A method, system and vehicle for determining the battery cell temperature of a double-layer liquid-cooled battery

Abstract

The present application provides a method, system and vehicle for determining the cell temperature of a double-layer liquid-cooled battery, which is applied to the field of battery technology, wherein the double-layer liquid-cooled battery includes: a first liquid-cooled plate, a battery module and a second liquid-cooled plate arranged in a vertical direction, and the method includes: obtaining the operating condition information of the vehicle and the ambient temperature of the battery; according to the operating condition information and the ambient temperature, determining that the temperature value detected by the first temperature sensor or the second temperature sensor is the cell temperature, wherein the first temperature sensor is arranged on the Busbar corresponding to an edge cell in the battery module, and the second temperature sensor is arranged on the top cover of the middle cell in the battery module. The present application provides two types of temperature sensors in a double-layer liquid-cooled battery, and selects one for use based on the actual operating condition information and ambient temperature. It solves the problem that the traditional NTC arrangement cannot be applied to double-layer liquid-cooled batteries that can be charged at a high rate, and can ensure the accuracy of the cell temperature under all operating conditions.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a method, system and vehicle for determining the temperature of a battery cell of a double-layer liquid-cooled battery. Background Art

[0002] In the power battery system, the function of the temperature sensor (Negative Temperature Coefficient, NTC) of the Battery Management System (BMS) is to ensure that the highest and lowest temperatures of the system battery cells can be detected. For common systems that are generally single-sided heating or cooling, the NTC is generally only placed on the battery cell top cover or the battery tab busbar away from the heating and cooling positions, thereby ensuring that the lowest system temperature is measured under heating conditions and the highest system temperature is measured under cooling conditions.

[0003] However, for NTC placed only on the top cover of the battery cell, the collected temperature will be higher than the battery cell temperature under certain working conditions. When using the car in winter, after driving, the battery cell stops heating itself, but due to the anisotropic thermal conductivity of the battery cell itself, the battery cell mainly dissipates heat to the bottom, and the temperature at the bottom of the battery cell will be lower than the NTC temperature on the top cover of the battery cell. At this time, if charging is started, the battery cell temperature will be lower than the temperature collected by NTC for a period of time after the thermal management system responds, resulting in the risk of charging rate mismatch in a short period of time.

[0004] For example: a user drives at -20℃ and performs fast charging after a period of time after driving. At this time, due to the thermal conductivity of the battery cell, the lowest temperature of the battery cell after dissipating heat to the bottom may be -15℃, while the NTC of the battery cell cover is -9℃. Therefore, fast charging at a current of -9℃ may cause risks such as lithium plating (which may cause short circuit and fire in the long run). The bottom temperature will be higher than the NTC temperature of the battery cell cover only after the thermal management system is started for a period of time. The battery tab busbar dissipates heat faster than the bottom of the battery cell, so this problem will not occur if it is arranged on the battery tab busbar.

[0005] For NTCs that are only welded on the busbar of the battery tab, the temperature will rise due to the influence of current. Under certain working conditions, the temperature collected at this location needs to be corrected to ensure that the corrected temperature is consistent with the actual temperature of the battery cell. This requires a lot of calibration experiment resources, and the corrected temperature is not the actual collected temperature. User scenarios that are not covered in the calibration test may occur, resulting in inaccurate temperature and risks.

[0006] The above are the layout and problems of traditional NTC. As for the new double-layer liquid-cooled blade battery system with high-rate fast charging, on the one hand, the double-layer liquid-cooled blade battery structure makes it impractical to stay away from the single-sided heating and cooling surface. On the other hand, high-rate charging requires ensuring the accuracy of the NTC temperature. The solution of welding it separately to the battery tab busbar or placing it on the top cover of the battery cell is not feasible. Therefore, a safe and reliable NTC layout is an issue that needs to be solved urgently. Summary of the invention

[0007] The technical purpose to be achieved by the embodiments of the present application is to provide a method, system and vehicle for determining the battery cell temperature of a double-layer liquid-cooled battery, so as to solve the problem that the existing NTC setting method cannot accurately know the exact temperature of the double-layer liquid-cooled battery.

[0008] In order to solve the above technical problems, an embodiment of the present application provides a method for determining the temperature of a battery cell of a double-layer liquid-cooled battery, wherein the double-layer liquid-cooled battery comprises: a first liquid-cooling plate, a battery module, and a second liquid-cooling plate arranged in a vertical direction, and the method comprises:

[0009] Acquire operating condition information of the vehicle and the ambient temperature of the battery, wherein the operating condition information includes at least one of a driving condition, a parking condition, a fast charging condition, and a slow charging condition;

[0010] According to the operating condition information and the ambient temperature, the temperature value detected by the first temperature sensor or the second temperature sensor is determined to be the battery cell temperature, wherein the first temperature sensor is arranged on a battery tab busbar corresponding to an edge battery cell in the battery module, and the second temperature sensor is arranged on a top cover of an intermediate battery cell in the battery module, in the vertical direction, the battery tab busbar is arranged in the middle part of the top cover of the corresponding battery cell, and the second temperature sensor is arranged between the battery tab busbar and the first liquid cooling plate.

[0011] Specifically, in the method as described above, determining the temperature value detected by the first temperature sensor or the second temperature sensor as the battery cell temperature according to the operating condition information and the ambient temperature includes:

[0012] When the operating condition information is a slow charging condition and the ambient temperature is greater than or equal to a preset temperature threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor;

[0013] When the operating condition information is the driving operating condition or the parking operating condition, and the ambient temperature is greater than or equal to the temperature threshold, determining that the battery cell temperature is a temperature value detected by the second temperature sensor;

[0014] When the operating condition information is the parking condition and the ambient temperature is less than the temperature threshold, it is determined that the battery cell temperature is a temperature value detected by the first temperature sensor.

[0015] Furthermore, in the above method, determining the temperature value detected by the first temperature sensor or the second temperature sensor as the battery cell temperature according to the operating condition information and the ambient temperature, further includes:

[0016] Acquiring corresponding reference information according to the operating condition information and the ambient temperature;

[0017] Determine, according to the operating condition information, the ambient temperature, and the reference information, that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature.

[0018] Furthermore, the method as described above, obtaining corresponding reference information according to the operating condition information and the ambient temperature, includes:

[0019] When the operating condition information is the fast charging operating condition and the ambient temperature is less than the temperature threshold, the reference information obtained is the thermal management time and the charging current of the thermal management system;

[0020] When the operating condition information is the fast charging operating condition and the ambient temperature is greater than or equal to the temperature threshold, the reference information obtained includes at least the charging current;

[0021] When the operating condition information is the slow charging operating condition and the ambient temperature is less than the temperature threshold, the reference information obtained is the thermal management time;

[0022] When the operating condition information is the driving operating condition and the ambient temperature is less than the temperature threshold, the reference information obtained is the average vehicle speed within a preset time and / or the thermal management time.

[0023] Specifically, the method as described above, when the operating condition information is the fast charging operating condition, determining the temperature value detected by the first temperature sensor or the second temperature sensor as the battery cell temperature according to the operating condition information, the ambient temperature and the reference information, includes:

[0024] When the ambient temperature is less than a preset temperature threshold and the thermal management time is less than a preset time threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor;

[0025] When the ambient temperature is lower than the temperature threshold, the thermal management time is greater than or equal to the time threshold, and the charging current is less than or equal to a preset current threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor;

[0026] When the ambient temperature is lower than the temperature threshold, the thermal management time is greater than or equal to the time threshold, and the charging current is greater than the current threshold, determining that the battery cell temperature is a temperature value detected by the second temperature sensor;

[0027] When the ambient temperature is greater than or equal to the temperature threshold and the charging current is greater than the current threshold, determining that the battery cell temperature is a temperature value detected by the second temperature sensor;

[0028] When the ambient temperature is greater than or equal to the temperature threshold and the charging current is less than or equal to the current threshold, it is determined that the battery cell temperature is a temperature value detected by the first temperature sensor.

[0029] Specifically, the method as described above, when the operating condition information is the slow charging operating condition, determining the temperature value detected by the first temperature sensor or the second temperature sensor as the battery cell temperature according to the operating condition information, the ambient temperature and the reference information, includes:

[0030] When the ambient temperature is lower than a preset temperature threshold and the thermal management time is greater than or equal to a preset time threshold, determining that the battery cell temperature is a temperature value detected by the second temperature sensor;

[0031] When the ambient temperature is less than the temperature threshold and the thermal management time is less than the time threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor;

[0032] When the ambient temperature is greater than or equal to the temperature threshold, it is determined that the battery cell temperature is a temperature value detected by the first temperature sensor.

[0033] Specifically, the method as described above, when the operating condition information is the driving operating condition, determining the temperature value detected by the first temperature sensor or the second temperature sensor as the battery cell temperature according to the operating condition information, the ambient temperature and the reference information, includes:

[0034] When the ambient temperature is less than a preset temperature threshold and the average vehicle speed is less than or equal to a preset vehicle speed threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor;

[0035] When the ambient temperature is lower than a preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management system is not started, determining that the battery cell temperature is a temperature value detected by the second temperature sensor;

[0036] When the ambient temperature is lower than a preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management time is lower than or equal to a preset time threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor;

[0037] When the ambient temperature is lower than a preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management time is higher than the time threshold, determining that the battery cell temperature is a temperature value detected by the second temperature sensor;

[0038] When the ambient temperature is greater than or equal to the temperature threshold, it is determined that the battery cell temperature is a temperature value detected by the second temperature sensor.

[0039] Another embodiment of the present application further provides a battery management system for a double-layer liquid-cooled battery, the double-layer liquid-cooled battery comprising: a first liquid-cooling plate, a battery module, and a second liquid-cooling plate arranged in a vertical direction, the battery management system comprising:

[0040] A first processing module is used to obtain the operating condition information of the vehicle and the ambient temperature of the battery, wherein the operating condition information includes at least one of a driving condition, a parking condition, a fast charging condition, and a slow charging condition;

[0041] The second processing module is used to determine that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature based on the operating condition information and the ambient temperature, wherein the first temperature sensor is arranged on a battery tab busbar corresponding to an edge battery cell in the battery module, and the second temperature sensor is arranged on a top cover of an intermediate battery cell in the battery module, in the vertical direction, the battery tab busbar is arranged in the middle part of the top cover of the corresponding battery cell, and the second temperature sensor is arranged between the battery tab busbar and the first liquid cooling plate.

[0042] Another embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the computer program implements the steps of a method for determining the temperature of a battery cell of a double-layer liquid-cooled battery as described above.

[0043] Yet another embodiment of the present application provides a vehicle, comprising: the battery management system as described above.

[0044] Compared with the prior art, the method, system and vehicle for determining the cell temperature of a double-layer liquid-cooled battery provided in the embodiments of the present application have at least the following beneficial effects:

[0045] In this embodiment, two types of temperature sensors are provided in the double-layer liquid-cooled battery, and when the battery cell temperature is required, the vehicle operating condition information and the ambient temperature outside the battery are first obtained, and the temperature value detected by one type of temperature sensor is determined as the battery cell temperature based on the specific operating condition information and ambient temperature. This solves the problem that the traditional NTC arrangement cannot be applied to double-layer liquid-cooled batteries that can be charged at a high rate, and can ensure the accuracy of the battery cell temperature under all operating conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is one of the flow charts of a method for determining the cell temperature of a double-layer liquid-cooled battery of the present application;

[0047] Figure 2 This is a schematic diagram of the structure of the double-layer liquid-cooled battery in this application;

[0048] Figure 3 for Figure 2 Partial schematic diagram at A in the middle;

[0049] Figure 4 This is one of the flow charts of a method for determining the cell temperature of a double-layer liquid-cooled battery of the present application;

[0050] Figure 5 This is a schematic diagram of the structure of the battery management system in this application. DETAILED DESCRIPTION

[0051] In order to make the technical problems, technical solutions and advantages to be solved by the application clearer, the following will be described in detail in conjunction with the accompanying drawings and specific embodiments. In the following description, specific details such as specific configurations and components are provided only to help fully understand the embodiments of the application. Therefore, it should be clear to those skilled in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the application. In addition, for clarity and brevity, the description of known functions and structures has been omitted.

[0052] It should be understood that the references to "one embodiment" or "an embodiment" throughout the specification mean that the specific features, structures, or characteristics associated with the embodiment are included in at least one embodiment of the present application. Therefore, the references to "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0053] In the various embodiments of the present application, it should be understood that the size of the serial numbers of the following processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0054] It should be understood that the term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0055] In the embodiments provided in the present application, it should be understood that "B corresponding to A" means that B is associated with A, and B can be determined according to A. However, it should also be understood that determining B according to A does not mean determining B only according to A, and B can also be determined according to A and / or other information.

[0056] See also Figure 1 and Figure 2 A preferred embodiment of the present application provides a method for determining the temperature of a battery cell of a double-layer liquid-cooled battery, wherein the double-layer liquid-cooled battery comprises: a first liquid-cooling plate, a battery module, and a second liquid-cooling plate arranged in a vertical direction, and the method comprises:

[0057] Step S101, obtaining the vehicle operating condition information and the ambient temperature of the battery, wherein the operating condition information includes at least one of a driving condition, a parking condition, a fast charging condition, and a slow charging condition;

[0058] Step S102, based on the operating condition information and the ambient temperature, determine that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature, wherein the first temperature sensor is arranged on a battery tab busbar corresponding to an edge battery cell in the battery module, and the second temperature sensor is arranged on the top cover of the middle battery cell in the battery module, in the vertical direction, the battery tab busbar is arranged in the middle part of the top cover of the corresponding battery cell, and the second temperature sensor is arranged between the battery tab busbar and the first liquid cooling plate.

[0059] In a specific embodiment of the present application, the method for determining the temperature of a battery cell of a double-layer liquid-cooled battery is provided and applied to a double-layer liquid-cooled battery. Figure 2 and Figure 3As shown, the double-layer liquid-cooled battery includes: a first liquid-cooling plate 1, a battery module 3, and a second liquid-cooling plate 2 arranged in a vertical direction. The battery cells in the battery module 3 are arranged in a horizontal direction. The upper and lower ends of the battery module 3 can be thermally managed by two liquid-cooling plates. In order to ensure the accuracy of the final battery cell temperature, in this embodiment, two types of temperature sensors are provided in the double-layer liquid-cooled battery. When it is necessary to obtain the battery cell temperature, the operating condition information of the vehicle and the ambient temperature outside the battery are first obtained, and the temperature value detected by one type of temperature sensor is determined as the battery cell temperature based on the specific operating condition information and the ambient temperature. This solves the problem that the traditional NTC layout strategy cannot be applied to double-layer liquid-cooled batteries that can be charged at a high rate, and can ensure the accuracy of the battery cell temperature under all operating conditions.

[0060] Specifically, the first temperature sensor 5 is arranged on the battery tab busbar 4 corresponding to an edge battery cell in the battery module. Regardless of the battery module 3 or the battery system, the lowest temperature before active thermal management intervention will appear at the edge. Therefore, compared with the traditional NTC arranged only at the top cover of the battery cell, the first temperature sensor 5 arranged on the battery tab busbar 4 has the characteristics of large thermal conductivity and fast heat dissipation of the battery tab busbar 4. When the vehicle charging and discharging current is small or charging and discharging is stopped, the temperature drop of the battery tab busbar 4 is faster than the part of the battery cell close to the second liquid cooling plate 2, so it can ensure that the system measures the lowest temperature of the system, solving the risk of mismatching the charging rate under charging conditions. In low-temperature pure heating conditions, since the NTC is not on the battery cell body, it will not be affected by the inaccurate temperature caused by uneven heating on both sides.

[0061] The second temperature sensor 6 is arranged on the top cover of the middle battery cell in the battery module. For the battery module 3 or the system itself, this area is the highest temperature of the system before the active thermal management system intervenes. Compared with the traditional NTC that is only welded to the battery tab busbar 4, the NTC on the top cover of the battery cell is not affected by the abnormal change of thermal conductivity temperature due to current changes. For example, frequent acceleration and deceleration will cause the temperature of the battery tab busbar 4 to rise and fall rapidly, thereby causing the maximum power allowed to be output by the battery system to change, affecting the actual user experience. On the other hand, due to the influence of factors such as the internal resistance or welding of the battery tab busbar 4, when charging with a large current, the temperature of the battery tab busbar 4 will also be significantly higher than the temperature of the battery body, thereby causing a false high temperature and resulting in a reduction in the charging current, which also affects the user experience.

[0062] It should be noted that the battery cell temperature described herein is the highest temperature value and the lowest temperature value detected by the first temperature sensor 5 or the second temperature sensor 6 .

[0063] It should also be noted that Figure 3 The reference numeral 7 in the figure indicates the tab structure of the battery cell.

[0064] In a specific embodiment of the present application, based on the method described above, an example is given of how to determine, according to the operating condition information and the ambient temperature, that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature, specifically including:

[0065] When the operating condition information is a slow charging condition, and the ambient temperature is greater than or equal to a preset temperature threshold, it can be determined that the battery is in a non-low temperature environment. At this time, the heating has little effect on each temperature sensor, and the current during charging is small. At this time, the position of the edge battery cell corresponds to the lowest temperature of the battery. Therefore, the battery cell temperature is determined to be the temperature value detected by the first temperature sensor, which can ensure the accuracy of the battery cell temperature during slow charging;

[0066] When the operating condition information is the driving operating condition or the parking operating condition, and the ambient temperature is greater than or equal to the temperature threshold, it can be determined that the battery is in a non-low temperature environment. At this time, heating has little effect on each temperature sensor. In order to avoid the influence of the power demand of the vehicle under the driving or parking conditions on the temperature value detected by the temperature sensor, the battery cell temperature is determined to be the temperature value detected by the second temperature sensor;

[0067] When the operating condition information is the parking condition and the ambient temperature is lower than the temperature threshold, it can be determined that the battery is in a low temperature environment. At this time, the battery needs to be heated. To avoid the influence of heating on the temperature value, the battery cell temperature is determined to be the temperature value detected by the first temperature sensor.

[0068] See also Figure 4 Further, the method as described above, determining the temperature value detected by the first temperature sensor or the second temperature sensor as the battery cell temperature according to the operating condition information and the ambient temperature, further includes:

[0069] Step S401, acquiring corresponding reference information according to the working condition information and the ambient temperature;

[0070] Step S402 , determining, according to the operating condition information, the ambient temperature and the reference information, that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature.

[0071] In another embodiment of the present application, when determining the temperature sensor corresponding to the battery cell temperature, in order to ensure accuracy, corresponding reference information is also obtained based on the complex characteristics under specific working conditions. The reference information includes but is not limited to: the thermal management time of the thermal management system, the charging current, the average vehicle speed within a preset time, etc. Further judgment based on the reference information can improve the accuracy of the battery cell temperature.

[0072] It should be noted that the reference information described below is mainly parameters used for judgment, and other parameters may also be obtained but are not used for judgment.

[0073] In a specific embodiment, the method described above, specifically based on the working condition information and the ambient temperature, obtains corresponding reference information, including at least one of the following:

[0074] When the operating condition information is the fast charging operating condition and the ambient temperature is less than the temperature threshold, it is determined that the battery is in a low temperature environment, and the battery needs to be heated and charged at this time, so the reference information obtained is the thermal management time and charging current of the thermal management system;

[0075] When the operating condition information is the fast charging operating condition and the ambient temperature is greater than or equal to the temperature threshold, it can be determined that the battery is in a non-low temperature environment, and heating has little effect on each temperature sensor at this time, so the reference information obtained includes at least the charging current;

[0076] When the operating condition information is the slow charging operating condition and the ambient temperature is less than the temperature threshold, it is determined that the battery is in a low temperature environment. At this time, the battery needs to be heated and charged, but since the charging current is small, the current has little effect on the sensor, so the reference information obtained is the thermal management time;

[0077] When the operating condition information is the driving condition and the ambient temperature is less than the temperature threshold, it is determined that the battery is in a low temperature environment. At this time, the battery may need to be heated, and under the driving condition, the vehicle needs to discharge and the discharge current is related to the vehicle speed. Therefore, the reference information obtained is the average vehicle speed within a preset time and / or the thermal management time.

[0078] The following provides examples of how to determine the temperature value detected by the first temperature sensor or the second temperature sensor as the cell temperature according to the operating condition information, the ambient temperature and the reference information under fast charging conditions, slow charging conditions and driving conditions.

[0079] In one embodiment, specifically, the method as described above, when the operating condition information is the fast charging operating condition, determining the temperature value detected by the first temperature sensor or the second temperature sensor as the battery cell temperature according to the operating condition information, the ambient temperature and the reference information, includes:

[0080] When the ambient temperature is lower than a preset temperature threshold and the thermal management time is lower than a preset time threshold, it is determined that the battery is in a low temperature environment. At this time, the battery needs to be heated and the heating time is short. At this time, the liquid cooling plate has a greater impact on the temperature of the second temperature sensor. Therefore, it is determined that the battery cell temperature is the temperature value detected by the first temperature sensor.

[0081] When the ambient temperature is lower than the temperature threshold, the thermal management time is greater than or equal to the time threshold, and the charging current is less than or equal to the preset current threshold, it is determined that the battery is in a low temperature environment. At this time, the battery needs to be heated and the heating time is longer than the time threshold, so that the liquid cooling plate has less influence on the temperature of the second temperature sensor. At the same time, since the charging current is smaller than the current threshold, its influence on the first temperature sensor is also smaller, and the heat dissipation performance of the position where the first temperature sensor is located is better, so the battery cell temperature is determined to be the temperature value detected by the first temperature sensor;

[0082] When the ambient temperature is lower than the temperature threshold, the thermal management time is greater than or equal to the time threshold, and the charging current is greater than the current threshold, it is determined that the battery is in a low temperature environment. At this time, the battery needs to be heated and the heating time is longer than the time threshold, so that the liquid cooling plate has less influence on the temperature of the second temperature sensor. At the same time, since the charging current is larger than the current threshold, it has a greater influence on the first temperature sensor. Therefore, the battery cell temperature is determined to be the temperature value detected by the second temperature sensor.

[0083] When the ambient temperature is greater than or equal to the temperature threshold and the charging current is greater than the current threshold, it is determined that the battery is in a non-low-temperature environment. At this time, the battery does not need to be heated or heating has little effect on the temperature of the battery cell. However, since the charging current is larger than the current threshold, it has a greater impact on the first temperature sensor. Therefore, it is determined that the battery cell temperature is the temperature value detected by the second temperature sensor.

[0084] When the ambient temperature is greater than or equal to the temperature threshold and the charging current is less than or equal to the current threshold, it is determined that the battery is in a non-low-temperature environment. At this time, the battery does not need to be heated or heating has little effect on the temperature of the battery cell. Since the charging current is smaller than the current threshold, its effect on the first temperature sensor is smaller, and the heat dissipation performance of the location of the first temperature sensor is better. Therefore, the battery cell temperature is determined to be the temperature value detected by the first temperature sensor.

[0085] In another embodiment, specifically, the method as described above, when the operating condition information is the slow charging condition, determining the temperature value detected by the first temperature sensor or the second temperature sensor as the battery cell temperature according to the operating condition information, the ambient temperature and the reference information, includes:

[0086] When the ambient temperature is lower than a preset temperature threshold and the thermal management time is greater than or equal to a preset time threshold, it is determined that the battery is in a low temperature environment. At this time, the battery needs to be heated and the heating time is longer than the time threshold, so that at this time, the liquid cooling plate has less influence on the temperature of the second temperature sensor. Therefore, it is determined that the battery cell temperature is the temperature value detected by the second temperature sensor.

[0087] When the ambient temperature is lower than the temperature threshold and the thermal management time is lower than the time threshold, it is determined that the battery is in a low temperature environment. At this time, the battery needs to be heated and the heating time is longer than the time threshold, so that the liquid cooling plate has a greater impact on the temperature of the second temperature sensor. Therefore, it is determined that the battery cell temperature is the temperature value detected by the first temperature sensor.

[0088] When the ambient temperature is greater than or equal to the temperature threshold, it is determined that the battery is in a non-low-temperature environment. At this time, the battery does not need to be heated or heating has little effect on the temperature of the battery cell, and the heat dissipation performance of the location of the first temperature sensor is better. Therefore, the battery cell temperature is determined to be the temperature value detected by the first temperature sensor.

[0089] In another embodiment, specifically, the method as described above, when the operating condition information is the driving operating condition, determining the temperature value detected by the first temperature sensor or the second temperature sensor as the battery cell temperature according to the operating condition information, the ambient temperature and the reference information, includes:

[0090] When the ambient temperature is less than a preset temperature threshold and the average vehicle speed is less than or equal to a preset vehicle speed threshold, it is determined that the battery is in a low temperature environment. At this time, the battery needs to be heated, so that the liquid cooling plate has an impact on the temperature of the second temperature sensor. Since the average vehicle speed at this time is smaller than the vehicle speed threshold, the impact of battery discharge on the first temperature sensor is small. Therefore, the battery cell temperature is determined to be the temperature value detected by the first temperature sensor.

[0091] When the ambient temperature is lower than the preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management system is not started, it is determined that the battery is in a low temperature environment, and the battery needs to be heated at this time. However, since the thermal management system is not started at this time, that is, the thermal management time is zero, the liquid cooling plate has no effect on the temperature of the second temperature sensor at this time. Moreover, since the average vehicle speed at this time is larger than the vehicle speed threshold, it indicates that the vehicle is in high-speed or intense driving, which makes the battery tab busbar generate a large amount of heat, that is, the battery discharge has an effect on the first temperature sensor, and therefore the battery cell temperature is determined to be the temperature value detected by the second temperature sensor;

[0092] When the ambient temperature is lower than the preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management time is less than or equal to the preset time threshold, it is determined that the battery is in a low temperature environment, and the battery needs to be heated at this time. Since the thermal management system is started at this time, and the liquid cooling plate has a greater impact on the temperature of the second temperature sensor at the initial start of the thermal management system, and the average vehicle speed at this time is larger than the vehicle speed threshold, the battery discharge also has an impact on the first temperature sensor. Therefore, in order to improve the accuracy, the battery cell temperature is determined to be the temperature value detected by the first temperature sensor;

[0093] When the ambient temperature is lower than the preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management time is higher than the time threshold, it is determined that the battery is in a low temperature environment, and the battery needs to be heated at this time. Since the thermal management system is started at this time, and since the thermal management system has been running for a certain period of time, the liquid cooling plate has little effect on the temperature of the second temperature sensor. However, the average vehicle speed at this time is higher than the vehicle speed threshold, so that the battery discharge also has an effect on the first temperature sensor. Therefore, in order to improve the accuracy, the battery cell temperature is determined to be the temperature value detected by the second temperature sensor;

[0094] When the ambient temperature is greater than or equal to the temperature threshold, it is determined that the battery is in a non-low-temperature environment. At this time, the battery does not need to be heated or heating has little effect on the second sensor. The average vehicle speed during driving will cause battery discharge to affect the first temperature sensor. Therefore, in order to improve accuracy, the battery cell temperature is determined to be the temperature value detected by the second temperature sensor.

[0095] It should be noted that, in parking conditions or driving conditions, the initial value of the battery cell temperature when the vehicle is started is determined based on the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor at this time. Specifically, the initial maximum temperature of the battery cell is the maximum value of the temperatures detected by the two types of temperature sensors, and the initial minimum temperature of the battery cell is the minimum value of the temperatures detected by the two types of temperature sensors.

[0096] It should be noted that, in a specific embodiment, the time threshold described in this article is 5 minutes, the current threshold is 120 amperes, the temperature threshold is 10 degrees Celsius, and the vehicle speed threshold is 60 kilometers per hour.

[0097] Another embodiment of the present application further provides a battery management system for a double-layer liquid-cooled battery, wherein the double-layer liquid-cooled battery comprises: a first liquid-cooling plate, a battery module, and a second liquid-cooling plate arranged in a vertical direction, see Figure 5 , the battery management system comprises:

[0098] The first processing module 501 is used to obtain the vehicle operating condition information and the ambient temperature of the battery, wherein the operating condition information includes at least one of a driving condition, a parking condition, a fast charging condition, and a slow charging condition;

[0099] The second processing module 502 is used to determine that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature based on the operating condition information and the ambient temperature, wherein the first temperature sensor is arranged on a battery tab busbar corresponding to an edge battery cell in the battery module, and the second temperature sensor is arranged on the top cover of the middle battery cell in the battery module, in the vertical direction, the battery tab busbar is arranged in the middle part of the top cover of the corresponding battery cell, and the second temperature sensor is arranged between the battery tab busbar and the first liquid cooling plate.

[0100] It should be noted that the battery management system is connected to the first temperature sensor and the second temperature sensor.

[0101] Specifically, in the battery management system as described above, the second processing module includes:

[0102] a first processing unit, configured to determine, when the operating condition information is a slow charging condition and the ambient temperature is greater than or equal to a preset temperature threshold, that the battery cell temperature is a temperature value detected by the first temperature sensor;

[0103] a second processing unit, configured to determine that the battery cell temperature is a temperature value detected by the second temperature sensor when the operating condition information is the driving operating condition or the parking operating condition and the ambient temperature is greater than or equal to the temperature threshold;

[0104] The third processing unit is used to determine that the battery cell temperature is the temperature value detected by the first temperature sensor when the operating condition information is the parking condition and the ambient temperature is less than the temperature threshold.

[0105] Furthermore, in the battery management system as described above, the second processing module further includes:

[0106] a fourth processing unit, configured to obtain corresponding reference information according to the operating condition information and the ambient temperature;

[0107] A fifth processing unit is used to determine, according to the operating condition information, the ambient temperature and the reference information, that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature.

[0108] Further, in the battery management system as described above, the fourth processing unit includes:

[0109] A first sub-processing unit is configured to obtain, when the operating condition information is the fast charging operating condition and the ambient temperature is less than the temperature threshold, the reference information being the thermal management time and the charging current of the thermal management system;

[0110] a second sub-processing unit, configured to, when the operating condition information is the fast charging operating condition and the ambient temperature is greater than or equal to the temperature threshold, obtain the reference information including at least the charging current;

[0111] a third sub-processing unit, configured to, when the operating condition information is the slow charging operating condition and the ambient temperature is less than the temperature threshold, obtain the reference information as the thermal management time;

[0112] The fourth sub-processing unit is used to obtain the reference information as the average vehicle speed and / or the thermal management time within a preset time when the operating condition information is the driving condition and the ambient temperature is less than the temperature threshold.

[0113] Specifically, in the battery management system as described above, when the operating condition information is the fast charging operating condition, the fifth processing unit includes:

[0114] a fifth sub-processing unit, configured to determine that the battery cell temperature is a temperature value detected by the first temperature sensor when the ambient temperature is less than a preset temperature threshold and the thermal management time is less than a preset time threshold;

[0115] a sixth sub-processing unit, configured to determine that the battery cell temperature is a temperature value detected by the first temperature sensor when the ambient temperature is lower than the temperature threshold, the thermal management time is greater than or equal to the time threshold, and the charging current is lower than or equal to a preset current threshold;

[0116] a seventh sub-processing unit, configured to determine that the battery cell temperature is a temperature value detected by the second temperature sensor when the ambient temperature is lower than the temperature threshold, the thermal management time is greater than or equal to the time threshold, and the charging current is greater than the current threshold;

[0117] an eighth sub-processing unit, configured to determine that the battery cell temperature is a temperature value detected by the second temperature sensor when the ambient temperature is greater than or equal to the temperature threshold and the charging current is greater than the current threshold;

[0118] A ninth sub-processing unit is configured to determine that the battery cell temperature is a temperature value detected by the first temperature sensor when the ambient temperature is greater than or equal to the temperature threshold and the charging current is less than or equal to the current threshold.

[0119] Specifically, in the battery management system as described above, when the operating condition information is the slow charging operating condition, the fifth processing unit includes:

[0120] an eleventh sub-processing unit, configured to determine that the battery cell temperature is a temperature value detected by the second temperature sensor when the ambient temperature is lower than a preset temperature threshold and the thermal management time is greater than or equal to a preset time threshold;

[0121] an eleventh sub-processing unit, configured to determine that the battery cell temperature is a temperature value detected by the first temperature sensor when the ambient temperature is less than the temperature threshold and the thermal management time is less than the time threshold;

[0122] A twelfth sub-processing unit is configured to determine that the battery cell temperature is a temperature value detected by the first temperature sensor when the ambient temperature is greater than or equal to the temperature threshold.

[0123] Specifically, in the battery management system as described above, when the operating condition information is the driving operating condition, the fifth processing unit includes:

[0124] a thirteenth sub-processing unit, configured to determine that the battery cell temperature is a temperature value detected by the first temperature sensor when the ambient temperature is lower than a preset temperature threshold and the average vehicle speed is lower than or equal to a preset vehicle speed threshold;

[0125] a fourteenth sub-processing unit, configured to determine that the battery cell temperature is a temperature value detected by the second temperature sensor when the ambient temperature is lower than a preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management system is not started;

[0126] a fifteenth sub-processing unit, configured to determine that the battery cell temperature is a temperature value detected by the first temperature sensor when the ambient temperature is lower than a preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management time is lower than or equal to a preset time threshold;

[0127] a sixteenth sub-processing unit, configured to determine that the battery cell temperature is a temperature value detected by the second temperature sensor when the ambient temperature is lower than a preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management time is higher than the time threshold;

[0128] A seventeenth sub-processing unit is configured to determine that the battery cell temperature is a temperature value detected by the second temperature sensor when the ambient temperature is greater than or equal to the temperature threshold.

[0129] The battery management system of the present application is a system corresponding to an embodiment of the above-mentioned method for determining the cell temperature of a double-layer liquid-cooled battery. All implementation means in the above-mentioned method embodiment are applicable to the embodiment of the system and can achieve the same technical effect.

[0130] Another embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the computer program implements the steps of a method for determining the temperature of a battery cell of a double-layer liquid-cooled battery as described above.

[0131] Yet another embodiment of the present application provides a vehicle, comprising: the battery management system as described above.

[0132] The vehicle provided in the present application includes the above-mentioned battery management system, so that the vehicle can be correctly controlled based on the accurate battery cell temperature during use, which is conducive to improving user experience.

[0133] In addition, the present application may repeat reference numerals and / or letters in different examples. This repetition is for the purpose of simplicity and clarity, and does not in itself indicate the relationship between the various embodiments and / or settings discussed.

[0134] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusions.

[0135] The above is a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles described in the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for determining the temperature of a battery cell of a double-layer liquid-cooled battery, the double-layer liquid-cooled battery comprising: A first liquid cooling plate, a battery module and a second liquid cooling plate are arranged in a vertical direction, wherein the method comprises: Acquire operating condition information of the vehicle and the ambient temperature of the battery, wherein the operating condition information includes at least one of a driving condition, a parking condition, a fast charging condition, and a slow charging condition; According to the working condition information and the ambient temperature, determine that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature, wherein the first temperature sensor is arranged on a battery tab busbar corresponding to an edge battery cell in the battery module, and the second temperature sensor is arranged on a top cover of a middle battery cell in the battery module, in the vertical direction, the battery tab busbar is arranged in the middle part of the top cover of the corresponding battery cell, and the second temperature sensor is arranged between the battery tab busbar and the first liquid cooling plate; The determining, according to the operating condition information and the ambient temperature, that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature, further includes: According to the working condition information and the ambient temperature, corresponding reference information is obtained, wherein the reference information includes: a thermal management time of the thermal management system, a charging current, and an average vehicle speed within a preset time; Determine, according to the operating condition information, the ambient temperature, and the reference information, that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature.

2. The method according to claim 1, characterized in that The determining, according to the operating condition information and the ambient temperature, that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature includes: When the operating condition information is a slow charging condition and the ambient temperature is greater than or equal to a preset temperature threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor; When the operating condition information is the driving operating condition or the parking operating condition, and the ambient temperature is greater than or equal to the temperature threshold, determining that the battery cell temperature is a temperature value detected by the second temperature sensor; When the operating condition information is the parking condition and the ambient temperature is less than the temperature threshold, it is determined that the battery cell temperature is a temperature value detected by the first temperature sensor.

3. The method according to claim 2, characterized in that According to the operating condition information and the ambient temperature, corresponding reference information is obtained, including: When the operating condition information is the fast charging operating condition and the ambient temperature is less than the temperature threshold, the reference information obtained is the thermal management time and the charging current of the thermal management system; When the operating condition information is the fast charging operating condition and the ambient temperature is greater than or equal to the temperature threshold, the reference information obtained includes at least the charging current; When the operating condition information is the slow charging operating condition and the ambient temperature is less than the temperature threshold, the reference information obtained is the thermal management time; When the operating condition information is the driving operating condition and the ambient temperature is less than the temperature threshold, the reference information obtained is the average vehicle speed within a preset time and / or the thermal management time.

4. The method according to claim 3, characterized in that When the operating condition information is the fast charging operating condition, determining the temperature value detected by the first temperature sensor or the second temperature sensor as the battery cell temperature according to the operating condition information, the ambient temperature, and the reference information includes: When the ambient temperature is less than a preset temperature threshold and the thermal management time is less than a preset time threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor; When the ambient temperature is lower than the temperature threshold, the thermal management time is greater than or equal to the time threshold, and the charging current is less than or equal to a preset current threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor; When the ambient temperature is lower than the temperature threshold, the thermal management time is greater than or equal to the time threshold, and the charging current is greater than the current threshold, determining that the battery cell temperature is a temperature value detected by the second temperature sensor; When the ambient temperature is greater than or equal to the temperature threshold and the charging current is greater than the current threshold, determining that the battery cell temperature is a temperature value detected by the second temperature sensor; When the ambient temperature is greater than or equal to the temperature threshold and the charging current is less than or equal to the current threshold, it is determined that the battery cell temperature is a temperature value detected by the first temperature sensor.

5. The method according to claim 3, characterized in that: When the operating condition information is the slow charging operating condition, determining the temperature value detected by the first temperature sensor or the second temperature sensor as the battery cell temperature according to the operating condition information, the ambient temperature, and the reference information includes: When the ambient temperature is lower than a preset temperature threshold and the thermal management time is greater than or equal to a preset time threshold, determining that the battery cell temperature is a temperature value detected by the second temperature sensor; When the ambient temperature is less than the temperature threshold and the thermal management time is less than the time threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor; When the ambient temperature is greater than or equal to the temperature threshold, it is determined that the battery core temperature is a temperature value detected by the first temperature sensor.

6. The method according to claim 3, characterized in that In a case where the operating condition information is the driving operating condition, determining, according to the operating condition information, the ambient temperature, and the reference information, that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature, includes: When the ambient temperature is less than a preset temperature threshold and the average vehicle speed is less than or equal to a preset vehicle speed threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor; When the ambient temperature is lower than a preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management system is not started, determining that the battery cell temperature is a temperature value detected by the second temperature sensor; When the ambient temperature is lower than a preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management time is lower than or equal to a preset time threshold, determining that the battery cell temperature is a temperature value detected by the first temperature sensor; When the ambient temperature is lower than a preset temperature threshold, the average vehicle speed is higher than the vehicle speed threshold, and the thermal management time is higher than the time threshold, determining that the battery cell temperature is a temperature value detected by the second temperature sensor; When the ambient temperature is greater than or equal to the temperature threshold, it is determined that the battery cell temperature is a temperature value detected by the second temperature sensor.

7. A battery management system for a double-layer liquid-cooled battery, the double-layer liquid-cooled battery comprising: A first liquid cooling plate, a battery module and a second liquid cooling plate are arranged in a vertical direction, wherein the battery management system comprises: A first processing module is used to obtain the operating condition information of the vehicle and the ambient temperature of the battery, wherein the operating condition information includes at least one of a driving condition, a parking condition, a fast charging condition, and a slow charging condition; a second processing module, for determining, according to the operating condition information and the ambient temperature, that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature, wherein the first temperature sensor is arranged on a battery tab busbar corresponding to an edge battery cell in the battery module, and the second temperature sensor is arranged on a top cover of a middle battery cell in the battery module, in the vertical direction, the battery tab busbar is arranged in the middle part of the top cover of the corresponding battery cell, and the second temperature sensor is arranged between the battery tab busbar and the first liquid cooling plate; The determining, according to the operating condition information and the ambient temperature, that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature, further includes: According to the working condition information and the ambient temperature, corresponding reference information is obtained, wherein the reference information includes: a thermal management time of the thermal management system, a charging current, and an average vehicle speed within a preset time; Determine, according to the operating condition information, the ambient temperature, and the reference information, that the temperature value detected by the first temperature sensor or the second temperature sensor is the battery cell temperature.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the computer program implements the steps of a method for determining the temperature of a battery cell of a double-layer liquid-cooled battery according to any one of claims 1 to 6.

9. A vehicle, characterized in that: include: The battery management system as claimed in claim 7.

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