, and their description is omitted. For the SOHR calculation unit 215, different reference numerals are used for components with a different configuration than the SOHR calculation unit 115.

[0061] In the first embodiment, an example was described in which the SOHR calculation unit 115 estimates the degradation of the battery 300 based on the battery internal degradation model 153a and generates an SOHR map 150 based on the estimation result. In contrast, the SOHR calculation unit 215 of this second embodiment generates the SOHR map 150 without using the battery internal degradation model 153a. In other words, in this second embodiment, the correction coefficient map 154 ​​is not updated by the battery degradation estimation unit 153. The correction coefficient map 154 ​​is an initial map that has been previously recorded in the recording device 101b.

[0062] In the second embodiment, the multiplication unit 155 updates the SOHR map 150 when the reference value comparison unit 152 determines that the change amount Δβ of the resistance increase rate SOHR exceeds the change amount threshold Δβ0. Specifically, the multiplication unit 155 multiplies each of the multiple correction coefficients α constituting the correction coefficient map 154 ​​by the SOHR reference value β calculated by the reference value calculation unit 151. This calculates multiple new SOHR record values. The calculated SOHR record values ​​overwrite the existing SOHR record values. This generates the updated SOHR map 150B.

[0063] (Effects of the Second Embodiment) The battery controller 101 of the second embodiment calculates the resistance increase rate SOHR of the battery 300 based on the current I measured by the current sensor 102 and the voltage V measured by the voltage sensor 103. The battery controller 101 sets the calculated resistance increase rate SOHR when predetermined temperature conditions and predetermined SOC conditions are met as the SOHR reference value β. When the change amount Δβ of the SOHR reference value exceeds a predetermined change amount threshold Δβ0, the battery controller 101 calculates a plurality of SOHR record values ​​based on a plurality of correction coefficients α and the SOHR reference value β. The battery controller 101 records the calculated plurality of SOHR record values ​​in the recording device 101b. With this configuration, the change in the resistance increase rate SOHR obtained as a result of the degradation estimation of the battery 300 can be reflected in the control of the battery 300. As a result, the battery 300 can perform at its maximum capacity until, for example, the end of its life (EOL). Furthermore, with this configuration, if the change amount Δβ of the SOHR reference value does not exceed a predetermined change amount threshold Δβ0, a new SOHR record value is not calculated. This reduces the computational load on the battery controller 101.

[0064] In this second embodiment, the correction coefficient map may be input to the battery controller 101 via an input device, a communication device, and a storage medium, and recorded in the recording device 101b.

[0065] (Third Embodiment) (Functions of the SOHR Calculation Unit 315 in the Third Embodiment) The second function of the SOHR calculation unit 315 of the battery control device in the third embodiment will be described with reference to Figure 7. Note that the first function of the SOHR calculation unit 315 is the same as the first function of the SOHR calculation unit 115, so its description will be omitted. Figure 7 is a functional block diagram showing the second function of the SOHR calculation unit 315 in the third embodiment. For the SOHR calculation unit 315, components with the same configuration as the SOHR calculation unit 115 are given the same reference numerals as the SOHR calculation unit 115 and their descriptions are omitted. For the SOHR calculation unit 315, components with a different configuration from the SOHR calculation unit 115 are given different reference numerals. Note that although not shown, the SOHR calculation unit 315 includes a reference value comparison unit 152 and a battery degradation estimation unit 153.

[0066] The SOHR calculation unit 315 of the third embodiment includes a reference value calculation unit 151, a reference value comparison unit 152 (not shown), a battery degradation estimation unit 153 (not shown), a correction coefficient map 154, a multiplication unit 155, and an SOHR map 150. The SOHR calculation unit 315 further includes a reference resistance value calculation unit 356, a multiplication unit 357, and a DCR map 358.

[0067] The DCR map 358 is a map in which multiple DCR recording values ​​(map values) corresponding to the temperature T and state of charge (SOC) of the battery 300 are recorded in a table format.

[0068] The reference resistance calculation unit 356 calculates the reference resistance value Ri based on the state of charge (SOC) of the battery 300 calculated by the SOC calculation unit 113, the temperature T of the battery 300 measured by the temperature sensor 104, and the temperature-resistance correlation map. The temperature-resistance correlation map is a data table that defines the correlation between the temperature T of the battery 300 and the reference resistance value Ri. The temperature-resistance correlation map is predetermined through experiments, etc., and recorded in the recording device 101b. The recording device 101b stores multiple temperature-resistance correlation maps corresponding to the state of charge (SOC).

[0069] When a new SOHR map 150 is generated, the multiplication unit 357 multiplies each of the multiple SOHR record values ​​constituting the new SOHR map 150 by the reference resistance value Ri calculated by the reference resistance value calculation unit 356. This calculates multiple new DCR record values. The calculated multiple DCR record values ​​overwrite the existing DCR record values. This generates the updated DCR map 358.

[0070] In other words, the multiplication unit 357 updates the DCR map 358 when the SOHR map 150 is updated. Note that the DCR map 358 is not limited to overwriting an existing map. The new DCR map 358 may be generated separately from the existing map.

[0071] Although not shown in the figures, the internal resistance calculation unit 112 according to this third embodiment refers to the DCR map 358 and calculates the internal resistance value R (DC resistance value DCR) based on the temperature T measured by the temperature sensor 104 and the state of charge (SOC) calculated by the SOC calculation unit 113. The internal resistance value R calculated in this way is used for calculating and controlling various parameters of the battery 300 (such as the state of charge (SOC) and the resistance increase rate (SOHR)).

[0072] (Effects of the Third Embodiment) The recording device 101b of the battery controller 101 in the third embodiment stores a plurality of DCR recording values ​​corresponding to at least the temperature T and state of charge (SOC) of the battery 300. The battery controller 101 calculates a plurality of DCR recording values ​​based on the plurality of SOHR recording values ​​recorded in the recording device 101b. The battery controller 101 records the calculated plurality of DCR recording values ​​in the recording device 101b. The battery controller 101 calculates the internal resistance value R (DC resistance value DCR) of the battery 300 based on at least the temperature T, state of charge (SOC) of the battery 300, and the plurality of DCR recording values ​​recorded in the recording device 101b. With this configuration, in addition to the same effects as in the first embodiment, a highly reliable internal resistance value R (DC resistance value DCR) corresponding to the temperature T and state of charge (SOC) can be obtained. The internal resistance value R is used for various controls of the battery 300 and the vehicle 1.

[0073] (Fourth Embodiment) (Functions of the SOHR Calculation Unit 415 in the Fourth Embodiment) The second function of the SOHR calculation unit 415 of the battery control device in the fourth embodiment will be described with reference to Figure 8. Note that the first function of the SOHR calculation unit 415 is the same as the first function of the SOHR calculation unit 115, so its description will be omitted. Figure 8 is a functional block diagram showing the second function of the SOHR calculation unit 415 in the fourth embodiment. For the SOHR calculation unit 415, the same reference numerals are used as for the SOHR calculation units 115 and 315, and the description will be omitted. For the SOHR calculation unit 415, different reference numerals are used as for the SOHR calculation units 115 and 315, and the description will be omitted. For the SOHR calculation unit 415, different reference numerals are used as for the SOHR calculation units 115 and 315, and the description will be omitted. Note that although not shown, the SOHR calculation unit 415 has a reference value comparison unit 152 and a battery degradation estimation unit 153.

[0074] The SOHR calculation unit 415 of the fourth embodiment includes a reference value comparison unit 152 (not shown), a battery degradation estimation unit 153 (not shown), a correction coefficient map 154, an SOHR map 150, a reference resistance value calculation unit 356, and a DCR map 358. The SOHR calculation unit 415 of the fourth embodiment has a reference value calculation unit 451 and a multiplication unit 455 instead of the reference value calculation unit 151 and multiplication unit 155 of the third embodiment. Also, the SOHR calculation unit 415 of the fourth embodiment has a division unit 457 instead of the multiplication unit 357 of the third embodiment.

[0075] The reference value calculation unit 451 has the following functions in addition to the functions of the reference value calculation unit 151. The reference value calculation unit 451 calculates the internal resistance value R calculated when predetermined temperature conditions and predetermined SOC conditions are met as the resistance reference value β1. The predetermined temperature conditions are met, for example, when the temperature T of the battery 300 is 20°C or higher and 30°C or lower. The predetermined SOC conditions are met, for example, when the charge level SOC of the battery 300 is 40% or higher and 60% or lower.

[0076] The multiplication unit 455 updates the DCR map 358 when the correction coefficient map 154 ​​is updated. Specifically, the multiplication unit 455 multiplies each of the multiple correction coefficients α that make up the correction coefficient map 154 ​​by the resistance reference value β1 calculated by the reference value calculation unit 451. This calculates multiple new DCR record values. The calculated DCR record values ​​overwrite the existing DCR record values. This generates the updated DCR map 358.

[0077] The division unit 457 updates the SOHR map 150 when the DCR map 358 is updated. Specifically, the division unit 457 divides each of the multiple DCR record values ​​constituting the DCR map 358 by the reference resistance value Ri calculated by the reference resistance value calculation unit 356. This calculates multiple new SOHR record values. The calculated multiple SOHR record values ​​overwrite the existing SOHR record values. This generates the updated SOHR map 150.

[0078] Furthermore, the DCR map 358 and SOHR map 150 are not limited to overwriting existing maps. The new DCR map 358 and SOHR map 150 may be generated separately from the existing maps.

[0079] (Effects of the Fourth Embodiment) The recording device 101b of the battery controller 101 of the fourth embodiment records a plurality of DCR recording values ​​corresponding to at least the temperature T and state of charge (SOC) of the battery 300. The battery controller 101 calculates a plurality of correction coefficients α corresponding to at least the temperature T and state of charge (SOC) of the battery 300 based on the degradation estimation result of the battery 300. The battery controller 101 calculates a plurality of DCR recording values ​​based on the plurality of correction coefficients α and a predetermined DCR reference value. The battery controller 101 records the calculated plurality of DCR recording values ​​in the recording device 101b. The battery controller 101 calculates a plurality of SOHR recording values ​​based on the plurality of DCR recording values ​​recorded in the recording device 101b. With this configuration, the same effects as the third embodiment can be obtained.

[0080] (Fifth Embodiment) (Functions of the SOHR Calculation Unit 515 in the Fifth Embodiment) The second function of the SOHR calculation unit 515 of the battery control device in the fifth embodiment will be described with reference to Figure 9. Note that the first function of the SOHR calculation unit 515 is the same as the first function of the SOHR calculation unit 115, so its description will be omitted. Figure 9 is a functional block diagram showing the second function of the SOHR calculation unit 515 in the fifth embodiment. For the SOHR calculation unit 515, the same reference numerals are used for components with the same configuration as the SOHR calculation unit 115, and their description is omitted. For the SOHR calculation unit 515, different reference numerals are used for components with a different configuration than the SOHR calculation unit 115.

[0081] In the first embodiment, an example was described in which the SOHR calculation unit 115 generates an SOHR map 150 using a correction coefficient map 154 ​​(see Figure 5) consisting of multiple correction coefficients α. In contrast, the SOHR calculation unit 515 of this fifth embodiment calculates a single correction coefficient α based on the change in the resistance increase rate SOHR, which represents the degradation estimation result of the battery 300, and generates an SOHR map 150 using the calculation result.

[0082] The SOHR calculation unit 515 of the fifth embodiment includes a reference value calculation unit 151, a reference value comparison unit 152, a multiplication unit 555, a correction coefficient calculation unit 559, and SOHR maps 150A and 150B.

[0083] The correction coefficient calculation unit 559 calculates a single correction coefficient α1 by dividing the SOHR reference value β by the map reference value βm when the reference value comparison unit 152 determines that the change amount Δβ of the resistance increase rate SOHR exceeds the change amount threshold Δβ0. The correction coefficient α1 is the ratio of the map reference value βm to the SOHR reference value β, and can be said to be a parameter that represents the degradation estimation result of the battery 300. For example, if the SOHR reference value β is 130% and the map reference value βm is 125%, the correction coefficient α1 will be 1.04. The multiplication unit 555 multiplies each of the multiple SOHR record values ​​that constitute the SOHR map 150A by the correction coefficient α1 calculated by the correction coefficient calculation unit 559. As a result, multiple new SOHR record values ​​are calculated. The calculated SOHR record values ​​overwrite the existing SOHR record values. As a result, the updated SOHR map 150B is generated.

[0084] Thus, in this fifth embodiment, the resistance increase rate SOHR is measured, and compared with the map values ​​at the temperature T and state of charge SOC at that time. If the difference is large, all SOHR record values ​​constituting the SOHR map 150 are updated. Note that the SOHR map 150 is not limited to overwriting an existing map. The new SOHR map 150 may be generated separately from the existing map.

[0085] (Effects of the Fifth Embodiment) The battery controller 101 calculates the ratio of a predetermined SOHR record value (map reference value βm) included in a plurality of SOHR record values ​​to the calculated resistance increase rate SOHR (SOHR reference value β) as the degradation estimation result of the battery 300. The battery controller 101 calculates a new plurality of SOHR record values ​​based on the calculated ratio (correction coefficient α1) and the plurality of SOHR record values. The battery controller 101 records the newly calculated plurality of SOHR record values ​​in the recording device 101b. The battery controller 101 calculates the resistance increase rate SOHR of the battery 300 based on at least the temperature T of the battery 300, the charge level SOC, and the new plurality of SOHR record values ​​recorded in the recording device 101b. With this configuration, when the resistance increase rate SOHR, which is an indicator of the degradation state of the battery 300, changes, a new plurality of SOHR record values ​​can be recorded in accordance with the change. As a result, appropriate control can be performed according to the degradation state of the battery 300.

[0086] The following modifications are also within the scope of the present invention, and it is possible to combine the configurations shown in the modifications with the configurations described in the embodiments described above, or to combine the configurations described in the following different modifications.

[0087] (Modification 1) An example has been described in which the internal battery degradation model 153a includes a first function f(t, T, V, I) for estimating the degree of degradation of the positive electrode of the battery 300, a second function g(t, T, V, I) for estimating the degree of degradation of the negative electrode of the battery 300, and a third function h(t, T, V, I) for estimating the error in battery capacity. However, the present invention is not limited thereto. Preferably, the internal battery degradation model 153a includes at least one of the functions f(t, T, V, I), g(t, T, V, I), and h(t, T, V, I). By using one or more of the functions f(t, T, V, I), g(t, T, V, I), and h(t, T, V, I) and the time history data of the battery 300, a degradation estimation result for the battery 300 can be obtained that takes into account the usage history, including one or more of the degree of degradation of the positive electrode, the degree of degradation of the negative electrode, and the error in battery capacity.

[0088] (Modification 2) The battery controller 101 may calculate the SOHR reference value β based on the usage history of the battery 300. In this case, it is preferable that the usage history includes one or more of the following: the degree of degradation of the positive electrode of the battery 300, the degree of degradation of the negative electrode, and the error in the battery capacity. For example, in the first embodiment shown in Figure 5, the battery degradation estimation unit 153 may correct (change) the SOHR reference value β based on the time history data of the battery 300 and the degradation estimation result of the battery 300 using the battery internal degradation model 153a. In this case, the multiplication unit 155 multiplies each of the multiple correction coefficients α constituting the correction coefficient map 154 ​​by the corrected SOHR reference value β. As a result, multiple new SOHR recorded values ​​are calculated. With such a configuration, the accuracy of multiple SOHR recorded values ​​can be further improved. In addition, in the second to fourth embodiments, the battery controller 101 may correct (change) the SOHR reference value β based on the usage history of the battery 300.

[0089] (Modification 3) In the above embodiment, an example was described in which the SOHR map 150 recorded in the recording device 101b includes a first SOHR map 150d used when charging and a second SOHR map 150c used when discharging. However, the present invention is not limited thereto. Only one of the first SOHR map 150d and the second SOHR map 150c may be recorded in the recording device 101b. That is, the SOHR recorded values ​​constituting the SOHR map 150 may be values ​​relating to one or more of the degradation values ​​associated with charging of the battery 300 and the degradation values ​​associated with discharging of the battery 300.

[0090] Although embodiments of the present invention have been described above, these embodiments only represent a part of the application examples of the present invention, and the technical scope of the present invention is not intended to be limited to the specific configurations of the above embodiments. For example, the present invention is not limited to applications to a battery control device 100 that controls a battery 300 mounted on a vehicle 1 as shown in Figure 1. The present invention can be applied to a battery control device 100 that controls a battery 300 used as a power source for operating various industrial machines such as aircraft and machine tools.

[0091] 1...Vehicle, 10...Vehicle control device, 20...Battery pack, 100...Battery control device, 101...Battery controller (calculation unit), 101a...Processing device, 101b...Recording device, 102...Current sensor, 103...Voltage sensor, 104...Temperature sensor, 110...Timekeeping unit, 111...Battery information acquisition unit, 112...Internal resistance calculation unit, 113...SOC calculation unit, 114...Allowable current calculation unit, 115...SOHR calculation unit, 150...SOHR Map, 150A...SOHR map (before update), 150B...SOHR map (after update), 150c...Second SOHR map, 150d...First SOHR map, 151...Reference value calculation unit, 152...Reference value comparison unit, 153...Battery degradation estimation unit, 153a...Battery internal degradation model, 153b...Polarization resistance characteristics, 154...Correction coefficient map, 155...Multiplication unit, 200...Vehicle equipment control device, 215...SOHR calculation unit, 300...Battery (Secondary battery), 315...SOHR calculation unit, 356...Reference resistance value calculation unit, 357...Multiplication unit, 358...DCR map, 400...Relay, 415...SOHR calculation unit, 451...Reference value calculation unit, 455...Multiplication unit, 457...Division unit, 500...Power converter, 515...SOHR calculation unit, 555...Multiplication unit, 559...Correction coefficient calculation unit, 600...Motor (electrical equipment), 700...Engine (internal combustion engine), DCR...DC resistance value, f... g...First function, h...Second function, I...Current, I1...First current, I2...Second current, OCV...Open circuit voltage, R...Internal resistance, Ri...Reference resistance, SOC...Charging level, SOHR...Resistance increase rate, t...Time, T...Temperature, V...Voltage, V1...First voltage, V2...Second voltage, α...Correction coefficient, α1...Correction coefficient, β...SOHR reference value, β1...Resistance reference value, βm...Map reference value, Δβ...Change in resistance increase rate, Δβ0...Change threshold

Claims

1. A battery control device comprising: a calculation device for calculating the SOHR of a secondary battery; and a recording device for recording a plurality of SOHR record values ​​corresponding to at least the temperature and SOC of the secondary battery; wherein the calculation device estimates the degradation of the secondary battery based at least on the SOHR; calculates the plurality of SOHR record values ​​based on the degradation estimation result of the secondary battery; records the calculated plurality of SOHR record values ​​in the recording device; and calculates the SOHR of the secondary battery based at least on the temperature of the secondary battery, the SOC, and the plurality of SOHR record values ​​recorded in the recording device.

2. The battery control device according to claim 1, wherein the calculation device calculates a plurality of correction coefficients corresponding to at least the temperature and SOC of the secondary battery based on the degradation estimation result of the secondary battery, calculates a plurality of SOHR record values ​​based on the calculated plurality of correction coefficients and a predetermined SOHR reference value, and records the calculated plurality of SOHR record values ​​in the recording device.

3. The battery control device according to claim 2, wherein the calculation device calculates the plurality of correction coefficients based on the usage history of the secondary battery.

4. The battery control device according to claim 3, wherein the usage history includes one or more of the degree of deterioration of the positive electrode, the degree of deterioration of the negative electrode, and the error in the battery capacity of the secondary battery.

5. The battery control device according to claim 2, wherein the calculation device calculates the SOHR reference value based on the usage history of the secondary battery.

6. The battery control device according to claim 5, wherein the usage history includes one or more of the degree of deterioration of the positive electrode, the degree of deterioration of the negative electrode, and the error in the battery capacity of the secondary battery.

7. The battery control device according to claim 1, wherein the recording device records a plurality of DCR recording values ​​corresponding to at least the temperature and SOC of the secondary battery, the calculation device calculates the plurality of DCR recording values ​​based on the plurality of SOHR recording values ​​recorded in the recording device, records the calculated plurality of DCR recording values ​​in the recording device, and calculates the DCR of the secondary battery based on at least the temperature, SOC of the secondary battery, and the plurality of DCR recording values ​​recorded in the recording device.

8. The battery control device according to claim 1, wherein the recording device records a plurality of DCR recording values ​​corresponding to at least the temperature and SOC of the secondary battery; the calculation device calculates a plurality of correction coefficients corresponding to at least the temperature and SOC of the secondary battery based on the degradation estimation result of the secondary battery; calculates a plurality of DCR recording values ​​based on the plurality of correction coefficients and a predetermined DCR reference value; records the calculated plurality of DCR recording values ​​in the recording device; and calculates a plurality of SOHR recording values ​​based at least the temperature of the secondary battery, the SOC, and the plurality of DCR recording values ​​recorded in the recording device.

9. The battery control device according to claim 1, wherein the calculation device calculates the ratio of a predetermined SOHR record value included in the plurality of SOHR record values ​​to the calculated SOHR as a degradation estimation result of the secondary battery; calculates a new plurality of SOHR record values ​​based on the calculated ratio and the plurality of SOHR record values; records the calculated new plurality of SOHR record values ​​in the recording device; and calculates the SOHR of the secondary battery based on the new plurality of SOHR record values ​​recorded in the recording device.

10. The battery control device according to claim 1, wherein the SOHR recorded value is a value relating to one or more of the degradation values ​​associated with charging the secondary battery and the degradation values ​​associated with discharging the secondary battery.

11. The battery control device according to claim 1, further comprising: a current sensor for measuring the current of the secondary battery; a voltage sensor for measuring the voltage of the secondary battery; and a temperature sensor for measuring the temperature of the secondary battery, wherein the calculation device calculates the SOHR of the secondary battery based on one or more of the current measured by the current sensor, the voltage measured by the voltage sensor, and the temperature measured by the temperature sensor.

12. The battery control device according to claim 2, wherein the calculation device calculates the SOHR of the secondary battery based on at least the current measured by a current sensor and the voltage measured by a voltage sensor, and sets the SOHR calculated when predetermined temperature conditions and predetermined SOC conditions are met as the SOHR reference value.

13. The battery control device according to claim 12, wherein the calculation device calculates the plurality of SOHR record values ​​based on the plurality of correction coefficients and the SOHR reference value when the amount of change of the SOHR reference value exceeds a predetermined change threshold, and records the calculated plurality of SOHR record values ​​in the recording device.

14. A vehicle control device comprising the battery control device described in claim 1, which controls a vehicle having a secondary battery and electrical equipment that operates using the power of the secondary battery.

15. The vehicle control device according to claim 14, wherein the vehicle has an internal combustion engine that drives the vehicle.

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