Method and device for testing internal temperature of battery and medium

Abstract

The invention discloses a battery internal temperature testing method and device and a medium. The battery internal temperature testing method comprises the following steps: acquiring the current AC internal resistance of a target battery; based on a preset association relationship, determining a battery internal temperature associated with the current AC internal resistance, the preset association relationship representing an association relationship between a plurality of preset AC internal resistances and a plurality of preset battery internal temperatures; and taking the battery internal temperature associated with the current AC internal resistance as the current battery internal temperature of the target battery. According to the association relationship between the AC internal resistance and the battery internal temperature, the battery internal temperature associated with the current AC internal resistance of the target battery is determined and serves as the current battery internal temperature of the target battery, so that the testing cost of the battery internal temperature is reduced, and the testing accuracy of the battery internal temperature is improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a method, device and medium for testing the internal temperature of a battery. Background Art

[0002] In the related art, if you want to determine the internal temperature of the battery, you generally need to embed a temperature sensor inside the battery during the battery production stage to use the sensor to measure the internal temperature of the battery, but this method is costly. For batteries that have already been produced, if the temperature of the battery surface is used to infer or approximately replace the internal temperature of the battery cell, the accuracy of the internal temperature of the battery cell is low and cannot meet actual needs.

[0003] It can be seen that the current battery internal temperature testing solution cannot take into account both testing cost and testing accuracy. Summary of the invention

[0004] The embodiments of the present application provide a method, device and medium for testing the internal temperature of a battery, aiming to reduce the testing cost of the internal temperature of a battery and improve the testing accuracy of the internal temperature of a battery.

[0005] In one aspect, the present application provides a method for testing the internal temperature of a battery, the method comprising:

[0006] Get the current AC internal resistance of the target battery;

[0007] Based on a preset correlation relationship, determining the battery internal temperature associated with the current AC internal resistance, wherein the preset correlation relationship represents a correlation relationship between a plurality of preset AC internal resistances and a plurality of preset battery internal temperatures;

[0008] The battery internal temperature associated with the current AC internal resistance is used as the current battery internal temperature of the target battery.

[0009] In some embodiments, the determining the battery internal temperature associated with the current AC internal resistance based on a preset association relationship includes:

[0010] Acquire a current internal resistance change rate of the current AC internal resistance relative to a first preset standard AC internal resistance;

[0011] Based on the preset association relationship, the battery internal temperature associated with the current internal resistance change rate is determined, wherein the preset association relationship represents the association between multiple preset internal resistance change rates and multiple preset battery internal temperatures, and each preset internal resistance change rate is determined based on one preset AC internal resistance.

[0012] In some embodiments, before obtaining the current internal resistance change rate of the current AC internal resistance relative to the first preset standard AC internal resistance, the following method may also be included:

[0013] Placing the target battery in an environment with a preset standard temperature;

[0014] The AC internal resistance of the target battery in the environment of the preset standard temperature is obtained and used as the first preset standard AC internal resistance.

[0015] In some embodiments, before obtaining the current AC internal resistance of the target battery, the following steps may also be included:

[0016] Place the preset battery in an environment with a preset test temperature;

[0017] Acquire the AC internal resistance of the preset battery in the environment of the preset test temperature and use it as the preset AC internal resistance, and use the preset test temperature as the preset battery internal temperature to obtain a correlation relationship between the preset AC internal resistance and the preset battery internal temperature;

[0018] The preset association relationship is generated based on the association relationships between the plurality of preset AC internal resistances and the plurality of preset battery internal temperatures.

[0019] In some embodiments, generating the preset association relationship based on the association relationship between the plurality of preset AC internal resistances and the plurality of preset battery internal temperatures includes:

[0020] Obtaining an internal resistance change rate of each of the preset AC internal resistances relative to a second preset standard AC internal resistance as a preset internal resistance change rate, and obtaining a correlation relationship between the preset internal resistance change rate and a preset battery internal temperature;

[0021] The preset correlation relationship is generated based on the correlation relationship between the plurality of preset internal resistance change rates and the plurality of preset battery internal temperatures.

[0022] In some embodiments, the method for testing the internal temperature of the battery further includes:

[0023] Place the preset battery in an environment with a preset standard temperature;

[0024] Acquire a historical state of charge and a historical AC internal resistance of the preset battery in an environment of the preset standard temperature, and obtain a correlation relationship between the historical state of charge and the historical AC internal resistance;

[0025] Determining the influence of the historical state of charge on the historical AC internal resistance based on the correlation between the historical state of charge and the historical AC internal resistance;

[0026] If the impact degree meets the preset low impact condition, the step of obtaining the current AC internal resistance of the target battery is performed.

[0027] In some embodiments, the determining the battery internal temperature associated with the current AC internal resistance based on a preset association relationship includes:

[0028] Obtaining a current state of charge of the target battery;

[0029] Correcting the current AC internal resistance based on the current state of charge;

[0030] Based on the preset association relationship, a corrected battery internal temperature associated with the current AC internal resistance is determined and used as the battery internal temperature associated with the current AC internal resistance.

[0031] In some embodiments, after obtaining the current AC internal resistance of the target battery, the following steps may also be performed:

[0032] Determining a current state of the current AC internal resistance;

[0033] If the current AC internal resistance is currently in a stable state, the step of determining the internal temperature of the battery associated with the current AC internal resistance based on the preset association relationship is performed.

[0034] On the other hand, an embodiment of the present application provides a battery internal temperature testing device, comprising:

[0035] An acquisition module, used to acquire the current AC internal resistance of the target battery;

[0036] A determination module, configured to determine the battery internal temperature associated with the current AC internal resistance based on a preset association relationship, wherein the preset association relationship represents an association relationship between a plurality of preset AC internal resistances and a plurality of preset battery internal temperatures;

[0037] The processing module is used to use the battery internal temperature associated with the current AC internal resistance as the current battery internal temperature of the target battery.

[0038] On the other hand, the present application also provides a computer device, the computer device comprising:

[0039] one or more processors;

[0040] Memory; and

[0041] One or more application programs, wherein the one or more application programs are stored in the memory and configured to be executed by the processor to implement the steps of any one of the methods for testing the internal temperature of a battery.

[0042] On the other hand, the present application further provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program is loaded by a processor to execute the steps in any one of the battery internal temperature testing methods.

[0043] On the other hand, the present application further provides a computer program product, including a computer program or instructions, wherein the computer program or instructions are executed by a processor to implement the method for testing the internal temperature of a battery as described in any one of the above items.

[0044] The embodiments of the present application provide a method, device and medium for testing the internal temperature of a battery. The method for testing the internal temperature of a battery includes: obtaining the current AC internal resistance of the target battery; determining the internal temperature of the battery associated with the current AC internal resistance based on a preset correlation relationship, wherein the preset correlation relationship represents the correlation relationship between multiple preset AC internal resistances and multiple preset battery internal temperatures; and using the internal temperature of the battery associated with the current AC internal resistance as the current internal temperature of the target battery. The embodiments of the present application determine the internal temperature of the battery associated with the current AC internal resistance of the target battery based on the correlation relationship between the AC internal resistance and the internal temperature of the battery, and use it as the current internal temperature of the target battery. Compared with the solution of pre-embedded temperature sensors inside the battery, the cost of testing the internal temperature of the battery is lower. Compared with the solution of using the temperature of the battery surface to infer or approximately replace the internal temperature of the battery cell, since the target battery itself can be used as a temperature sensing device, the current AC impedance of the target battery is more sensitive to the current internal temperature of the battery, so the test accuracy of the internal temperature of the battery will also be higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0046] Figure 1 1 is a flow chart of an embodiment of a method for testing the internal temperature of a battery provided in an embodiment of the present application;

[0047] Figure 2 is a schematic diagram of the correlation between multiple preset AC internal resistances and multiple preset battery internal temperatures provided in an embodiment of the present application;

[0048] Figure 3 1 is a flow chart of another embodiment of a method for testing the internal temperature of a battery provided in an embodiment of the present application;

[0049] Figure 4is a schematic diagram of the correlation between multiple preset internal resistance change rates and multiple preset battery internal temperatures provided in an embodiment of the present application;

[0050] Figure 5 1 is a flow chart of another embodiment of a method for testing the internal temperature of a battery provided in an embodiment of the present application;

[0051] Figure 6 It is a schematic diagram of the correlation between the historical state of charge and the historical AC internal resistance provided in the embodiment of the present application.

[0052] Figure 7 1 is a schematic diagram of the structure of an embodiment of a battery internal temperature testing device provided in an embodiment of the present application;

[0053] Figure 8 It is a schematic diagram of the terminal structure of an embodiment of the computer device provided in the embodiments of the present application. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. In the description of the present application, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. In the present application, the term "in some embodiments" is used to indicate "used as an example, illustration or explanation". Any embodiment described as "in some embodiments" in the present application is not necessarily interpreted as being more preferred or more advantageous than other embodiments.

[0055] It should be noted that since the system of the embodiment of the present application is executed in a computer device, the processing objects of each computer device exist in the form of data or information. For example, time is actually time information. It can be understood that if size, quantity, position, etc. are mentioned in subsequent embodiments, they are all corresponding data for processing by the computer device. The details will not be repeated here.

[0056] The embodiments of the present application provide a method, device and medium for testing the internal temperature of a battery, which are described in detail below.

[0057] Reference Figure 1 In one embodiment, the method for testing the internal temperature of a battery includes:

[0058] 101. Obtain the current AC internal resistance of the target battery.

[0059] In the embodiments of the present application, the target battery is a battery that needs to be tested to obtain the current internal temperature of the battery. The target battery can specifically be a lithium-ion battery, a lithium iron phosphate battery, a ternary lithium battery, etc. It can also be a cylindrical battery, a square battery, etc. It can also be a soft-pack battery, a hard-pack battery, etc., which is not limited here.

[0060] Alternating Current Internal Resistance (ACIR) refers to the internal resistance of a battery under the action of alternating current, reflecting the state of the electrochemical reaction. The current AC internal resistance of the target battery can be obtained by testing with relevant instruments. For example, an AC internal resistance tester can be connected to the positive and negative electrodes of the target battery to measure the current AC internal resistance of the target battery.

[0061] In some embodiments of the present application, after obtaining the current AC internal resistance of the target battery, the following may also be included: determining the current state of the current AC internal resistance; if the current AC internal resistance is currently in a stable state, executing step 102 to ensure the accuracy of the current internal temperature of the battery tested. If the current AC internal resistance is not currently in a stable state, step 102 is not executed to save time cost.

[0062] Among them, the method for determining the current state of the current AC internal resistance is illustrated by example. Specifically, determining the current state of the current AC internal resistance may include: determining the internal resistance change information of the current AC internal resistance relative to time change, and the internal resistance change information may include, for example, the maximum change rate of the current AC internal resistance within the most recent preset time length; based on the internal resistance change information, determining whether the current AC internal resistance is currently in a stable state, for example, if the maximum change rate of the current AC internal resistance within the most recent preset time length is less than the preset change rate, determining that the current AC internal resistance is currently in a stable state, and for another example, if the maximum change rate of the current AC internal resistance within the most recent preset time length is greater than or equal to the preset change rate, determining that the current AC internal resistance is not currently in a stable state.

[0063] 102. Based on a preset correlation relationship, determine the internal temperature of the battery associated with the current AC internal resistance.

[0064] In an embodiment of the present application, the preset association relationship represents the association relationship between multiple preset AC internal resistances ACIR and multiple preset battery internal temperatures T, f(T)=ACIR, wherein each preset battery internal temperature is associated with a preset AC internal resistance. Figure 2 As shown, Figure 2The middle curve is the correlation between multiple preset AC internal resistances and multiple preset battery internal temperatures. It can be seen that as the preset battery internal temperature increases, the preset AC internal resistance decreases monotonically, wherein the horizontal axis is the preset battery internal temperature in degrees Celsius (°C), and the vertical axis is the preset AC internal resistance in milliohms (mΩ). In the step of determining the battery internal temperature associated with the current AC internal resistance based on the preset correlation, for example, a preset AC internal resistance equal to the current AC internal resistance can be determined, and then the preset battery internal temperature associated with the preset AC internal resistance is used as the battery internal temperature associated with the current AC internal resistance.

[0065] In some embodiments of the present application, an example of a method for generating a preset association relationship is provided. Specifically, before obtaining the current AC internal resistance of the target battery, it may also include: placing the preset battery in an environment with a preset test temperature, for example, the preset battery may be placed in an environment with a preset test temperature (such as a temperature box) for a preset time, so that the internal battery temperature of the preset battery is equal to the preset test temperature, wherein the value range of the preset test temperature may be, for example, [-40°C, 60°C], the value range of the preset time may be, for example, [5h, 24h], the value range of the charge state of the preset battery may be, for example, [0%, 100%], and the preset battery may be, for example, 1 ampere-hour (Ah)- Lithium iron phosphate (LFP, LiFePO4) soft pack battery; obtain the AC internal resistance of the preset battery in the environment of the preset test temperature, and use it as a preset AC internal resistance, and use the preset test temperature at this time as a preset battery internal temperature, and associate them to obtain a correlation relationship between a preset AC internal resistance and a preset battery internal temperature; take different values ​​of the preset test temperature in turn to obtain the correlation relationship between multiple preset AC internal resistances and multiple preset battery internal temperatures; based on the correlation relationship between multiple preset AC internal resistances and multiple preset battery internal temperatures, generate a preset correlation relationship. The preset correlation relationship can, for example, directly include the correlation relationship between multiple preset AC internal resistances and multiple preset battery internal temperatures.

[0066] 103. The battery internal temperature associated with the current AC internal resistance is used as the current battery internal temperature of the target battery.

[0067] In the embodiment of the present application, since the current AC impedance of the target battery is highly sensitive to the current internal battery temperature of the target battery, the target battery itself can be used as a temperature sensing device to test the current internal battery temperature of the target battery. This test method has high accuracy in obtaining the current internal battery temperature, is simple to operate, and has high test efficiency, and can be used to continuously monitor the current internal battery temperature of the target battery in a working state in real time.

[0068] Among them, the reason why alternating current is used to test the resistance of the target battery is to eliminate the influence of the polarization of the target battery and directly measure the resistance of the properties of the material itself in the target battery to the current. When using alternating current to obtain the current AC internal resistance of the target battery, if the frequency f of the alternating current is large enough, the period T of the alternating current will be smaller, where T = 1 / f. When the period of the alternating current is small enough, the lithium ions and other substances in the target battery do not have time to move a long distance, but just move back and forth in the original position. Therefore, when the frequency f of the alternating current is large enough, it can be considered that: 1. The charge in the target battery does not move, so there will be no charge accumulation, and the charge distribution will not change, so it is believed that no polarization will occur; 2. Since the charge distribution does not change, the capacitance of the target battery will not change; 3. The position of lithium ions and other substances in the target battery has not changed, so there will be no diffusion behavior, so there is no diffusion impedance in the target battery. In summary, when testing the current AC internal resistance of the target battery, an AC power with a frequency of 1000 Hz can be used. It is considered that the current AC internal resistance tested at this time is equal to the ohmic internal resistance of the target battery, that is, the current AC internal resistance is assumed to be equal to the resistance value when the target battery is a resistor.

[0069] In the technical solution disclosed in this embodiment, the battery internal temperature associated with the current AC internal resistance of the target battery is determined based on the correlation between the AC internal resistance and the internal temperature of the battery, and used as the current internal temperature of the battery of the target battery. Compared with the solution of pre-embedded temperature sensors inside the battery, the cost of testing the internal temperature of the battery is lower. Compared with the solution of using the temperature of the battery surface to infer or approximately replace the internal temperature of the battery cell, since the target battery itself can be used as a temperature sensing device, the current AC impedance of the target battery is more sensitive to the current internal temperature of the battery, so the test accuracy of the internal temperature of the battery will also be higher. In addition, the above-mentioned AC internal resistance tester can also be integrated into a battery test cabinet to continuously test the current AC internal resistance and its changes during the charge and discharge process of the target battery, and then calculate the actual current internal temperature of the battery in real time.

[0070] In another embodiment, since the current AC internal resistance of different individual batteries may vary greatly, in order to eliminate the influence of such individual differences, as shown in FIG. Figure 3 As shown, in Figure 1 to Figure 2 Based on any of the embodiments shown in , step 102 may include:

[0071] 301. Obtain a current internal resistance change rate of a current AC internal resistance relative to a first preset standard AC internal resistance.

[0072] In an embodiment of the present application, the current internal resistance change rate of the current AC internal resistance relative to the first preset standard AC internal resistance refers to the deviation value of the current AC internal resistance relative to the first preset standard AC internal resistance. For example, the difference between the current AC internal resistance and the first preset standard AC internal resistance can be determined, and then the ratio of the difference to the first preset standard AC internal resistance can be determined and used as the current internal resistance change rate.

[0073] In some embodiments of the present application, an example is given for determining the first preset standard AC internal resistance. Specifically, before obtaining the current internal resistance change rate of the current AC internal resistance relative to the first preset standard AC internal resistance, it may also include: placing the target battery in an environment with a preset standard temperature, for example, the target battery may be placed in an environment with a preset standard temperature (such as a temperature box) for a preset time so that the internal battery temperature of the target battery is equal to the preset standard temperature, wherein the preset standard temperature may be 25°C, for example; obtaining the AC internal resistance of the target battery in an environment with a preset standard temperature, and using it as the first preset standard AC internal resistance. It can be seen that the embodiment of the present application uses the AC internal resistance of the target battery when the internal battery temperature is the preset standard temperature as the reference value of the AC internal resistance of the target battery.

[0074] 302. Based on a preset correlation relationship, determine the internal temperature of the battery associated with the current internal resistance change rate.

[0075] In the embodiment of the present application, since the preset association relationship represents the association relationship between multiple preset AC internal resistances and multiple preset battery internal temperatures, and each preset internal resistance change rate is determined based on a preset AC internal resistance, the preset association relationship can also represent multiple preset internal resistance change rates ΔACIR / ACIR 25 The correlation relationship between the preset battery internal temperature T and the temperature T is f(T) = ΔACIR / ACIR 25 .For example Figure 4 As shown, Figure 4 The middle curve is the correlation between multiple preset internal resistance change rates and multiple preset battery internal temperatures, wherein the horizontal axis is the preset battery internal temperature in degrees Celsius (°C), and the vertical axis is the preset internal resistance change rate. In the step of determining the battery internal temperature associated with the current internal resistance change rate based on the preset correlation, for example, a preset internal resistance change rate equal to the current internal resistance change rate can be determined, and then the preset battery internal temperature associated with the preset internal resistance change rate is used as the battery internal temperature associated with the current internal resistance change rate.

[0076] In some embodiments of the present application, an example of a method for generating a preset association relationship is provided. Specifically, based on the association relationship between multiple preset AC internal resistances and multiple preset battery internal temperatures, generating the preset association relationship may include: obtaining the internal resistance change rate of each preset AC internal resistance relative to the second preset standard AC internal resistance, and using it as a preset internal resistance change rate ΔACIR / ACIR 25 , where ΔACIR is the difference between the preset AC internal resistance and the second preset standard AC internal resistance, ACIR 25 For the second preset standard AC internal resistance, the preset internal resistance change rate is associated with the preset battery internal temperature associated with the preset AC internal resistance to obtain a correlation relationship between a preset internal resistance change rate and a preset battery internal temperature; after obtaining the correlation relationships between multiple preset internal resistance change rates and multiple preset battery internal temperatures, a preset correlation relationship can be generated based on the correlation relationships between the multiple preset internal resistance change rates and the multiple preset battery internal temperatures. The preset correlation relationship may include, for example, correlation relationships between multiple preset internal resistance change rates and multiple preset battery internal temperatures.

[0077] Among them, an example is given to illustrate the method for determining the second preset standard AC internal resistance. Specifically, similar to the method for determining the first preset standard AC internal resistance, before obtaining the internal resistance change rate of each preset AC internal resistance relative to the second preset standard AC internal resistance, it may also include: placing the preset battery in an environment of a preset standard temperature, for example, the preset battery may be placed in an environment of a preset standard temperature (such as a temperature box) for a preset time so that the internal battery temperature of the preset battery is equal to the preset standard temperature; obtaining the AC internal resistance of the preset battery in an environment of a preset standard temperature, and using it as the second preset standard AC internal resistance. It can be seen that the embodiment of the present application uses the AC internal resistance of the preset battery when the internal battery temperature is the preset standard temperature as the reference value of the AC internal resistance of the preset battery.

[0078] In the technical solution disclosed in this embodiment, by obtaining the current internal resistance change rate of the current AC internal resistance relative to the first preset standard AC internal resistance, and then determining the internal temperature of the battery associated with the current internal resistance change rate based on a preset correlation relationship, the influence of the difference between the current AC internal resistances of different battery individuals on the current internal temperature of the battery is avoided, so that the current internal temperature of the battery of the tested target battery is more accurate.

[0079] In yet another embodiment, in order to ensure the credibility of the current internal battery temperature of the tested target battery, the influence of the state of charge (SOC) on the current AC internal resistance of the target battery may also be detected. Figure 5 As shown, in Figures 1 to 4 Based on any of the embodiments, the method for testing the internal temperature of the battery may further include:

[0080] 501. Place the preset battery in an environment with a preset standard temperature.

[0081] In an embodiment of the present application, placing the preset battery in an environment of a preset standard temperature may include, for example, placing the preset battery in an environment of a preset standard temperature (e.g., a temperature box) for a preset period of time so that the internal battery temperature of the preset battery is equal to the preset standard temperature. The preset standard temperature may be, for example, 25°C.

[0082] 502. Obtain a historical state of charge and a historical AC internal resistance of a preset battery in an environment of a preset standard temperature, and obtain a correlation between the historical state of charge and the historical AC internal resistance.

[0083] In the embodiment of the present application, the historical state of charge and historical AC internal resistance of the preset battery in the environment of the preset standard temperature can be obtained by testing with corresponding instruments. The historical state of charge and historical AC internal resistance of the preset battery in the environment of the same preset standard temperature are associated to obtain an association relationship between the historical state of charge and the historical AC internal resistance.

[0084] 503. Based on the correlation between the historical state of charge and the historical AC internal resistance, determine the influence of the historical state of charge on the historical AC internal resistance.

[0085] In the embodiment of the present application, after obtaining the correlation between a historical state of charge and a historical AC internal resistance, the correlation between multiple historical states of charge and multiple historical AC internal resistances can be obtained by changing the historical state of charge of the preset battery. Figure 6 As shown, Figure 6 The broken line in is the correlation between multiple historical states of charge and multiple historical AC internal resistances. It can be seen that the historical state of charge has little effect on the historical AC internal resistance, where the horizontal axis is the historical state of charge and the vertical axis is the historical AC internal resistance, in milliohms (mΩ). Based on the correlation between multiple historical states of charge and multiple historical AC internal resistances, the influence of the historical state of charge on the historical AC internal resistance can be determined. For example, the maximum change amplitude of the historical AC internal resistance under different historical states of charge can be calculated, and the maximum change amplitude is used as the influence of the historical state of charge on the historical AC internal resistance.

[0086] 504. If the impact degree meets the preset low impact condition, execute the step of obtaining the current AC internal resistance of the target battery.

[0087] In the embodiment of the present application, the preset low impact condition may include, for example, that the impact is less than a preset impact threshold, that is, when the impact is less than the preset impact threshold, step 101 and subsequent steps are performed to obtain a more reliable current battery internal temperature. According to actual research, the impact of the historical state of charge on the historical AC internal resistance usually meets the preset low impact condition, that is, different values ​​of the current state of charge of the target battery usually have little impact on the final determined current battery internal temperature.

[0088] In some embodiments of the present application, in order to further improve the accuracy of the current battery internal temperature obtained by the test, based on the preset association relationship, determining the battery internal temperature associated with the current AC internal resistance may include: obtaining the current state of charge of the target battery; correcting the current AC internal resistance based on the current state of charge to consider the impact of the current state of charge on the current AC internal resistance; based on the preset association relationship, determining the corrected battery internal temperature associated with the current AC internal resistance, and using it as the battery internal temperature associated with the current AC internal resistance. Among them, the detailed steps of determining the corrected battery internal temperature associated with the current AC internal resistance based on the preset association relationship can refer to Figure 1 and / or Figure 3 The detailed steps of determining the internal temperature of the battery associated with the current AC internal resistance based on the preset association relationship are not described here.

[0089] In some embodiments of the present application, the step of correcting the current AC internal resistance based on the current state of charge can be implemented using a correction model of the impact of the historical state of charge on the historical AC internal resistance. Specifically, correcting the current AC internal resistance based on the current state of charge can include: inputting the current state of charge into the correction model; receiving the corrected current AC internal resistance output by the correction model, thereby correcting the current AC internal resistance. The correction model can be generated based on the correlation between the historical state of charge and the historical AC internal resistance, and the correction model can be, for example, any machine learning model, which is not limited here.

[0090] In some embodiments of the present application, the step of correcting the current AC internal resistance based on the current state of charge can be performed when the above-mentioned influence does not meet the preset low influence condition, so as to improve the accuracy of the current internal temperature of the battery tested to a greater extent. Of course, the step of correcting the current AC internal resistance based on the current state of charge can also be performed when the above-mentioned influence meets or does not meet the preset low influence condition, which is not limited here.

[0091] Based on any of the above embodiments, an example of an application scenario of the battery internal temperature test method is given. The application scenario may include:

[0092] Application scenario 1: The problem of battery discharge at high and low temperatures.

[0093] Specifically, when it is necessary to test the working condition of the battery at different internal battery temperatures, due to the lack of an effective battery internal temperature test solution, the battery is generally left at a corresponding ambient temperature for a sufficiently long time (generally 5 to 24 hours) and then the corresponding working condition test is performed. After adopting the battery internal temperature test method in the embodiment of the present application, the battery internal temperature can be monitored in real time, and the corresponding working condition test can be started when the battery internal temperature is stable, so as to save time and cost.

[0094] Application scenario 2: battery safety field.

[0095] Specifically, when a battery safety accident occurs, the internal temperature of the battery generally rises first. Compared with the solution of adding a temperature sensor on the battery surface to test the battery surface temperature for temperature warning, the method for testing the internal temperature of the battery in the embodiment of the present application can detect the actual temperature rise of the battery earlier, take countermeasures earlier, and prevent the occurrence of battery safety accidents.

[0096] In order to better implement the battery internal temperature testing method in the embodiment of the present application, on the basis of the battery internal temperature testing method, the present application also provides a battery internal temperature testing device, such as Figure 7 As shown, the battery internal temperature testing device 700 includes an acquisition module 701, a determination module 702 and a processing module 703, which are specifically as follows:

[0097] An acquisition module 701 is used to acquire the current AC internal resistance of the target battery;

[0098] A determination module 702 is used to determine the battery internal temperature associated with the current AC internal resistance based on a preset association relationship, wherein the preset association relationship represents an association relationship between a plurality of preset AC internal resistances and a plurality of preset battery internal temperatures;

[0099] The processing module 703 is used to use the battery internal temperature associated with the current AC internal resistance as the current battery internal temperature of the target battery.

[0100] The present application also provides a computer device that integrates any of the battery internal temperature testing devices provided in the present application. Figure 8 As shown, it shows a schematic diagram of the structure of the computer device involved in the embodiment of the present application, specifically:

[0101] The computer device may include one or more processing core processors 801, one or more computer-readable storage media memories 802, a power supply 803, an input unit 804 and other components. Those skilled in the art will appreciate that Figure 8The computer device structure shown in the figure is not intended to limit the computer device, and may include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently.

[0102] The processor 801 is the control center of the computer device. It uses various interfaces and lines to connect various parts of the entire computer device. By running or executing software programs and / or modules stored in the memory 802 and calling data stored in the memory 802, it executes various functions of the computer device and processes data, thereby monitoring the computer device as a whole. Optionally, the processor 801 may include one or more processing cores; preferably, the processor 801 may integrate an application processor and a modem processor, wherein the application processor mainly processes the operating system, user interface, and application programs, and the modem processor mainly processes wireless communications. It is understandable that the above-mentioned modem processor may not be integrated into the processor 801.

[0103] The memory 802 can be used to store software programs and modules. The processor 801 executes various functional applications and data processing by running the software programs and modules stored in the memory 802. The memory 802 may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc.; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 802 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other volatile solid-state storage devices. Accordingly, the memory 802 may also include a memory controller to provide the processor 801 with access to the memory 802.

[0104] The computer device also includes a power supply 803 for supplying power to each component. Preferably, the power supply 803 can be logically connected to the processor 801 through a power management system, so that the power management system can manage charging, discharging, power consumption and other functions. The power supply 803 can also include one or more DC or AC power supplies, recharging systems, power failure detection circuits, power converters or inverters, power status indicators and other arbitrary components.

[0105] The computer device may further include an input unit 804, which may be used to receive input digital or character information and generate keyboard, mouse, joystick, optical or trackball signal input related to user settings and function control.

[0106] Although not shown, the computer device may further include a display unit, etc., which will not be described in detail herein. Specifically in this embodiment, the processor 801 in the computer device will load the executable files corresponding to the processes of one or more application programs into the memory 802 according to the following instructions, and the processor 801 will run the application programs stored in the memory 802, thereby realizing various functions, such as:

[0107] Obtain the current AC internal resistance of the target battery; determine the battery internal temperature associated with the current AC internal resistance based on a preset association relationship, wherein the preset association relationship represents an association relationship between multiple preset AC internal resistances and multiple preset battery internal temperatures; and use the battery internal temperature associated with the current AC internal resistance as the current battery internal temperature of the target battery.

[0108] A person of ordinary skill in the art will appreciate that all or part of the steps in the various methods of the above embodiments may be completed by instructions, or by controlling related hardware through instructions. The instructions may be stored in a computer-readable storage medium and loaded and executed by a processor.

[0109] To this end, an embodiment of the present application provides a computer-readable storage medium, which may include: a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, etc. A computer program is stored thereon, and the computer program is loaded by a processor to execute the steps in any of the battery internal temperature test methods provided in the embodiments of the present application. For example, the computer program may be loaded by a processor to execute the following steps:

[0110] Obtain the current AC internal resistance of the target battery; determine the battery internal temperature associated with the current AC internal resistance based on a preset association relationship, wherein the preset association relationship represents an association relationship between multiple preset AC internal resistances and multiple preset battery internal temperatures; and use the battery internal temperature associated with the current AC internal resistance as the current battery internal temperature of the target battery.

[0111] In addition, an embodiment of the present application provides a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. A processor of an electronic device reads the computer instruction from the computer-readable storage medium and executes the computer instruction, so that the electronic device executes to implement the battery internal temperature test method as described in any one of the above.

[0112] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the detailed description of other embodiments above, and will not be repeated here.

[0113] The specific implementation of the above operations can be found in the previous embodiments, which will not be described in detail here.

[0114] The above is a detailed introduction to a battery internal temperature testing method, device and medium provided in the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technicians in this field, according to the ideas of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A method for testing the internal temperature of a battery, characterized in that: The method for testing the internal temperature of the battery includes: Get the current AC internal resistance of the target battery; Based on a preset correlation relationship, determining the battery internal temperature associated with the current AC internal resistance, wherein the preset correlation relationship represents a correlation relationship between a plurality of preset AC internal resistances and a plurality of preset battery internal temperatures; The battery internal temperature associated with the current AC internal resistance is used as the current battery internal temperature of the target battery.

2. The method for testing the internal temperature of a battery as claimed in claim 1, characterized in that: The determining, based on the preset association relationship, the internal temperature of the battery associated with the current AC internal resistance includes: Acquire a current internal resistance change rate of the current AC internal resistance relative to a first preset standard AC internal resistance; Based on the preset association relationship, the battery internal temperature associated with the current internal resistance change rate is determined, wherein the preset association relationship represents the association between multiple preset internal resistance change rates and multiple preset battery internal temperatures, and each preset internal resistance change rate is determined based on one preset AC internal resistance.

3. The method for testing the internal temperature of a battery as claimed in claim 2, characterized in that: Before obtaining the current internal resistance change rate of the current AC internal resistance relative to the first preset standard AC internal resistance, the method may further include: Placing the target battery in an environment with a preset standard temperature; The AC internal resistance of the target battery in the environment of the preset standard temperature is obtained and used as the first preset standard AC internal resistance.

4. The method for testing the internal temperature of a battery as claimed in claim 1, characterized in that: Before obtaining the current AC internal resistance of the target battery, the method may further include: Place the preset battery in an environment with a preset test temperature; Acquire the AC internal resistance of the preset battery in the environment of the preset test temperature and use it as the preset AC internal resistance, and use the preset test temperature as the preset battery internal temperature to obtain a correlation relationship between the preset AC internal resistance and the preset battery internal temperature; The preset association relationship is generated based on the association relationship between the plurality of preset AC internal resistances and the plurality of preset battery internal temperatures.

5. The method for testing the internal temperature of a battery as claimed in claim 4, characterized in that: The generating the preset association relationship based on the association relationship between the plurality of preset AC internal resistances and the plurality of preset battery internal temperatures comprises: Obtaining an internal resistance change rate of each of the preset AC internal resistances relative to a second preset standard AC internal resistance as a preset internal resistance change rate, and obtaining a correlation relationship between the preset internal resistance change rate and a preset battery internal temperature; The preset correlation relationship is generated based on the correlation relationship between the plurality of preset internal resistance change rates and the plurality of preset battery internal temperatures.

6. The method for testing the internal temperature of a battery as claimed in claim 1, characterized in that: The method for testing the internal temperature of the battery also includes: Place the preset battery in an environment with a preset standard temperature; Acquire a historical state of charge and a historical AC internal resistance of the preset battery in an environment of the preset standard temperature, and obtain a correlation relationship between the historical state of charge and the historical AC internal resistance; Determining the influence of the historical state of charge on the historical AC internal resistance based on the correlation between the historical state of charge and the historical AC internal resistance; If the impact degree meets the preset low impact condition, the step of obtaining the current AC internal resistance of the target battery is performed.

7. The method for testing the internal temperature of a battery as claimed in claim 1, characterized in that: The determining, based on the preset association relationship, the internal temperature of the battery associated with the current AC internal resistance includes: Obtaining a current state of charge of the target battery; Correcting the current AC internal resistance based on the current state of charge; Based on the preset association relationship, a corrected battery internal temperature associated with the current AC internal resistance is determined and used as the battery internal temperature associated with the current AC internal resistance.

8. The method for testing the internal temperature of a battery according to any one of claims 1 to 7, characterized in that: After obtaining the current AC internal resistance of the target battery, the method may further include: Determining a current state of the current AC internal resistance; If the current AC internal resistance is currently in a stable state, the step of determining the internal temperature of the battery associated with the current AC internal resistance based on the preset association relationship is performed.

9. A computer device, characterized in that: The computer device comprises: one or more processors; Memory; and One or more application programs, wherein the one or more application programs are stored in the memory and are configured to be executed by the processor to implement the steps in the method for testing the internal temperature of a battery according to any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and the computer program is loaded by a processor to execute the steps in the method for testing the internal temperature of a battery according to any one of claims 1 to 8.

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