Battery temperature control system

Abstract

The present invention provides a battery temperature control system capable of appropriately predicting battery temperature changes. The battery temperature control system (1) maintains the temperature of the battery (B) mounted on the electric vehicle (V) within a target temperature range during the parking period of the electric vehicle (V). The battery temperature control system (1) includes: an environment estimation unit (21) that estimates the environment in which the electric vehicle (V) is parked; a reference temperature setting unit (22) that sets a reference temperature from multiple temperature information based on the environment estimated by the environment estimation unit (21); a battery temperature change prediction unit (24) that predicts the temperature change of the battery (B) based on the reference temperature; and a battery temperature adjustment unit (25) that adjusts the temperature of the battery (B) based on the temperature change of the battery (B).

Description

Technical Field

[0001] This invention relates to a battery temperature control system. Background Technology

[0002] In recent years, efforts to achieve a low-carbon or decarbonized society have become increasingly active as a concrete countermeasure to global climate change. There is also a strong demand for CO2 emission reductions for vehicles and other mobile vehicles, leading to rapid development in the electrification of power sources. Specifically, the development of vehicles such as electric vehicles or hybrid electric vehicles (HEVs) is underway, featuring an electric motor as the vehicle's power source and a battery as a secondary battery that supplies power to the electric motor.

[0003] If a battery is placed in a high-temperature environment, it may deteriorate and its performance may decrease. Therefore, techniques for cooling batteries are known (e.g., Patent Documents 1-5).

[0004] Furthermore, if the battery is exposed to high temperatures above the specified temperature or low temperatures below the specified temperature while the vehicle is parked, the electric vehicle may not be able to be properly driven when the user wants to use it.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2020-124012

[0008] Patent Document 2: Japanese Patent Application Publication No. 2020-89021

[0009] Patent Document 3: Japanese Patent Application Publication No. 2019-161791

[0010] Patent Document 4: Japanese Patent Application Publication No. 2019-126170

[0011] Patent Document 5: Japanese Patent Application Publication No. 2006-139963 Summary of the Invention

[0012] The problem that the invention aims to solve

[0013] To prevent the battery from being at a high temperature above a specified temperature or a low temperature below a specified temperature while the vehicle is parked, it is necessary to predict and regulate the battery temperature. However, there is still room for research on how to predict battery temperature changes.

[0014] This invention provides a battery temperature control system capable of appropriately predicting battery temperature changes.

[0015] Methods for solving problems

[0016] The battery temperature control system of the present invention maintains the temperature of the battery mounted on the electric vehicle within a target temperature range during the parking period of the electric vehicle. The battery temperature control system comprises:

[0017] An environmental estimation department, which estimates the environment in which the electric vehicle is parked;

[0018] The reference temperature setting unit sets a reference temperature from multiple temperature information based on the environment estimated by the environment estimation unit.

[0019] A battery temperature change prediction unit predicts the temperature change of the battery based on the reference temperature; and

[0020] A battery temperature regulation unit that adjusts the battery temperature based on temperature changes in the battery.

[0021] Invention Effects

[0022] According to the present invention, it is possible to predict battery temperature changes appropriately. Attached Figure Description

[0023] Figure 1 This is a diagram showing electric vehicles V parked inside and outside a building.

[0024] Figure 2 This is a block diagram showing the structure of the battery temperature control system 1.

[0025] Figure 3 This is a flowchart illustrating the environmental estimation process.

[0026] Figure 4 This is a diagram showing the relationship between first sunshine information based on sunshine data and second sunshine information based on sunshine sensors.

[0027] Figure 5 This is an example diagram showing weather forecast information.

[0028] Figure 6 This is a graph showing the relationship between solar radiation and correction values.

[0029] Figure 7 This is a flowchart illustrating an example of a battery temperature control process.

[0030] Figure 8 This is a flowchart illustrating another example of the battery temperature control process.

[0031] Explanation of reference numerals in the attached figures

[0032] 1. Battery Temperature Control System

[0033] 3. External air temperature sensor

[0034] 4 Sunlight Sensor

[0035] 5. Camera (image acquisition device)

[0036] 21 Environmental Presumption Department

[0037] 22 Reference Temperature Setting Section

[0038] 23. Calibration value setting section

[0039] 24 Battery Temperature Change Prediction Department

[0040] 25 Battery Temperature Regulation Section Detailed Implementation

[0041] The following is for reference Figures 1 to 7 One embodiment of the present invention will be described.

[0042] like Figure 1 and Figure 2 As shown, the electric vehicle V includes: an electric motor (not shown) as a drive source; a battery B as a secondary battery that can supply power to the electric motor; and a battery temperature control system 1 that maintains the temperature of the battery B within a target temperature range during the parking period of the electric vehicle V.

[0043] The battery temperature control system 1 predicts the temperature change of battery B during the parking period of electric vehicle V and adjusts the temperature of battery B based on the predicted temperature change. At this time, the battery temperature control system 1 switches the method for predicting the temperature change of battery B according to the parking environment of electric vehicle V. For example, in... Figure 1 The electric vehicle V is parked in an environment shown on the left, inside a building G (e.g., in a private garage, a covered parking lot, etc.) and as shown on the left. Figure 1 As shown on the right, in the case where the electric vehicle V is parked outside the building G (e.g., outdoor parking at home, open parking lot, roadside parking, etc.), different prediction methods are used to predict the temperature change of the battery B. The specific structure of the battery temperature control system 1 will be described below.

[0044] like Figure 2As shown, the battery temperature control system 1 includes a control unit 2 that performs the battery temperature control described later. Connected to the control unit 2 are an external air temperature sensor 3 for detecting external air temperature, a sunlight sensor 4 for detecting sunlight intensity, a camera 5 for capturing images of the outside of the vehicle, a navigation device 6, a vehicle speed sensor 7 for detecting vehicle speed, a communication device 8 capable of communicating with a weather information server 30, and a temperature regulating device 9 for regulating the temperature of battery B. Therefore, the external air temperature is input to the control unit 2 from the external air temperature sensor 3, the sunlight intensity is input to the control unit 2 from the sunlight sensor 4, image data of the outside of the vehicle is input to the control unit 2 from the camera 5, and information related to vehicle speed is input to the control unit 2 from the vehicle speed sensor 7.

[0045] The navigation device 6, for example, includes a GNSS (Global Navigation Satellite System) receiver and a navigation HMI, and stores map information in a storage device such as an HDD (Hard Disk Drive) or flash memory. The GNSS receiver determines the vehicle's position based on signals received from GNSS satellites. The navigation HMI includes a display device, a speaker, a touch panel, buttons, etc. The map information, for example, represents the shape of roads by indicating road segments and nodes connecting these segments. It should be noted that the navigation device can be implemented using the functions of a terminal device such as a smartphone or tablet owned by the user.

[0046] The communication device 8 includes a wireless module for connecting to cellular networks or Wi-Fi networks. The communication device 8 communicates with, for example, a weather information server 30 via a network such as the Internet or Ethernet.

[0047] Temperature control device 9 cools battery B by allowing refrigerant to flow through a refrigerant path provided in battery B. Temperature control device 9 is, for example, water-cooled, using a pump to circulate the refrigerant and a radiator to cool it. It should be noted that temperature control device 9 is equipped with a heater, which can also heat battery B.

[0048] As a functional configuration achieved through the collaboration of hardware and software, the control unit 2 includes an environment estimation unit 21, a reference temperature setting unit 22, a correction value setting unit 23, a battery temperature change prediction unit 24, and a battery temperature adjustment unit 25.

[0049] The environmental estimation section 21 estimates the parking environment of the electric vehicle V. For example, it estimates whether the vehicle is outside or inside a building G based on images of the exterior taken by camera 5. Furthermore, as... Figure 3 and Figure 4As shown, the environmental estimation unit 21 can estimate whether it is the exterior or interior of building G based on the difference between the first sunshine information based on the weather forecast and the second sunshine information based on the sunshine sensor 4. Specifically, as... Figure 3 As shown, the sunshine information contained in the weather forecast or the sunshine information estimated based on the weather forecast is obtained as the first sunshine information (S11), and the second sunshine information based on the sunshine sensor 4 is obtained (S12). Then, it is determined whether the difference between the first sunshine information and the second sunshine information is greater than a predetermined value (S13). If the determination result is YES (for example, ...), Figure 4 If the shaded area is determined to be inside the building G (S14), and if the determination result is NO, it is determined to be outside the building G (S15).

[0050] The reference temperature setting unit 22 sets a reference temperature based on the environment estimated by the environment estimation unit 21 from multiple temperature information sources. These multiple temperature information sources include first temperature information based on weather forecasts (refer to...). Figure 5 The reference temperature setting unit 22 sets the reference temperature to the first temperature information when the electric vehicle V is parked in the environment outside the building G, and sets the reference temperature to the second temperature information when the electric vehicle V is parked in the environment inside the building G.

[0051] The external air temperature sensor 3 mounted on the electric vehicle V tends to heat up when exposed to sunlight. Therefore, when the electric vehicle V is parked outside a building G, the reference temperature setting unit 22 in this embodiment can accurately predict the temperature change of the battery B by setting the reference temperature used to predict the temperature change of the battery B to first temperature information based on weather forecasts. On the other hand, when the electric vehicle V is parked inside a building G, the temperature inside the building G deviates from the first temperature information. Therefore, by setting the second temperature information based on the external air temperature sensor 3 mounted on the electric vehicle V as the reference temperature, the temperature change of the battery B can be predicted with high accuracy.

[0052] The calibration value setting unit 23 sets a calibration value based on the parking environment of the electric vehicle V. For example, if the electric vehicle V is parked outside a building G, the temperature of the battery B will vary depending on whether it is in the sun or in the shade; in other words, it will vary depending on the sunlight conditions. Therefore, as... Figure 6 As shown, a correction value is set based on the second sunlight information based on sunlight sensor 4.

[0053] The battery temperature change prediction unit 24 predicts the temperature change of battery B based on the reference temperature set by the reference temperature setting unit 22 and the correction value set by the correction value setting unit 23. For example, when the electric vehicle V is parked in the exterior of building G, the temperature change of battery B is predicted based on first temperature information as a reference temperature and a correction value set according to sunlight conditions. When the electric vehicle V is parked in the interior of building G, the temperature change of battery B is predicted based on second temperature information as a reference temperature.

[0054] The battery temperature regulation unit 25 regulates the temperature of battery B based on the temperature change of battery B predicted by the battery temperature change prediction unit 24. For example, if the battery temperature regulation unit 25 predicts that the temperature of battery B is higher than the target temperature range, it controls the temperature regulation device 9 to cool battery B; if the battery temperature regulation unit 25 predicts that the temperature of battery B is lower than the target temperature range, it controls the temperature regulation device 9 to heat battery B. This prevents situations where the output of battery B is limited or insufficient due to excessively high or low battery temperature when the electric vehicle V is started after parking, thus improving the convenience of the electric vehicle V.

[0055] Next, refer to Figure 7 The battery temperature control process of the control unit 2 that implements the above-mentioned functional configuration will be explained.

[0056] like Figure 7 As shown, during the battery temperature control process, the control unit 2 first determines whether the electric vehicle V is in a parked state based on the output of the vehicle speed sensor 7 (S21). If the determination result is NO, the process is repeated until it is determined that the electric vehicle V is in a parked state. If the determination result is YES, the process proceeds to step S22.

[0057] When entering step S22, the control unit 2 estimates the parking environment of the electric vehicle V and determines whether the environment is outdoors. If the determination result is YES, the control unit 2 proceeds to step S23; if the determination result is NO, it proceeds to step S27.

[0058] When proceeding to step S23, the control unit 2 acquires first temperature information based on the weather forecast as a reference temperature, and then determines whether the solar radiation amount (second solar radiation information) based on the solar radiation sensor 4 exceeds a predetermined value (S24). If the determination result is YES, a correction value is set based on the solar radiation amount (second solar radiation information) (S25), and then the temperature regulating device 9 is controlled based on the first temperature information and the correction value (S26). Furthermore, if the determination result in step S24 is NO, the control unit 2 skips step S25 and controls the temperature regulating device 9 based on the first temperature information (S26).

[0059] On the other hand, when step S27 is entered, the control unit 2 acquires the second temperature information based on the external air temperature sensor 3 as the reference temperature, and then controls the temperature regulating device 9 based on the second temperature information (S28).

[0060] Next, refer to Figure 8 Another example illustrating the battery temperature control process is provided. However, for... Figure 7 The battery temperature control process shown is a common control process, using the same control flow as... Figure 7 The same reference numerals are used in the accompanying drawings illustrating the battery temperature control process, thus omitting the reference numerals for... Figure 7 Explanation of the battery temperature control process shown.

[0061] like Figure 8 As shown, in another example of battery temperature control, if the determination result in step S22 is NO, the control unit 2 determines whether the parking location of the electric vehicle V is a pre-recorded location (e.g., in its own garage) (S31). If the determination result is NO, similar to... Figure 7 The battery temperature control process shown involves the control unit 2 acquiring second temperature information based on the external air temperature sensor 3 as a reference temperature (S27), and then controlling the temperature regulating device 9 based on the second temperature information (S28). On the other hand, if the judgment result in step S31 is YES, the control unit 2 acquires first temperature information based on the weather forecast (S32), sets a correction value based on the information of the recorded location (S33), and then controls the temperature regulating device 9 based on the first temperature information and the correction value (S28).

[0062] According to another example of this battery temperature control process, by setting a correction value based on the location status of places where the electric vehicle V frequently parks, corrections that take into account the thermal insulation capacity of the recorded location can be made. Even inside a building G, the temperature change of the battery B can be predicted with high accuracy using first temperature information based on weather forecasts. It should be noted that the thermal insulation capacity (time constant) of the recorded location is pre-calculated based on second temperature information based on external air temperature sensor 3 and first temperature information based on weather forecasts, and can be stored in memory or the like in association with the recorded location.

[0063] Various embodiments have been described above with reference to the accompanying drawings, but the present invention is not limited to these examples. It is obvious that those skilled in the art will conceive of various modifications or alterations within the scope of the claimed protection, and it is understood that these modifications or alterations also fall within the technical scope of the present invention. Furthermore, the constituent elements in the above embodiments can be arbitrarily combined without departing from the spirit of the invention.

[0064] The following items are described in at least one part of this specification. It should be noted that although the components and other elements corresponding to the above embodiments are shown in parentheses, the invention is not limited thereto.

[0065] (1) A battery temperature control system (battery temperature control system 1) that maintains the temperature of a battery (battery B) mounted on an electric vehicle (electric vehicle V) within a target temperature range during the parking period of the electric vehicle, wherein,

[0066] The battery temperature control system includes:

[0067] An environmental estimation unit (environmental estimation unit 21) estimates the environment in which the electric vehicle is parked;

[0068] The reference temperature setting unit (reference temperature setting unit 22) sets a reference temperature from multiple temperature information based on the environment estimated by the environment estimation unit.

[0069] A battery temperature change prediction unit (battery temperature change prediction unit 24) predicts the temperature change of the battery based on the reference temperature; and

[0070] The battery temperature regulation unit (battery temperature regulation unit 25) regulates the temperature of the battery based on the temperature change of the battery.

[0071] According to (1), a reference temperature is set from multiple temperature information, and the temperature change of the battery is predicted based on the reference temperature. Therefore, the temperature change of the battery can be predicted with high accuracy regardless of the parking environment of the electric vehicle.

[0072] (2) According to the battery temperature control system described in (1), wherein,

[0073] The multiple temperature information includes first temperature information based on weather forecasts and second temperature information based on external air temperature sensors (external air temperature sensor 3) mounted on the electric vehicle.

[0074] When the environment in which the electric vehicle is parked is outside a building, the reference temperature is the first temperature information.

[0075] When the environment in which the electric vehicle is parked is inside a building, the reference temperature is the second temperature information.

[0076] The external air temperature sensor mounted on the electric vehicle experiences a temperature rise due to heat when exposed to sunlight. Therefore, according to (2), when the electric vehicle is parked outside a building, the battery temperature change can be predicted with high accuracy by using first temperature information based on weather forecasts. On the other hand, when the electric vehicle is parked inside a building, the temperature inside the building deviates from the first temperature information based on weather forecasts. Therefore, the battery temperature change can be predicted with high accuracy by using second temperature information based on the external air temperature sensor mounted on the electric vehicle.

[0077] (3) The battery temperature control system according to (2), wherein,

[0078] The environmental estimation unit determines whether the environment is outside or inside the building based on the image acquisition device (camera 5) mounted on the electric vehicle.

[0079] According to (3), by using an image acquisition device mounted on an electric vehicle, it is easy to determine whether it is the exterior or interior of a building.

[0080] (4) The battery temperature control system according to (2), wherein,

[0081] The environmental estimation unit determines whether it is the exterior or interior of the building based on the difference between first sunshine information based on weather forecast and second sunshine information based on sunshine sensor (sunshine sensor 4) mounted on the electric vehicle.

[0082] According to (4), based on the difference between the first sunshine information based on the weather forecast and the second sunshine information based on the sunshine sensor mounted on the electric vehicle, it is easy to infer whether the electric vehicle is parked outside or inside the building.

[0083] (5) The battery temperature control system according to any one of (1) to (4), wherein,

[0084] The battery temperature control system also features:

[0085] The correction value setting unit (correction value setting unit 23) sets a correction value based on the environment in which the electric vehicle is parked.

[0086] The battery temperature change prediction unit predicts the temperature change of the battery based on the reference temperature and the correction value.

[0087] According to (5), the temperature change of the battery can be predicted with high accuracy by predicting the temperature change of the battery based on the reference temperature and the correction value.

[0088] (6) The battery temperature control system according to (5), wherein,

[0089] When the environment in which the electric vehicle is parked is outside a building, the correction value setting unit sets the correction value based on second sunlight information from a sunlight sensor (sunlight sensor 4) mounted on the electric vehicle.

[0090] According to (6), when the electric vehicle is parked outside a building, the temperature change of the battery can be predicted with greater accuracy by setting a correction value based on the amount of sunlight.

[0091] (7) The battery temperature control system according to (1), wherein,

[0092] The multiple temperature information includes first temperature information based on weather forecasts and second temperature information based on external air temperature sensors mounted on the electric vehicle.

[0093] When the environment in which the electric vehicle is parked is outside a building, the reference temperature is the first temperature information.

[0094] When the environment in which the electric vehicle is parked is inside a building and the location of the electric vehicle is a pre-recorded location, the reference temperature is the first temperature information.

[0095] When the environment in which the electric vehicle is parked is inside a building and the location of the electric vehicle is not a pre-recorded location, the reference temperature is the second temperature information.

[0096] According to (7), when the location of the electric vehicle is a pre-recorded location, even if the environment in which the electric vehicle is parked is inside a building, the temperature change of the battery can be predicted with high accuracy based on the first temperature information based on the weather forecast.

[0097] (8) The battery temperature control system according to (7), wherein,

[0098] The battery temperature control system also features:

[0099] The correction value setting unit (correction value setting unit 23) sets a correction value based on the environment in which the electric vehicle is parked.

[0100] When the environment in which the electric vehicle is parked is inside a building and the location of the electric vehicle is a pre-recorded location,

[0101] The correction value setting unit sets the correction value based on the heat insulation capacity of the entered location.

[0102] According to (8), by setting a correction value based on the location status of places where electric vehicles are frequently parked, the temperature change of the battery can be predicted with higher accuracy based on the thermal insulation performance of the location.

Claims

1. A battery temperature control system that maintains the temperature of a battery mounted on an electric vehicle within a target temperature range during the vehicle's parking period, wherein, The battery temperature control system includes: An environment estimation unit that estimates the environment in which the electric vehicle is parked when the electric vehicle is parked. The reference temperature setting unit sets a reference temperature from multiple temperature information based on the environment estimated by the environment estimation unit. A battery temperature change prediction unit predicts the temperature change of the battery based on the reference temperature. as well as A battery temperature regulation unit adjusts the battery temperature based on temperature changes within the battery. The multiple temperature information includes first temperature information based on weather forecasts and second temperature information based on external air temperature sensors mounted on the electric vehicle. When the environment in which the electric vehicle is parked is outside a building, the reference temperature is the first temperature information. When the environment in which the electric vehicle is parked is inside a building, the reference temperature is the second temperature information.

2. The battery temperature control system according to claim 1, wherein, The environmental estimation unit determines whether the environment is outside or inside the building based on the image acquisition device mounted on the electric vehicle.

3. The battery temperature control system according to claim 1, wherein, The environmental estimation unit determines whether the object is outside or inside the building based on the difference between first sunshine information based on weather forecasts and second sunshine information based on a sunshine sensor mounted on the electric vehicle.

4. The battery temperature control system according to any one of claims 1 to 3, wherein, The battery temperature control system also features: The correction value setting unit sets a correction value based on the environment in which the electric vehicle is parked. The battery temperature change prediction unit predicts the temperature change of the battery based on the reference temperature and the correction value.

5. The battery temperature control system according to claim 4, wherein, When the environment in which the electric vehicle is parked is outside a building, the correction value setting unit sets the correction value based on second sunlight information from a sunlight sensor mounted on the electric vehicle.

6. The battery temperature control system according to claim 1, wherein, The multiple temperature information includes first temperature information based on weather forecasts and second temperature information based on external air temperature sensors mounted on the electric vehicle. When the environment in which the electric vehicle is parked is outside a building, the reference temperature is the first temperature information. When the environment in which the electric vehicle is parked is inside a building and the location of the electric vehicle is a pre-recorded location, the reference temperature is the first temperature information. When the environment in which the electric vehicle is parked is inside a building and the location of the electric vehicle is not a pre-recorded location, the reference temperature is the second temperature information.

7. The battery temperature control system according to claim 6, wherein, The battery temperature control system also features: The correction value setting unit sets a correction value based on the environment in which the electric vehicle is parked. When the environment in which the electric vehicle is parked is inside a building and the location of the electric vehicle is a pre-recorded location, The correction value setting unit sets the correction value based on the heat insulation capacity of the entered location.

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