Storage battery temperature adjusting system

Abstract

The purpose of the present invention is to suppress storage battery output limitation caused by local lowering of the temperature of a storage battery or storage battery deterioration caused by local increasing of the temperature of the storage battery. A battery temperature control system (1) is provided with: a battery (3); a cooling device (4) that cools the battery (3); a heating device (5) that heats the battery (3); a battery ECU (6) that acquires the temperature of the battery; and a temperature control unit (7) that controls the cooling device (4) and the heating device (5). The temperature adjustment control unit (7) is configured so as to be capable of switching between a cooling state in which the cooling device (4) is in an operating state and the heating device (5) is in a non-operating state, a heating state in which the cooling device (4) is in a non-operating state and the heating device (5) is in an operating state, and a stopped state in which the cooling device is in a non-operating state and the heating device is in a non-operating state. The temperature control unit switches between the cooling state and the heating state at least once when the temperature of the battery approaches the target temperature.

Description

Technical Field

[0001] The invention relates to a battery temperature regulating system. Background Art

[0002] In recent years, efforts to achieve a low-carbon or decarbonized society have been actively underway, and research and development related to electrification technologies are being conducted to reduce CO2 emissions and improve energy efficiency in vehicles.

[0003] Batteries play an important role in electrification technology. To prevent battery output limitation and degradation, battery temperature control is performed to maintain the battery temperature within a desired temperature range.

[0004] For example, Patent Document 1 discloses a system that estimates the maximum temperature inside a battery cell in a battery module composed of multiple battery cells, and controls the charge and discharge current of the battery module or the cooling of the battery module so that the estimated maximum temperature does not exceed an upper limit temperature during charging and discharging of the battery module.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. 2019 / 244489 Summary of the Invention

[0008] Problems to be solved by the invention

[0009] However, when cooling the battery module to keep the maximum temperature below the upper limit, the minimum temperature of the battery module may become too low, limiting the battery output. In particular, the electrode bodies of recent high-capacity laminated cells have large areas, and the temperature distribution within the cell tends to increase during cooling, heating, and when high current is applied.

[0010] The present invention provides a battery temperature regulating system, which can eliminate the temperature difference inside the battery and make the battery temperature close to the target temperature.

[0011] Means for solving problems

[0012] The present invention is a battery temperature control system, which comprises:

[0013] batteries;

[0014] a cooling unit for cooling the battery;

[0015] a heating unit that heats the battery;

[0016] a temperature acquiring unit configured to acquire the temperature of the battery; and

[0017] a temperature control unit that controls the cooling unit and the heating unit,

[0018] The temperature control unit can switch between cooling, heating and stopping states.

[0019] In the cooling state, the cooling unit is in an operating state and the heating unit is in a non-operating state.

[0020] In the heating state, the cooling unit is in a non-operating state and the heating unit is in an operating state.

[0021] In the stopped state, the cooling unit is in a non-operating state and the heating unit is in a non-operating state.

[0022] When the temperature of the battery is brought close to a target temperature, the cooling state and the heating state are switched at least once.

[0023] Effects of the Invention

[0024] According to the present invention, the temperature difference inside the battery can be eliminated while bringing the battery temperature close to the target temperature, thereby preventing the battery output from being restricted due to a localized decrease in temperature or the battery from being deteriorated due to a localized increase in temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a block diagram of a battery temperature control system 1 according to one embodiment of the present invention.

[0026] Figure 2 It is a schematic diagram for explaining the temperature inside the battery 3 .

[0027] Figure 3 Graphs showing (a) the temperature inside the battery and (b) the allowable output of the battery in a cooling mode for cooling the battery in a conventional battery temperature control system.

[0028] Figure 4 Graphs showing (a) the temperature inside the battery, (b) the water temperature, and (c) the allowable output of the battery in a cooling mode for cooling the battery 3 of the battery temperature control system 1 according to the present embodiment.

[0029] Figure 5 Graphs showing the temperature inside the battery, the battery's allowable output, and the water temperature in each of the three cooling modes used by the battery temperature control system 1 to cool the battery 3, more specifically, (a) cooling priority mode, (b) normal cooling mode, and (c) output priority mode.

[0030] Figure 6 It is used to execute Figure 5 Flowchart (1) illustrating the steps of the cooling mode.

[0031] Figure 7 It is used to execute Figure 5 Flowchart (part 2) illustrating the steps of the cooling mode.

[0032] Figure 8 This is a graph showing the temperature inside the battery in a heating mode for heating the battery in a conventional battery temperature control system.

[0033] Figure 9 Graphs showing (a) the temperature inside the battery and (b) the water temperature in the heating mode for heating the battery 3 in the battery temperature control system 1 according to the present embodiment.

[0034] Figure 10 Graphs showing the temperature inside the battery and the water temperature in heating modes in which the battery temperature control system 1 heats the battery 3 , more specifically, in two modes: (a) the heating priority mode and (b) the active protection mode.

[0035] Figure 11 It is used to execute Figure 10 A flow chart illustrating the steps of the heating mode.

[0036] Description of Reference Numerals

[0037] 1 Battery temperature control system

[0038] 2 Control Unit

[0039] 3. Battery

[0040] 4 Cooling equipment (cooling unit)

[0041] 5. Heating equipment (heating unit)

[0042] 6 Battery ECU (temperature acquisition unit, output control unit)

[0043] 7 Temperature control unit

[0044] 8 EWP

[0045] 9 User Interface

[0046] 11 Water Jacket

[0047] 12 Temperature control circuit

[0048] 31 Lower battery area

[0049] 32 Upper battery area DETAILED DESCRIPTION

[0050] Hereinafter, a battery temperature control system according to an embodiment of the present invention will be described with reference to the drawings.

[0051] Figure 1 This is a diagram showing a block diagram of a battery temperature control system 1 in one embodiment of the present invention. The battery temperature control system 1 includes a control unit 2, a battery 3, a cooling device 4, a heating device 5, an EWP (Electric Water Pump) 8, and a user interface 9. The battery temperature control system 1 is a system installed in, for example, an electrically powered vehicle and controls the temperature of the battery serving as a power source. The battery 3, the cooling device 4, the heating device 5, and the EWP 8 are arranged in a temperature control circuit 12 through which refrigerant circulates. Inside the battery 3, a water jacket 11 (see FIG. 1 ) connected to the temperature control circuit 12 is provided. Figure 2 ) is configured to be in direct or indirect contact with one surface of the battery 3 and capable of heat exchange with the battery 3.

[0052] The control unit 2 is, for example, a computer that centrally controls the entire battery temperature control system 1. It includes a processor that performs various calculations, a storage unit with a non-transitory storage medium for storing various information, and an input / output unit that controls the input and output of data within and outside the control unit 2 (none of which are shown). The control unit 2 includes a battery ECU (Electronic Control Unit) 6 and a temperature control unit 7.

[0053] Battery 3 includes multiple cells and supplies power to drive the vehicle. The cells are, for example, laminated cells made of solid-state batteries. Laminated cells have a positive electrode connected to a positive tab, a negative electrode connected to a negative tab, a solid electrolyte disposed between the positive and negative electrodes, and a laminated film containing them. Charging and discharging occur through the transfer of lithium ions between the positive and negative electrodes via the solid electrolyte. Cooling device 4 functions as a cooling unit that cools battery 3 and prevents its temperature from rising. Heating device 5 functions as a heating unit that heats battery 3 and prevents its output from being restricted. EWP 8 is a so-called electric water pump, a device that circulates refrigerant while flowing around battery 3. User interface 9 is an interface device including switches, buttons, a touch panel, and the like, which allow a user (e.g., the driver of the vehicle) to input operations for battery temperature control system 1.

[0054] As described later, the battery ECU 6 of the control unit 2 functions as a temperature acquisition unit that acquires the temperature of the battery 3. Furthermore, the battery ECU 6 also functions as an output control unit that controls the output of the battery 3. The temperature control unit 7 receives temperature information of the battery 3 from the battery ECU 6 and controls the cooling device 4 and heating device 5 to control the temperature of the battery 3.

[0055] Figure 2 This is a schematic diagram illustrating the internal temperature of battery 3, specifically, the temperature distribution of each cell constituting battery 3. In this embodiment, water jacket 11 connected to temperature control circuit 12 is in indirect contact with the lower surface of battery 3 (cell) via heat transfer element 13.

[0056] Assuming that the battery 3 is being cooled, as refrigerant circulates through the water jacket 11, the temperature of the lower battery region 31 (cell lower region) near the water jacket 11 tends to drop, while the temperature of the upper battery region 32 (cell upper region) farther from the water jacket 11 tends to decrease, resulting in a temperature distribution within the battery. Based on this perspective, the battery ECU 6 obtains the temperature of at least one side of the battery 3 (the lower surface in this figure) and the temperature of the side opposite to that side (the upper surface in this figure), and performs temperature control taking into account the temperature distribution within the battery.

[0057] Furthermore, the battery ECU 6 determines the allowable power by referring to the minimum temperature of the battery 3 during normal use. Therefore, as temperature distribution develops within the battery, the available power is more restricted, making it more difficult to fully utilize the battery performance.

[0058] When cooling battery 3 so that its maximum temperature does not exceed the upper temperature limit, the minimum temperature of battery 3 may become too low, limiting the output of battery 3. In particular, the recently introduced high-capacity laminated cells have large electrode bodies, and the temperature distribution within the battery tends to increase during cooling, heating, and when high currents are applied. Furthermore, in the case of all-solid-state batteries, due to their high upper temperature limit, the temperature distribution within the battery is more likely to increase. To effectively deplete the battery, it is necessary to reduce this temperature distribution.

[0059] Therefore, in this embodiment, the temperature control unit 7 is capable of switching between a cooling state in which the cooling device 4 is in operation and the heating device 5 is inoperative, a heating state in which the cooling device 4 is inoperative and the heating device 5 is in operation, and a stopped state in which the cooling device 4 is inoperative and the heating device 5 is inoperative. Furthermore, the temperature control unit 7 switches between the cooling state and the heating state at least once, and preferably multiple times, to bring the temperature of the battery 3 closer to the target temperature. The specific control method is described below.

[0060] Figure 3 Graphs showing (a) the temperature inside the battery and (b) the allowable output in a cooling mode for cooling the battery in a conventional battery temperature control system. Figure 3(a) shows the temporal changes in the water temperature (refrigerant temperature), the minimum battery temperature Tmin, and the maximum battery temperature Tmax relative to the target temperature of the battery 3, which serves as a constant control target. The maximum battery temperature Tmax, located near the upper battery region 32, remains above the target temperature over time. Meanwhile, the minimum battery temperature Tmin, located near the lower battery region 31, falls below the target temperature over time.

[0061] When the battery ECU 6 obtains the minimum temperature Tmin and the maximum temperature Tmax of the battery 3, it determines the allowable power of the battery 3 with reference to the minimum temperature Tmin. Figure 3 As shown in (b), when the minimum temperature Tmin in the battery is lower than the target temperature, the battery ECU 6 limits the allowable output of the battery 3 , thereby limiting the available electric power.

[0062] on the other hand, Figure 4 Graphs showing (a) the battery internal temperature, (b) the water temperature, and (c) the allowable output in the cooling mode for cooling the battery 3 of the battery temperature control system 1 according to the present embodiment.

[0063] The battery ECU 6 obtains the lower battery temperature Td of the lower battery region 31 and the upper battery temperature Tu of the upper battery region 32, and calculates the maximum battery temperature Tmax and the minimum battery temperature Tmin. The method for calculating the maximum battery temperature Tmax and the minimum battery temperature Tmin is not particularly limited. The maximum battery temperature Tmax and the minimum battery temperature Tmin may be calculated by taking the highest temperature among the temperatures measured at multiple points and setting the minimum battery temperature Tmin as the lowest temperature. Alternatively, the maximum battery temperature Tmax and the minimum battery temperature Tmin may be calculated by taking the average of the temperatures at multiple points on the high-temperature side and the average of the temperatures at multiple points on the low-temperature side. Alternatively, the calculation may be performed using a predetermined formula based on the upper and lower battery temperatures.

[0064] The temperature control unit 7 refers to the minimum temperature Tmin and the maximum temperature Tmax of the battery 3 and switches the state among the cooling state, the heating state, and the stop state as described above.

[0065] When cooling the battery 3, the temperature control unit 7 selects a cooling state in which the cooling device 4 is in operation and the heating device 5 is in non-operation. In the cooling state, the battery lower temperature Td (the lowest temperature in the battery Tmin) and the battery upper temperature Tu (the highest temperature in the battery Tmax) decrease. Figure 4As shown in (a) of FIG. 4 , when the battery lower temperature Td (the battery internal minimum temperature Tmin) is lower than the target temperature ( P1 ), the battery ECU 6 limits the allowable output of the battery 3 ( P2 ) as shown in (c) of FIG. 4 .

[0066] When a predetermined time has passed as the battery upper temperature Tu (maximum temperature Tmax in the battery) decreases, the temperature control unit 7 selects a heating state in which the cooling device 4 is inoperative and the heating device 5 is inoperative. Figure 4 As shown in (b), the water temperature begins to rise (P3). As the battery lower temperature Td in the battery lower region 31 near the water jacket 11 rises, the battery internal minimum temperature Tmin begins to rise (P4). When the battery lower temperature Td (battery internal minimum temperature Tmin) exceeds the target temperature (P5), the battery ECU 6 removes the restriction on the allowable output of the battery 3 (P6).

[0067] When the predetermined time has passed in the heating state, the battery lower temperature Td significantly exceeds the target temperature (P7). Then, the temperature control unit 7 switches to the cooling state in which the cooling device 4 is in the operating state and the heating device 5 is in the non-operating state. Figure 4 As shown in (b), the water temperature begins to drop (P8), and the battery lower temperature Td drops. When the battery lower temperature Td (the lowest temperature in the battery Tmin) is lower than the target temperature (P9), as shown in (b), the water temperature begins to drop (P8), and the battery lower temperature Td drops. Figure 4 As shown in (c), the battery ECU 6 limits the allowable output of the battery 3 (P10).

[0068] In this way, in an environment where the output of battery 3 is controlled based on the minimum temperature Tmin inside battery 3, by eliminating temperature differences inside battery 3 and bringing the temperature of battery 3 closer to the target temperature, it is possible to prevent the output of battery 3 from being restricted due to a local decrease in the temperature of battery 3.

[0069] Figure 5 Graphs showing the temperature inside the battery, the allowable output, and the water temperature in each of the three cooling modes used by the battery temperature control system 1 to cool the battery 3, more specifically, (a) cooling priority mode, (b) normal cooling mode, and (c) output priority mode.

[0070] exist Figure 5 In the cooling priority mode (a), switching from the cooling state to the heating state is performed at the following timing, for example.

[0071] When the operating time of the cooling device 4 exceeds the predetermined time

[0072] The time when the allowable output of the battery 3 reaches a predetermined output (or less)

[0073] The time when the temperature difference ΔT (ΔT = Td - Tu, the same applies hereinafter) obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td becomes less than or equal to the predetermined cooling allowable temperature difference T1 (ΔT ≤ T1)

[0074] In addition, switching from the heating state to the cooling state is performed, for example, at the following timing.

[0075] The moment when the temperature difference ΔT becomes zero (ΔT = 0)

[0076] This mode allows the maximum battery temperature Tmax to reach the target temperature in a short period of time. This allows for pre-cooling with a focus on rapid charging. Meanwhile, the output limit is increased until the maximum battery temperature Tmax reaches the target temperature.

[0077] exist Figure 5 In the normal cooling mode (b), switching from the cooling state to the heating state is performed at the following timing, for example.

[0078] When the operating time of the cooling device 4 exceeds the predetermined time

[0079] The time when the output is allowed to reach the predetermined specified output (or less)

[0080] The moment when the temperature difference ΔT becomes less than the specified allowable temperature difference T1 during cooling (ΔT ≤ T1)

[0081] In addition, switching from the heating state to the cooling state is performed, for example, at the following timing.

[0082] When the operating time of the heating device 5 has exceeded the prescribed time

[0083] The moment when the temperature difference ΔT is greater than the specified allowable temperature difference T2 during heating (ΔT>T2)

[0084] According to this mode, the maximum temperature Tmax in the battery reaches the target temperature within an appropriate time. Before reaching the target temperature, the output limit amount is limited to a certain extent.

[0085] exist Figure 5 In the output priority mode (c), switching from the cooling state to the heating state is performed, for example, at the following timing.

[0086] The moment when the temperature difference ΔT becomes less than the specified allowable temperature difference T1 during cooling (ΔT ≤ T1)

[0087] In addition, switching from the heating state to the cooling state is performed, for example, at the following timing.

[0088] The moment when the temperature difference ΔT becomes zero (ΔT = 0)

[0089] This mode can minimize the area where the output of battery 3 is limited, and can be applied to situations where cooling is required while ensuring a constant output, such as during normal driving. The time until the maximum temperature Tmax in the battery reaches the target temperature is prolonged.

[0090] In this embodiment, the battery ECU 6 acquires the temperatures of multiple locations within the battery 3 to obtain the minimum and maximum battery temperatures Tmin. Furthermore, the temperature control unit 7 can switch between the cooling and heating modes based on the temperature difference ΔT between the high-side temperature (maximum battery temperature Tmax) and the low-side temperature (minimum battery temperature Tmin). This prevents the temperature difference between the high-side and low-side temperatures of the battery 3 from increasing beyond a predetermined value.

[0091] Furthermore, the switching between the cooling state and the heating state by the temperature control unit 7 may also be based on the operating time of the cooling device 4 or the heating device 5. This prevents the temperature difference between the high-temperature side and the low-temperature side of the battery 3 from increasing beyond a predetermined value, and facilitates control.

[0092] Furthermore, the temperature control unit 7 is configured to regulate the temperature of the battery 3 in a plurality of modes having different switching conditions between the cooling state and the heating state. The plurality of modes can be set, for example, based on user requests input through the user interface 9. This allows the temperature regulation of the battery 3 to reflect the user's request.

[0093] Figure 6 It is used to execute Figure 5 Flowchart (Part 1) of the cooling mode steps described in [1]. First, the battery ECU 6 obtains the minimum temperature Tmin and the maximum temperature Tmax within the battery (step S1). Next, the cooling mode set by the user operating the user interface 9 is obtained (step S2).

[0094] Next, the temperature adjustment control unit 7 compares the following four values.

[0095] Minimum temperature Tmin inside the battery

[0096] Maximum temperature Tmax inside the battery

[0097] The upper limit temperature of the battery that allows the cooling device 4 to operate, To_up, which allows the cooling device 4 to operate.

[0098] The battery lower temperature limit To_down for cooling device operation that allows cooling device 4 to operate

[0099] Temperature control unit 7 determines whether the maximum battery temperature Tmax is equal to or higher than the upper battery temperature limit To_up, which allows the cooling device to operate, and whether the minimum battery temperature Tmin is equal to or higher than the lower battery temperature limit To_down, which allows the cooling device to operate (step S3). In other words, temperature control unit 7 determines whether the following equation (1) holds true.

[0100] Tmax≥To_up and Tmin≥To_down···(1)

[0101] When the condition of formula (1) is satisfied (step S3; yes), the temperature control unit 7 determines whether the set cooling mode is Figure 5 If the cooling mode is set to the cooling priority mode (step S4 ; yes), the temperature control unit 7 determines whether the maximum temperature Tmax in the battery is equal to or higher than the cooling target temperature Ttar1 , which is the target temperature in the cooling mode (step S5 ).

[0102] When the maximum temperature Tmax in the battery is equal to or higher than the cooling target temperature Ttar1 (Tmax ≥ Ttar1) (step S5; YES), the temperature control unit 7 sets the cooling state in which the cooling device 4 is turned on (operating state) and the heating device 5 is turned off (non-operating state) (step S6).

[0103] After cooling device 4 is turned on, temperature control unit 7 counts the operating time of cooling device 4 and determines whether the operating time is less than cooling device operating time t1 (step S7). If the operating time is less than cooling device operating time t1 (step S7; yes), temperature control unit 7 determines whether the maximum temperature Tmax inside the battery is less than or equal to the cooling target temperature Ttar1 (Tmax ≤ Ttar1) (step S8).

[0104] If the maximum temperature Tmax within the battery is below the cooling target temperature Ttar1 (Tmax ≤ Ttar1) (step S8: Yes), the temperature control unit 7 sets the cooling device 4 to a heating state (off) and the heating device 5 to an operating state (step S9). If the maximum temperature Tmax within the battery is not below the cooling target temperature Ttar1 in step S8 (step S8: No), the process returns to step S7, where the temperature control unit 7 counts the operating time of the cooling device 4.

[0105] When the temperature difference ΔT obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td is zero (step S10 ), the temperature control unit 7 sets the cooling device 4 to a stopped state (non-operating state) and the heating device 5 to a stopped state (step S11 ), and ends the process.

[0106] In step S7 , if the operating time of the cooling device 4 is longer than the cooling device operating time t1 (step S7 ; No), the temperature control unit 7 sets the heating state in which the cooling device 4 is turned off (non-operating state) and the heating device 5 is turned on (operating state) (step S12 ).

[0107] If the temperature difference ΔT obtained by subtracting the battery upper temperature Tu from the battery lower temperature Td is zero (step S13 ), the process returns to step S5 again and the processing after step S5 is repeated.

[0108] If the condition of formula (1) is not satisfied in step S3 (step S3; No), or if the maximum temperature Tmax in the battery is lower than the cooling target temperature Ttar1 in step S5 (step S5; No), the process proceeds to step S11, where the temperature control unit 7 sets the stop state and ends the process.

[0109] Then, Figure 5 The normal cooling mode shown in (b) of FIG. 1 is described below. In step S4, if the temperature control unit 7 determines that the set cooling mode is not the cooling priority mode (step S4: No), it then determines whether the set cooling mode is the normal cooling mode (step S14). If the set cooling mode is the normal cooling mode (step S14: Yes), the temperature control unit 7 determines whether the maximum temperature Tmax within the battery is greater than or equal to the cooling target temperature Ttar1, which is the target temperature in the cooling mode (step S15).

[0110] When the maximum temperature Tmax in the battery is equal to or higher than the cooling target temperature Ttar1 (Tmax ≥ Ttar1) (step S15; YES), the temperature control unit 7 sets the cooling state in which the cooling device 4 is turned on (operating state) and the heating device 5 is turned off (non-operating state) (step S16).

[0111] Furthermore, the temperature control unit 7 determines whether the maximum temperature Tmax within the battery is greater than the cooling target temperature Ttar1 (Tmax>Ttar1) (step S17). If the maximum temperature Tmax within the battery is greater than the cooling target temperature Ttar1 (step S17: Yes), the temperature control unit 7 determines whether the operating time of the cooling device 4 has exceeded the cooling device operating time t1 (step S18). If the operating time of the cooling device 4 has not exceeded the cooling device operating time t1 (step S18: No), the process returns to step S17 and the temperature control unit 7 determines whether the maximum temperature Tmax within the battery is greater than the cooling target temperature Ttar1.

[0112] In step S18 , if the operating time of the cooling device 4 exceeds the cooling device operating time t1 (step S18 ; YES), the temperature control unit 7 sets the heating state in which the cooling device 4 is turned off (non-operating state) and the heating device 5 is turned on (operating state) (step S19 ).

[0113] After the heater 5 is turned on, if the operating time of the heater 5 exceeds the heater operating time t2 (step S20), the process returns to step S15 and repeats the process from step S15 onward. However, if the maximum temperature Tmax within the battery is lower than the cooling target temperature Ttar1 in step S15 (step S15 returns No), the temperature control unit 7 proceeds to step S11, where it is set to the shutdown state and the process ends. Furthermore, if the maximum temperature Tmax within the battery is lower than the cooling target temperature Ttar1 in step S17 (step S17 returns No), the temperature control unit 7 proceeds to step S9 and performs the process from step S9 onward.

[0114] Next, use Figure 6 The follow-up Figure 7 right Figure 5 In step S14 , when the temperature control unit 7 determines that the set cooling mode is not the normal cooling mode (step S14 ; No), it determines that the set cooling mode is the output priority mode (step S21 ).

[0115] The temperature control unit 7 determines whether the maximum temperature Tmax in the battery is higher than the cooling target temperature Ttar1 (Tmax≥Ttar1) (step S22; yes). If the maximum temperature Tmax in the battery is higher than the cooling target temperature Ttar1 (Tmax≥Ttar1) (step S22; yes), the temperature control unit 7 sets a cooling state in which the cooling device 4 is turned on (operating state) and the heating device 5 is turned off (non-operating state) (step S23).

[0116] Next, the temperature control unit 7 determines whether the maximum temperature Tmax within the battery is lower than or equal to the cooling target temperature Ttar1 (step S24). If the maximum temperature Tmax within the battery is lower than or equal to the cooling target temperature Ttar1 (Tmax ≤ Ttar1) (step S24; yes), the temperature control unit 7 sets the cooling device 4 to a non-operating state and the heating device 5 to a heating state (step S25).

[0117] If the temperature difference ΔT, obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td, is zero (step S26), the temperature control unit 7 sets the cooling device 4 to a stopped state (non-operating state) and the heating device 5 to a stopped state (step S27), and the process ends. If, in step S22, the maximum internal battery temperature Tmax is less than the cooling target temperature Ttar1 (step S22: No), the process proceeds to step S27, where the temperature control unit 7 sets the stopped state and the process ends.

[0118] Furthermore, in step S24, if the maximum battery temperature Tmax is not equal to or lower than the cooling target temperature Ttar1 (step S24: No), the temperature control unit 7 determines whether the temperature difference ΔT, obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td, is equal to or lower than the predetermined allowable cooling temperature difference T1 (step S28). If the temperature difference ΔT is equal to or lower than the allowable cooling temperature difference T1 (step S28: Yes), the temperature control unit 7 sets the heating state to the state in which the cooling device 4 is turned off (non-operating state) and the heating device 5 is turned on (operating state) (step S29). If the temperature difference ΔT, obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td, is zero (step S30), the process returns to step S22, and the temperature control unit 7 repeats the process from step S22 onward.

[0119] If the temperature difference ΔT is not less than the cooling allowable temperature difference T1 in step S28 (step S28 ; No), the process returns to step S24 and the temperature adjustment control unit 7 determines whether the maximum temperature Tmax in the battery is less than the cooling target temperature Ttar1 .

[0120] As described above, in cooling mode, if the maximum internal battery temperature Tmax exceeds the cooling target temperature Ttar1 (steps S5, S15, and S22), the temperature control unit 7 sets the cooling state (steps S6, S16, and S23). Next, in the cooling state, if the maximum internal battery temperature Tmax falls below the cooling target temperature Ttar1 (steps S8, S17, and S24), the temperature control unit 7 switches from the cooling state to the heating state (steps S9 and S25). Furthermore, in the heating state, if the temperature difference ΔT, obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td, falls below a first predetermined value (in this example, ΔT = 0) (steps S10 and S26), the temperature control unit 7 switches from the heating state to the stopped state (steps S11 and S27).

[0121] Thus, when cooling the battery 3 , if the maximum temperature Tmax in the battery is lower than the cooling target temperature Ttar1 , the cooling state is switched to the heating state. This can suppress overcooling of the low temperature region and prevent the output of the battery 3 from being restricted.

[0122] In addition, Figure 5 In the cooling priority mode shown in (a), when the operating state of the cooling device 4 exceeds the cooling device operation time t1 before the maximum temperature Tmax in the battery becomes lower than the cooling target temperature Ttar1 (step S7), the temperature adjustment control unit 7 switches from the cooling state to the heating state (step S12). When the temperature difference ΔT obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td in the heating state becomes lower than a first predetermined value (ΔT=0 in this example) (step S13), the state is switched from the heating state to the cooling state (step S6).

[0123] As a result, the maximum temperature Tmax in the battery can be brought to the cooling target temperature Ttar1 in a short period of time.

[0124] In addition, Figure 5 In the normal cooling mode shown in (b), before the maximum temperature Tmax in the battery becomes lower than the cooling target temperature Ttar1 in the cooling state, when the operating state of the cooling device 4 exceeds the cooling device operating time t1 (step S18), the temperature adjustment control unit 7 switches from the cooling state to the heating state (step S19). When the operating state of the heating device 5 exceeds the heating device operating time t2 in the heating state (step S20), it switches from the heating state to the cooling state (step S16).

[0125] As a result, compared with the cooling priority mode, the maximum temperature Tmax in the battery can be brought to the cooling target temperature Ttar1 in a longer period of time, and the output of the battery 3 can be prevented from being restricted.

[0126] In addition, Figure 5 In the output priority mode shown in (c), when the temperature difference ΔT obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td in the cooling state is less than or equal to the allowable temperature difference T1 during cooling (step S28), the temperature adjustment control unit 7 switches from the cooling state to the heating state (step S29). When the temperature difference obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td in the heating state is less than or equal to a first predetermined value (ΔT=0 in this example) that is smaller than the allowable temperature difference T1 during cooling (step S30), the temperature adjustment control unit 7 switches from the heating state to the cooling state (step S23).

[0127] This makes it possible to reduce the region where the output of the battery 3 is limited and to make the maximum temperature Tmax in the battery reach the cooling target temperature Ttar1.

[0128] Figure 8 This is a graph showing the temperature inside the battery in a heating mode for heating the battery in a conventional battery temperature control system. Figure 8 The figure shows the temporal changes in the water temperature (refrigerant temperature), the minimum temperature within the battery, and the maximum temperature within the battery relative to the target temperature of the battery 3, which serves as a constant control target. The temperature near the upper battery region 32, namely the minimum temperature within the battery Tmin, takes time to approach the target temperature. Meanwhile, the temperature near the lower battery region 31, namely the maximum temperature within the battery Tmax, rises above the target temperature over time.

[0129] When the battery ECU 6 obtains the minimum battery temperature Tmin and the maximum battery temperature Tmax of the battery 3, it generally determines the allowable power of the battery 3 with reference to the minimum battery temperature Tmin. If the temperature difference within the battery 3 is not actively eliminated, the maximum battery temperature Tmax will remain high if the battery 3 is used continuously, and this may cause local performance degradation of the battery 3.

[0130] on the other hand, Figure 9 Graphs showing (a) the temperature inside the battery and (b) the water temperature (temperature of the coolant) in the heating mode for heating the battery 3 of the battery temperature control system 1 according to the present embodiment.

[0131] The battery ECU 6 obtains the lower battery temperature Td of the lower battery region 31 and the upper battery temperature Tu of the upper battery region 32, and calculates the maximum battery temperature Tmax and the minimum battery temperature Tmin. The method for calculating the maximum battery temperature Tmax and the minimum battery temperature Tmin is not particularly limited and can be calculated in the same manner as during cooling. The temperature control unit 7 refers to the minimum battery temperature Tmin and the maximum battery temperature Tmax of the battery 3 to switch between the cooling state, the heating state, and the stopped state as described above.

[0132] When heating the battery 3, the temperature control unit 7 selects a heating state in which the heating device 5 is in operation and the cooling device 4 is in non-operation. In the heating state, the battery upper temperature Tu (the minimum temperature inside the battery Tmin) and the battery lower temperature Td (the maximum temperature inside the battery Tmax) rise. Figure 9As shown in (a), after the battery upper temperature Tu (the maximum temperature in the battery Tmax) exceeds the target temperature (P1), the temperature control unit 7 selects a cooling state in which the cooling device 4 is in the operating state and the heating device 5 is in the non-operating state. Figure 9 As shown in (b), the water temperature begins to drop, and as the battery lower temperature Td in the battery lower region 31 close to the water jacket 11 decreases, the maximum temperature Tmax in the battery begins to drop (P2).

[0133] When the battery lower temperature Td (maximum battery temperature Tmax) significantly drops below the target temperature (P3) after a predetermined time in the cooling state, the temperature control unit 7 switches to the heating state, where the cooling device 4 is inoperative and the heating device 5 is inoperative. Figure 9 As shown in (b), the water temperature starts to rise (P4), and the battery lower temperature Td (the maximum temperature in the battery Tmax) starts to rise. Thereafter, the temperature control unit 7 and the battery ECU 6 repeat the same operation.

[0134] In this manner, the temperature adjustment control unit 7 can prevent local performance degradation of the battery 3 by eliminating temperature differences inside the battery 3 and bringing the temperature of the battery 3 close to the target temperature.

[0135] Figure 10 Graphs showing the temperature inside the battery and the water temperature in heating modes in which the battery temperature control system 1 heats the battery 3 , more specifically, in two modes: (a) the heating priority mode and (b) the active protection mode.

[0136] exist Figure 10 In the heating priority mode (a), switching from the heating state to the cooling state is performed at the following timing, for example.

[0137] When the operating time of the heating device 5 has exceeded the prescribed time

[0138] The time when the temperature difference ΔT (ΔT = Td - Tu, the same applies hereinafter) obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td exceeds the specified allowable temperature difference T3 during heating (ΔT > T3)

[0139] In addition, switching from the cooling state to the heating state is performed, for example, at the following timing.

[0140] When the operating time of the cooling device 4 exceeds the predetermined time

[0141] The time when the temperature difference ΔT becomes less than the specified allowable temperature difference T4 during cooling (ΔT ≤ T4)

[0142] According to this mode, the minimum temperature Tmin in the battery reaches the target temperature within an appropriate time.

[0143] exist Figure 10 In the active protection mode (b), switching from the heating state to the cooling state is performed at the following timing, for example.

[0144] The moment when the maximum temperature Tmax inside the battery reaches the upper limit temperature allowed during heating, that is, the upper limit temperature allowed during heating Tht (Tmax = Tht)

[0145] In addition, switching from the cooling state to the heating state is performed, for example, at the following timing.

[0146] The moment when the temperature difference ΔT becomes zero (ΔT = 0)

[0147] The time when the temperature difference ΔT becomes less than the specified allowable temperature difference T4 during cooling (ΔT ≤ T4)

[0148] According to this mode, the maximum temperature Tmax in the battery does not exceed the heating permission upper limit temperature Tht, so the durability of the battery 3 can be maintained for a long time. On the other hand, the heating time until the minimum temperature Tmin in the battery reaches the target temperature is prolonged.

[0149] Figure 11 It is used to execute Figure 10 Flowchart of the steps of the heating mode described in . First, the battery ECU 6 obtains the minimum temperature Tmin and the maximum temperature Tmax in the battery (step S41 ). Next, the heating mode set by the user operation of the user interface 9 is obtained (step S42 ).

[0150] Next, the temperature adjustment control unit 7 compares the following four values.

[0151] Minimum temperature Tmin inside the battery

[0152] Maximum temperature Tmax inside the battery

[0153] The upper limit temperature of the battery that allows the heating device 5 to operate is Too_up.

[0154] Too_down, the lower limit temperature of the battery that allows the heating device 5 to operate

[0155] The temperature control unit 7 determines whether the maximum temperature Tmax in the battery is lower than the upper limit temperature Too_up for enabling heating operation, and whether the minimum temperature Tmin in the battery is lower than the lower limit temperature Too_down for enabling heating operation (step S43). In other words, the temperature control unit 7 determines whether the following equation (2) holds true.

[0156] Tmax≤Too_up and Tmin≤Too_down···(2)

[0157] When the condition of formula (2) is satisfied (step S43; yes), the temperature control unit 7 determines whether the set heating mode is Figure 10 If the heating mode is set to the heating priority mode (step S44; yes), the temperature control unit 7 determines whether the minimum temperature Tmin in the battery is lower than the heating target temperature Ttar2, which is the target temperature in the heating mode (step S45).

[0158] When the minimum temperature Tmin in the battery is lower than the heating target temperature Ttar2 (Tmin<Ttar2) (step S45; YES), the temperature control unit 7 sets the heating state in which the heating device 5 is turned on (operating state) and the cooling device 4 is turned off (non-operating state) (step S46).

[0159] After turning on the heater 5, the temperature control unit 7 counts the operating time of the heater 5 and determines whether the operating time is less than the heater operating time t3 (step S47). If the operating time is less than the heater operating time t3 (step S47: Yes), the temperature control unit 7 determines whether the minimum temperature Tmin within the battery is greater than or equal to the heating target temperature Ttar2 (Tmin ≥ Ttar2) (step S48).

[0160] If the minimum temperature Tmin within the battery is equal to or higher than the heating target temperature Ttar2 (step S48: Yes), the temperature control unit 7 sets the heating device 5 to a cooling state (step S49), turning off the heating device 5 (non-operating state) and turning on the cooling device 4 (operating state). If the minimum temperature Tmin within the battery is not equal to or higher than the heating target temperature Ttar2 in step S48 (step S48: No), the process returns to step S47, where the temperature control unit 7 counts the operating time of the heating device 5.

[0161] If the temperature difference ΔT obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td is zero (step S50 ), the temperature adjustment control unit 7 sets the heating device 5 to a stopped state (non-operating state) and the cooling device 4 to a stopped state (step S51 ), and ends the process.

[0162] In step S47 , when the operating time of the heating device 5 is not less than the heating device operating time t3 (step S47 ; No), the temperature adjustment control unit 7 sets the cooling state in which the heating device 5 is turned off (non-operating state) and the cooling device 4 is turned on (operating state) (step S52 ).

[0163] After the cooling device 4 is turned on, if the operating time exceeds the cooling device operating time t4 (step S53 ), the process returns to step S45 again and the processing after step S45 is repeated.

[0164] If the condition of formula (2) is not satisfied in step S43 (step S43; No), or if the minimum temperature Tmin in the battery is not less than the heating target temperature Ttar2 in step S45 (step S45; No), the process proceeds to step S51, where the temperature adjustment control unit 7 sets the stop state and ends the process.

[0165] Then, Figure 10 In step S44 , when the temperature control unit 7 determines that the set heating mode is not the heating priority mode (step S44 ; No), it determines that the set heating mode is the active protection mode (step S54 ).

[0166] When the minimum temperature Tmin in the battery is lower than the heating target temperature Ttar2 (Tmin<Ttar2) (step S55; YES), the temperature control unit 7 sets the heating state in which the heating device 5 is turned on (operating state) and the cooling device 4 is turned off (non-operating state) (step S56).

[0167] If the maximum temperature Tmax inside the battery reaches the upper limit temperature Tht allowed for heating (Tmax=Tht) (step S57), the temperature control unit 7 determines whether the minimum temperature Tmin inside the battery is lower than the heating target temperature Ttar2 (step S58). If the minimum temperature Tmin inside the battery is lower than the heating target temperature Ttar2 (Tmin<Ttar2) (step S58; yes), the temperature control unit 7 sets the cooling state in which the heating device 5 is turned off (non-operating state) and the cooling device 4 is turned on (operating state) (step S59).

[0168] If the temperature difference ΔT, obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td, is zero (step S60), the process returns to step S55 and repeats the process from step S55 onward. However, if the minimum battery temperature Tmin is not less than the heating target temperature Ttar2 in step S55 (step S55 returns No), the temperature control unit 7 proceeds to step S51, sets the temperature control unit 7 to a stop state, and terminates the process. Furthermore, if the minimum battery temperature Tmin is not less than the heating target temperature Ttar2 in step S58 (step S58 returns No), the temperature control unit 7 proceeds to step S49 and performs the process from step S49 onward.

[0169] As described above, in heating mode, when the minimum battery temperature Tmin is lower than the heating target temperature Ttar2 (steps S45 and S55), the temperature control unit 7 sets the heating mode (steps S46 and S56). Next, when the minimum battery temperature Tmin is higher than the heating target temperature Ttar2 in the heating mode (steps S48 and S58), the temperature control unit 7 switches from the heating mode to the cooling mode (steps S49 and S59). Furthermore, when the temperature difference ΔT, obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td in the cooling mode, is less than or equal to a first predetermined value (ΔT = 0 in this example) (step S50), the temperature control unit 7 switches from the cooling mode to the stopped mode (step S51).

[0170] Thus, when heating the battery 3 , when the minimum temperature Tmin in the battery is equal to or higher than the heating target temperature Ttar2 , the state is switched from the heating state to the cooling state, thereby suppressing excessive heating of the high temperature side region.

[0171] In addition, Figure 10 In the heating priority mode shown in (a), before the minimum temperature Tmin in the battery becomes equal to or higher than the heating target temperature Ttar2 in the heating state, when the operating state of the heating device 5 exceeds the heating device operating time t3 (step S47), the temperature adjustment control unit 7 switches from the heating state to the cooling state (step S52), and when the operating state of the cooling device 4 exceeds the cooling device operating time t4 in the cooling state (step S53), it switches from the cooling state to the heating state (step S46).

[0172] This can suppress excessive heating of the high temperature side region and make the minimum temperature Tmin in the battery reach the heating target temperature Ttar2 within an appropriate time.

[0173] In addition, Figure 10 In the active protection mode shown in (b), in the heating state, when the maximum temperature Tmax in the battery reaches the heating permission upper limit temperature Tht before the minimum temperature Tmin in the battery reaches or exceeds the heating target temperature Ttar2 (step S57), the temperature adjustment control unit 7 switches from the heating state to the cooling state (step S59). In the cooling state, when the temperature difference ΔT obtained by subtracting the upper battery temperature Tu from the lower battery temperature Td is equal to or less than a first predetermined value (ΔT=0 in this example) (step S60), the state is switched from the cooling state to the heating state (step S56).

[0174] This makes it possible to prevent the maximum temperature Tmax in the battery from exceeding the heating permission upper limit temperature Tht while making the minimum temperature Tmin in the battery reach the heating target temperature Ttar2 , thereby suppressing degradation of the battery 3 .

[0175] While various embodiments have been described above with reference to the accompanying drawings, the present invention is not limited to these examples. It is apparent that those skilled in the art will be able to devise various variations or modifications within the scope of the claims, and it should be understood that these variations and modifications also fall within the technical scope of the present invention. Furthermore, the various components of the above embodiments may be arbitrarily combined without departing from the spirit of the invention.

[0176] For example, the storage battery 3 is not limited to a laminated type cell, and may be a can type cell or a cylindrical type cell.

[0177] The present specification includes at least the following matters: Although corresponding components and the like in the above-described embodiment are shown in parentheses, the present invention is not limited thereto.

[0178] (1) A battery temperature control system (battery temperature control system 1), comprising:

[0179] Battery (Battery 3);

[0180] a cooling unit (cooling device 4 ) for cooling the battery;

[0181] a heating unit (heating device 5 ) that heats the battery;

[0182] a temperature acquisition unit (battery ECU 6 ) that acquires the temperature of the battery; and

[0183] A temperature control unit (temperature control unit 7) controls the cooling unit and the heating unit.

[0184] The temperature control unit can switch between cooling, heating and stopping states.

[0185] In the cooling state, the cooling unit is in an operating state and the heating unit is in a non-operating state.

[0186] In the heating state, the cooling unit is in a non-operating state and the heating unit is in an operating state.

[0187] In the stopped state, the cooling unit is in a non-operating state and the heating unit is in a non-operating state.

[0188] When the temperature of the battery is brought close to the target temperature (cooling target temperature Ttar1 , heating target temperature Ttar2 ), the cooling state and the heating state are switched at least once.

[0189] According to (1), the battery temperature can be brought close to the target temperature while eliminating temperature differences within the battery. This can prevent the battery output from being limited due to a localized decrease in temperature or the battery from being degraded due to a localized increase in temperature.

[0190] (2) The battery temperature control system according to (1), wherein:

[0191] The temperature adjustment control unit switches between the cooling state and the heating state multiple times in succession.

[0192] According to (2), it is possible to more reliably suppress an increase in temperature difference within the battery.

[0193] (3) The battery temperature control system according to (1), wherein:

[0194] The battery temperature control system includes an output control unit (battery ECU 6 ) that controls the output of the battery.

[0195] The temperature acquisition unit acquires temperatures of a plurality of locations of the battery.

[0196] The output control unit controls the output of the battery based on a low-temperature temperature (a minimum temperature Tmin in the battery) among the temperatures of the plurality of locations.

[0197] According to (3), in an environment where the battery output is controlled based on the low-side temperature of the battery, by eliminating temperature differences within the battery while bringing the battery temperature close to the target temperature, it is possible to prevent the battery output from being restricted due to a local decrease in the battery temperature.

[0198] (4) The battery temperature control system according to (1), wherein:

[0199] The temperature acquisition unit acquires temperatures of a plurality of locations of the battery.

[0200] The switching between the cooling state and the heating state is performed based on the temperature difference (temperature difference ΔT) between the high-temperature side temperature and the low-temperature side temperature.

[0201] According to (4), it is possible to suppress the temperature difference between the high-temperature side temperature and the low-temperature side temperature of the battery from increasing beyond a predetermined value.

[0202] (5) The battery temperature control system according to (1), wherein:

[0203] The switching between the cooling state and the heating state is based on the operating time of the cooling unit or the heating unit.

[0204] According to (5), the temperature difference between the high-temperature side temperature and the low-temperature side temperature of the battery can be suppressed from increasing beyond a predetermined value, and control can be easily performed.

[0205] (6) The battery temperature control system according to (1), wherein:

[0206] The temperature control unit is configured to be able to perform temperature control on the battery in a plurality of modes having different switching conditions between the cooling state and the heating state.

[0207] The multiple modes are set according to user requirements.

[0208] According to (6), the temperature control of the battery can reflect the user's request.

[0209] (7) The battery temperature control system according to (1), wherein:

[0210] The temperature acquisition unit acquires temperatures of a plurality of locations of the battery.

[0211] The temperature control unit sets the state to the cooling state when the high temperature side temperature (the maximum temperature Tmax in the battery) is higher than the target temperature (the cooling target temperature Ttar1).

[0212] The temperature control unit switches from the cooling state to the heating state when the high temperature side temperature becomes lower than the target temperature in the cooling state.

[0213] The temperature adjustment control unit switches from the heating state to the stop state when a temperature difference (temperature difference ΔT) between the high temperature side temperature and the low temperature side temperature in the heating state is equal to or smaller than a first predetermined value (ΔT=0).

[0214] According to (7), when cooling the battery, if the high temperature side temperature is lower than the target temperature, the cooling state is switched to the heating state, thereby suppressing overcooling of the low temperature side region and preventing the battery output from being restricted.

[0215] (8) The battery temperature control system according to (7), wherein:

[0216] When the operating state of the cooling unit elapses for a first time (cooling device operating time t1) before the high temperature side temperature becomes lower than the target temperature in the cooling state, the cooling state is switched to the heating state.

[0217] When the temperature difference between the high-temperature side temperature and the low-temperature side temperature in the heating state is equal to or smaller than a first predetermined value (ΔT=0), the heating state is switched to the cooling state.

[0218] According to (8), the temperature of the battery can be brought to the target temperature in a short time.

[0219] (9) The battery temperature control system according to (7), wherein:

[0220] When the operating state of the cooling unit elapses for a first time (cooling device operating time t1) before the high temperature side temperature becomes lower than the target temperature in the cooling state, the cooling state is switched to the heating state.

[0221] When the operating state of the heating unit in the heating state elapses for a second time (heating device operating time t2 ), the heating state is switched to the cooling state.

[0222] According to (9), the temperature of the battery can be brought to the target temperature within an appropriate time, and the output of the battery can be prevented from being restricted.

[0223] (10) The battery temperature control system according to (7), wherein:

[0224] When the temperature difference between the low-temperature side temperature and the high-temperature side temperature in the cooling state is equal to or smaller than a second predetermined value (ΔT=T1), the cooling state is switched to the heating state.

[0225] When the temperature difference between the high temperature side temperature and the low temperature side temperature in the heating state is equal to or smaller than a first predetermined value (ΔT=0) smaller than the second predetermined value, the heating state is switched to the cooling state.

[0226] According to (10), the region where the battery output is limited can be reduced while the battery temperature can be brought to the target temperature.

[0227] (11) The battery temperature control system according to (7), wherein:

[0228] The temperature acquisition unit acquires temperatures of a plurality of locations of the battery.

[0229] The temperature control unit sets the state to the heating state when the low temperature side temperature (the lowest temperature Tmin in the battery) is lower than the target temperature (the heating target temperature Ttar2).

[0230] The temperature control unit switches from the heating state to the cooling state when the low-temperature side temperature becomes equal to or higher than the target temperature in the heating state.

[0231] The temperature adjustment control unit switches from the cooling state to the stopped state when the temperature difference between the high-temperature side temperature and the low-temperature side temperature is equal to or smaller than a first predetermined value (ΔT=0) in the cooling state.

[0232] According to (11), when the low-temperature side temperature is equal to or higher than the target temperature during battery heating, the state is switched from the heating state to the cooling state, thereby suppressing excessive heating of the high-temperature side region.

[0233] (12) The battery temperature control system according to (11), wherein:

[0234] When the operating state of the heating unit elapses for a third time (heating device operating time t3) before the low temperature side temperature becomes equal to or higher than the target temperature in the heating state, the heating state is switched to the cooling state.

[0235] When the operating state of the cooling unit in the cooling state elapses for a fourth time (cooling device operation time t4 ), the cooling state is switched to the heating state.

[0236] According to (12), it is possible to suppress overheating of the high temperature side region and to make the temperature of the battery reach the target temperature within an appropriate time.

[0237] (13) The battery temperature control system according to (11), wherein:

[0238] When the high temperature side temperature reaches the heating permission upper limit temperature (heating permission upper limit temperature Tht) before the low temperature side temperature reaches or exceeds the target temperature in the heating state, the heating state is switched to the cooling state.

[0239] When the temperature difference between the high-temperature side temperature and the low-temperature side temperature in the cooling state is equal to or smaller than a first predetermined value (ΔT=0), the cooling state is switched to the heating state.

[0240] According to (13), the battery temperature can be brought to the target temperature while preventing the battery temperature from exceeding the heating permission upper limit temperature, and degradation of the battery can be suppressed.

[0241] (14) The battery temperature control system according to any one of (1) to (13), wherein:

[0242] The battery temperature control system includes a temperature control circuit (temperature control circuit 12), which is connected to the cooling unit, the heating unit, and a water jacket (water jacket 11) that is in direct or indirect contact with one side of the battery and is used for circulation of a heat transfer medium.

[0243] The temperature acquisition unit acquires a temperature of the one surface side of the storage battery and a temperature of a side opposite to the one surface side.

[0244] According to (14), the side of the battery that the water jacket directly or indirectly contacts is greatly affected by the temperature control circuit. Therefore, by obtaining the temperature of one side of the battery and the temperature of the opposite side, the temperature of the battery can be appropriately managed.

Claims

1. A battery temperature control system comprising: batteries; a cooling unit for cooling the battery; a heating unit that heats the battery; a temperature acquiring unit configured to acquire the temperature of the battery; and a temperature control unit that controls the cooling unit and the heating unit, in, The temperature control unit can switch between cooling state, heating state and stop state. In the cooling state, the cooling unit is in an operating state and the heating unit is in a non-operating state. In the heating state, the cooling unit is in a non-operating state and the heating unit is in an operating state. In the stopped state, the cooling unit is in a non-operating state and the heating unit is in a non-operating state. When the temperature of the battery is brought close to a target temperature, the cooling state and the heating state are switched at least once.

2. The battery temperature control system according to claim 1, wherein: The temperature adjustment control unit switches between the cooling state and the heating state multiple times in succession.

3. The battery temperature control system according to claim 1, wherein: The battery temperature control system includes an output control unit that controls the output of the battery. The temperature acquisition unit acquires temperatures of a plurality of locations of the battery. The output control unit controls the output of the battery based on a low-temperature temperature among the temperatures of the plurality of locations.

4. The battery temperature control system according to claim 1, wherein: The temperature acquisition unit acquires temperatures of a plurality of locations of the battery. The switching between the cooling state and the heating state is performed based on the temperature difference between the high-temperature side temperature and the low-temperature side temperature.

5. The battery temperature control system according to claim 1, wherein: The switching between the cooling state and the heating state is based on the operating time of the cooling unit or the heating unit.

6. The battery temperature control system according to claim 1, wherein: The temperature control unit is configured to be able to perform temperature control on the battery in a plurality of modes having different switching conditions between the cooling state and the heating state. The multiple modes are set according to user requirements.

7. The battery temperature control system according to claim 1, wherein: The temperature acquisition unit acquires temperatures of a plurality of locations of the battery. The temperature control unit is set to the cooling state when the high temperature side temperature is higher than the target temperature. The temperature control unit switches from the cooling state to the heating state when the high temperature side temperature becomes lower than the target temperature in the cooling state. The temperature adjustment control unit switches from the heating state to the stop state when the temperature difference between the high-temperature side temperature and the low-temperature side temperature is equal to or smaller than a first predetermined value in the heating state.

8. The battery temperature control system according to claim 7, wherein: When the operating state of the cooling unit elapses for a first time before the high temperature side temperature becomes lower than the target temperature in the cooling state, the cooling state is switched to the heating state. When the temperature difference between the high-temperature side temperature and the low-temperature side temperature in the heating state is equal to or smaller than a first predetermined value, the heating state is switched to the cooling state.

9. The battery temperature control system according to claim 7, wherein: When the operating state of the cooling unit elapses for a first time before the high temperature side temperature becomes lower than the target temperature in the cooling state, the cooling state is switched to the heating state. When the operating state of the heating unit in the heating state elapses for a second time, the heating state is switched to the cooling state.

10. The battery temperature control system according to claim 7, wherein: When the temperature difference between the low-temperature side temperature and the high-temperature side temperature in the cooling state is equal to or smaller than a second predetermined value, the cooling state is switched to the heating state. When the temperature difference between the high-temperature side temperature and the low-temperature side temperature in the heating state is equal to or smaller than a first predetermined value that is smaller than the second predetermined value, the heating state is switched to the cooling state.

11. The battery temperature control system according to claim 7, wherein: The temperature acquisition unit acquires temperatures of a plurality of locations of the battery. The temperature control unit is set to the heating state when the low temperature side temperature is lower than the target temperature. The temperature control unit switches from the heating state to the cooling state when the low-temperature side temperature becomes equal to or higher than the target temperature in the heating state. The temperature adjustment control unit switches from the cooling state to the stopped state when the temperature difference between the high-temperature side temperature and the low-temperature side temperature is equal to or smaller than a first predetermined value in the cooling state.

12. The battery temperature control system according to claim 11, wherein: When the operating state of the heating unit elapses for a third time before the low-temperature side temperature becomes equal to or higher than the target temperature in the heating state, the heating state is switched to the cooling state. When the operating state of the cooling unit in the cooling state elapses for a fourth time, the cooling state is switched to the heating state.

13. The battery temperature control system according to claim 11, wherein: When the high-temperature side temperature reaches the upper limit temperature of heating permission before the low-temperature side temperature reaches or exceeds the target temperature in the heating state, the heating state is switched to the cooling state. When the temperature difference between the high-temperature side temperature and the low-temperature side temperature in the cooling state is equal to or smaller than a first predetermined value, the cooling state is switched to the heating state.

14. The battery temperature control system according to any one of claims 1 to 13, wherein: The battery temperature control system includes a temperature control circuit, which is connected to the cooling unit, the heating unit, and a water jacket that is in direct or indirect contact with one side of the battery and is used for circulation of a heat transfer medium. The temperature acquisition unit acquires a temperature of the one surface side of the storage battery and a temperature of a side opposite to the one surface side.

Images