Heat management system

Abstract

[Problem] To provide a heat management system which is capable of inhibiting dispersion of measurement data of a battery due to requests from other on-vehicle equipment such as an air conditioning device, and enhancing estimation accuracy of a degradation state of the battery. [Solution] A heat management system 100 has an on-vehicle battery 55, a temperature adjustment unit 61 for performing temperature adjustment of the on-vehicle battery 55, and a control device 32. The control device 32: has a storage unit 323 for storing information of the on-vehicle battery 55 during charging, and an estimation unit 327 for estimating the degree of degradation of the on-vehicle battery 55 on the basis of the information; and corrects an operation condition for the temperature adjustment unit on the basis of an estimation result from the estimation unit 327.

Description

Thermal Management System

[0001] The present invention relates to a thermal management system for a vehicle.

[0002] Conventionally, in a vehicle thermal management system for an electric vehicle or a plug-in hybrid vehicle, which drives a traction motor with power supplied from a battery mounted on the vehicle, the temperature of the battery (e.g., battery cooling) is adjusted in response to a request from the vehicle. However, if the vehicle requests temperature adjustment (temperature control) regardless of the state of deterioration of the battery, adjusting the temperature of the battery (e.g., cooling) in response to the request may accelerate deterioration of the battery.

[0003] As a technology for adjusting the temperature of a battery according to its deterioration state, for example, a technology for correcting a preset target temperature of a storage battery based on the internal resistance and remaining capacity of the storage battery is known (see, for example, Patent Document 1). Specifically, Patent Document 1 describes a configuration in which, when the remaining capacity of the storage battery at the start of charging is less than a predetermined value and a long charging time is expected, the target temperature is corrected to a lower temperature as the degree of deterioration according to the internal resistance of the storage battery increases.

[0004] International Publication No. 2017 / 056161

[0005] However, the technology described in Patent Document 1 does not fully consider how to grasp (estimate, predict) the specific state of battery degradation. For example, when other in-vehicle devices such as an air conditioner are operating, the battery load frequently fluctuates, which causes variations in the measurement data used to grasp the battery capacity. Even if the state of battery degradation is grasped based on such varied measurement data and the battery temperature is adjusted, it is difficult to actually suppress the progression of battery degradation.

[0006] In view of the above situation, the present invention aims to provide a thermal management system that can reduce the variation in battery measurement data due to the requirements of other on-board equipment such as air conditioning systems, and improve the accuracy of estimating the battery's deterioration state.

[0007] The present invention relates to a thermal management system having an on-board battery, a temperature control unit that adjusts the temperature of the on-board battery, and a control device, wherein the control device has a memory unit that stores information about the on-board battery while it is being charged, and an estimation unit that estimates the degree of deterioration of the on-board battery based on the information, and corrects the operating conditions of the temperature control unit based on the estimation results of the estimation unit.

[0008] According to the present invention, it is possible to achieve the excellent effect of providing a thermal management system that can reduce variations in battery measurement data due to requirements from other on-board equipment such as air conditioning systems, and improve the accuracy of estimating the battery's deterioration state.

[0009] FIG. 1 is a diagram showing a schematic configuration of a vehicle air conditioning device employing a thermal management system according to an embodiment of the present invention. FIG. 2 is a block diagram showing a schematic configuration of a control device of a thermal management system according to an embodiment of the present invention. FIG. 3 is a functional block diagram of a control device of a thermal management system according to an embodiment of the present invention. FIG. 4 is a conceptual diagram explaining a method for estimating a deterioration level of a battery in a thermal management system according to an embodiment of the present invention. FIG. 5 is a conceptual diagram explaining air conditioning control in a thermal management system according to an embodiment of the present invention. FIG. 6 is a flow chart showing the flow of a temperature adjustment control process in a thermal management system according to an embodiment of the present invention.

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Figures 1 to 7 show an example of an embodiment of the present invention, and in the figures, parts with the same reference numerals indicate parts with the same functions, and duplicated explanations in each figure will be omitted as appropriate.

[0011] In this embodiment, a vehicle air conditioning device 1 employing a heat management system 100 will be described as an example.

[0012] FIG. 1 is a schematic diagram showing an example of a vehicle air conditioning device 1 according to an embodiment of the present invention. The vehicle air conditioning device 1 can be applied to vehicles such as electric vehicles (EVs) that do not have an internal combustion engine or so-called hybrid vehicles that use both an engine and an electric motor for driving. Such vehicles are equipped with an on-board battery 55 and are driven by supplying power charged in the battery 55 from an external power source to a motor unit 65 that includes a driving motor (electric motor). The on-board battery 55 (hereinafter simply referred to as "battery 55") is, for example, a lithium battery. The vehicle air conditioning device 1 is also driven by power supplied from the battery 55.

[0013] That is, the thermal management system 100 of this embodiment, for example, air-conditions the passenger compartment of a vehicle and regulates the temperature of temperature-controlled objects (such as the battery 55 and motor unit 65) mounted on the vehicle, and is equipped with a heat medium circuit that circulates a heat medium that has exchanged heat with a heat source to the temperature-controlled objects, and a control device that controls the heat medium circuit to regulate the temperature of each temperature-controlled object.

[0014] Referring to FIG. 1 , the vehicle air conditioning device 1 includes, for example, an air conditioning unit (air conditioning circuit) 60 that includes a refrigerant circuit R for performing heat pump operation and performs air conditioning (heating, cooling, dehumidification, and ventilation) within the vehicle cabin, and a temperature adjustment unit (equipment temperature adjustment circuit) 61 that adjusts the temperature of heat-generating devices (temperature-controlled devices) such as a battery 55 and a motor unit 65. The device temperature adjustment circuit 61 is a heat medium circuit in which a heat medium (e.g., water) different from the refrigerant circuit R circulates, and is connected to the refrigerant circuit R in parallel via a refrigerant-heat medium heat exchanger 64, which will be described later. The vehicle air conditioning device 1 performs air conditioning within the vehicle cabin and temperature adjustment of the temperature-controlled devices such as the battery 55 and the motor unit 65 by selectively performing air conditioning operations such as heating operation and cooling operation through heat pump operation using the refrigerant circuit R.

[0015] <Air conditioning section> The refrigerant circuit R constituting the air conditioning unit 60 is configured by an electric compressor (electric compressor) 2 that compresses the refrigerant, a condenser 4 that is provided in an air flow passage 3 of the HVAC system 10 through which air inside the vehicle cabin is circulated and that serves as a heat radiating section (indoor heat exchanger, heating section) that radiates heat from the high-temperature, high-pressure refrigerant discharged from the compressor 2 to heat the air to be supplied into the vehicle cabin, an outdoor expansion valve 6 that serves as a pressure reducing section that decompresses and expands the refrigerant during heating, an outdoor heat exchanger (radiator) 7 that performs heat exchange between the refrigerant and outside air to function as a radiator (condenser) that radiates heat from the refrigerant during cooling and as an evaporator that absorbs heat from the refrigerant during heating, an indoor expansion valve 8 that serves as a pressure reducing section that decompresses and expands the refrigerant, an evaporator 9 that is provided in the air flow passage 3 and that serves as a heat absorbing section that causes the refrigerant to absorb heat from inside and outside the vehicle cabin during cooling (dehumidifying) to cool the air to be supplied into the vehicle cabin, and an accumulator 12, etc., which are connected by refrigerant pipes 13A to 13H.

[0016] Electronic expansion valves can be used for both the outdoor expansion valve 6 and the indoor expansion valve 8. The outdoor expansion valve 6 reduces the pressure and expands the refrigerant that flows out of the condenser 4 and into the outdoor heat exchanger 7, and can also be fully closed. The indoor expansion valve 8 reduces the pressure and expands the refrigerant that flows into the evaporator 9, and adjusts the heat absorption power of the refrigerant in the evaporator 9, i.e., the cooling capacity of the air passing through.

[0017] The refrigerant outlet of the outdoor heat exchanger 7 and the refrigerant inlet of the evaporator 9 are connected by a refrigerant pipe 13A. A check valve 18 and an indoor expansion valve 8 are provided in the refrigerant pipe 13A, in this order from the outdoor heat exchanger 7 side. The check valve 18 is provided in the refrigerant pipe 13A so that the direction toward the evaporator 9 is the forward direction. The refrigerant pipe 13A branches into a refrigerant pipe 13B at a position closer to the outdoor heat exchanger 7 than the check valve 18.

[0018] Refrigerant pipe 13B branching off from refrigerant pipe 13A is connected to the refrigerant inlet of accumulator 12. Refrigerant pipe 13B is provided with, in this order from the exterior heat exchanger 7 side, a solenoid valve 21 that opens during heating and a check valve 20. Check valve 20 is connected so that the direction toward accumulator 12 is the forward direction. Refrigerant pipe 13B branches off to refrigerant pipe 13C between solenoid valve 21 and check valve 20. Refrigerant pipe 13C branching off from refrigerant pipe 13B is connected to the refrigerant outlet of evaporator 9. The refrigerant outlet of accumulator 12 and compressor 2 are connected by refrigerant pipe 13D.

[0019] The refrigerant outlet of the compressor 2 and the refrigerant inlet of the condenser 4 are connected by a refrigerant pipe 13E. One end of a refrigerant pipe 13F is connected to the refrigerant outlet of the condenser 4, and the other end of the refrigerant pipe 13F branches into a refrigerant pipe 13G and a refrigerant pipe 13H before the outdoor expansion valve 6 (on the refrigerant upstream side). One of the branched refrigerant pipes, 13H, is connected to the refrigerant inlet side of the outdoor heat exchanger 7 via the outdoor expansion valve 6. The other branched refrigerant pipe 13G is connected between the check valve 18 of the refrigerant pipe 13A and the indoor expansion valve 8. A solenoid valve 22 is provided on the refrigerant upstream side of the connection point of the refrigerant pipe 13G with the refrigerant pipe 13A.

[0020] As a result, the refrigerant pipe 13G is connected in parallel to the series circuit of the outdoor expansion valve 6, the outdoor heat exchanger 7 and the check valve 18, and becomes a circuit that bypasses the outdoor expansion valve 6, the outdoor heat exchanger 7 and the check valve 18.

[0021] The HVAC system 10 houses a condenser 4 and an evaporator 9, and an (air) intake unit 10I is provided in the air flow passage 3 on the air upstream side of the evaporator 9. The intake unit 10I includes, for example, an outside air inlet and an inside air inlet (representatively shown as an inlet 25 in FIG. 1 ), an inlet switching damper 26, and an interior blower (blower fan) 27. The intake unit 10I uses the inlet switching damper 26 to appropriately switch between inside air (inside air circulation) that is air inside the vehicle cabin and outside air (outside air introduction) that is air outside the vehicle cabin, and introduces the air into the air flow passage 3 through the inlet 25. The interior blower (blower fan) 27 is provided on the air downstream side of the inlet switching damper 26 and supplies the introduced inside air and outside air to the air flow passage 3. Furthermore, in the air flow passage 3 on the air downstream side of the condenser 4, there are formed air outlets for FOOT, VENT, and DEF (shown representatively as air outlet 29 in FIG. 1), and this air outlet 29 is provided with an air outlet switching damper 31 that switches and controls the air blowing out from each of the above air outlets.

[0022] 1, an auxiliary heater 23 is provided as an auxiliary heating device. The auxiliary heater 23 is, for example, a PTC heater (electric heater), and is provided in the air flow passage 3 downstream of the condenser 4 with respect to the air flow in the air flow passage 3. When the auxiliary heater 23 is energized and generates heat, it can supplement the heating of the vehicle interior.

[0023] An air mix damper 28 is provided in the air flow passage 3 on the air upstream side of the condenser 4 to adjust the ratio of air (indoor air or outdoor air) that flows into the air flow passage 3 and passes through the evaporator 9 to the condenser 4 and the auxiliary heater 23.

[0024] <Temperature adjustment unit> In addition to the air conditioning unit 60 as described above, the vehicle air conditioning device 1 further includes a temperature adjustment unit (equipment temperature adjustment circuit) 61 for circulating a heat medium through heat-generating equipment (such as the battery 55 or the motor unit 65) that is the temperature-controlled equipment, thereby adjusting the temperature of the temperature-controlled equipment.

[0025] The temperature adjustment unit 61 is a heat medium circuit configured to be thermally connectable to at least one of a heat radiation unit (condenser 4) or a heat absorption unit (evaporator 9). The motor unit 65 also includes heat-generating devices such as an electric motor for driving the vehicle and an inverter circuit that drives the electric motor. The devices to be temperature-controlled are not limited to the battery 55 and motor unit 65, but can also include other heat-generating devices mounted on the vehicle.

[0026] The temperature adjustment unit 61 includes a first circulation pump 62 and a second circulation pump 63 as circulation devices for circulating the heat medium to the battery 55 and the motor unit 65, a refrigerant-heat medium heat exchanger (hereinafter referred to as a "chiller heat exchanger") 64, a heat medium heater 66, an air-heat medium heat exchanger 67, a three-way valve 81 as a flow path switching device, and a heat storage tank 85.

[0027] The temperature adjustment unit 61 is configured to be connectable to the refrigerant circuit R via the chiller heat exchanger 64. In the refrigerant circuit R, one end of a branch pipe 72 serving as a branch circuit is connected between the connection point of the refrigerant pipe 13A with the refrigerant pipe 13G and the indoor expansion valve 8, and the other end of the branch pipe 72 is connected to the refrigerant flow path of the chiller heat exchanger 64. An auxiliary expansion valve 73 is provided in the branch pipe 72. The auxiliary expansion valve 73 reduces the pressure and expands the refrigerant flowing into the refrigerant flow path of the chiller heat exchanger 64, and can also be fully closed.

[0028] One end of a refrigerant pipe 74 is connected to the outlet of the refrigerant flow path of the chiller heat exchanger 64, and the other end of the refrigerant pipe 74 is connected to the refrigerant pipe 13B between the check valve 20 and the accumulator 12. The chiller heat exchanger 64 constitutes part of the refrigerant circuit R and also constitutes part of the temperature adjustment unit 61.

[0029] One end of the heat medium pipe 68A is connected to the heat medium discharge side of the chiller heat exchanger 64. The heat medium pipe 68A is provided with, in order from the chiller heat exchanger 64 side, a heat medium heater 66, a battery 55, a first circulation pump 62, and a check valve 82. The other end of the heat medium pipe 68A is connected to a heat medium pipe 68B, which will be described later. The heat medium pipe 68A branches off into a heat medium pipe 68B at a position closer to the chiller heat exchanger 64 than the heat medium heater 66. The other end of the branched heat medium pipe 68B is connected to the heat medium inlet of the chiller heat exchanger 64. The heat medium pipe 68B is provided with an air-heat medium heat exchanger 67. The air-heat medium heat exchanger 67 is arranged on the downwind side of the outdoor heat exchanger 7 with respect to the flow (air path) of outside air (air) ventilated by an outdoor fan (not shown).

[0030] A three-way valve 81 is provided on the heat medium pipe 68B downstream of the air-heat medium heat exchanger 67, and the other end of the heat medium pipe 68A is connected between the three-way valve 81 of the heat medium pipe 68B and the heat medium inlet of the chiller heat exchanger 64. A heat storage tank 85 is connected between the connection point between the other end of the heat medium pipe 68A and the heat medium pipe 68B and the heat medium inlet of the chiller heat exchanger 64. The heat medium pipe 68B branches into a heat medium pipe 68C on the heat medium upstream side of the air-heat medium heat exchanger 67 of the heat medium pipe 68B, and the other end of the branched heat medium pipe 68C is connected to the three-way valve 81. A second circulation pump 63 and a motor unit 65 are provided on the heat medium pipe 68C.

[0031] The heat medium used in the temperature adjustment unit 61 can be, for example, water, a refrigerant such as HFO-1234yf, a liquid such as a coolant, or a gas such as air. In this embodiment, water is used as the heat medium, for example. In addition, a jacket structure is provided around the battery 55 and the motor unit 65, which allows the heat medium to circulate in a heat exchange relationship with the battery 55 and the motor unit 65.

[0032] When the first circulation pump 62 is operated, the heat medium discharged from the first circulation pump 62 flows in this order: heat medium pipe 68A, check valve 82, heat medium pipe 68B, heat storage tank 85, the heat medium flow path of the chiller heat exchanger 64, heat medium pipe 68A, heat medium heater 66, and battery 55, before being drawn into the first circulation pump 62. In this flow path control state, the heat medium circulates between the battery 55, heat storage tank 85, and chiller heat exchanger 64. Furthermore, when the three-way valve 81 is switched to a state in which the inlet communicates with the outlet on the chiller heat exchanger 64 side, and the second circulation pump 63 is operated, the heat medium discharged from the second circulation pump 63 flows in this order: heat medium pipe 64C, motor unit 65, three-way valve 81, heat medium pipe 68B, heat storage tank 85, the heat medium flow path of the chiller heat exchanger 64, and heat medium pipe 68B, before being drawn into the second circulation pump 63. In this flow path control state, the heat medium is circulated among the motor unit 65, the heat storage tank 85, and the chiller heat exchanger 64. The heat storage tank 85 absorbs heat from the heat medium circulating in the temperature adjustment unit 61 and is capable of storing heat.

[0033] When the auxiliary expansion valve 73 is open, some or all of the refrigerant flowing out from the refrigerant pipe 13G or the outdoor heat exchanger 7 flows into the branch pipe 72, is decompressed by the auxiliary expansion valve 73, and then flows into the refrigerant flow path of the chiller heat exchanger 64 and evaporates. As the refrigerant flows through the refrigerant flow path of the chiller heat exchanger 64, it absorbs heat from the heat medium flowing through the heat medium flow path, and then passes through the accumulator 12 and is drawn into the compressor 2.

[0034] 2 shows an outline of the hardware configuration of the control device 32 that controls the thermal management system 100 (vehicle air conditioning device 1). Note that Fig. 2 shows only the main components for explaining the thermal management system 100 of this embodiment, and the hardware configuration of the control device 32 includes known components other than those shown in the figure, but these are not shown.

[0035] When the vehicle air conditioning device 1 is mounted on a vehicle, the control device 32 is connected via a vehicle communication bus to a vehicle controller (vehicle ECU (Electronic Control Unit)) 35 that controls the overall vehicle, including drive control of the motor unit 65 and charge / discharge control of the battery 55, and transmits and receives information to and from the vehicle via an in-vehicle network such as a CAN (Controller Area Network) or a LIN (Local Interconnect Network).

[0036] The control device 32 of this embodiment includes a processor (or electrical circuit) 321, such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit), a memory 322, such as a ROM (Read Only Memory) or a RAM (Random Access Memory), a non-volatile storage unit 323, such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive), and a communication control unit 324. The CPU 321, memory 322, storage unit 323, and communication control unit 324 are connected to each other via an internal bus so as to be able to communicate with each other. The storage unit 323 stores various programs and data, including a temperature adjustment control program described below.

[0037] The controller 32 is connected to various sensors (detectors) 30 and an air conditioning operation unit 53, and receives their outputs. The various sensors 30 include at least an outside air temperature sensor 57 that detects the temperature of the outside air of the vehicle, a battery temperature sensor 77 that detects the temperature of the battery 55, and a heat medium temperature sensor 76 that detects the temperature of the heat medium that exchanges heat with the battery 55 (heat medium temperature Tw at the inlet or outlet of the chiller heat exchanger 64). Although not shown, other known sensors that can be controlled by the controller 32 are also connected, such as a rotation speed detection sensor that detects the rotation speed of the compressor 2, an evaporator temperature sensor that detects the temperature of the evaporator 9, an HVAC intake temperature sensor that detects the temperature of air drawn into the air flow passage 3 from the intake port 25, an inside air temperature sensor that detects the temperature of the air inside the vehicle cabin (inside air), a discharge temperature sensor that detects the temperature of air blown into the vehicle cabin from the outlet 29, and a discharge pressure sensor that detects the pressure of the refrigerant discharged from the compressor 2. The control device 32 mainly functions as an air conditioning controller that controls the HVAC system 10 , a heat pump controller that controls the refrigerant circuit R, and a temperature control controller that controls the temperature control unit 61 .

[0038] Although not shown in detail, the output of the control device 32 is connected to components that make up the air conditioning unit 60, such as the compressor 2, outdoor expansion valve 6, indoor expansion valve 8, outdoor blower 7, and HVAC system 10. Also, although not shown in detail, the output of the control device 32 is connected to components that make up the temperature adjustment unit (equipment temperature adjustment circuit) 61, such as a first circulation pump 62, a second circulation pump 63, and a chiller heat exchanger 64.

[0039] The control device 32 controls the vehicle's interior air conditioning (e.g., HVAC system 10) and the refrigerant circuit R based on the outputs of the various sensors 30, values ​​input by the air conditioning operation unit 53, information from the vehicle ECU 35, etc., and controls the temperature adjustment unit 61. Hereinafter, in this embodiment, cooling control of the battery 55 will be mainly described as an example of temperature adjustment control of the temperature adjustment unit 61 by the control device 32.

[0040] The vehicle air conditioning device 1 can select and execute an optimal air conditioning operation mode from multiple air conditioning operation modes depending on the environment in which the vehicle equipped with the vehicle air conditioning device 1 is traveling and the vehicle's condition. For example, by operating a heat pump using the refrigerant circuit R, it is possible to perform air conditioning in the vehicle cabin and temperature control of the battery 55 by switching between various operation modes, such as an air conditioning only mode (heating mode, dehumidifying heating mode, dehumidifying cooling mode, cooling mode, defrosting mode, etc.), an air conditioning priority + battery cooling mode, and a battery cooling priority + air conditioning operation mode. Detailed operations of the air conditioning unit 60 and the temperature control unit 61 in each operation mode are known and will not be described here. The air conditioning only mode is a mode in which only the air conditioning operation in the vehicle cabin is performed without temperature control (cooling) of the battery 55. The "air conditioning priority + battery cooling" mode is a mode in which the temperature control (cooling) of the battery 55 is performed while giving priority to air conditioning operation in the vehicle cabin. The "battery cooling priority + air conditioning" mode is a mode in which temperature regulation (cooling) of the battery 55 is given priority while air conditioning is performed inside the vehicle cabin.

[0041] 3 is a functional block diagram showing an example of the functions of the control device 32 in this embodiment. The control device 32 executes a temperature adjustment control program stored in a storage unit 323 to control the temperature adjustment unit 61. More specifically, the control device 32 functions as a battery temperature controller that adjusts the temperature of the battery 55. FIG. 3 is a functional block diagram of the battery temperature controller, and in this case, the control device 32 includes, for example, a status acquisition unit 325, a temperature information management unit 326, an estimation unit 327, an operating condition correction unit 328, and a temperature adjustment execution unit 329.

[0042] The status acquisition unit 325 constantly acquires the vehicle status and the outside air temperature at a predetermined cycle. The vehicle status specifically includes the connection status with an external power source (whether or not the vehicle is receiving power from the external power source and charging), the operating status of the air conditioning unit 60 (whether the air conditioning is on or off), etc. The status acquisition unit 325 acquires the connection status with the external power source based on information from the vehicle ECU 35, acquires the operating status of the air conditioning unit 60 based on information from the control device 32 serving as an air conditioning controller, and acquires the outside air temperature as a detection result of the outside air temperature sensor 57.

[0043] The temperature information management unit 326 acquires temperature change information (hereinafter referred to as "battery temperature change information") for a predetermined period (temperature change recording period tm) while the battery 55 is being charged, and stores the information in the memory unit 323. The temperature information management unit 326 also acquires past battery temperature change information stored in the memory unit 323. Here, "while the battery 55 is being charged" refers to the period from the point when the battery 55 is connected to an external power source after the vehicle has stopped driving and charging has started (charging start time) until charging is completed.

[0044] The battery temperature change information will be described with reference to Fig. 4. Fig. 4 is a conceptual diagram showing the temperature control of the battery 55 by the temperature adjustment unit 61, in which the vertical axis represents the temperature of the battery 55 and the horizontal axis represents the elapsed time t from the start of charging. Note that, as an example, the temperature of the battery 55 is shown as the temperature Tw of the heat medium that cools the battery 55.

[0045] First, referring to FIG. 4A , as a basic operation of the temperature adjustment (cooling) control of the battery 55 by the temperature adjustment unit 61, the control device 32 sets a temperature control range (hereinafter referred to as the “base temperature control range”) that serves as a reference (initial value) for the optimum operating temperature of the battery 55 and a battery lower limit temperature TwLL (stored in the memory unit 323), and performs temperature adjustment so that the heat medium temperature Tw for cooling the battery 55 falls within the base temperature control range (base temperature lower limit value TwL to base temperature upper limit value TwU) indicated by the dashed-dotted line in FIG. 4 . For example, the base temperature control range has a base temperature lower limit value TwL of 20° C. and a base temperature upper limit value TwU of 30° C. Furthermore, the battery lower limit temperature TwLL is, for example, 15° C. The battery lower limit temperature TwLL is a temperature lower than the battery lower limit temperature TwLL, and is a lower limit value below which the temperature is prohibited in consideration of, for example, deterioration of battery performance due to low temperatures.

[0046] 1 is closed, and if the heat medium temperature Tw increases due to heat generation by the battery 55 or the like and exceeds the base temperature upper limit value TwU, the control device 32 opens the auxiliary expansion valve 73. As a result, the refrigerant flows into the refrigerant flow path of the chiller heat exchanger 64 and evaporates, cooling the heat medium flowing through the heat medium flow path of the chiller heat exchanger 64, and the cooled heat medium cools the battery 55.

[0047] On the other hand, even when the vehicle is stopped (motor power supply is stopped, power is turned off, and the system is stopped) and connected to an external power source, the battery 55 generates heat due to the supply of power from the external power source, so temperature control of the battery 55 is performed even during charging. Specifically, cooling is performed by the temperature control unit 61 so that the temperature does not exceed a predetermined temperature even during charging.

[0048] As described above, in this embodiment, the temperature information management unit 326 acquires, as battery temperature change information, a temperature increase due to heat generation of the battery 55 or a temperature decrease due to cooling of the battery 55 during a temperature change recording period tm while the battery 55 is being charged, and stores the acquired information in the storage unit 323. The temperature change recording period tm is, for example, a period from the start of charging (t=0) until the heat medium temperature Tw reaches the first base temperature lower limit TwL (or the first base temperature upper limit TwU) (tm1 shown in FIG. 4 ). Alternatively, the temperature change recording period tm is a period required for the heat medium temperature Tw to increase from the base temperature lower limit TwL to the base temperature upper limit TwU while the battery 55 is being charged (a period required for the temperature to decrease from the base temperature upper limit TwU to the base temperature lower limit TwL). The battery temperature change information is information indicating a change (temperature increase or decrease) in the heat medium temperature Tw during the temperature change recording period tm.

[0049] The temperature information management unit 326 of this embodiment acquires battery temperature change information during the temperature change recording period tm when the battery 55 is being charged and the air conditioning unit 60 is not operating (the period when the air conditioning is stopped (off)) and stores (accumulates) the information in the memory unit 323.

[0050] More specifically, the temperature information management unit 326 of this embodiment first acquires the outside air temperature at the start of charging (when the external power supply is switched from a disconnected state to a connected state) via the status acquisition unit 325. Then, during a temperature change recording period tm at that outside air temperature, the temperature of the battery 55 (here, the heat medium temperature Tw) is acquired at a predetermined cycle. For example, if the temperature change recording period tm is the period (tm1) from the start of charging (t=0) to the first time the heat medium temperature Tw reaches the base temperature lower limit TwL, in the example shown in FIG. 4A , the temperature decrease (temperature decrease rate) of the heat medium temperature Tw is acquired as the current battery temperature change information.

[0051] The temperature information management unit 326 stores this battery temperature change information as the battery temperature change during the period when the battery 55 is being charged and air conditioning is stopped (hereinafter referred to as the "air-conditioning-stopped-during-charging period") in the memory unit 323 together with the outside air temperature at the start of charging. By repeating this process, the memory unit 323 stores and accumulates battery temperature change information during the air-conditioning-stopped-during-charging period from a certain point in the past to the present for each outside air temperature (using the outside air temperature as a key).

[0052] The temperature information management unit 326 can acquire (past) battery temperature change information using an outside air temperature in a similar range as a key based on the outside air temperature at the start of charging acquired by the status acquisition unit 325 if that information is stored in the memory unit 323.

[0053] In this example, a case is described in which a change in the heat medium temperature Tw that cools the battery 55, which is detected by the heat medium temperature sensor 76, is acquired as the temperature change of the battery 55. However, the temperature change of the battery 55, which is detected by the battery temperature sensor 77, may be acquired directly. Alternatively, the temperature change of the battery 55 may be estimated from the change in the heat medium temperature Tw detected by the heat medium temperature sensor 76 and acquired.

[0054] Based on the battery temperature change information, the estimation unit 327 estimates the degree of deterioration of the battery 55. Specifically, the estimation unit 327 estimates the degree of deterioration (deterioration level) of the current battery 55 by comparing it with when the vehicle was new or with a certain point in the past (for example, one year ago, three years ago, etc.).

[0055] An example of a method for estimating the deterioration level of the battery 55 by the estimation unit 327 will be described with reference to FIG. 4B . FIG. 4B is a conceptual diagram illustrating temperature control of the battery 55 by the temperature adjustment unit 61, similar to FIG. 4A , and is a graph showing two sets of battery temperature change information stored (recorded) at different times in the storage unit 323 by the temperature information management unit 326. The solid line represents the current (latest) battery temperature change information (current battery temperature change information) at a certain outside temperature (e.g., 25° C.), and the dashed line represents the past (e.g., five years ago) battery temperature change information (past battery temperature change information) at the same outside temperature (25° C.). In this example, the temperature change recording period tm is set to the period (tm1) from the start of charging (t=0) to the time when the heat medium temperature Tw first reaches the base temperature lower limit value TwL.

[0056] When temperature control of the battery 55 is being performed, the heat medium temperature Tw fluctuates within the base temperature control range. However, if the outside air temperature is approximately the same, the heat medium temperature Tw at that outside air temperature can be determined to be approximately the same. On the other hand, as the battery 55 deteriorates, the internal resistance of the battery 55 increases, increasing the amount of heat generated per unit time. This increases the temperature increase rate until the heat medium temperature Tw reaches the base temperature upper limit value TwU, while decreasing the temperature decrease rate until the heat medium temperature Tw reaches the base temperature lower limit value TwL. The estimation unit 327 estimates that the battery 55 has deteriorated when the temperature change rate (in this example, the temperature decrease rate) of the current battery temperature change information has fluctuated (decreased) by more than a threshold value (e.g., 10%) compared with the past battery temperature change information stored in the storage unit 323. Alternatively, when the temperature increase rate of the current battery temperature change information has increased by more than a threshold value (e.g., 10%) compared with the past battery temperature change information, the estimation unit 327 estimates that the battery 55 has deteriorated.

[0057] In this way, the estimation unit 327 estimates that the current battery 55 is "degraded" if the level of degradation is significant (above a certain threshold) when the past capacity of the battery 55 is used as a reference (the same applies below).

[0058] Alternatively, it can be said that as deterioration of the battery 55 progresses, the time from when the heat medium temperature Tw reaches the base temperature upper limit value TwU until when it reaches the base temperature lower limit value TwL becomes longer, and the time from when the heat medium temperature Tw reaches the base temperature lower limit value TwL until it reaches the base temperature upper limit value TwU becomes shorter. Therefore, the temperature change recording period tm may be set to the period (tm2) from the base temperature upper limit value TwU to the base temperature lower limit value TwL, and the estimation unit 327 may estimate that the battery 55 has deteriorated if the temperature change recording period tm2 of the current battery temperature change information is longer than the temperature change recording period tm2 of the past battery temperature change information at a similar past outside air temperature, or if the temperature change recording period tm is set to the period (tm2) from the base temperature lower limit value TwL to the base temperature upper limit value TwU and the temperature change recording period tm2 of the current battery temperature change information is shorter than the temperature change recording period tm2 of the past battery temperature change information at a similar past outside air temperature.

[0059] In this embodiment, the period for acquiring battery temperature change information is the period during which the vehicle is being charged from an external power source and during which the air conditioning is stopped. This is because, when the air conditioning is running, the air conditioning load changes depending on the outside temperature and the number of occupants, and the state of the battery 55 frequently changes depending on various controls while the vehicle is running or when charging is complete. Therefore, during the period during which the vehicle is being charged and the air conditioning is stopped, relatively stable temperature information of the battery 55 corresponding to the outside temperature (with little variation due to the operation of other devices) can be acquired. By doing this, even if information regarding the deterioration of the battery 55 cannot be acquired from the vehicle ECU 35, the control device 32 of the thermal management system 100 can determine the deterioration state of the battery 55 and then adjust the temperature of the battery 55. Furthermore, the error in determining the deterioration state of the battery 55 can be reduced. As a result, the progression of deterioration of the battery 55 can be suppressed.

[0060] 4 shows a case where the heat medium temperature Tw is within the base temperature control range at the start of charging (t=0) while charging is in progress, such as after returning home, and the air conditioning is stopped. However, because the timing at which charging is started is arbitrary (for example, charging before getting into the car, charging at a charging station while traveling, etc.), there may be situations in which the temperature is outside the base temperature control range at the start of charging. Even in such cases, the method for estimating the degradation level of the battery 55 is the same as that described above.

[0061] FIG. 4 also illustrates, as an example, a case in which control is performed to start cooling the battery 55 while the air conditioning is stopped during charging, i.e., the control device 32 issues a command to cool the battery 55, causing the heat medium temperature Tw to decrease from the start of charging. However, this is not limiting. Alternatively, the battery 55 may not be cooled at the start of charging, but may be allowed to self-heat. In this case, the start point of cooling the battery 55 is controlled based on whether or not a cooling start flag is set. For example, if the heat medium temperature Tw is equal to or lower than the base temperature upper limit TwU at the start of charging (t=0) and the cooling start flag is not set, the heat medium temperature Tw increases over time from the start of charging, resulting in the temperature change shown in FIG. 4 being reversed. If the heat medium temperature Tw is equal to or lower than the base temperature upper limit TwU at the start of charging (t=0) and the cooling start flag is set, the temperature change will be similar to that shown in FIG. 4.

[0062] The operating condition correcting unit 328 corrects the operating conditions of the temperature adjusting unit 61 based on the estimation result of the estimating unit 327, specifically when it is estimated that the battery 55 has deteriorated to a considerable extent (a certain threshold or more). The operating conditions of the temperature adjusting unit 61 are, for example, the base temperature management range or the timing to start cooling the battery 55. If the amount of heat generated per unit time increases due to deterioration of the battery 55, the rate of temperature rise increases, and there is a possibility that the heat medium temperature Tw will exceed the base temperature upper limit value TwU even if temperature adjustment is being performed.

[0063] Specifically, the correction of the operating conditions will be described with reference to Fig. 5. Fig. 5 is a conceptual diagram showing an example of the operating conditions (base temperature control range) of the temperature adjustment unit 61 and air conditioning operation, in which the vertical axis represents the temperature of the battery 55 (heat medium temperature Tw) and the horizontal axis represents the elapsed time t from the start of charging.

[0064] In temperature control when the estimation unit 327 determines that the battery 55 is not degraded (or is considerably degraded), the base temperature management range of the battery 55 is set as an initial value (reference value), for example, between a base temperature lower limit value TwL (e.g., 20°C) and a base temperature upper limit value TwU (e.g., 30°C), as indicated by the dashed line. In this case, the control device 32 starts cooling the battery 55 by setting a cooling start flag that starts cooling the battery 55 after the temperature of the battery 55 (here, the heat medium temperature Tw) rises to the base temperature upper limit value TwU of 30°C. Even under these conditions, if there is no degradation of the battery 55, cooling of the battery 55 can actually start before the temperature exceeds 30°C. In contrast, if the estimation unit 327 determines that the battery 55 is degraded, setting the cooling start flag for the battery 55 after the temperature rises to the base temperature upper limit value TwU of 30°C is likely to exceed 30°C before cooling of the battery 55 actually begins. If this happens, the base temperature control range may be exceeded many times during use of the battery 55, which may accelerate deterioration of the battery 55.

[0065] In such a case, the operating condition corrector 328 corrects the temperature threshold (cooling start target temperature) at which cooling of the battery 55 is started, i.e., the base temperature upper limit value TwU of the base temperature management range, lowering it from the current value to, for example, 29°C. As a result, the base temperature management range becomes the base temperature lower limit value TwL to the base temperature upper limit value TwU', which is narrower than when it is estimated that the battery 55 is not degraded. The amount of correction made by the operating condition corrector 328 in one operation is set to an arbitrary predetermined value, such as -1°C, depending on the estimated level of degradation.

[0066] After the driving conditions are corrected by the driving condition correction unit 328, the temperature of the battery 55 is controlled under the corrected driving conditions both during charging and when the vehicle is started (for example, when driving, the motor is energized, the power is on, the system is started, etc., the same applies below).

[0067] Alternatively, if it is estimated that the battery 55 is degraded, the operating condition correction unit 328 corrects the timing for setting the cooling start flag for the battery 55, i.e., the cooling start timing for the battery 55, to be earlier than the currently set timing.

[0068] By doing this, even when the battery 55 is used at maximum heat generation when it is estimated to be deteriorated, the temperature of the battery 55 can be reliably kept within the base temperature control range, or the temperature rise of the battery 55 can be made gradual, thereby suppressing the progression of deterioration of the battery 55.

[0069] The temperature adjustment execution unit 329 performs temperature adjustment based on the operating conditions set by the temperature adjustment unit 61. Specifically, if the operating conditions have been corrected by the operating condition correction unit 328, the temperature adjustment execution unit 329 notifies the vehicle ECU 35 of the corrected operating conditions, and performs temperature adjustment under the corrected operating conditions if the vehicle ECU 35 permits the correction. If the operating conditions have not been corrected, or if the vehicle ECU 35 does not permit the correction, the temperature adjustment is performed under the current (pre-correction) operating conditions.

[0070] Furthermore, the temperature adjustment execution unit 329 performs air conditioning operation mode switching control to switch between an air conditioning only mode, an "air conditioning priority + battery cooling" mode, and a "battery cooling priority + air conditioning" mode during air conditioning operation while the vehicle is starting. In particular, if the estimation unit 327 estimates that the battery 55 is degraded, it is possible to switch the priority between temperature adjustment and air conditioning.

[0071] Continuing with reference to FIG. 5 , an example of air-conditioning operation mode switching control will be described. FIG. 5A is a conceptual diagram showing an example of air-conditioning operation mode switching control when the estimation unit 327 estimates that there is no degradation of the battery 55, or when the degradation of the battery 55 is estimated but the degree of degradation is relatively low. FIG. 5B is a conceptual diagram showing an example of air-conditioning operation mode switching control when the estimation unit 327 estimates that there is degradation of the battery 55 and the degree of degradation is high. In both diagrams, the vertical axis represents heat medium temperature Tw and the horizontal axis represents time t. Also, in FIG. 5 , it is assumed that the operating condition correction unit 328 corrects the base temperature control range and that permission for the correction has been obtained from the vehicle ECU 35. That is, the upper limit value of the base temperature control range shown in FIG. 5 is lowered from the base temperature upper limit value TwU before correction to the base temperature upper limit value TwU′ after correction.

[0072] Referring to FIG. 5A , a case will be described in which, for example, it is estimated that the battery 55 is degraded, but the degree of degradation is (actually) relatively low. In this case, from the start of air conditioning operation until time t1, the temperature adjustment execution unit 329 performs air conditioning operation in air conditioning only mode. Then, when the temperature of the battery 55 (here, the heat medium temperature Tw) reaches the base temperature upper limit value TwU′ at time t1, the temperature adjustment execution unit 329 switches from the air conditioning only mode to the “air conditioning priority + battery cooling” mode. If the degree of degradation of the battery 55 is relatively low, air conditioning operation in the “air conditioning priority + battery cooling” mode can sufficiently cool the battery 55 and keep the heat medium temperature Tw within the base temperature management range. If it is estimated that the battery 55 is not degraded, the operation is similar except that the base temperature management range is the range before correction (the upper limit value is the base temperature upper limit value TwU).

[0073] In contrast, if the degree of deterioration of the battery 55 is more advanced (if the degree of deterioration of the battery 55 is large), the capacity of the battery 55 is used for air conditioning in air conditioning operation in the "air conditioning priority + battery cooling" mode, so the temperature drop in the battery 55 is slow even if the battery 55 is cooled. Therefore, after correcting the base temperature management range (from the base temperature upper limit value TwU to the corrected base temperature upper limit value TwU'), if the rate of temperature drop falls below a certain standard, the mode is switched from the "air conditioning priority + battery cooling" mode to the "battery cooling priority + air conditioning" mode.

[0074] 5B , from the start of air conditioning operation until time t2, the temperature adjustment execution unit 329 performs air conditioning operation in air conditioning only mode. Then, when the temperature of the battery 55 (here, the heat medium temperature Tw) reaches the base temperature upper limit value TwU' at time t2, the temperature adjustment execution unit 329 switches from the air conditioning only mode to the "air conditioning priority + battery cooling" mode. If the heat medium temperature Tw does not fall to the threshold temperature Twth by time t3, which is a predetermined period after the base temperature upper limit value TwU' is reached, the temperature adjustment execution unit 329 switches from the "air conditioning priority + battery cooling" mode to the "battery cooling priority + air conditioning" mode at that time (time t3).

[0075] In this way, when the deterioration level of the battery 55 is relatively low, the cooling capacity of the refrigerant circuit R is set to the "air conditioning priority + battery cooling" mode, and when the deterioration level of the battery 55 becomes relatively high, the cooling capacity is switched to "battery cooling priority + air conditioning." This makes it possible to suppress the progression of deterioration of the battery 55, suppress a decrease in cruising range due to the temperature of the battery 55 not being able to be maintained within an appropriate range during use, and extend the life of the battery 55.

[0076] Note that the example in Figure 5 illustrates a case where the base temperature management range (base temperature upper limit value TwU) is corrected, i.e., a case where the correction is permitted by the vehicle ECU 35. However, the above-mentioned air conditioning operation mode switching control is applicable even when the vehicle ECU does not permit correction of the base temperature management range (base temperature upper limit value TwU).

[0077] <Temperature Control Process> An example of the temperature control process in the thermal management system 100 of this embodiment will now be described. Figures 6 and 7 are flow charts showing an example of the flow of the temperature control process. The control device 32 executes a temperature control program stored in the storage unit 323 to perform the temperature control process. The flow charts shown in Figures 6 and 7 show a flow when the temperature control process mainly includes battery cooling processing. Furthermore, the temperature control process shown in Figures 6 and 7 is always executed at a predetermined cycle, regardless of whether the vehicle is started, stopped, or charging.

[0078] First, in step S01, the vehicle status is acquired by the status acquisition unit 325. The status acquisition unit 325 constantly acquires the vehicle status at a predetermined cycle, independent of the temperature adjustment control process. Examples of the vehicle status acquired include the connection status between the vehicle and an external power source (charging start (external power source connection start), charging in progress, charging completed (external power source not connected)), the vehicle start status, and the vehicle running status, based on information from the vehicle ECU 35. Furthermore, whether the air conditioning unit 60 is operating or stopped is acquired based on information from the air conditioning controller of the control device 32. Furthermore, the outside air temperature is acquired as a result of detection by the outside air temperature sensor 57, and the heat medium temperature Tw is acquired as a result of detection by the heat medium temperature sensor 76.

[0079] In the next step S03, it is determined whether charging has started, i.e., whether the state has changed from not being connected to an external power source (before charging started) to being connected to an external power source (charging started). If charging has started, the latest outside air temperature (outside air temperature at the start of charging) acquired by the status acquisition unit 325 is stored in a predetermined area of ​​the memory unit 323, and the process proceeds to step S05. If charging has not started in step S03 (if charging is in progress except at the start of charging, if charging is complete (not connected to an external power source), or if the vehicle is traveling), the process proceeds to step S19. In step S19, the temperature adjustment execution unit 329 executes temperature adjustment, which will be described later.

[0080] In step S05, it is determined whether the operation state of the air conditioning unit 60 is stopped, and if it is stopped, the process proceeds to step S07, and if it is operating, the process proceeds to step S19. In step S07, it is determined whether the temperature change recording period tm has elapsed after charging started, and if the temperature change recording period tm has not elapsed, the process proceeds to step S09, and if the temperature change recording period tm has elapsed, the process proceeds to step S11.

[0081] In step S09, the temperature information management unit 326 stores the latest temperature of the battery 55 (heat medium temperature Tw) acquired by the status acquisition unit 325 in a predetermined area of ​​the storage unit 323. Here, the temperature change recording period tm is set to, for example, the period from the start of charging to the most recent base temperature lower limit value TwL (see FIG. 4B).

[0082] Steps S07 to S09 are repeated, and the temperature information management unit 326 links the multiple heat medium temperatures Tw acquired during the temperature change recording period tm to the outside air temperature at the start of charging (using the outside air temperature at the start of charging as a key), and stores the linked heat medium temperatures Tw as current battery temperature change information in a predetermined area of ​​the memory unit 323.

[0083] In step S11, it is determined whether past battery temperature change information including an outside air temperature (a±x°C) that is close to the outside air temperature a°C included in the current battery temperature change information stored in the memory unit 323 is stored in the memory unit 323. If past battery temperature change information is stored, the temperature information management unit 326 acquires the past battery temperature change information and the process proceeds to step S13. If past battery temperature change information is not stored in the memory unit 323, the process proceeds to step S17, where the current battery temperature change information is stored in a predetermined area of ​​the memory unit 323, and the process returns to step S01.

[0084] In step S13, which is performed when there is past battery temperature change information, the degree of deterioration of the battery 55 is determined. That is, the estimation unit 327 compares the past battery temperature change information, which includes an outside air temperature (a° C.) that is close to the outside air temperature (a±x° C.) included in the current battery temperature change information, to estimate the degree of deterioration of the battery 55. For example, as shown in FIG. 4B , the estimation unit 327 compares the past battery temperature change information with the current battery temperature change information, and if, for example, the temperature decrease rate in the current battery temperature change information is smaller than the temperature decrease rate in the past battery temperature change information (e.g., if the temperature has decreased by more than a threshold value (e.g., 10%)), the estimation unit 327 estimates that the battery 55 is deteriorated, and proceeds to step S15; otherwise, the estimation unit 327 estimates that the battery 55 is not deteriorated, and returns to step S01.

[0085] In step S15, the operating condition corrector 328 corrects the operating conditions for the temperature adjuster 61, and the process returns to step S01. Specifically, the operating condition corrector 328 narrows the base temperature control range (lowers the base temperature upper limit value TwU) or advances the cooling start timing.

[0086] Fig. 7 is a flow diagram showing an example of the flow of the temperature adjustment execution process in step S19 of the temperature adjustment control process shown in Fig. 6. The temperature adjustment execution process is executed during charging other than at the start of charging, after charging is completed (when an external power source is not connected), while the vehicle is starting, while the vehicle is running, etc.

[0087] In step S21, it is determined whether the operating conditions for the temperature adjustment unit 61 have been corrected by the operating condition correction unit 328. If the operating conditions have been corrected, the process proceeds to step S23. If the operating conditions have not been corrected, the process proceeds to step S33. In step S33, the temperature adjustment execution unit 329 executes battery cooling control under normal (initial setting) operating conditions (previous operating conditions without any correction of the operating conditions for the temperature adjustment unit 61). The normal battery cooling control is the same as the basic operation of the temperature adjustment (cooling) control of the battery 55 by the temperature adjustment unit 61 described with reference to FIG. 4A, and therefore a description thereof will be omitted.

[0088] In step S23, the driving condition correction unit 328 notifies the vehicle ECU 35 that the driving conditions will be corrected, and the process proceeds to step S25. In step S25, it is determined whether or not the vehicle ECU 35 has given permission to correct the driving conditions. If permission to correct the driving conditions has been given, the process proceeds to step S27, and if permission to correct the driving conditions has not been given, the process proceeds to step S33.

[0089] In step S27, the temperature adjustment execution unit 329 performs battery cooling control based on the corrected operating conditions. The battery cooling control based on the corrected operating conditions is the same as normal battery cooling control except that the base temperature management range is narrowed in this example, so a description thereof will be omitted.

[0090] Furthermore, in step S29, the temperature adjustment execution unit 329 determines whether or not switching of the air conditioning operation mode is necessary. If switching of the air conditioning operation mode is necessary, the process proceeds to step S31. If not, the process returns to step S01. The determination of switching of the air conditioning operation mode in step S29 is, for example, a determination to switch from the "air conditioning priority + battery cooling" mode to the "battery cooling priority + air conditioning" mode in accordance with the degree of deterioration of the battery 55 when the air conditioning operation is performed by switching between the air conditioning only mode and the "air conditioning priority + battery cooling" mode during start-up of the vehicle (e.g., while the vehicle is running). Specifically, in step S31, it is determined whether or not the degree of deterioration of the battery 55 is large and the temperature decrease rate is below a certain standard (e.g., whether or not the temperature decreases to a predetermined heat medium temperature Tw within a predetermined time) (see FIG. 5B ). If the temperature decrease rate is below the certain standard, the "air conditioning priority + battery cooling" mode is switched from the "air conditioning priority + battery cooling" mode to the "battery cooling priority + air conditioning" mode.

[0091] The determination of switching the air conditioning operation mode and the air conditioning operation mode switching control in steps S29 and S31 may not be executed.

[0092] As described above, in this embodiment, the degree of deterioration of the battery 55 is estimated using information about the battery 55 acquired during charging (while power is being supplied from an external power source). When the vehicle is started, requests from other on-board devices, such as the air conditioning unit 60, can cause large variations in measurement data indicating the performance of the battery 55 (such as internal resistance, heat generation, and heat medium temperature Tw). Even if the deterioration state (deterioration level) of the battery 55 is estimated based on these data, the accuracy of the estimation is poor. According to this embodiment, the variation in measurement data indicating the performance of the battery 55 (such as heat medium temperature Tw) due to requests from other on-board devices, such as the air conditioning unit 60, can be reduced, thereby improving the accuracy of the estimation of the deterioration state of the battery 55. As a result, the temperature of the battery 55 can be more accurately adjusted in accordance with the deterioration state of the battery 55, thereby effectively suppressing the progression of deterioration of the battery 55.

[0093] In addition, the degree of deterioration of the battery 55 is estimated using temperature information of the battery 55 obtained while the battery 55 is charging and the air conditioning unit 60 is stopped, so the operating state of the air conditioning unit 60 device can be made more uniform to a certain extent, and the variation in the measurement data indicating the performance of the battery 55 can be further reduced.

[0094] In particular, the degree of deterioration of the battery 55 is estimated using temperature information of the battery 55 detected while the battery 55 is charging and the air conditioning unit 60 is not operating, so that the variation in the measurement data indicating the performance of the battery 55 due to requests from the air conditioning unit 60 device can be further suppressed, and the accuracy of estimating the deterioration state (deterioration level) of the battery 55 can be further improved.

[0095] In addition, the deterioration state of battery 55 is estimated by comparing temperature change information (current battery temperature change information) about battery 55 for a specified period under the current outside air temperature at the start of charging with temperature change information (past battery temperature change information) about battery 55 for a specified period in the past under an outside air temperature that is close to the current outside air temperature, thereby further improving the accuracy of estimating the deterioration state (deterioration level) of battery 55.

[0096] Furthermore, when the estimation unit 327 estimates that the battery 55 is degraded, the control device 32 lowers the target cooling temperature of the battery 55 or corrects the start of cooling earlier, so that even if the amount of heat generated by the battery 55 increases due to degradation, the temperature of the battery 55 can be reliably kept within the base temperature management range or the temperature rise of the battery 55 can be slowed down. As a result, the progression of degradation of the battery 55 can be suppressed.

[0097] Furthermore, when the estimation unit 327 estimates that the battery 55 is degraded, the control device 32 switches the priority of temperature regulation and air conditioning during the start-up of the vehicle (during system operation) depending on the degree of degradation, thereby enabling temperature regulation of the battery 55 without significantly impairing the comfort of the vehicle occupants.

[0098] <Modifications> In the above embodiment, the degree of deterioration of the battery 55 is estimated by comparing current battery temperature change information during charging and when the air conditioning is stopped with past battery temperature change information at similar outside air temperatures. However, this is not limiting. For example, vehicle information (e.g., motor load and air conditioning load) and battery temperature change information for a predetermined period while the ignition is on may be monitored, and the operating conditions for the temperature adjustment unit 61 may be corrected according to the vehicle information to adjust the temperature (cooling) of the battery 55. Furthermore, battery temperature change information for a predetermined period while the vehicle is idling may be monitored, and the operating conditions for the temperature adjustment unit 61 may be appropriately corrected to adjust the temperature (cooling) of the battery 55.

[0099] Furthermore, when the external power source is performing rapid charging, a large amount of current flows in a short period of time, which increases the rate of increase in the temperature (heat medium temperature Tw) of the battery 55 even when the battery 55 is not significantly deteriorated. In the above embodiment, the operating condition correction unit 328 performs a correction to narrow the base temperature management range (to lower the base temperature upper limit value TwU). However, as a result, the risk of exceeding the base temperature upper limit value TwU increases during rapid charging. Therefore, the operating conditions for the temperature adjustment unit 61 may be corrected based on map information and current location information from the vehicle's navigation system so as to advance the timing for starting cooling in the vicinity of a charging spot.

[0100] Furthermore, the rate of increase in the battery temperature change information tends to be steep at points where the motor load increases or where discharge increases due to changes in driving conditions, such as when going uphill or on a highway. In order to suppress deterioration of the battery 55 due to temperature increases at such points, the driving conditions for the temperature adjustment unit 61 may be corrected based on map information and current location information from the navigation system so as to narrow the base temperature control range when going uphill or near a highway entrance.

[0101] The vehicle is not limited to an electric vehicle, but the present invention is also effective for a so-called hybrid vehicle that uses both an engine and a traction motor, and in which the battery 55 can be charged from an external power source (such as a quick charger).

[0102] Furthermore, the thermal management system 100 is not limited to the above example, and can be applied to other circuit (device) configurations as long as they include a temperature adjustment unit 61 capable of cooling the battery 55 .

[0103] As described above, the thermal management system 100 of the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made within the scope of the gist of the present invention.

[0104] REFERENCE SIGNS LIST 1 Vehicle air conditioning device 2 Compressor (electric compressor) 3 Air flow passage 4 Condenser 6 Outdoor expansion valve 7 Outdoor heat exchanger (radiator) 8 Indoor expansion valve 9 Evaporator 10 HVAC system 12 Accumulator 13A to 13H Refrigerant piping 18 Check valve 20 Check valve 21 Solenoid valve 22 Solenoid valve 23 Auxiliary heater 25 Intake port 26 Intake switching damper 27 Indoor blower (blower fan) 28 Air mix damper 29 Outlet 31 Outlet switching damper 32 Control device 35 Vehicle ECU 53 Air conditioning operation unit 55 On-board battery (battery) 57 Outside air temperature sensor 60 Air conditioning unit (air conditioning circuit) 61 Temperature adjustment unit (equipment temperature adjustment circuit) 64 Chiller heat exchanger 65 Motor unit 66 Heat medium heater 67 Heat medium heat exchanger 68A Heat medium piping 68B Heat medium piping 68C Heat medium piping 72 Branch piping 73 Auxiliary expansion valve 74 Refrigerant piping 76 Heat medium temperature sensor 77 Battery temperature sensor 81 Three-way valve 82 Check valve 85 Heat storage tank 100 Thermal management system 321 CPU 322 Memory 323 Storage unit 324 Communication control unit 325 Status acquisition unit 326 Temperature information management unit 327 Estimation unit 328 Operating condition correction unit 329 Temperature adjustment execution unit R Refrigerant circuit Tw Heat medium temperature TwL Base temperature lower limit value TwU Base temperature upper limit value TwLL Battery lower limit temperature Twth Threshold temperature a Outside air temperature t Time t1 Time t2 Time tm Temperature change recording period

Claims

1. A thermal management system having an on-board battery, a temperature adjustment unit that adjusts the temperature of the on-board battery, and a control unit, wherein the control unit has a memory unit that stores information about the on-board battery while it is being charged, and an estimation unit that estimates the degree of deterioration of the on-board battery based on the information, and corrects the operating conditions of the temperature adjustment unit based on the estimation result of the estimation unit.

2. The thermal management system described in claim 1, further comprising an air conditioning unit for conditioning the air inside the vehicle cabin, and the information includes temperature information regarding the vehicle battery when the vehicle battery is being charged from an external power source and the air conditioning unit is not operating.

3. The thermal management system described in claim 2, characterized in that the information includes the outside air temperature during charging and temperature change information regarding the vehicle battery over a specified period of time, and the estimation unit compares the current information with the past information stored in the memory unit to estimate the state of deterioration of the vehicle battery.

4. The thermal management system of claim 1, characterized in that the control device reduces the cooling target temperature of the vehicle battery by the temperature adjustment unit when the estimation unit estimates that the vehicle battery is deteriorated.

5. The thermal management system according to claim 1, characterized in that, when the estimation unit estimates that the vehicle battery is deteriorated, the control device narrows the temperature control range of the vehicle battery by the temperature adjustment unit.

6. The thermal management system according to claim 1, characterized in that, when the estimation unit estimates that the vehicle battery is deteriorated, the control device corrects the timing at which the temperature adjustment unit starts cooling the vehicle battery.

7. The thermal management system of claim 2, characterized in that the control device switches the priority between the temperature control and the air conditioning during vehicle startup when the estimation unit estimates that the on-board battery is degraded.

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