Evaluation and optimization method and device of power battery thermal management system and storage medium

Abstract

This invention provides an evaluation and optimization method, device, and storage medium for a power battery thermal management system, belonging to the field of battery thermal management technology. The method includes the following steps: acquiring temperature data of the power battery under various test conditions; comparing each temperature data point with a pre-set optimal operating temperature range threshold to obtain temperature difference data under each test condition; determining the weight of each test condition based on the mapping relationship between each test condition and its pre-set weights; and determining the temperature deviation data of the power battery based on the temperature difference data and the weights of each test condition. A higher temperature deviation indicates a lower ability of the power battery to operate within its optimal operating temperature range, and vice versa, thus evaluating the power battery's ability to operate within its optimal operating temperature range.

Description

Technical Field

[0001] This invention relates to the field of battery thermal management technology, and in particular to the evaluation, optimization methods, equipment and storage media of power battery thermal management systems. Background Technology

[0002] As a core component of electric vehicles, the charging and power performance of the battery varies significantly with temperature. This is due to the battery's inherent characteristics; temperature affects its internal resistance during charging and discharging, as well as its maximum permissible charging and discharging current. Given my country's vast territory and wide latitude, the average annual temperature varies considerably across different regions. Therefore, electric vehicles used domestically need to possess high temperature adaptability, which poses a significant challenge to the battery.

[0003] To ensure that the power battery can perform well under different temperature conditions and meet the user's needs for charging, driving, and discharging, it is necessary to adopt a method to maintain the power battery temperature within the optimal operating range when the electric vehicle is running in different ambient temperatures. The power battery thermal management system is a subsystem within the power battery that achieves this function. It regulates the power battery temperature through heating, cooling, and temperature equalization, with the goal of keeping the power battery within its optimal operating range at all times.

[0004] However, current electric vehicle power battery product development focuses only on meeting the charging and discharging performance requirements of the power battery, neglecting the need to ensure the power battery temperature remains within its optimal operating temperature range. Patent application CN104810572A discloses a power battery thermal management design method, outlining a control strategy to adjust the operating mode according to battery temperature changes. However, in reality, when the power battery operates outside its optimal operating temperature range, capacity degradation accelerates, internal side reactions intensify, and safety risks increase. These factors severely impact the health and safety of the power battery throughout its entire lifespan. Summary of the Invention

[0005] The purpose of this invention is to provide a method, device, and storage medium for evaluating and optimizing a power battery thermal management system, in order to solve the problem in the prior art that it is difficult to evaluate the ability of a power battery to operate within its optimal operating temperature range.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] An evaluation method for a power battery thermal management system includes the following steps:

[0008] Acquire temperature data of the power battery under various test conditions;

[0009] Each of the temperature data is compared with a pre-set optimal operating temperature range threshold to obtain the difference temperature data under each of the test conditions. Based on each of the test conditions and the pre-set mapping relationship between the test conditions and weights, the weight of each of the test conditions is determined.

[0010] Based on the temperature difference data of each test condition and the weight of each test condition, the temperature deviation data of the power battery is determined in order to evaluate the thermal management system of the power battery.

[0011] Optionally, the test conditions include temperature conditions and usage conditions, and each of the test conditions is obtained by combining the temperature conditions and the usage conditions.

[0012] Optionally, the temperature conditions include at least one of high temperature environment, normal temperature environment, low temperature environment and low temperature environment; the usage conditions include at least one of charging and discharging.

[0013] Optionally, the threshold value of the optimal operating temperature range is 25℃~35℃.

[0014] Optionally, the temperature data includes multiple temperature values ​​collected at a preset frequency within a preset time period.

[0015] Optionally, the temperature difference data is the average of the differences between each temperature value and the threshold of the optimal working temperature range within the preset time period, or the temperature difference data is the standard deviation of the differences between each temperature value and the threshold of the optimal working temperature range within the preset time period.

[0016] An evaluation system for a power battery thermal management system, comprising:

[0017] The data acquisition module is used to acquire temperature data of the power battery under various test conditions;

[0018] The analysis and calculation module compares each of the temperature data with a pre-set optimal operating temperature range threshold to obtain the difference temperature data under each of the test conditions, and determines the weight of each of the test conditions based on each of the test conditions and the pre-set mapping relationship between the test conditions and weights.

[0019] The evaluation module determines the temperature deviation data of the power battery based on the temperature difference data of each test condition and the weight of each test condition, so as to evaluate the thermal management system of the power battery.

[0020] An optimization method for a power battery thermal management system includes the following steps:

[0021] Acquire temperature data of the power battery under various test conditions;

[0022] Each of the temperature data is compared with a pre-set optimal operating temperature range threshold to obtain the temperature difference data under each of the test conditions.

[0023] Based on each of the test conditions and the pre-set mapping relationship between the test conditions and weights, the weight of each of the test conditions is determined, and the temperature deviation data of the power battery is determined according to the temperature difference data of each of the test conditions and the weight of each test condition.

[0024] The temperature deviation data is compared with a preset stop threshold. If the temperature deviation data is greater than the stop threshold, the thermal management system of the power battery is adjusted until the temperature deviation data is less than or equal to the stop threshold.

[0025] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program to implement the steps of the evaluation method for a power battery thermal management system as described above.

[0026] A computer-readable storage medium storing a computer program, characterized in that, when executed by a processor, the computer program implements the steps of the evaluation method for the power battery thermal management system as described above.

[0027] The beneficial effects of this invention are as follows: This invention compares each temperature data point with a pre-set optimal operating temperature range threshold, and based on each test condition and the pre-set mapping relationship between the test conditions and their weights, obtains the differential temperature data under each test condition and the weights of each test condition. Then, based on the differential temperature data under each test condition and the weights of each test condition, it determines the temperature deviation data of the power battery. The temperature deviation data can be used to evaluate the thermal management system of the power battery. The higher the temperature deviation data, the worse the power battery's ability to maintain operation within the optimal operating temperature range; conversely, the lower the temperature deviation data, the better the power battery's ability to maintain operation within the optimal operating temperature range. This achieves the evaluation of the power battery's ability to maintain operation within the optimal operating temperature range. Attached Figure Description

[0028] Figure 1 This is a flowchart of the evaluation method for the power battery thermal management system in an embodiment of the present invention;

[0029] Figure 2This is a structural block diagram of the evaluation device for the power battery thermal management system in an embodiment of the present invention;

[0030] Figure 3 This is a flowchart illustrating the optimization of the power battery thermal management system in an embodiment of the present invention.

[0031] Figure 4 This is a schematic diagram of the structure of a computer system suitable for implementing the electronic device of the present application. Detailed Implementation

[0032] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0033] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0034] like Figure 1 As shown, this embodiment provides an evaluation method for a power battery thermal management system, including the following steps:

[0035] S10: Acquire temperature data of the power battery under various test conditions;

[0036] S20: Compare each of the temperature data with a pre-set optimal operating temperature range threshold to obtain the difference temperature data under each of the test conditions, and determine the weight of each of the test conditions based on each of the test conditions and the pre-set mapping relationship between the test conditions and weights.

[0037] S30: Based on the temperature difference data of each test condition and the weight of each test condition, determine the temperature deviation data of the power battery in order to evaluate the thermal management system of the power battery.

[0038] In this embodiment, by comparing each temperature data point with a pre-set optimal operating temperature range threshold, and based on each test condition and the pre-set mapping relationship between the test conditions and weights, the differential temperature data under each test condition and the weight of each test condition are obtained. Then, based on the differential temperature data under each test condition and the weight of each test condition, the temperature deviation data of the power battery is determined. The temperature deviation data can be used to evaluate the thermal management system of the power battery. The higher the temperature deviation data, the worse the power battery's ability to operate within the optimal operating temperature range; conversely, the lower the temperature deviation data, the better the power battery's ability to operate within the optimal operating temperature range. This achieves the evaluation of the power battery's ability to operate within the optimal operating temperature range.

[0039] In some embodiments, the test conditions include temperature conditions and usage conditions, and each of the test conditions is obtained by combining the temperature conditions and the usage conditions.

[0040] Specifically, the temperature conditions include at least one of high-temperature environment, normal-temperature environment, lower-temperature environment, and low-temperature environment; the usage conditions include at least one of charging and discharging. In this embodiment, the low-temperature environment is below -5℃, the lower-temperature environment is below -5℃ to 25℃, the normal-temperature environment is 25℃ to 35℃, and the high-temperature environment is above 35℃. The temperature conditions can be reasonably selected according to the actual situation. The optimal operating temperature range threshold is a temperature range. When the temperature of the power battery meets the optimal operating temperature range threshold, the power battery performs well and effectively extends the service life of the power battery. The optimal operating temperature range threshold can be reasonably set according to the actual situation of the power battery. In this embodiment, the optimal operating temperature range threshold is 25℃ to 35℃.

[0041] In this embodiment, the temperature data includes multiple temperature values ​​collected at a preset frequency within a preset time period. The preset time is the test time, which means that the temperature of the power battery is collected at a preset frequency within the test time to obtain multiple temperature values. Therefore, in this embodiment, the differential temperature data is the average of the differences between each temperature value and the optimal operating temperature range threshold within the preset time period, or the differential temperature data is the standard deviation of the differences between each temperature value and the optimal operating temperature range threshold within the preset time period. The use of standard deviation or average value can be selected according to the evaluation focus.

[0042] like Figure 2 As shown, this embodiment also provides an evaluation system for a power battery thermal management system, including:

[0043] The data acquisition module is used to acquire temperature data of the power battery under various test conditions;

[0044] The analysis and calculation module compares each of the temperature data with a pre-set optimal operating temperature range threshold to obtain the difference temperature data under each of the test conditions, and determines the weight of each of the test conditions based on each of the test conditions and the pre-set mapping relationship between the test conditions and weights.

[0045] The evaluation module determines the temperature deviation data of the power battery based on the temperature difference data of each test condition and the weight of each test condition, so as to evaluate the thermal management system of the power battery.

[0046] This embodiment also provides an optimization method for a power battery thermal management system, including the following steps:

[0047] Acquire temperature data of the power battery under various test conditions;

[0048] Each of the temperature data is compared with a pre-set optimal operating temperature range threshold to obtain the temperature difference data under each of the test conditions.

[0049] Based on each of the test conditions and the pre-set mapping relationship between the test conditions and weights, the weight of each of the test conditions is determined, and the temperature deviation data of the power battery is determined according to the temperature difference data of each of the test conditions and the weight of each test condition.

[0050] The temperature deviation data is compared with a preset stop threshold. If the temperature deviation data is greater than the stop threshold, the thermal management system of the power battery is adjusted until the temperature deviation data is less than or equal to the stop threshold.

[0051] like Figure 3 As shown, in practice, optimizing the thermal management system of a power battery includes the following steps:

[0052] (1) The operating temperature range of the power battery is preset, that is, the temperature conditions are divided. According to the ambient temperature of the actual use area of ​​the power battery, the temperature conditions are divided into low temperature, lower temperature, normal temperature and high temperature. For example, -15℃ is low temperature, 0℃ is lower temperature, 25℃ is normal temperature and 40℃ is high temperature. The normal temperature should be within the suitable operating temperature range of the power battery, that is, meet the threshold of the optimal operating temperature range.

[0053] (2) The operating conditions of the power battery thermal management system are set. Based on the different operating conditions of the vehicle and the participation of the power battery thermal management system, the operating conditions of the power battery are divided into charging and discharging. Charging is divided into DC charging and AC charging, and discharging can be divided into simulated vehicle comprehensive operating condition discharge and simulated vehicle high-speed operating condition discharge, such as a vehicle speed of 100km / h for 10 minutes. The specific operating condition type varies depending on the type of vehicle power system.

[0054] (3) Test the operating temperature performance of the power battery under the thermal management system at different temperatures and operating conditions, and record the power battery temperature curve.

[0055] (4) Set the range of the optimal operating temperature of the power battery, that is, the threshold of the optimal operating temperature range is [T1, T2]. In this embodiment, T1 is 25°C and T2 is 35°C.

[0056] (5) Calculate the deviation of the power battery temperature T from the optimal operating temperature range under different temperature conditions and test conditions to obtain the difference temperature data. If the power battery temperature T is higher than T2, the deviation value is recorded as (T-T2); if the power battery temperature T is lower than T1, the deviation value is recorded as (T1-T); if the power battery temperature is between T1 and T2, the deviation value is recorded as 0. In this embodiment, the deviation value of the power battery is recorded in 1 second units throughout the entire test process, and the average value ΔT of the deviation value of the power battery over the entire test condition time scale and the standard deviation s of the deviation value of the power battery over the time scale are calculated. The average value ΔT and the standard deviation s of the deviation value of the power battery are used together to evaluate the power battery. For the thermal management system of the power battery, the smaller the average value ΔT, the higher the proportion of time the power battery works within the optimal operating temperature range; the smaller the standard deviation s, the smaller the fluctuation of the power battery working outside the optimal operating temperature range.

[0057] (6) There are differences in the ΔT calculated for different temperatures and different operating conditions. In order to comprehensively evaluate the performance of the power battery thermal management system in the full temperature range and full usage conditions, different weights are set for different temperature conditions and different usage conditions. The actual weights can be allocated with reference to the temperature distribution of the target usage area of ​​the power battery and the design usage condition distribution of the vehicle. The sum of the weights of all test conditions is 100%.

[0058] (7) According to the weight of each test condition, the mean temperature deviation of the power battery and the standard deviation of the power battery temperature deviation are weighted and summed to obtain the temperature deviation data of the power battery. The minimum temperature deviation data of the power battery is taken as the optimization target of the power battery thermal management system. The power battery thermal management scheme is adjusted until the temperature deviation data of the power battery reaches the pre-set design target, that is, the stopping threshold, to obtain the best design scheme of the power battery thermal management system.

[0059] Since power batteries have an optimal operating temperature, their performance degrades significantly when the actual temperature deviates from this optimal temperature. Therefore, the goal of a power battery thermal management system is to control the battery temperature to ensure optimal performance; in other words, to maintain the battery at its optimal operating temperature under different ambient temperatures. Temperature regulation capability is a manifestation of this goal of the power battery thermal management system. Ideally, the operating curve of the power battery, i.e., temperature-SOC, should remain consistent under all ambient temperature conditions. However, under real-world conditions, due to the hysteresis and dissipation effects inherent in the power battery thermal management system, maintaining a consistent operating curve across all ambient temperature conditions is difficult to achieve. Therefore, this embodiment evaluates the temperature regulation capability of the thermal management system by assessing the degree of deviation of the actual power battery thermal management system from its ideal operating target.

[0060] This embodiment also provides an electronic device, including: one or more processors; and a storage device for storing one or more programs, which, when executed by the one or more processors, enable the electronic device to perform the evaluation of the power battery thermal management system provided in the above embodiments.

[0061] Figure 4 A schematic diagram of a computer system suitable for implementing this embodiment of the electronic device is shown. It should be noted that... Figure 4 The computer system 1200 of the electronic device shown is merely an example and should not impose any limitation on the functionality and scope of use of this embodiment.

[0062] like Figure 4As shown, the computer system 1200 includes a Central Processing Unit (CPU) 1201, which can perform various appropriate actions and processes based on programs stored in Read-Only Memory (ROM) 1202 or programs loaded from storage portion 1208 into Random Access Memory (RAM) 1203, such as performing the methods described in the above embodiments. Various programs and data required for system operation are also stored in RAM 1203. The CPU 1201, ROM 1202, and RAM 1203 are interconnected via bus 1204. An Input / Output (I / O) interface 1205 is also connected to bus 1204.

[0063] The following components are connected to I / O interface 1205: an input section 1206 including a keyboard, mouse, etc.; an output section 1207 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 1208 including a hard disk, etc.; and a communication section 1209 including a network interface card such as a LAN (Local Area Network) card, modem, etc. The communication section 1209 performs communication processing via a network such as the Internet. A drive 1210 is also connected to I / O interface 1205 as needed. Removable media 1211, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., are installed on drive 1210 as needed so that computer programs read from them can be installed into storage section 1208 as needed.

[0064] Specifically, according to embodiments of this embodiment, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this embodiment include a computer program product comprising a computer program carried on a computer-readable medium, the computer program including a computer program for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 1209, and / or installed from removable medium 1211. When the computer program is executed by the central processing unit (CPU) 1201, it performs various functions defined in the system of this embodiment.

[0065] It should be noted that the computer-readable medium shown in this embodiment can be a computer-readable signal medium, a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying a computer-readable computer program. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media can also be any computer-readable medium other than computer-readable storage media, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0066] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this embodiment. Each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, or they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0067] The units described in this embodiment can be implemented in software or hardware, and can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0068] Another aspect of this embodiment provides a computer-readable storage medium storing a computer program that, when executed by a computer's processor, causes the computer to perform an evaluation as described in the previous power battery thermal management system. This computer-readable storage medium may be included in the electronic device described in the above embodiments, or it may exist independently and not incorporated into the electronic device.

[0069] Another aspect of this embodiment provides a computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the evaluation of the power battery thermal management system provided in the various embodiments described above.

[0070] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

[0071] The above embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention.

Claims

1. An evaluation method for a power battery thermal management system, characterized in that, Includes the following steps: Acquire temperature data of the power battery under various test conditions; Each of the temperature data is compared with a pre-set optimal operating temperature range threshold to obtain the temperature difference data under each test condition. Based on each of the test conditions and the pre-set mapping relationship between the test conditions and weights, the weight of each of the test conditions is determined. Based on the temperature difference data of each test condition and the weight of each test condition, the temperature deviation data of the power battery is determined in order to evaluate the thermal management system of the power battery. The temperature data includes multiple temperature values ​​collected at a preset frequency within a preset time period. The differential temperature data is the average of the differences between each temperature value and the optimal operating temperature range threshold within the preset time period, or the differential temperature data is the standard deviation of the differences between each temperature value and the optimal operating temperature range threshold within the preset time period.

2. The evaluation method for the power battery thermal management system according to claim 1, characterized in that, The test conditions include temperature conditions and usage conditions, and each of the test conditions is obtained by combining the temperature conditions and the usage conditions.

3. The evaluation method for the power battery thermal management system according to claim 2, characterized in that, The temperature conditions include at least one of high temperature environment, normal temperature environment, low temperature environment and low temperature environment; the usage conditions include at least one of charging and discharging.

4. The evaluation method for the power battery thermal management system according to claim 1, characterized in that, The optimal operating temperature range threshold is 25℃~35℃.

5. An evaluation system for a power battery thermal management system, characterized in that, include: The data acquisition module is used to acquire temperature data of the power battery under various test conditions; The analysis and calculation module compares each of the temperature data with a pre-set optimal operating temperature range threshold to obtain the temperature difference data under each test condition, and determines the weight of each test condition based on each test condition and the pre-set mapping relationship between the test conditions and weights. The evaluation module determines the temperature deviation data of the power battery based on the temperature difference data of each test condition and the weight of each test condition, so as to evaluate the thermal management system of the power battery. The temperature data includes multiple temperature values ​​collected at a preset frequency within a preset time period. The differential temperature data is the average of the differences between each temperature value and the optimal operating temperature range threshold within the preset time period, or the differential temperature data is the standard deviation of the differences between each temperature value and the optimal operating temperature range threshold within the preset time period.

6. An optimization method for a power battery thermal management system, characterized in that, Includes the following steps: Acquire temperature data of the power battery under various test conditions; Each of the temperature data points is compared with a pre-set optimal operating temperature range threshold to obtain the temperature difference data under each test condition. Based on each of the test conditions and the pre-set mapping relationship between the test conditions and weights, the weight of each of the test conditions is determined, and the temperature deviation data of the power battery is determined according to the temperature difference data of each of the test conditions and the weight of each test condition. The temperature deviation data is compared with a preset stop threshold. If the temperature deviation data is greater than the stop threshold, the thermal management system of the power battery is adjusted until the temperature deviation data is less than or equal to the stop threshold. The temperature data includes multiple temperature values ​​collected at a preset frequency within a preset time period. The differential temperature data is the average of the differences between each temperature value and the optimal operating temperature range threshold within the preset time period, or the differential temperature data is the standard deviation of the differences between each temperature value and the optimal operating temperature range threshold within the preset time period.

7. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the evaluation method for the power battery thermal management system as described in any one of claims 1 to 4.

8. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the evaluation method for the power battery thermal management system as described in any one of claims 1 to 4.

Images