Recharge control device for secondary batteries

Abstract

The present invention provides a secondary battery charging control device that can efficiently warm up and charge the entire battery pack, which is composed of multiple secondary batteries, according to the charging settings. [Solution] The charging control device 40 comprises a battery temperature sensor 11, a battery temperature control device 20, a DC-DC converter 4, a BECM 10, and a PCM 14. The battery temperature sensor 11 and the DC-DC converter 4 are provided for each of the multiple battery modules. The BECM 10 and the PCM 14 determine the warm-up order of the multiple battery modules to maximize the charging demands of the multiple battery modules under predetermined setting conditions, if there are previous battery modules with a temperature lower than the first temperature T1. Furthermore, they control the DC-DC converter 4 to simultaneously charge the multiple battery modules with a maximum current value set based on their respective temperatures.

Description

[Technical Field]

[0001] This disclosure relates to a charging control device for a secondary battery. [Background technology]

[0002] Conventionally, electric vehicles are known, which are vehicles that are equipped with multiple secondary batteries (hereinafter sometimes simply referred to as batteries) as a power source and run on electricity supplied from these batteries. In addition, various technologies have been proposed for charging multiple secondary batteries in a short time (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses a configuration for charging multiple secondary batteries by staggering the heating timing and charging timing of the batteries according to the temperature of the batteries to be charged. This method can shorten the total charging time. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-101151 [Overview of the project] [Problems that the invention aims to solve]

[0005] Incidentally, when considering the convenience of electric vehicles, it is necessary to be able to charge more in a set amount of time, or to charge a set amount in a shorter amount of time. To achieve this, increasing the charging current is effective, but when the battery temperature is low, the charging current cannot be increased due to safety concerns. For this reason, especially when charging from an empty state in winter when the battery temperature is low, not much charge is achieved in a short time, and it may take several hours, including the time required to warm up the battery, to reach a high charge level, which greatly impairs the convenience of electric vehicles.

[0006] To address these problems, Patent Document 1 describes a method for efficiently warming up multiple secondary batteries and shortening charging time by sequentially warming up and charging multiple secondary batteries that constitute a battery pack (battery assembly), and transferring the heat from the secondary battery that has finished charging first to the other secondary batteries that have not been warmed up and charged sufficiently. On the other hand, when there are multiple secondary batteries with different temperatures, the time progression of the charge amount changes depending on the warming order of these secondary batteries, but this point is not mentioned.

[0007] This disclosure has been made in view of the foregoing, and its purpose is to provide a secondary battery charging control device that can efficiently warm up and charge the entire battery pack, which is composed of multiple secondary batteries, according to the charging settings and the temperature of each battery. [Means for solving the problem]

[0008] To achieve the above objective, the secondary battery charge control device according to the present disclosure is a charge control device for secondary batteries constituting a battery pack, wherein a plurality of secondary batteries included in the battery pack are connected in parallel during operation, and the charge control device comprises: a battery temperature detection means provided for each of the plurality of secondary batteries for detecting the temperature of the secondary battery; a battery temperature adjustment device capable of switching which secondary battery to be warmed up; a charge current adjustment device provided for each of the plurality of secondary batteries capable of adjusting the charge current to decrease as the temperature of the secondary battery decreases; and a control device that controls the battery temperature adjustment device and the charge current adjustment device, respectively, wherein, when there are a plurality of secondary batteries among the plurality of secondary batteries whose temperature is lower than a first temperature which is the warm-up completion temperature, the control device determines the order in which to warm up the plurality of secondary batteries in order to maximize the demand for charging as a battery pack under predetermined setting conditions, and controls the charge current adjustment device to perform charging simultaneously and at the same time as the start of the first warm-up with a maximum current value set based on each temperature. [Effects of the Invention]

[0009] According to this disclosure, when charging a battery pack composed of multiple secondary batteries, it becomes possible to efficiently charge the entire battery pack by performing warm-up control based on the temperature state of each battery. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic diagram of the main part of the high-voltage circuit of the vehicle according to Embodiment 1. [Figure 2] This is a functional block diagram showing the configuration of the vehicle's charging control device. [Figure 3] This is a schematic diagram of a battery module including a battery temperature control device. [Figure 4] This is a schematic diagram showing the relationship between SOC and charging current in a battery module. [Figure 5] This flowchart shows the first battery charging control procedure and warm-up control procedure. [Figure 6A] This is a flowchart of subprocess A. [Figure 6B] This is a flowchart of subprocess B. [Figure 6C] This is a flowchart of subprocess C. [Figure 6D] This is a flowchart of subprocess D. [Figure 6E] This is a flowchart of subprocess E. [Figure 6F] This is a flowchart of subprocess F. [Figure 7] This is a flowchart showing the second battery charging control procedure. [Figure 8] This flowchart shows the second warm-up control procedure for the battery, corresponding to the second charge control procedure. [Figure 9A] This is a flowchart of subprocess G. [Figure 9B] This is a flowchart of subprocess H. [Figure 9C] This is a flowchart of subprocess I. [Figure 10]This is a schematic diagram showing the procedure for determining the battery warm-up sequence and the procedure for extracting the warm-up completion temperature. [Figure 11] This flowchart shows the procedure for calculating the predicted charge amount at a given time. [Figure 12] This figure shows the time-series change in SOC when the warm-up completion temperature and warm-up sequence are changed. [Figure 13] This figure shows the time change in battery temperature when the high-temperature battery module is warmed up first. [Figure 14] This figure shows the time-series change of SOC when the high-temperature battery module is warmed up first. [Figure 15] This is a schematic diagram of another battery module, including a battery temperature control device. [Figure 16] This figure shows the differences between the battery charging control procedure according to Embodiment 2 and the battery charging control procedure according to Embodiment 1. [Figure 17] This figure shows the differences between the battery warm-up control procedure according to Embodiment 2 and the battery warm-up control procedure according to Embodiment 1. [Figure 18] This flowchart shows the procedure for calculating the predicted charging time until the target SOC is reached. [Figure 19] This figure shows the time-series change in the SOC of battery modules A and B when the high-temperature battery module is warmed up first. [Modes for carrying out the invention]

[0011] The embodiments of this disclosure will be described below with reference to the drawings. The following description of preferred embodiments is illustrative in nature and is not intended to limit this disclosure, its applications, or its uses.

[0012] (Embodiment 1) [1: Configuration of key components of electrical circuits in a vehicle] Figure 1 is a schematic diagram of the main part of the high-voltage circuit of the vehicle according to Embodiment 1. Figure 2 is a functional block diagram showing the configuration of the charging control device. For the sake of explanation, in Figures 1 and 2, electrical components and control circuits that are not directly related to the battery modules 2A and 2B are not shown or described.

[0013] As shown in Figure 1, the high-voltage circuit in vehicle 1 includes two sets of battery modules 2A and 2B, two sets of DC-DC converters 4A and 4B, two sets of circuit changeover switches 7A and 7B, an inverter 5, and a motor 6. In the following description, battery modules 2A and 2B may be referred to as mod(A) and mod(B). Also, mod(A), mod(B), or multiple battery modules may be collectively referred to simply as batteries or secondary batteries.

[0014] When vehicle 1 is running, both circuit selector switches 7A and 7B are closed. Mod(A) and mod(B) are connected to inverter 5, and their respective voltages are adjusted by DC-DC converters 4A and 4B before being input to inverter 5. The DC power input to inverter 5 is converted to AC power, which becomes the driving power for motor 6. Driving motor 6 causes vehicle 1 to move. Note that when fully charged, the voltages of mod(A) and mod(B) are approximately several hundred volts.

[0015] On the other hand, when charging mod(A) and mod(B), both circuit selector switches 7A and 7B are opened, and mod(A) and mod(B) are electrically connected to the rapid charger 31 provided in the charging equipment 30. mod(A) and mod(B) are charged by the charging current supplied from the rapid charger 31. DC-DC converters 4A and 4B have the function of adjusting the magnitude of the charging current supplied from the rapid charger 31 to mod(A) and mod(B). In other words, when charging mod(A) and mod(B), DC-DC converters 4A and 4B function as charging current adjusters.

[0016] As shown in Figure 2, the charging control device in vehicle 1 includes a battery system ECU (Electronic Control Unit) 10 and a PT system ECU 14. The battery system ECU 10 is also called a BECM (Battery Energy Control Module) 10. The PT system ECU 14 is also called a PCM (Power Control Module) 14. The BECM 10 and PCM 14 are each equipped with one or more CPUs (Central Processing Units; not shown). The BECM 10 and / or PCM 14 may also be provided with a storage unit (not shown) for storing parameters input by the user. This storage unit may temporarily store the parameters. Alternatively, this storage unit may be provided in vehicle 1 separately from the BECM 10 and PCM 14.

[0017] The BECM10 is connected to a battery temperature sensor 11, a battery voltage sensor 12, and a battery current sensor 13. Each of these is provided for a separate battery module.

[0018] In the example shown in Figures 1 and 2, a battery temperature sensor 11 is provided for both mod(A) and mod(B), detecting the temperature of mod(A) and mod(B). A battery voltage sensor 12 is provided for both mod(A) and mod(B), detecting the voltage of mod(A) and mod(B). A battery current sensor 13 is provided for both mod(A) and mod(B), detecting the current of mod(A) and mod(B). In other words, the temperature, voltage, and current of mod(A) and mod(B) are input to the BECM 10.

[0019] Furthermore, BECM10 is configured to exchange signals with the charging equipment 30. The charging equipment 30 receives setting conditions for charging mod(A) and mod(B) via an input unit (not shown in detail) from the user or the operator of the charging equipment, and these setting conditions are then input to BECM10. Based on the input setting conditions and the values ​​detected by each sensor 11-13, BECM10 generates control signals for DC-DC converters 4A and 4B and transmits them to PCM14. In addition, the charging status of mod(A) and mod(B), such as the SOC (State of Charge) of mod(A) and mod(B) at time t, is sent from BECM10 to the charging equipment 30 and displayed on a display unit (not shown). Therefore, the user can check the charging status of mod(A) and mod(B) by the information displayed on the display unit.

[0020] The PCM14 is electrically connected to circuit selector switches 7A and 7B, DC-DC converters 4A and 4B, and inverter 5, and the PCM14 controls the operation of each of them. For example, as mentioned above, the control signals for DC-DC converters 4A and 4B generated by BECM10 are sent from the PCM14 to DC-DC converters 4A and 4B, respectively.

[0021] Furthermore, the PCM14 is connected to flow path switching valves 26A and 26B (see Figure 3), a heater 21, and a fluid pump 22, and the PCM14 controls the operation of each of them. The operation and function of the flow path switching valves 26A and 26B, the heater 21, and the fluid pump 22 will be explained later.

[0022] Furthermore, BECM10 and PCM14 are configured to exchange signals with each other. The power for driving BECM10 and PCM14 is supplied from a low-voltage battery (not shown). In most cases, the DC voltage supplied from mod(A) and mod(B) is converted to a low voltage by a DC-DC converter, and the converted power is used to charge the low-voltage battery.

[0023] [2: Configuration of the battery module including the battery temperature control device] Figure 3 is a schematic diagram of a battery module including a battery temperature control device.

[0024] As shown in Figure 3, mod(A) and mod(B) each have multiple battery cells 3. The multiple battery cells 3 are arranged in a matrix, and in the example shown in Figure 3, there are 7 rows and 3 columns, or 21 battery cells, per battery module. The battery cells 3 are rechargeable and dischargeable, and for example, the battery cells 3 are lithium-ion secondary batteries.

[0025] Furthermore, a temperature control plate 23 (hereinafter referred to as "temperature control plate 23") is attached to each of the multiple battery cells 3. The branch pipes are arranged every two rows in the battery cells 3. In other words, two battery cells 3 are arranged to be in contact with one temperature control plate 23.

[0026] Furthermore, a first main pipe 24A is provided on one side of mod(A) and mod(B), and a second main pipe 24B is provided on the other side, with branch pipes 25A and 25B connecting the first main pipe 24A and the second main pipe 24B. The first main pipe 24A is supplied with heated water discharged from the fluid pump 22 after being heated to a predetermined temperature by the heater 21. A flow path switching valve 26A is provided at the connection point between the first main pipe 24A and the branch pipe 25A. A flow path switching valve 26B is provided at the connection point between the second main pipe 24B and the branch pipe 25B. In the example shown in Figure 3, the branch pipe 25A branches into four from the flow path switching valve 26A, extending in the row direction in the arrangement of the battery cells 3 and connecting at four points to the second main pipe 24B located on the opposite side of the flow path switching valve 26A, with the battery cells 3 in between. When the flow path switching valve 26A is open, heated water is supplied from the first main pipe 24A to each of the four branch pipes 25A. The heated water flowing through the four branch pipes 25A is supplied to each of the temperature control plates 23 arranged in the direction of travel, raising the temperature of the battery cells 3 in contact with the temperature control plates 23. The heated water flowing through the branch pipes 25A is collected in the second main pipe 24B, reheated to a predetermined temperature in the heater 21, and then supplied to the first main pipe 24A from the fluid pump 22.

[0027] Similarly, the branch pipe 25B branches off from the flow path switching valve 26B into four pipes, extending in the row direction in the arrangement of battery cells 3 and connecting at four points to the second main pipe 24B located on the opposite side of the flow path switching valve 26B, flanking the battery cells 3. The heated water flowing through the four branch pipes 25B is supplied to each of the temperature control plates 23, which are arranged in the row direction, raising the temperature of the battery cells 3 in contact with the temperature control plates 23. The heated water flowing through the branch pipes 25B is collected in the second main pipe 24B, reheated to a predetermined temperature in the heater 21, and then supplied to the first main pipe 24A by the fluid pump 22.

[0028] As is clear from Figure 3, the battery cells 3 included in mod(A) are heated by heated water flowing through four branch pipes 25A. Similarly, the battery cells 3 included in mod(B) are heated by heated water flowing through four branch pipes 25B. In other words, the battery module described in this specification constitutes a collection of battery cells 3 that are warmed by heated water flowing through the same flow path switching valve, i.e., a battery pack.

[0029] Note that the number of battery cells 3 and the number of rows of cells included in the battery module are not limited to the example shown in Figure 3 and can be changed as appropriate. The number of branch pipes 25A and 25B can also be changed as appropriate in accordance with the changes in the number of battery cells 3 and the number of rows of cells.

[0030] Furthermore, the heater 21, the fluid pump 22, and the temperature control plate 23 function as a battery temperature control device 20 (hereinafter referred to as the battery temperature control device 20) that adjusts the temperatures of mod(A) and mod(B). In addition, the flow path switching valves 26A and 26B, which are used to determine whether to warm up mod(A) or mod(B), are also part of the battery temperature control device 20.

[0031] Furthermore, a heater or a heat pump can be used as the heater 21. Also, as shown in this embodiment, when heated water is supplied to the temperature control plate 23, the fluid pump 22 is a water pump.

[0032] Furthermore, the battery temperature sensors 11 provided in mod(A) and mod(B), the battery temperature control device 20, the DC-DC converters 4A and 4B connected to mod(A) and mod(B) respectively, and the BECM 10 and PCM 14 are sometimes collectively referred to as the charging control device 40.

[0033] [3: Relationship between SOC and charging current in battery modules] Figure 4 is a schematic diagram showing the relationship between SOC and charging current in a battery module. As shown in Figure 4, when charging a battery module, the charging current that can be supplied changes significantly depending on the temperature of the battery module (hereinafter referred to as battery temperature). Furthermore, the charging current that can be supplied also changes significantly depending on the value of the SOC of the battery module. For example, when the battery temperature is low, the value of the charging current that can be supplied to the battery module is low and remains almost constant until the SOC reaches 100%. On the other hand, when the battery temperature is medium, the value of the charging current that can be supplied to the battery module can be higher than in the case of low temperature. Furthermore, the value of the charging current that can be supplied remains almost constant until the SOC reaches about 70%, and after the SOC exceeds 70%, it decreases with increasing SOC. Furthermore, when the battery temperature is high, the value of the charging current that can be supplied to the battery module can be significantly higher than in the case of medium temperature. Furthermore, the value of the charging current that can be supplied remains almost constant until the SOC reaches about 50%, and after the SOC exceeds 50%, it decreases with increasing SOC.

[0034] As can be seen from the above, when charging mod(A) and mod(B), the lower their respective temperatures, the lower the charging current needs to be. From another perspective, when charging mod(A) and mod(B), raising their respective temperatures from the beginning of charging when the SOC is low allows for charging with a high charging current, thus shortening the charging time. On the other hand, because the heat capacity of mod(A) and mod(B) is large, even if they are warmed up with the aforementioned heated water, the temperatures of mod(A) and mod(B) do not rise rapidly. By the time the temperature has risen to a certain level, charging of mod(A) and mod(B) is already underway, so the effect of warming up to shorten the charging time (temperature control effect) becomes smaller.

[0035] In light of these considerations, the inventors of the present invention have found that when the temperature of multiple battery modules mounted on vehicle 1 is low, instead of heating all battery modules simultaneously, the order in which the battery modules are warmed up can be determined based on multiple parameters related to the battery modules, thereby improving the charging performance of the battery pack compared to conventional methods. This will be explained below with reference to the drawings.

[0036] [4: First charging control procedure and warm-up control procedure for the battery module] Figure 5 is a flowchart of the first battery charge control procedure and warm-up control procedure. Figure 6A is a flowchart of sub-process A. Figure 6B is a flowchart of sub-process B. Figure 6C is a flowchart of sub-process C. Figure 6D is a flowchart of sub-process D. Figure 6E is a flowchart of sub-process E. Figure 6F is a flowchart of sub-process F. In this embodiment, the user can set the charging time t of mod(A) and mod(B). user This is pre-set. Depending on the number of battery cells 3, etc., charging mod(A) and mod(B) takes time, so in actual charging, the charging time t user This setting is often used to shorten charging time.

[0037] Furthermore, in the following explanation, among mod(A) and mod(B), the one with the higher battery temperature may be referred to as mod(H), and the one with the lower battery temperature may be referred to as mod(L). Note that in this embodiment, it is not a prerequisite that the battery temperature of mod(H) and the battery temperature of mod(L) be the same.

[0038] The BECM10 receives a command to start rapid charging mod(H) and mod(L) based on the operation of a worker, including the user. As shown in Figure 4, the BECM10 sets the lowest battery temperature T detected by the battery temperature sensors 11 provided for mod(H) and mod(L). min However, the threshold temperature T is the temperature at which one can determine whether or not warming up the engine is necessary. heat Determine whether it is lower than or equal to (Step S1).

[0039] If the determination in step S1 is negative, that is, both mod(H) and mod(L) are at a temperature T heat above the battery temperature, the process proceeds to sub-process E (see FIG. 6E).

[0040] On the other hand, if the determination in step S1 is affirmative, that is, at least the battery temperature of mod(L) is lower than the temperature T heat BECM10 determines whether the highest temperature T among the battery temperatures detected by the battery temperature sensor 11 max is lower than the temperature T heat (step S2).

[0041] If the determination in step S2 is negative, that is, mod(L) is lower than the temperature T heat but the battery temperature of mod(H) is at or above the temperature T heat the process proceeds to sub-process F (see FIG. 6F).

[0042] On the other hand, if the determination in step S2 is affirmative, that is, the battery temperatures of both mod(H) and mod(L) are lower than the temperature T heat BECM10 determines whether the temperature T of mod(H) mod(H) is lower than the first temperature T1 (>T heat )(step S3). Here, the first temperature T1 is a threshold temperature for determining the warm-up order of mod(H) and mod(L). This will be described later.

[0043] If the determination in step S3 is negative, that is, the temperature T of mod(H) mod(H) is higher than the first temperature T1, a predicted charge calculation of the battery module is executed based on a plurality of parameters related to the battery module (step S6). Note that the processing in step S6 is executed by BECM10. Also, the predicted charge calculation in step S6 is executed on the condition that warm-up is performed in the order of mod(L) → mod(H).

[0044] After step S6 is completed, BECM10 then sets the battery module to a warm-up completion temperature T end2 Calculate the warm-up completion temperature T (step S7). end2 This refers to the aforementioned charging time t set by the user. user This is the battery temperature at which the maximum charge can be secured. After step S7 is executed, the process proceeds to subprocess C (see Figure 6C), and after the execution of subprocess D (see Figure 6D), the mod(H) and mod(L) rapid charging is terminated.

[0045] On the other hand, if the judgment in step S3 is positive, that is, if the temperature T modulo (H) is positive, mod(H) If the temperature is lower than the first temperature T1, a charge amount prediction calculation for the battery module is performed based on several parameters related to the battery module (step S4). Note that the process in step S3 is performed in BECM10. Furthermore, the charge amount prediction calculation in step S4 is performed on the condition that warm-up is performed in the order mod(H) → mod(L).

[0046] After step S4 is completed, BECM10 then sets the battery module to a warm-up completion temperature T. end1 Calculate (Step S5). Warm-up completion temperature T end1 is the warm-up completion temperature T end2 Similarly, charging time T use1 This is the battery temperature at which the maximum charge can be secured. After step S5 is executed, the process proceeds to subprocess A (see Figure 6A), and after the execution of subprocess B (see Figure 6B), the mod(H) and mod(L) rapid charging is terminated. The processes of steps S4 to S7 will be described in detail later.

[0047] [4-1: Regarding charge control when warming up from the high-temperature side of the battery module] Figure 6A is a flowchart of subprocess A. Figure 6B is a flowchart of subprocess B. As mentioned above, subprocess A and subprocess B are charge control procedures and warm-up control procedures when warming up in the order mod(H) → mod(L), that is, when warming up from the hottest battery module among multiple battery modules.

[0048] [4-1-1: Subprocess A] Subprocess A is executed in the following steps. After step S5 is performed, mod(H) is warmed up and charging of both mod(H) and mod(L) is started (step S8). Next, BECM10 calculates that the elapsed time t from the start of charging is the charging time t. user Determine whether it is shorter or shorter (Step S9).

[0049] If the result of step S9 is negative, that is, the elapsed time t from the start of charging is the aforementioned charging time t. user If the required level is reached, both mod(H) and mod(L) charging will be terminated.

[0050] If the judgment result in step S9 is positive, that is, the elapsed time t from the start of charging is equal to the charging time t user If it does not reach this level, BECM10 determines whether both mod(H) SOC(SOC(H)) and mod(L) SOC(SOC(L)) are less than 95% (step S10).

[0051] If the result of step S10 is positive, then the next step is to determine the battery temperature T modulo (H). mod(H) The warm-up completion temperature T calculated in step S5 end1 It is determined whether the value is higher or lower (step S11). The detection result from the battery temperature sensor 11 is used for the determination in step S11.

[0052] The result of the judgment in step S11 is positive, that is, the battery temperature T mod(H) is the warm-up completion temperature T end1 If it is higher than mod(H), the warm-up of mod(L) is terminated and the warm-up of mod(L) is started (step S12), and the process proceeds to subprocess B. If the judgment result of step S11 is negative, that is, the battery temperature T mod(H) is the warm-up completion temperature T end1 If the following conditions are met, return to step S9 and repeatedly execute the series of processes from steps S9 to S11 until the judgment result in step S11 is positive.

[0053] On the other hand, if the result of the judgment in step S10 is negative, that is, if either SOC(H) or SOC(L) is 95% or more, BECM10 determines whether or not SOC(L) is above 95% (step S13). If the result of the judgment in step S13 is negative, that is, if SOC(L) is 95% or less, the warm-up and charging of mod(H) is terminated (step S16), the process proceeds to step S12 to start the warm-up of mod(L), and then proceeds to subprocess B.

[0054] If the result of step S13 is positive, BECM10 determines whether or not SOC(H) exceeds 95% (step S14). If the result of step S14 is positive, warm-up and charging of mod(H) are terminated, and charging of mod(L) is terminated (step S15). In other words, rapid charging of mod(H) and mod(L) is terminated.

[0055] On the other hand, if the result of the judgment in step S14 is negative, that is, if SOC(H) is 95% or less, the charging of mod(L) is terminated (step S17), and the battery temperature T of mod(H) is determined. mod(H) is the warm-up completion temperature T end1 It is determined whether the value is higher or lower (step S18). The detection result from the battery temperature sensor 11 is used for the determination in step S18.

[0056] The result of the judgment in step S18 is negative, meaning that the battery temperature T mod(H) is the warm-up completion temperature T end1 If the following conditions are met, return to step S9 and repeatedly execute the series of processes from steps S9 to S11 until the judgment result in step S11 is positive.

[0057] If the result of the judgment in step S18 is positive, the warm-up of mod(H) is terminated (step S19), and then the process returns to step S9 and the series of processes from steps S9 to S11 are repeatedly executed until the result of the judgment in step S11 is positive.

[0058] [4-1-2: Subprocess B] Subprocess B is executed according to the following procedure. After step S12 is executed, BECM10 determines that the elapsed time t from the start of charging is the charging time t. user Determine whether it is shorter or shorter (step S20).

[0059] If the result of step S20 is negative, that is, the elapsed time t from the start of charging is the charging time t user If the required level is reached, both mod(H) and mod(L) charging will be terminated.

[0060] If the judgment result in step S20 is positive, that is, the elapsed time t from the start of charging is equal to the charging time t user If it does not reach this level, BECM10 determines whether both SOC(H) and SOC(L) are less than 95% (step S21).

[0061] If the result of step S21 is positive, then the next step is to determine the battery temperature T modulo (L). mod(L) is the warm-up completion temperature T end1 It is determined whether the value is higher or lower (step S22). The detection result from the battery temperature sensor 11 is used for the determination in step S22.

[0062] The judgment result in step S22 is positive, that is, the battery temperature T mod(L) is the warm-up completion temperature T end1 If it is higher than that, the warm-up of mod(L) is terminated (step S23), and the process returns to step S20 and the process from step S20 onwards is executed again. If the result of the judgment in step S22 is negative, that is, the battery temperature T mod(L) is the warm-up completion temperature T end1 If the following conditions are met, the process returns to step S20 and the series of operations from steps S20 to S22 are repeatedly executed until the judgment result in step S22 is positive.

[0063] On the other hand, if the result of the judgment in step S21 is negative, that is, if either SOC(H) or SOC(L) is 95% or higher, BECM10 determines whether or not SOC(H) is above 95% (step S24). If the result of the judgment in step S24 is negative, that is, if SOC(H) is 95% or less, the warm-up and charging of mod(L) is terminated (step S27), and the process returns to step S20, and the processing from step S20 onwards is executed again.

[0064] If the result of step S24 is positive, BECM10 determines whether the SOC(L) exceeds 95% (step S25). If the result of step S25 is positive, the warm-up and charging of mod(L) is terminated, and the charging of mod(H) is terminated (step S26). In other words, the rapid charging of mod(H) and mod(L) is terminated.

[0065] On the other hand, if the result of the judgment in step S25 is negative, that is, if SOC(L) is 95% or less, the charging of mod(H) is terminated (step S28), and the battery temperature T of mod(L) is determined. mod(H) is the warm-up completion temperature T end1 It is determined whether the value is higher or lower (step S29). The detection result from the battery temperature sensor 11 is used for the determination in step S29.

[0066] The result of the judgment in step S29 is negative, meaning that the battery temperature T mod(L) is the warm-up completion temperature T end1 If the following conditions are met, the process returns to step S20 and the series of operations from steps S20 to S22 are repeatedly executed until the judgment result in step S22 is positive.

[0067] If the result of the judgment in step S29 is positive, the warm-up of mod(L) is terminated (step S30), and then the process returns to step S20 and the series of processes from steps S20 to S22 are repeatedly executed until the result of the judgment in step S22 is positive.

[0068] [4-2: Charging control when warming up from the low-temperature battery module] Figure 6C is a flowchart of subprocess C. Figure 6D is a flowchart of subprocess D. As mentioned above, subprocesses C and D are the charge control procedure and warm-up control procedure when warming up in the order mod(L) → mod(H), that is, when warming up from the coldest battery module among multiple battery modules.

[0069] The processing procedure for subprocess C shown in Figure 6C, that is, the processing from steps S31 to S42, follows the same flow as the processing procedure for subprocess A shown in Figure 6A, that is, the processing from steps S8 to S19. Similarly, the processing procedure for subprocess D shown in Figure 6D, that is, the processing from steps S43 to S53, follows the same flow as the processing procedure for subprocess B shown in Figure 6B, that is, the processing from steps S20 to S30.

[0070] However, unlike subprocesses A and B, the warm-up process starts with the coldest battery module among the multiple battery modules, so the content of each step in subprocesses C and D may differ from that of subprocesses A and B.

[0071] Specifically, in subprocesses A and B, any processing performed individually with respect to mod(H) is replaced by processing performed individually with respect to mod(L) in subprocesses C and D. Similarly, in subprocesses A and B, any processing performed individually with respect to mod(L) is replaced by processing performed individually with respect to mod(H) in subprocesses C and D.

[0072] For example, the start of warm-up mod(H) in step S8 is replaced with the start of warm-up mod(L) in step S31. Also, the end of warm-up mod(L) in step S23 is replaced with the end of warm-up mod(H) in step S46.

[0073] Furthermore, in subprocesses A and B, the processing related to the modulo(H) parameter is replaced by processing related to the modulo(L) parameter in subprocesses C and D. Similarly, in subprocesses A and B, the processing related to the modulo(L) parameter is replaced by processing related to the modulo(H) parameter in subprocesses C and D.

[0074] For example, the battery temperature T modulo (H) in step S11 mod(H) and warm-up completion temperature T end1 The process for determining the relative magnitude of the two is performed in step S34, where the battery temperature T mod(L) is determined. mod(L) and warm-up completion temperature Tend2 This can be replaced by a process of determining the relative magnitude of the two. Also, the battery temperature T mod(L) in step S22 mod(L) and warm-up completion temperature T end1 The process for determining the relative magnitude of the two is performed in step S45, where the battery temperature T mod(H) is determined. mod(H) and warm-up completion temperature Tend2 This can be replaced by a process of determining the relative size of two things.

[0075] [4-3: Regarding charge control when the engine is not warmed up] Figure 6E is a flowchart of subprocess E. Subprocess E is a charge control procedure and a warm-up control procedure for multiple battery modules when no warm-up is performed.

[0076] In step S1, both mod(H) and mod(L) are at temperature T. heat If the temperature is determined to be above the above, charging is started for both mod(H) and mod(L) (step S54). Next, BECM10 calculates that the elapsed time t from the start of charging is the charging time t. user Determine whether it is shorter or shorter (step S55).

[0077] If the judgment result in step S55 is negative, that is, the elapsed time t from the start of charging is the charging time t user If the required level is reached, both mod(H) and mod(L) fast charging will be terminated.

[0078] If the judgment result in step S55 is positive, that is, the elapsed time t from the start of charging is equal to the charging time t user If it does not reach this level, BECM10 determines whether either SOC(H) or SOC(L) exceeds 95% (step S56).

[0079] If the result of the judgment in step S56 is negative, the process returns to step S55 and steps S55 and S56 are repeated until the result of the judgment in step S57 is positive.

[0080] If the result of the judgment in step S56 is positive, BECM10 determines whether or not SOC(H) exceeds 95% (step S57). If the result of the judgment in step S58 is negative, charging of mod(L) is terminated (step S60), and the process returns to step S55, and the series of processes from steps S55 to S57 are repeated until the result of the judgment in step S58 is positive.

[0081] On the other hand, if the result of the judgment in step S57 is positive, BECM10 determines whether or not SOC(L) exceeds 95% (step S58). If the result of the judgment in step S58 is negative, charging of mod(H) is terminated (step S61), and the process returns to step S55, and the series of processes from steps S56 to S59 are repeated until the result of the judgment in step S58 is positive. If the result of the judgment in step S58 is positive, rapid charging of both mod(H) and mod(L) is terminated (step S59).

[0082] [4-4: Regarding charge control when warming up only in mod(L)] Figure 6F is a flowchart of subprocess F. Subprocess F is the charge control procedure and warm-up control procedure when warm-up is performed only for mod(L).

[0083] The processing procedure for subprocess F shown in Figure 6F, that is, the processing from steps S62 to S73, follows the same flow as the processing procedure for subprocess C shown in Figure 6C, that is, the processing from steps S31 to S42.

[0084] However, unlike subprocess C, only the low-temperature battery modules among the multiple battery modules are warmed up in subprocess F, so the content of each step in subprocess F may differ from that of subprocess C.

[0085] Specifically, in subprocess F, any processing performed individually with respect to mod(H) is replaced by processing related to the charging of mod(H) in subprocess C. Similarly, in subprocess F, any processing performed individually with respect to mod(L) is replaced by processing performed individually with respect to mod(L) in subprocess C.

[0086] For example, the warm-up of mod(H) in step S35 is omitted in step S66.

[0087] Furthermore, in subprocess F, the processing related to the mod(H) parameter is replaced in subprocess C with processing related to the mod(H) parameter, excluding the temperature used for the warm-up process. Also, in subprocess F, the processing related to the mod(L) parameter is replaced in subprocess C with processing related to the mod(L) parameter.

[0088] For example, in step S38, the process of ending the warm-up and charging of mod(H) and ending the charging of mod(L) can be replaced in step S69 with the process of ending the warm-up and charging of mod(L) and ending the charging of mod(H).

[0089] [5: Second charging control procedure and warm-up control procedure for the battery module] Figure 7 is a flowchart of the second charge control procedure for the battery. Figure 8 is a flowchart of the second warm-up control procedure for the battery, corresponding to the second charge control procedure. Figures 9A to 9C are flowcharts of subprocesses G to I.

[0090] As shown in Figure 7, in the second charge control procedure, the BECM 10 reads the battery temperature and SOC of mod(A) and mod(B) based on the detection results of the battery temperature sensor 11, the battery voltage sensor 12, and the battery current sensor 13 (step S80). Then, based on the charge current map described later, it starts charging both mod(A) and mod(B) (step S81). Next, the BECM 10 determines that the elapsed time t from the start of charging is the charging time t. user It is determined whether it is shorter than (step S82). If the result of the determination in step S82 is positive, BECM10 determines whether either SOC(A) or SOC(B) exceeds 95% (step S83). On the other hand, if the result of the determination in step S82 is negative, that is, the elapsed time t from the start of charging is less than the charging time t user If the target is reached, both mod(A) and mod(B) fast charging will be terminated.

[0091] If the result of the judgment in step S83 is positive, BECM10 determines whether both SOC(A) and SOC(B) exceed 95% (step S84). On the other hand, if the result of the judgment in step S83 is negative, that is, if neither SOC(A) nor SOC(B) exceeds 95%, the process returns to step S80 and the series of processes from steps S80 to S83 are repeatedly executed until the result of the judgment in step S83 becomes positive.

[0092] If the result of step S84 is positive, the rapid charging of both mod(A) and mod(B) is terminated. On the other hand, if the result of step S84 is negative, the rapid charging of the battery module whose SOC exceeds 95% is terminated (step S85), and the process returns to step S80, repeating the series of processes from steps S80 to S84 until the result of step S84 is positive.

[0093] The battery charging control procedure shown in Figure 7 and the battery warm-up control procedure shown in Figures 8, 9A-9C correspond to the battery charging control procedure and warm-up control procedure shown in Figures 5 and 6A-6F. However, in the flowchart shown in Figure 5, in steps S1 and S2, the temperature T min is temperature T heat Whether it is lower than or equal to, and the temperature T max is temperature T heat The system determines whether the value is lower than or equal to a certain value, and based on these determinations, it decides the warm-up order of the battery modules. On the other hand, in the flowchart shown in Figure 8, the warm-up order of the battery modules is determined according to the relationship between the maximum charge values ​​ΔSOC(H) and ΔSOC(L), which will be explained later. This will be explained below.

[0094] As shown in Figure 8, the BECM10 reads various parameters entered by the operator, including the user (step S90). These parameters are the initial temperatures of mod(A) and mod(B), the initial SOC, the amount of heat added for warming up, and the heat capacities of mod(A) and mod(B). Step S80, shown in Figure 7, corresponds to a part of step S90. The target charging time (target charging time) is also entered. Note that the heating rate may be entered instead of the amount of heat.

[0095] Next, BECM10 determines whether both mod(A) and mod(B) are not yet warmed up (step S91). Step S91 is determined based on the detection result of the battery temperature sensor 11. If the determination result of step S91 is negative, that is, if at least one of mod(A) and mod(B) is warmed up, the process proceeds to subprocess I.

[0096] If the result of step S91 is positive, meaning that neither mod(A) nor mod(B) are warmed up, the BECM10 performs a prediction calculation of the charge amount based on the various parameters read in step S90 and the heat capacities of mod(A) and mod(B) described above (step S92). This calculation is performed by varying the warm-up completion temperature within a predetermined temperature range in a pattern where warm-up starts from mod(H) as described above. In addition, as a result of the prediction calculation, the maximum charge amount ΔSOC is calculated. max(H) This is extracted. Furthermore, ΔSOC max(H) The warm-up completion temperature T end(H) This is extracted and stored in the aforementioned memory unit.

[0097] After step S92 is executed, the BECM10 performs a prediction calculation of the charge amount based on the various parameters read in step S90, the charging current map described later, and the thermal capacities of mod(A) and mod(B) (step S93). This calculation is performed by varying the warm-up completion temperature within a predetermined temperature range in a pattern where warm-up starts from mod(L) as described above. As a result of the prediction calculation, the maximum charge amount ΔSOC is calculated. max(L) This is extracted. Furthermore, ΔSOC max(L) The warm-up completion temperature T end(L) This is extracted and stored in the aforementioned memory unit.

[0098] The processes in steps S92 and S93 correspond to the processes in steps S4 to S7 described above. Details of these processes will be described later. The thermal capacity and charging current map are stored in the memory beforehand and are read by the CPU in the BECM10 when executing steps S92 and S93. The thermal capacity may also be input by the user in step S90.

[0099] Next, BECM10 is ΔSOC max(H) ΔSOC max(L) Determine whether it is greater than or equal to (step S94). If the result of the determination in step S94 is positive, proceed to subprocess G; otherwise, proceed to subprocess H.

[0100] [5-1: Subprocess G] Subprocess G is a warm-up control procedure for when the warm-up of multiple battery modules is incomplete and the warm-up is performed in the order mod(H) → mod(L), that is, starting with the high-temperature battery module.

[0101] ΔSOC max(H) ΔSOC max(L) If it is greater than or equal to, the PCM14 starts warming up from mod(H) (step S95). Subsequently, the BECM10 reads the battery temperatures mod(H) and mod(L) respectively and calculates the SOC (step S96). The battery temperature is read from the detection result of the battery temperature sensor 11, and the SOC is calculated based on the detection results of the battery voltage sensor 12 and the battery current sensor 13.

[0102] Next, BECM10 determines whether the SOC(H) is less than 95% (step S97). If the result of step S97 is positive, the process proceeds to step S98. On the other hand, if the result of step S97 is negative, that is, if the SOC(H) is 95% or more, the process proceeds to step S99, where the warm-up of mod(H) is terminated and the warm-up of mod(L) is started.

[0103] In step S98, the battery temperature T modulo (H) mod(H) The warm-up completion temperature T was extracted in step S92. end(H) It is determined whether the above is true or not. If the result of the determination in step S98 is positive, the process proceeds to step S99, where the warm-up of mod(H) is terminated and the warm-up of mod(L) is started. On the other hand, if the result of the determination in step S98 is negative, that is, the battery temperature T mod(H) is the warm-up completion temperature T end(H) If the result is lower than that, the process returns to step S96 and the sequence of steps S96 to S98 is repeated until the result of the judgment in step S98 is positive.

[0104] After step S99 is executed, BECM10 determines whether SOC(L) is less than 95% (step S100). If the result of step S100 is positive, the process proceeds to step S101. On the other hand, if the result of step S100 is negative, that is, if SOC(L) is 95% or more, both mod(H) and mod(L) warm-up are terminated.

[0105] In step S101, the SOC modulo(L), i.e., SOC(L), is calculated. Furthermore, BECM10 calculates the elapsed time t from the start of charging as the target charging time t entered by the user in step S90. user Determine whether it is shorter than or equal to the target charging time t (step S102). If the result of the determination in step S102 is positive, proceed to step S103. If the result of the determination in step S102 is negative, that is, if the elapsed time t is shorter than or equal to the target charging time t user If the condition is reached, the warm-up of mod(L) is terminated (step S104), and the warm-up of both mod(H) and mod(L) is terminated.

[0106] In step S103, it is determined whether or not SOC(L) exceeds 95%. If the result of the determination in step S103 is positive, the warm-up of mod(L) is terminated (step S104), and the warm-up of both mod(H) and mod(L) is terminated. On the other hand, if the result of the determination in step S103 is negative, that is, if SOC(L) is 95% or less, the process returns to step S101 and the series of processes from steps S101 to S103 are repeatedly executed until the result of the determination in step S103 becomes positive.

[0107] [5-2: Subprocess H] Subprocess H is a warm-up control procedure for when the warm-up of multiple battery modules is incomplete and the warm-up is performed in the order mod(L) → mod(H), that is, starting with the coldest battery module.

[0108] The processing procedure for subprocess H shown in Figure 9B, that is, the processing from steps S105 to S114, follows the same flow as the processing procedure for subprocess G shown in Figure 9A, that is, the processing from steps S95 to S104.

[0109] However, unlike subprocess G, subprocess H warms up the battery modules starting from the coldest ones among the multiple battery modules, so the content of each step in subprocess H may differ from that of subprocess G.

[0110] Specifically, any processing performed individually with respect to mod(H) in subprocess G is replaced by processing performed individually with respect to mod(L) in subprocess H. Similarly, any processing performed individually with respect to mod(L) in subprocess G is replaced by processing performed individually with respect to mod(H) in subprocess H.

[0111] For example, the process of starting warm-up from mod(H) in step S95 is replaced in step S105 with the process of starting warm-up from mod(L). Also, the process of ending warm-up of mod(H) and starting warm-up of mod(L) in step S99 is replaced in step S109 with the process of ending warm-up of mod(L) and starting warm-up of mod(H).

[0112] Furthermore, in subprocess G, the processing related to the modulo(H) parameter is replaced by the processing related to the modulo(L) parameter in subprocess H. Similarly, in subprocess G, the processing related to the modulo(L) parameter is replaced by the processing related to the modulo(H) parameter in subprocess H.

[0113] For example, the battery temperature T modulo (H) in step S98 mod(H) and warm-up completion temperature T end(H) The process for determining the relative magnitude of the two is performed in step S108, where the battery temperature T mod(L) is determined. mod(L) and warm-up completion temperature Tend(L) This is replaced by a judgment process regarding the relative magnitude of the two. Also, the judgment process regarding the range of SOC(L) in step S100 is replaced by a judgment process regarding the range of SOC(H) in step S110.

[0114] [5-3: Sub-process I] Sub-process I is a warm-up control procedure for performing warm-up on battery modules whose warm-up has not been completed when at least one of a plurality of battery modules has completed warm-up.

[0115] If the determination result in step S91 is negative, PCM14 or BECM10 determines whether there is a battery module whose warm-up has not been completed (step S115). If the determination result in step S115 is negative, the process proceeds to step S122. On the other hand, if the determination result in step S115 is positive, the warm-up of the battery module whose warm-up has not been completed is started (step S116), and the battery temperatures of mod(H) and mod(L) are read and the SOC is calculated in the same procedure as shown in step S96 (step S117).

[0116] Next, BECM10 determines whether the battery temperature T of the battery module whose warm-up has not been completed mod is below the warm-up completion temperature T end (step S118). The warm-up completion temperature T end is determined based on the aforementioned warm-up completion temperature T end(H) and warm-up completion temperature T end(L) .

[0117] If the determination result in step S118 is negative, that is, if the battery temperature T mod is higher than the warm-up completion temperature T end , the warm-up of the battery module with an SOC exceeding 95% is completed (step S121). On the other hand, if the determination result in step S118 is positive, next, BECM10 determines whether the elapsed time t from the start of charging is shorter than the target charging time t user (step S119). If the determination result in step S119 is positive, the process proceeds to step S120. If the determination result in step S119 is negative, that is, if the elapsed time t is the target charging time t userIf this is reached, proceed to step S121 to complete the warm-up of the battery module whose SOC is above 95%.

[0118] In step S120, BECM10 determines whether the SOC of the battery modules that have not yet warmed up exceeds 95%. If the result of the determination in step S120 is positive, the process proceeds to step S121 to complete the warm-up of the battery modules whose SOC exceeds 95%. On the other hand, if the result of the determination in step S120 is negative, the process returns to step S117 and the series of processes from steps S117 to S120 are repeatedly executed until the result of the determination in step S120 becomes positive.

[0119] After executing step S121, BECM10 determines whether there are any battery modules that have not yet warmed up (step S122). If the result of step S122 is negative, that is, if there are battery modules that have not yet warmed up, the process returns to step S117 and the series of processes from steps S117 to S122 are repeatedly executed until the result of step S122 becomes positive. On the other hand, if the result of step S122 is positive, that is, if there are no battery modules that have not yet warmed up, both mod(H) and mod(L) warm-up are terminated.

[0120] [6: Procedure for determining the battery warm-up sequence, the procedure for predicting the charge amount, and the procedure for extracting the warm-up completion temperature] Figure 10 is a schematic diagram showing the procedure for determining the battery warm-up sequence and the procedure for extracting the warm-up completion temperature. Figure 11 is a flowchart showing the procedure for predicting the charge amount at a predetermined time. Figure 12 shows the time-series change of SOC when the warm-up completion temperature and warm-up sequence are changed.

[0121] Figure 13 shows the time-series change in battery temperature when the high-temperature battery module is warmed up first. Figure 14 shows the time-series change in SOC when the high-temperature battery module is warmed up first. The comparative examples shown in Figures 13 and 14 show the time-series changes in battery temperature and SOC, respectively, when mod(H) and mod(L) are warmed up simultaneously.

[0122] The procedure for predicting the battery charge level corresponds to steps S92 and S93 in Figure 8. It also corresponds to steps S4 and S6 in Figure 5. The procedure for extracting the warm-up completion temperature corresponds to steps S92 and S93 in Figure 8. It also corresponds to steps S5 and S7 in Figure 5.

[0123] To determine the warm-up sequence for multiple battery modules and extract the warm-up completion temperature, initial input conditions (INPUT1) are determined as shown in Figure 10. Specifically, the SOC of the battery before charging (initial SOC), the battery temperature before charging (initial battery temperature), the charging current map, the amount of battery heating or the rate of heating rise, and the thermal capacity of the battery are input. The charging current map is numerical data that describes the relationship between SOC and charging current when the battery temperature is changed, and corresponds to the numerical data used to derive the graph shown in Figure 4.

[0124] Furthermore, the setting conditions for charging (INPUT2) are either the target charging time or the target SOC. In this embodiment, we consider the case where the target charging time is entered.

[0125] Once the initial input conditions and charging settings are entered, the BECM10 calculates the time-series change of SOC according to the process (Process A) shown in Figure 11. Figure 11 will be used for further explanation.

[0126] First, the charging current is calculated based on the charging current map, specifically the initial SOC and the initial battery temperature (step S130). Next, the amount of charge ΔSOC from the start of charging until Δt seconds have elapsed is calculated (step S131), and then the battery temperature Δt seconds after the start of charging is calculated based on the amount of heating and the heat capacity of the battery (step S132).

[0127] The series of processes from step S133 to step S136, which will be described below, will be executed (m-1) times. Here, the target charging time is t. user Therefore, m is the smallest integer that satisfies equation (1) below.

[0128] m×Δt≧t user ···(1) Based on the SOC and the battery temperature at time ti, the charging current is calculated (step S133). Next, the charge amount ΔSOC until Δt seconds have elapsed from time ti is calculated (step S134), and further, based on the heating amount and the heat capacity of the battery, the battery temperature after Δt seconds from time ti is calculated (step S135). The SOC at time t(i + 1) is calculated (step S136).

[0129] Also, as shown in FIG. 10, Process A is executed for each combination of the warm-up order, that is, the selection content such as whether to warm up from the high-temperature side battery module, from the low-temperature side battery module, or to warm up all battery modules equally or not, and the warm-up completion temperature. Further, as a result of the execution, a time-series change of the SOC, that is, a group of SOC time charts, when the warm-up completion temperature and the warm-up order are changed is obtained. FIG. 12 shows an example thereof.

[0130] As shown in FIG. 12, the SOC time chart changes depending on the warm-up completion temperature. Moreover, it has been found that the warm-up completion temperature at which a larger charge amount can be ensured also changes depending on the difference in the warm-up order. Also, it has been found that the warm-up completion temperature at which a larger charge amount can be ensured also changes according to the charging time.

[0131] Taking the example shown in FIG. 12, when the charging time is T1, the warm-up completion temperature at which the largest charge amount can be ensured is 30°C, whereas when the charging time is T2 (>T1), the warm-up completion temperature at which the largest charge amount can be ensured is 20°C.

[0132] Based on the group of SOC time charts obtained by the above-described procedure and the preset target charging time, the warm-up order and the warm-up completion temperature of the battery module are determined, and the execution results of the processes in steps S4 to S7 and the processes in steps S92 and S93 are obtained.

[0133] For example, when warming up the battery module starting from the high-temperature side, as shown in Figure 13, the warm-up completion temperature is appropriately selected according to the charging time, as shown in Figure 14, and the mod(H) and mod(L) charge control (see Figures 6A and 6B) and warm-up control (see Figure 9A) are executed sequentially.

[0134] As shown in the comparative example in Figure 13, compared to warming up mod(H) and mod(L) simultaneously, warming up from the high-temperature battery module, as shown in this embodiment (see Figure 13), allows both mod(H) and mod(L) to reach their warm-up completion temperatures in a shorter time. However, if the battery temperature Tmod(H) of mod(H) is higher than a predetermined value, the effect of warming up to shorten the charging time (temperature control effect) becomes smaller, as shown in Figure 4. Therefore, depending on the set charging time, warming up from the low-temperature battery module may result in a larger total charge amount for mod(H) and mod(L).

[0135] [7: Variations in battery module configuration] The number of battery modules installed in vehicle 1 is not particularly limited to the example shown in Figure 1. The number of battery modules can be changed as appropriate from the viewpoint of supplying the power required for vehicle 1 to run on a single charge.

[0136] Figure 15 is a schematic diagram of another battery module including a battery temperature control device. For example, four sets of battery modules may be provided as shown in Figure 15. The total number of battery cells 3 and temperature control plates 23 in battery modules 2A to 2D shown in Figure 15 is the same as mod(A) and mod(B) shown in Figure 3. On the other hand, in battery modules 2A and 2C shown in Figure 15, each battery module has 4 rows and 3 columns, i.e., 12 battery cells 3. Also, in battery modules 2B and 2C shown in Figure 15, each battery module has 3 rows and 3 columns, i.e., 9 battery cells 3.

[0137] By opening the flow path switching valve 26C and closing the flow path switching valves 26D, 26E, and 26F, heated water can be flowed through the two branch pipes 25D that extend in the direction of travel, which are closest to the heated water inlet, thereby warming up the battery module 2A. Alternatively, by opening the flow path switching valve 26D and closing the flow path switching valves 26C, 26E, and 26F, heated water can be flowed through the two branch pipes 25D that extend in the direction of travel, which are furthest from the heated water inlet, thereby warming up the battery module 2B.

[0138] By opening the flow path switching valve 26E and closing the flow path switching valves 26C, 26D, and 26F, heated water can be flowed through the two branch pipes 25C extending in the direction of travel that are closest to the heated water inlet, thereby warming up the battery module 2C. Alternatively, by opening the flow path switching valve 26F and closing the flow path switching valves 26C, 26D, and 26E, heated water can be flowed through the two branch pipes 25C extending in the direction of travel that are furthest from the heated water inlet, thereby warming up the battery module 2D.

[0139] The first charging control method and warm-up control method, or the second charging control method and warm-up control method, described above can be applied to multiple battery modules, including the battery module with the configuration shown in Figure 15. In this case, each battery module is provided with a battery temperature sensor 11, a battery voltage sensor 12, a battery current sensor 13, and a DC-DC converter. Multiple DC-DC converters are collectively referred to as DC-DC converter 4. If there are battery modules whose battery temperature is equal to or higher than the first temperature T1, warm-up is performed preferentially on the battery module with the highest battery temperature among the battery modules whose battery temperature is lower than the first temperature T1.

[0140] [8: Effects, etc.] As described above, the secondary battery charge control device 40 according to this embodiment includes at least a battery temperature sensor (battery temperature detection means) 11, a battery temperature control device 20, a DC-DC converter (charging current adjustment device) 4, a BECM 10, and a PCM 14.

[0141] The charging control device 40 controls the charging of multiple battery modules (batteries) installed in the vehicle 1, including warm-up control. The multiple battery modules are connected in parallel when in use, and are charged simultaneously from the charging equipment 30, which is an external power source.

[0142] The battery temperature sensor 11 and the DC-DC converter 4 are provided in each of the multiple battery modules. The DC-DC converter 4 is configured to adjust the charging current according to the battery temperature and the State of Charge (SOC). More specifically, the DC-DC converter 4 is configured to adjust the charging current value to be lower as the battery temperature decreases. Also, the DC-DC converter 4 is configured to adjust the charging current value to be lower as the SOC increases. The BECM 10 and PCM 14 control at least the battery temperature control device 20 and the DC-DC converter 4. The BECM 10 also functions as an SOC determination unit in each of the multiple battery modules. Specifically, the BECM 10 calculates the SOC in each of the multiple battery modules based on the detection results of the battery voltage sensor 12 and the battery current sensor 13, and determines the magnitude relationship with a predetermined standard, for example, 95%.

[0143] BECM10 and PCM14 are used when multiple battery modules have a temperature lower than the first temperature T1, and the set charging time t user Then, the order in which multiple battery modules are warmed up is determined so that the charge level of the battery module as a battery pack is maximized. Furthermore, BECM10 and PCM14 control the DC-DC converter 4 so that charging begins simultaneously with the start of the first warm-up and all at once, using the maximum current value set based on the temperature of each of the multiple battery modules. The first temperature T1 is the temperature at which the battery module has completed warming up, and the threshold temperature T determines whether or not the battery module needs to be warmed up. heat It is lower than that.

[0144] BECM10 and PCM14 are defined by a pre-set threshold temperature T heatIf there is a battery module with a lower battery temperature than the other battery module, the warm-up order is determined according to the individual battery temperatures of the multiple battery modules.

[0145] According to this embodiment, a larger total charge can be obtained with the same amount of heating compared to warming up multiple battery modules simultaneously.

[0146] Furthermore, in the configuration disclosed in Patent Document 1, charging is performed sequentially starting with the battery modules that have been warmed up and whose battery temperature has risen above a predetermined temperature. However, this method requires a long time to complete the charging of multiple battery modules. On the other hand, according to this embodiment, even if the battery temperature of some battery modules is low, charging is performed at the maximum current value that can be supplied, thus shortening the time required to charge multiple battery modules.

[0147] BECM10 and PCM14 refer to the set charging time t user Therefore, it is preferable to control the battery temperature control device 20 so that the battery modules with higher temperatures are warmed up first, in order to maximize the charge amount of the battery modules as a battery pack. By doing so, a larger total charge amount can be reliably obtained compared to warming up multiple battery modules simultaneously with the same amount of heating.

[0148] Furthermore, if there are battery modules whose battery temperature is above the first temperature T1, the BECM10 and PCM14 may control the battery temperature control device 20 to prioritize warming up the battery module with the highest temperature among the battery modules whose battery temperature is below the first temperature T1.

[0149] In this case as well, a larger total charge can be obtained with the same amount of heating than by warming up multiple battery modules simultaneously. Furthermore, when the battery temperature is above the first temperature T1, the effect of warming up to shorten the charging time (temperature control effect) is smaller for the high-temperature battery modules. For this reason, starting the warming up process from the low-temperature battery modules can shorten the total time required to charge multiple battery modules.

[0150] Furthermore, BECM10 performs a charge amount prediction calculation based at least on the initial temperature, initial SOC, and target charging time of multiple battery modules, and derives the warm-up order and warm-up completion temperature of the multiple battery modules.

[0151] Furthermore, when predicting the charge amount, BECM10 and PCM14 vary the warm-up completion temperature and calculate the final charge amount (final charge amount) for cases where the high-temperature battery module is warmed up first and for cases where the low-temperature battery module is warmed up first. BECM10 and PCM14 then each derive the warm-up completion temperature that maximizes the derived final charge amount, compare the maximum values ​​of each final charge amount, and determine the warm-up order for the battery module that maximizes the final charge amount. Finally, BECM10 and PCM14 control the battery temperature control device 20 to warm up the batteries according to the determined warm-up order.

[0152] This way, the user can set a target charging time t user The warm-up conditions for multiple battery modules can be appropriately and accurately set to maximize the charge amount. In other words, BECM10 and PCM14 can be set to the target charge time t user The warm-up sequence of multiple battery modules is determined to obtain the maximum charge amount, and the warm-up completion temperature is varied to warm up the multiple battery modules.

[0153] Furthermore, BECM10 and PCM14 prioritize warming up the battery module that was first warmed up until it reached its warm-up completion temperature. For example, when warming up the high-temperature battery module first, mod(H) is set to the warm-up completion temperature T. end1 After warming up to a certain temperature, the warm-up process mod(H) is stopped, and the warm-up process mod(L) is started, until the warm-up is complete at temperature T. end1 Warm it up until it reaches this point. Doing so reduces the total time required to warm up the battery module.

[0154] Furthermore, the charging control method for the secondary battery according to this embodiment comprises at least the following first to third steps.

[0155] In the first step, the initial battery temperature of each of the multiple battery modules is input (steps S4 and S6 in Figure 5, step S90 in Figure 8, and Figure 10).

[0156] In the second step, the warm-up sequence and the warm-up completion temperature of the multiple battery modules are derived based on the initial battery temperatures of each of the multiple battery modules received in the first step (steps S4-S7 in Figure 5, steps S92 and S93 in Figure 8, and Figure 10).

[0157] In the third step, based on the warm-up sequence and warm-up completion temperature of the multiple battery modules derived in the second step, the multiple battery modules are warmed up individually while simultaneously charging the multiple battery modules. (Steps S8 onwards in Figure 6A, Steps S31 onwards in Figure 6C, Steps S95 onwards in Figure 9A, Steps S105 onwards in Figure 9B). In this specification, individually warming up multiple battery modules means determining the warm-up sequence of the battery modules using the procedure shown in Figures 5 to 10, and warming up the multiple battery modules according to the determined warm-up sequence.

[0158] By doing this, a greater total charge can be obtained with the same amount of heating compared to warming up multiple battery modules simultaneously. Furthermore, the total time required to charge multiple battery modules can be reduced.

[0159] In the first step, the initial SOC and target charging time t of each of the multiple battery modules are determined. user Further input is accepted. In this case, it is preferable that in the second step, the charge amount of the multiple battery modules is predicted based at least on the parameters input in the first step and the respective thermal capacity and charging current maps of the multiple battery modules, and the warm-up completion temperature is extracted.

[0160] In this way, the warm-up conditions for multiple battery modules can be set appropriately and accurately, and the target charging time t can be set. user This allows for maximizing the amount of charge in that location.

[0161] The initial battery temperature of each of the multiple battery modules is a predetermined threshold temperature T heat If the above conditions are met, or if any of the battery modules have completed warming up, the third step does not involve warming up the battery modules. This eliminates unnecessary warming-up work and the energy used for warming up.

[0162] Furthermore, the charging control program according to this embodiment causes one or more CPUs provided in the BECM10 and / or PCM14 to execute the charging control method described above.

[0163] In this way, charging control of multiple battery modules can be performed simply and reliably. It is preferable that the program be stored in a memory unit (not shown) located inside or outside the vehicle 1. If the memory unit is located outside the vehicle 1, the program is read to the BECM10 and / or PCM14 via a communication unit (not shown).

[0164] (Embodiment 2) Figure 16 shows the differences between the battery charging control procedure according to Embodiment 2 and the battery charging control procedure according to Embodiment 1. Figure 17 shows the differences between the battery warm-up control procedure according to Embodiment 2 and the battery warm-up control procedure according to Embodiment 1. Figure 18 is a flowchart showing the procedure for predicting the charging time until the target SOC is reached.

[0165] Figure 19 shows the time-series change in the State of Charge (SOC) of battery modules A and B when the high-temperature module is warmed up first. In the curve showing the time-series change in SOC in Figure 19, the thick line represents the warm-up period.

[0166] Furthermore, for the sake of clarity, in Figure 16 and the subsequent drawings, the same reference numerals are used for parts that are the same as in Embodiment 1, and detailed explanations are omitted.

[0167] In Embodiment 1, as shown in Figures 5, 8, and 10, the user sets a target charging time t user Set in advance, target charging time t user This describes a configuration in which the maximum total charge amount can be obtained when charging multiple battery modules within a certain timeframe.

[0168] On the other hand, in this embodiment, the user may pre-set a target SOC (target SOC) in the setting conditions (INPUT2) shown in Figure 10. In this case, the charging time until the target SOC is reached can be minimized.

[0169] In this case, as shown in Figure 16, steps S5 and S7 in Figure 5 are changed to steps S5A and S7A, respectively. In step S5A, the warm-up completion temperature T allows for a shorter charging time relative to the user-set target SOC. end1 The following is calculated. In step S7A, the warm-up completion temperature T is calculated so that the charging time can be shortened for the user-set target SOC. end2 This is calculated.

[0170] Furthermore, as shown in Figure 17, steps S92 to S94 in Figure 8 are changed to steps S92A to S94A, respectively. In step S92A, the BECM10 performs a prediction calculation of the charging time based on the various parameters read in step S90 and the heat capacities mod(A) and mod(B). This calculation is performed by varying the warm-up completion temperature within a predetermined temperature range in a pattern where warm-up starts from mod(H). Also, as a result of the prediction calculation, the minimum value t of the charging time is obtained. min(H) This is extracted. Furthermore, the warm-up completion temperature T mod(H) when the charging time is minimized is also extracted. end(H) This is extracted and stored in the aforementioned memory unit.

[0171] In step S93A, the BECM10 performs a prediction calculation of the charging time based on the various parameters read in step S90, the charging current map, and the thermal capacities mod(A) and mod(B). This calculation is performed by varying the warm-up completion temperature within a predetermined temperature range, starting with a warm-up from mod(L). As a result of the prediction calculation, the minimum value of the charging time t is determined. min(L) This is extracted. Furthermore, the warm-up completion temperature T mod(L) when the charging time is minimized is also extracted. end(L) This is extracted and stored in the aforementioned memory unit.

[0172] In step S94A, t min(H) ga t min(L) Determine whether it is smaller than or equal to [a certain value]. If the result of the determination in step S94A is positive, proceed to subprocess G; otherwise, proceed to subprocess H.

[0173] Furthermore, once the initial input conditions and charging settings are entered, BECM10 calculates the time-series change of SOC according to the process shown in Figure 18 (process B shown in Figure 10).

[0174] First, the charging current is calculated based on the charging current map, specifically the initial SOC and the initial battery temperature (step S140). Next, the amount of charge ΔSOC from the start of charging until Δt seconds have elapsed is calculated (step S141), and then the battery temperature Δt seconds after the start of charging is calculated based on the amount of heating and the heat capacity of the battery (step S142).

[0175] Next, i=1 is set (step S143), and the charging current is calculated based on the SOC at time ti (hereinafter referred to as SOC(i)) and the battery temperature (step S144). Next, the amount of charge ΔSOC from time ti to Δt seconds later is calculated (step S145), and the battery temperature Δt seconds after time ti is calculated based on the amount of heating and the heat capacity of the battery (step S146). Next, it is determined whether the SOC at time (ti+Δt) has reached the target SOC (step S147). If the result of the determination in step S147 is negative, that is, if the SOC at time (ti+Δt) has not reached the target SOC, i=i+1 is set (step S149). The process returns to step S144, and the series of processes from step S144 to step S147 are repeated until the result of the determination in step S147 becomes positive.

[0176] If the judgment result in step S147 is positive, the time t at which the target SOC is reached is calculated (step S148), and the time series change of SOC up to time t is calculated.

[0177] Similar to process A, process B is executed for each combination of warm-up sequence and warm-up completion temperature. As a result of execution, when the warm-up completion temperature and warm-up sequence are changed, the time-series change of SOC until the target SOC is reached, i.e., a set of SOC time charts, is obtained.

[0178] As described above, the secondary battery charging control device 40 according to this embodiment differs from the configuration shown in Embodiment 1 in the following respects.

[0179] BECM10 performs a charging time prediction calculation based at least on the initial temperature, initial SOC, and target SOC of multiple battery modules, and derives the warm-up order and warm-up completion temperature of the multiple battery modules.

[0180] Furthermore, when predicting the charging time, BECM10 and PCM14 vary the warm-up completion temperature and calculate the final charging time (required charging time) for cases where the high-temperature battery module is warmed up first and for cases where the low-temperature battery module is warmed up first. BECM10 and PCM14 then each derive the warm-up completion temperature that results in the shortest required charging time, compare the minimum required charging times, and determine the warm-up order of the battery modules that results in the shortest required charging time. Finally, BECM10 and PCM14 control the battery temperature control device 20 to warm up the modules in the determined warm-up order.

[0181] In this way, the warm-up conditions for multiple battery modules can be appropriately and accurately set to minimize the charging time at the user-defined target SOC. In other words, BECM10 and PCM14 determine the warm-up order of multiple battery modules and warm up the multiple battery modules by changing the warm-up completion temperature in order to obtain the minimum charging time at the target SOC.

[0182] Furthermore, according to this embodiment, in a battery pack composed of multiple battery modules, the charging process can be completed in a shorter charging time to obtain the same amount of charge. For example, in the comparative example shown in Figure 18, the batteries are warmed up in the order mod(H) → mod(L), and charging is started only after the battery temperature after warming up has reached a predetermined temperature or higher. This is the same method as shown in Patent Document 1. In this case, t2 is the time from when the warming and charging of mod(H) is started until mod(L), which was warmed up later, reaches the target SOC, which is SOC(T). Time t2 is the total charging time of mod(H) and mod(L) in the comparative example.

[0183] On the other hand, according to this embodiment, similar to Embodiment 1, the warm-up is performed in the order mod(H) → mod(L), and the charging of mod(H) is started at the same time as the warm-up and charging of mod(H). As a result, the total charging time t2 until mod(H) and mod(L) reach SOC(T) in this embodiment can be made shorter than the aforementioned time t1.

[0184] Furthermore, the charging control method for the secondary battery according to this embodiment differs from the charging control method shown in Embodiment 1 in the following respects.

[0185] In the first step, the initial SOC and target SOC of each of the multiple battery modules are further input. In this case, it is preferable that in the second step, the charging time of the multiple battery modules is predicted based on the parameters input in the first step and at least the thermal capacity and charging current map of each of the multiple battery modules, and the warm-up completion temperature is extracted.

[0186] By doing so, the warm-up conditions for multiple battery modules can be set appropriately and accurately, minimizing the charging time at the target State of Charge (SOC).

[0187] Furthermore, similar to that shown in Embodiment 1, the charge control program according to this embodiment also causes one or more CPUs provided in the BECM10 and / or PCM14 to execute the charge control method shown in this embodiment. In this way, the charge control of multiple battery modules can be performed simply and reliably.

[0188] (Other embodiments) Target charging time t userThe target SOC can be said to be a requirement for charging multiple battery modules as a battery pack. Therefore, if there are battery modules among the multiple battery modules that are at a temperature lower than the first temperature T1, the BECM10 and PCM14 disclosed in this specification perform the following control. First, under predetermined setting conditions, if there are multiple battery modules among the multiple battery modules that are at a temperature lower than the first temperature T1, which is the warm-up completion temperature, the warm-up order of the multiple battery modules is determined under predetermined setting conditions to maximize the requirement for charging as a battery pack. At the same time, the DC-DC converter 4 is controlled to charge the multiple battery modules simultaneously and at the same time as the start of the first warm-up with the maximum current value set based on the temperature of each of the multiple battery modules. Note that the first temperature T1 is the threshold temperature T used to determine whether warm-up is necessary. heat It is lower than that.

[0189] In this way, the charging requirements for multiple battery modules can be maximized according to user settings, regardless of the individual battery temperatures. heat By setting it lower than this, the warm-up sequence of the battery modules can be easily determined.

[0190] The setting condition is the target charging time (=t user If the charging requirement is to maximize the charge level of the battery pack, the BECM10 and PCM14 control the battery temperature control device 20 to prioritize warming up the battery modules on the side with the higher temperature.

[0191] Furthermore, if there are battery modules whose battery temperature is above the first temperature T1, the BECM10 and PCM14 may control the battery temperature control device 20 to prioritize warming up the battery module with the highest temperature among the battery modules whose battery temperature is below the first temperature T1.

[0192] Furthermore, BECM10 and PCM14 refer to the target charging time t userWhen this setting is configured, the warm-up completion temperatures of multiple battery modules are changed to maximize the charge amount of the battery pack as a whole.

[0193] By doing this, a greater total charge can be obtained with the same amount of heating compared to warming up multiple battery modules simultaneously.

[0194] Furthermore, if the setting condition is a target SOC and the charge requirement is to minimize the charging time of the battery pack until the target SOC is reached, the BECM10 and PCM14 control the battery temperature control device 20 to prioritize warming up the battery module with the higher temperature.

[0195] Furthermore, if there are battery modules whose battery temperature is above the first temperature T1, the BECM10 and PCM14 may control the battery temperature control device 20 to prioritize warming up the battery module with the highest temperature among the battery modules whose battery temperature is below the first temperature T1.

[0196] Furthermore, once a target SOC is set, BECM10 and PCM14 change the warm-up completion temperature of multiple battery modules to minimize the charging time in the battery pack.

[0197] By doing this, multiple battery modules can be charged in a shorter charging time than if multiple battery modules were warmed up simultaneously with the same amount of heat.

[0198] Furthermore, the BECM10 disclosed in this specification can be said to perform a predictive calculation of numerical values ​​related to the charging requirements of multiple battery modules, i.e., the required values, based on multiple parameters relating to multiple battery modules, and derive the warm-up sequence and warm-up completion temperature of the multiple battery modules.

[0199] Furthermore, when predicting the required values, BECM10 varies the warm-up completion temperature and calculates the required values ​​for charging when warming up from the high-temperature battery module and when warming up from the low-temperature battery module. In each case, BECM10 derives the warm-up completion temperature corresponding to the derived required value. BECM10 and PCM14 compare the derived required values ​​and determine the warm-up order of the battery modules to maximize or minimize the required value. BECM10 and PCM14 also control the battery temperature control device 20 to warm up according to the determined warm-up order.

[0200] Target charging time t user If the setting is configured and the charging request is to maximize the charge amount, the BECM10 and PCM14 compare the derived final charge amounts and determine the warm-up sequence of the battery modules to maximize or minimize the final charge amount. The BECM10 and PCM14 also control the battery temperature control device 20 to warm up according to the determined warm-up sequence.

[0201] Furthermore, BECM10 and PCM14 control the battery temperature control device 20 so that the battery module on the side with the higher temperature for the final charge amount is warmed up first.

[0202] Furthermore, if a target SOC is set and the charging requirement is to minimize the charging time until the target SOC is reached, the BECM10 and PCM14 compare the derived charging times and determine the warm-up sequence of the battery modules to minimize the charging time. The BECM10 and PCM14 also control the battery temperature control device 20 to warm up according to the determined warm-up sequence.

[0203] Furthermore, BECM10 and PCM14 control the battery temperature control device 20 to warm up the battery module starting from the side with the lower temperature, which shortens the charging time.

[0204] In other words, BECM10 and PCM14 determine the warm-up sequence of multiple battery modules and warm up the multiple battery modules by varying the warm-up completion temperature in order to maximize the charging requirements of the battery pack.

[0205] In this way, the warm-up conditions for multiple battery modules can be appropriately and accurately set to maximize the user-defined charging requirements for the battery pack.

[0206] Furthermore, the secondary battery charging control method disclosed in this specification comprises at least the following first to third steps using a charging control device 40.

[0207] In the first step, the system accepts input for multiple parameters related to multiple battery modules.

[0208] In the second step, the warm-up sequence and the warm-up completion temperature for the multiple battery modules are derived based on the parameters of each battery module received in the first step.

[0209] In the third step, based on the warm-up sequence and warm-up completion temperature of the multiple battery modules derived in the second step, the multiple battery modules are warmed up individually while simultaneously being charged.

[0210] The parameters in the first step include the initial temperature, initial SOC, heating amount, thermal capacity, charging current map, and user-defined settings for each of the multiple battery modules.

[0211] In this way, when charging multiple secondary batteries in parallel, the charging requirements of the battery pack can be maximized according to the charging settings, regardless of the temperature of each battery.

[0212] Setting conditions target charging time t userTherefore, if the charging requirement is to maximize the final charge amount, in the second step, the final charge amount is calculated for cases where the warm-up completion temperature is varied and the warm-up is performed from the high-temperature battery module and from the low-temperature battery module, and these final charge amounts are compared. In the third step, the warm-up is performed from the battery module with the temperature that will result in the larger final charge amount. Alternatively, in the third step, based on the comparison of the final charge amounts, multiple battery modules are warmed individually according to a warm-up order determined to maximize the final charge amount, while multiple battery modules are charged simultaneously.

[0213] By doing this, a greater total charge can be obtained with the same amount of heating compared to warming up multiple battery modules simultaneously.

[0214] Furthermore, if the setting condition is a target SOC and the charging requirement is to minimize the charging time, in the second step, the charging time is calculated for both warming up from the high-temperature battery module and warming up from the low-temperature battery module, with the warm-up completion temperature being varied, and the respective charging times are compared. In the third step, the battery modules are warmed up starting from the temperature side that results in the shorter charging time. Alternatively, in the third step, multiple battery modules are warmed up individually according to a warm-up sequence determined to minimize the charging time based on the comparison of charging times, while multiple battery modules are charged simultaneously.

[0215] By doing this, the total time required to charge multiple battery modules can be shortened compared to warming up multiple battery modules simultaneously with the same amount of heat.

[0216] The initial battery temperature of each of the multiple battery modules determines the threshold temperature T required to determine whether or not the battery modules need to be warmed up. heat If the above conditions are met, or if any of the battery modules have completed warming up, the third step does not involve warming up the battery modules. This eliminates the need for unnecessary warming-up work.

[0217] Furthermore, the charging control program disclosed in this specification causes one or more CPUs provided in the BECM10 and / or PCM14 to execute the charging control method described above.

[0218] Furthermore, the greater the amount of heat applied, the faster the battery module heats up. On the other hand, the heating rate is almost constant regardless of the battery temperature range of the battery module. Therefore, if the battery temperatures differ among multiple battery modules, the heating rate will hardly change, only the initial battery temperatures will differ.

[0219] Furthermore, the smaller the amount of heating, or in other words, the lower the heating rate, the better the maximization of the requirements for charging the battery pack can be satisfied compared to warming up multiple battery modules simultaneously with the same amount of heating. However, even if the amount of heating is large, the charging speed will increase compared to warming up multiple battery modules simultaneously, thus achieving the effects of this disclosure. [Industrial applicability]

[0220] The secondary battery charging control device of this disclosure is useful because, when charging a battery pack composed of multiple secondary batteries, it can efficiently warm up and charge the entire battery pack according to the charging settings. [Explanation of Symbols]

[0221] 1 vehicle 2A~2B Battery Module (Battery) 3 battery cells 4, 4A, 4B DC-DC converter (charging current regulator) 5 Inverter 6 motors 7A, 7B circuit selector switch 10 BECM (Control Device) 11. Battery temperature sensor 12 Battery voltage sensor 13. Battery current sensor 14. PCM (Control Device) 20 Battery temperature control device (Battery temperature adjustment device) 21 Heater 22 Fluid pump 23 Temperature control plate 24A First main pipe 24B Second main pipe 25A - 25D Branch pipes 26A - 26D Flow path switching valves 30 Charging equipment 31 Rapid charger 40 Charging control device

Claims

1. A charging control device for secondary batteries that make up a battery pack, The multiple secondary batteries included in the aforementioned battery pack are connected in parallel during operation. The charging control device is Each of the multiple secondary batteries is provided with a battery temperature detection means for detecting the temperature of the secondary battery, A battery temperature control device that can switch the secondary battery to be warmed up, A charging current adjustment device is provided for each of the multiple secondary batteries, and is capable of adjusting the charging current to decrease as the temperature of the secondary battery decreases. The system includes a control device that controls the battery temperature adjustment device and the charging current adjustment device, respectively. The control device is A secondary battery charging control device characterized in that, when there are multiple secondary batteries among the multiple secondary batteries whose temperature is lower than a first temperature which is the warm-up completion temperature, it determines the order in which to warm up the multiple secondary batteries in order to maximize the demand for charging as a battery pack under predetermined setting conditions, and controls the charging current adjustment device to perform charging simultaneously and at the same time as the start of the first warm-up with a maximum current value set based on each temperature.

2. In the charging control device for a secondary battery according to claim 1, The charging control device further comprises an SOC determination unit that determines the SOC in each of the plurality of secondary batteries, The charging current adjustment device is capable of adjusting the charging current according to the temperature and the state of temperature (SOC), and is characterized in that it can adjust the charging current to decrease as the SOC of the secondary battery increases.

3. In the charging control device for a secondary battery according to claim 1, If the setting condition is the target charging time, and the request regarding charging is to maximize the charge amount of the battery pack, The charging control device for a secondary battery is characterized in that the control device controls the battery temperature control device so as to prioritize warming up the secondary battery on the side with the higher temperature.

4. In the charging control device for a secondary battery according to claim 3, If there is a secondary battery whose temperature is equal to or higher than the first temperature, A secondary battery charging control device characterized in that the control device controls the battery temperature adjustment device so that it prioritizes warming up the secondary battery with the highest temperature among the secondary batteries whose temperature is lower than the first temperature.

5. In the charging control device for a secondary battery according to claim 1, If the setting condition is the target charging time, and the request regarding charging is to maximize the amount of charge of the battery pack, A secondary battery charging control device characterized in that the control device changes the warm-up completion temperature of the secondary battery so as to maximize the amount of charge as a battery pack at the target charging time.

6. In the charging control device for a secondary battery according to claim 1, If the setting condition is the target SOC, and the request regarding charging is to minimize the charging time of the battery pack until the target SOC is reached, The charging control device for a secondary battery is characterized in that the control device controls the battery temperature control device so as to prioritize warming up the secondary battery on the side with the higher temperature.

7. In the charging control device for a secondary battery according to claim 6, If there is a secondary battery whose temperature is equal to or higher than the first temperature, A secondary battery charging control device characterized in that the control device controls the battery temperature adjustment device so that it prioritizes warming up the secondary battery with the highest temperature among the secondary batteries whose temperature is lower than the first temperature.

8. In the charging control device for a secondary battery according to claim 1, If the setting condition is the target SOC, and the request regarding charging is to minimize the charging time of the battery pack until the target SOC is reached, The control device is characterized by changing the warm-up completion temperature of the secondary battery in order to minimize the charging time in the battery pack.

9. In the charging control device for a secondary battery according to claim 1, The charging control device for a secondary battery is characterized in that the control device performs a predictive calculation of a value related to the request based on a plurality of parameters relating to the plurality of secondary batteries, and derives the warm-up sequence and the warm-up completion temperature of the plurality of secondary batteries.

10. In the charging control device for a secondary battery according to claim 9, The multiple parameters include at least the initial temperature, initial SOC, heating amount, and target charging time of the multiple secondary batteries. The control device is The warm-up completion temperature of the secondary battery is varied, and the final charge amount is calculated for cases where the secondary battery on the high-temperature side is warmed up and cases where the secondary battery on the low-temperature side is warmed up, and these final charge amounts are compared. A secondary battery charging control device characterized by determining the warm-up sequence of the secondary battery that will result in the largest final charge, and controlling the battery temperature control device to warm up the battery in accordance with the warm-up sequence.

11. In the charging control device for a secondary battery according to claim 9, The multiple parameters include at least the initial temperature, initial SOC, heating amount, and target SOC of the multiple secondary batteries. The control device is The warm-up completion temperature of the secondary battery is varied, and the charging time required is calculated for cases where the secondary battery on the high-temperature side is warmed up first and for cases where the secondary battery on the low-temperature side is warmed up first, and these charging times are compared. A secondary battery charging control device characterized by determining the warm-up sequence of the secondary battery that results in the shortest charging time, and controlling the battery temperature control device to warm up the battery in the order described above.

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