A method for determining battery thermal physical property parameters and related device and storage medium

Abstract

The present application discloses a method for determining the thermal physical property parameters of a battery and a related device and storage medium. The method comprises: performing a constant temperature charge and discharge test on a target battery, and obtaining the static temperature change data and the operating voltage data of the target battery; fitting the convective heat transfer coefficient using the static temperature change data of the target battery, and substituting it into the coupling model of the target battery; performing a heating simulation on the coupling model of the target battery according to the heat generation rate curve, so as to calculate the simulated temperature curve and the simulated voltage curve through the model; judging whether the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than the corresponding preset errors; if they are not both less than the preset errors, adjusting the values ​​of the target parameters in the model, and returning to perform a heating simulation on the model; wherein the target parameters include at least the thermal physical property parameters of the target battery; if they are both less than the preset errors, outputting the values ​​of the various thermal physical property parameters in the model.

Description

Technical Field

[0001] The present application relates to the technical field of battery parameter analysis, and in particular to a method for determining battery thermal physical property parameters and related devices and storage media. Background Art

[0002] Lithium-ion batteries are energy storage devices that convert chemical energy into electrical energy based on electrochemical principles. They are widely used in power batteries and large-scale energy storage applications due to their high energy density, no memory effect, and rechargeability. However, the temperature sensitivity of lithium batteries seriously affects their performance and safety characteristics. Therefore, it is usually necessary to obtain the thermophysical parameters of the battery, develop a thermal management system based on the thermophysical parameters of the battery, and formulate appropriate thermal management strategies to manage the battery.

[0003] The current method of obtaining the thermophysical parameters of lithium-ion batteries is mainly to place the battery in an adiabatic environment, for example, to place the battery in an accelerating calorimeter under adiabatic conditions, so as to avoid heat interaction with the outside world and determine the applied heat. The battery is then heated by a heating device placed outside the battery, so that the temperature rise rate of the battery and the thermophysical parameters are connected, and then the temperature rise is analyzed based on the law of heat conservation to obtain the thermophysical parameters of the battery.

[0004] However, an adiabatic environment is a relatively harsh environment, so the difficulty and cost of creating an adiabatic environment space are relatively high, especially for a relatively large adiabatic environment space, which also makes this method less adaptable to battery size. In addition, heating the battery through an external heating device, such as a heating sheet, not only increases the cost, but also requires different devices to be set up for different batteries in order to effectively heat, making the whole process cumbersome. Summary of the invention

[0005] Based on the above-mentioned deficiencies of the prior art, the present application provides a method for determining battery thermal physical property parameters and related devices and storage media to solve the problems of poor adaptability and cumbersomeness of thermal physical property parameter testing in the prior art.

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] The first aspect of the present application provides a method for determining thermal physical property parameters of a battery, comprising:

[0008] Perform a constant temperature charge and discharge test on the target battery under a preset test condition, and obtain the static temperature change data and working voltage data of the target battery; wherein the constant temperature charge and discharge test is to charge or discharge in a constant temperature environment and to cool down statically; the static temperature change data is the data of the temperature of the battery during the static cooling process; the working voltage data is the data of the voltage of the battery during the charging or discharging process;

[0009] Using the static temperature change data of the target battery, fitting the convective heat transfer coefficient of the target battery;

[0010] Substituting the convection heat transfer coefficient of the target battery into the coupling model of the target battery; wherein the coupling model of the target battery is a coupling model of an electrochemical model and a heat transfer model;

[0011] According to the heat generation rate curve of the test condition, a heating simulation is performed on the coupling model of the target battery, so as to calculate a simulated temperature curve and a simulated voltage curve through the coupling model of the target battery; wherein the heat generation rate curve of the test condition is calculated based on the operating voltage data;

[0012] Determine whether the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than corresponding preset errors; wherein the actual temperature curve and the actual voltage curve are curves of temperature and voltage of the target battery during the charging and discharging process;

[0013] If it is determined that the error between the simulated temperature curve and the actual temperature curve or the error between the simulated voltage curve and the actual voltage curve is not less than the corresponding preset error, the value of the target parameter in the coupling model of the target battery is adjusted, and the heat generation rate curve according to the target working condition is returned to perform heating simulation on the coupling model of the target battery; wherein the target parameter includes at least various thermophysical property parameters of the target battery;

[0014] If it is determined that the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both smaller than the corresponding preset errors, the values ​​of the various thermophysical property parameters in the coupling model of the current target battery are output.

[0015] Optionally, in the above-mentioned method for determining the battery thermophysical property parameters, the constant temperature charge and discharge test of the target battery under the preset test conditions includes:

[0016] For each of the preset test conditions, the target battery is charged or discharged at a constant ambient temperature and according to a preset rate corresponding to the test condition, and then the target battery is left to cool at a constant set ambient temperature corresponding to the test condition until the temperature of the target battery drops to the set ambient temperature corresponding to the test condition; wherein the preset test conditions include test conditions with a large rate and test conditions with a small rate.

[0017] Optionally, in the above-mentioned method for determining the battery thermophysical property parameters, the step of fitting the convective heat transfer coefficient of the target battery using the static temperature change data of the target battery includes:

[0018] According to the target temperature function, the static temperature change data of the target battery are used to obtain various parameters of the target temperature function; wherein the target temperature function is a result that the battery temperature is equal to the ambient temperature plus the product of a constant parameter and a target exponential term; the target exponential term is an exponential term with the product of the negative of the heat transfer parameter and time as the base; the heat transfer parameter is equal to the product of the convection heat transfer coefficient and the heat transfer area, divided by the product of the mass of the battery and the specific heat capacity;

[0019] The convective heat transfer coefficient of the target battery is calculated according to the heat transfer parameters.

[0020] Optionally, in the above-mentioned method for determining the thermal physical property parameters of a battery, the method further includes:

[0021] Constructing a coupling model of the target battery based on the cell design parameters, thermodynamic parameters and kinetic parameters of the target battery;

[0022] Based on the cell design parameters of the target battery, the initial thermophysical parameters of the target battery are calculated and substituted into the coupling model of the target battery.

[0023] Optionally, in the above-mentioned method for determining the battery thermophysical property parameters, adjusting the value of the target parameter in the coupling model of the target battery includes:

[0024] If the error between the simulated voltage curve and the actual voltage curve is not less than the corresponding preset error, adjusting the values ​​of the thermodynamic parameters and the kinetic parameters of the battery cells in the coupling model of the target battery;

[0025] If the error between the simulated temperature curve and the actual temperature curve is not less than the corresponding preset error, each of the thermophysical property parameters in the coupling model of the target battery is adjusted.

[0026] Optionally, in the above-mentioned method for determining the battery thermophysical property parameters, the determining whether the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than corresponding preset errors, includes:

[0027] First, the error between the simulated voltage curve and the actual voltage curve is determined. If the error between the simulated voltage curve and the actual voltage curve is less than the corresponding preset error, then the error between the simulated temperature curve and the actual temperature curve is determined.

[0028] The second aspect of the present application provides a battery thermal physical property parameter determination device, comprising:

[0029] A test unit, used to perform a constant temperature charge and discharge test on a target battery under a preset test condition, and obtain static temperature change data and operating voltage data of the target battery; wherein the constant temperature charge and discharge test is to charge or discharge in a constant temperature environment and to cool statically; the static temperature change data is the data of the temperature of the battery during the static cooling process; the operating voltage data is the data of the voltage of the battery during the charging or discharging process;

[0030] A heat transfer coefficient fitting unit, used to fit the convective heat transfer coefficient of the target battery using the static temperature change data of the target battery;

[0031] A substitution unit, used for substituting the convection heat transfer coefficient of the target battery into the coupling model of the target battery; wherein the coupling model of the target battery is a coupling model of an electrochemical model and a heat transfer model;

[0032] A simulation unit, configured to perform heating simulation on the coupling model of the target battery according to the heat generation rate curve of the test condition, so as to calculate a simulated temperature curve and a simulated voltage curve through the coupling model of the target battery; wherein the heat generation rate curve of the test condition is calculated based on the operating voltage data;

[0033] An error judgment unit, used to judge whether the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than corresponding preset errors; wherein the actual temperature curve and the actual voltage curve are curves of temperature and voltage of the target battery during the charging and discharging process;

[0034] an adjustment unit, configured to adjust the value of the target parameter in the coupling model of the target battery and return the result to the simulation unit when it is determined that the error between the simulated temperature curve and the actual temperature curve or the error between the simulated voltage curve and the actual voltage curve is not less than the corresponding preset error;

[0035] The output unit is used to output the values ​​of each of the thermophysical property parameters in the coupling model of the current target battery when it is determined that the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than the corresponding preset errors.

[0036] Optionally, in the above-mentioned battery thermal physical property parameter determination device, the testing unit includes:

[0037] The test subunit is used for charging or discharging the target battery at a constant ambient temperature and at a preset rate corresponding to the test condition for each of the preset test conditions, and then cooling the target battery at a constant set ambient temperature corresponding to the test condition until the temperature of the target battery drops to the set ambient temperature corresponding to the test condition; wherein the preset test conditions include test conditions with a large rate and test conditions with a small rate.

[0038] Optionally, in the above-mentioned battery thermophysical property parameter determination device, the heat transfer coefficient fitting unit includes:

[0039] A parameter fitting unit, for obtaining various parameters of the target temperature function according to the static temperature change data of the target battery; wherein the target temperature function is a result of the battery temperature being equal to the ambient temperature plus the product of a constant parameter and a target exponential term; the target exponential term is an exponential term with the product of the negative of a heat transfer parameter and time as the base; the heat transfer parameter is equal to the product of a convection heat transfer coefficient and a heat transfer area, divided by the product of a mass of the battery and a specific heat capacity;

[0040] A parameter calculation unit is used to calculate the convective heat transfer coefficient of the target battery according to the heat transfer parameter.

[0041] Optionally, in the above-mentioned battery thermal physical property parameter determination device, it also includes:

[0042] A model building unit, used to build a coupling model of the target battery based on the cell design parameters, thermodynamic parameters and kinetic parameters of the target battery;

[0043] An initialization unit is used to calculate the initial thermophysical parameters of the target battery based on the cell design parameters of the target battery, and substitute the initial thermophysical parameters into the coupling model of the target battery.

[0044] Optionally, in the above-mentioned battery thermophysical property parameter determination device, the adjustment unit includes:

[0045] a first adjustment unit, configured to adjust the values ​​of the thermodynamic parameters and the kinetic parameters of the battery cells in the coupling model of the target battery when the error between the simulated voltage curve and the actual voltage curve is not less than the corresponding preset error;

[0046] The second adjustment unit is used to adjust each of the thermophysical property parameters in the coupling model of the target battery when the error between the simulated temperature curve and the actual temperature curve is not less than the corresponding preset error.

[0047] Optionally, in the above-mentioned battery thermophysical property parameter determination device, the error judgment unit includes:

[0048] The error judgment subunit is used to first judge the error between the simulated voltage curve and the actual voltage curve, and then judge the error between the simulated temperature curve and the actual temperature curve if the error between the simulated voltage curve and the actual voltage curve is less than the corresponding preset error.

[0049] A third aspect of the present application provides an electronic device, including:

[0050] Memory and processor;

[0051] Wherein, the memory is used to store programs;

[0052] The processor is used to execute the program, and when the program is executed, it is specifically used to implement the battery thermal property parameter determination method as described in any one of the above.

[0053] In a fourth aspect, the present application provides a computer storage medium for storing a computer program. When the computer program is executed, it is used to implement the battery thermal property parameter determination method as described in any one of the above.

[0054] The present application provides a method for determining the thermal physical property parameters of a battery, which performs a constant temperature charge and discharge test on a target battery under a preset test condition, and obtains the static temperature change data and the operating voltage data of the target battery. Among them, the constant temperature charge and discharge test is to charge or discharge in a constant temperature environment, and to cool statically, so the battery is heated by charging and discharging the battery, and no additional heating device is required for heating. All batteries are used, making the whole process simpler. The static temperature change data is the data of the temperature of the battery during the static cooling process, so that the convective heat transfer coefficient can be analyzed based on this. The operating voltage data is the data of the voltage of the battery during the charging or discharging process, so as to simulate the heating of the model based on this. Then, the static temperature change data of the target battery is used to fit the convective heat transfer coefficient of the target battery, and the convective heat transfer coefficient of the target battery is substituted into the coupling model of the target battery. Among them, the coupling model of the target battery is a coupling model of the electrochemical model and the heat transfer model, so that the heat lost by convective heat transfer during static cooling in a constant temperature environment is taken into account, ensuring that the thermal physical parameters of the battery can be accurately analyzed under constant temperature conditions, and static cooling in a constant temperature environment is relatively easy to achieve, so a larger constant temperature environment can be achieved at a low cost, which not only effectively reduces the cost, but also can adapt to various battery sizes. Then, according to the heat generation rate curve of the test condition, the coupling model of the target battery is heated and simulated to calculate the simulated temperature curve and the simulated voltage curve through the coupling model of the target battery. Among them, the heat generation rate curve of the test condition is calculated based on the working voltage data. Then, it is determined whether the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than the corresponding preset error. Among them, the actual temperature curve and the actual voltage curve are the temperature and voltage curves of the target battery during the charging and discharging process. If it is determined that one of the items is not less than the corresponding preset error, the value of the target parameter in the coupling model of the target battery is adjusted, and the execution is returned to perform heating simulation on the coupling model of the target battery according to the heat generation rate curve of the target condition. The target parameters at least include the various thermophysical parameters of the target battery. If both items are less than the corresponding preset errors, the values ​​of the various thermophysical parameters in the coupling model of the current target battery are output, thereby realizing a simpler and more applicable method for obtaining the thermophysical parameters of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0056] Figure 1A flow chart of a method for determining thermal physical property parameters of a battery provided in an embodiment of the present application;

[0057] Figure 2 A schematic diagram of an example of a fitting static temperature curve provided in an embodiment of the present application;

[0058] Figure 3 A schematic diagram of an example of a voltage curve for discharge at 0.33C provided in an embodiment of the present application;

[0059] Figure 4 A schematic diagram of an example of a voltage curve for discharge at 1C provided in an embodiment of the present application;

[0060] Figure 5 A schematic diagram of an example of a voltage curve for discharge at 3C provided in an embodiment of the present application;

[0061] Figure 6 A schematic diagram of an example of a simulated temperature curve and an actual temperature curve provided in an embodiment of the present application;

[0062] Figure 7 A schematic diagram of the architecture of a device for determining thermal physical property parameters of a battery provided in an embodiment of the present application;

[0063] Figure 8 A schematic diagram of the architecture of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0064] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0065] In this application, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0066] The present application embodiment provides a method for determining battery thermal physical property parameters, such as Figure 1 As shown, the following steps are included:

[0067] S101. Perform a constant temperature charge and discharge test on a target battery under a preset test condition, and obtain static temperature change data and operating voltage data of the target battery.

[0068] Among them, the constant temperature charge and discharge test is to charge or discharge in a constant temperature environment and let it cool down. The static temperature change data is the curve of the battery temperature during the static cooling process. The working voltage data is the curve of the battery voltage during the charging or discharging process.

[0069] It should be noted that the battery will generate heat during the charging and discharging process, thereby increasing the temperature of the battery. Therefore, in the embodiment of the present application, the battery is heated directly by charging or discharging, and no external equipment is required to heat the battery, nor is it necessary to place it in an insulating environment for testing, thereby effectively reducing costs and making the acquisition process of thermal physical parameters simpler. Optionally, since multiple tests are required, the battery is usually charged, and the next time it can be discharged. At this time, the battery power will decrease again, so it can be charged again next time, and so on. The cycle is repeated to obtain multiple preset test conditions and static temperature change data and working voltage data. Optionally, the charging process can specifically be charging from zero power to a fully charged state, and the corresponding discharging process is to discharge the power from a fully charged state to zero power.

[0070] Since the heat generated by the battery itself during the charging and discharging process heats the battery, the heat generated can be determined by the battery voltage. Therefore, it is necessary to collect the working voltage data of the battery during the charging and discharging process to simulate the heating of the battery. The working voltage data can specifically be a working voltage curve, that is, a curve of the relationship between voltage and time during the charging and discharging process.

[0071] Moreover, in an embodiment of the present application, the charging and discharging process of the battery, that is, the heating process of the battery, is carried out in a constant temperature environment. For example, the battery can be placed in an oven environment, and the internal temperature is kept at a constant value, such as 25 degrees Celsius, by the oven. However, the battery will have convective heat transfer, so the heat of convective heat transfer also needs to be considered. Therefore, in an embodiment of the present application, after the battery is charged or discharged, the ambient temperature during the static cooling process is constant, that is, it is statically cooled in a set constant temperature environment, that is, no other intervention is required to reduce the number of variables. At this time, the battery does not generate heat, and the battery temperature change is entirely due to the natural convection heat dissipation of the environment. Optionally, the battery can be left to stand until the temperature is consistent with the temperature of the set constant temperature environment, that is, convective heat transfer no longer occurs.

[0072] Since the static cooling process is a cooling process of pure convective heat transfer of the battery, the data of this process can be collected to analyze the convective heat transfer situation, specifically, the convective heat transfer coefficient. Later, when determining the thermophysical parameters, the heat of convective heat transfer is further considered based on the convective heat transfer coefficient, so that the test can be carried out in a set constant temperature environment, and the thermophysical parameters can also be determined. The constant temperature environment is relatively easy to achieve, even a constant temperature environment in a larger space is easy to achieve, so there is no need for a strict insulation environment, which can effectively reduce costs and can be applied to batteries of various sizes and shapes. At the same time, it can be carried out during other charging and discharging tests, or the test data can be used in battery development electrical performance tests (experiments that must be done for battery development), saving test time and improving test efficiency.

[0073] The data obtained during the static cooling process is static temperature change data. Specifically, it can be a static temperature curve, that is, a curve showing the temperature change over time during the static cooling process, for example, Figure 2 The temperature and time curve during the static cooling process is shown.

[0074] Optionally, in another embodiment of the present application, the preset test conditions need to include multiple ones, that is, the battery is charged and discharged under multiple different conditions and the subsequent steps are performed. Since there are multiple thermophysical parameters that need to be determined, and when charging and discharging are performed under different conditions, the weights that mainly affect different thermophysical parameters are different, so the corresponding thermophysical parameters can also be adjusted accordingly through the data of different test conditions to obtain more accurate thermophysical parameters and improve efficiency. In addition, by analyzing the data of multiple conditions, it is also possible to effectively avoid contingency and effectively improve the accuracy of the results.

[0075] Among them, different test conditions mainly involve different charge and discharge rates and different temperatures of the set constant temperature environment.

[0076] Optionally, in the embodiment of the present application, a specific implementation of step S101 includes:

[0077] For each preset test condition, the target battery is charged or discharged at a preset rate corresponding to the test condition at a constant ambient temperature, and the target battery is left to cool at a set ambient temperature corresponding to the constant test condition until the temperature of the target battery drops to the set ambient temperature corresponding to the test condition.

[0078] Among them, the preset rate refers to the preset charge and discharge rate, such as 0.33C, 1C and 3C. In addition, the preset test conditions include the test conditions of large rate and the test conditions of small rate. The division of large rate and small rate can also be performed when setting the rate. The temperature difference between the inside and outside of the battery is large at a large rate, mainly due to the influence of thermal conductivity, which facilitates fitting an accurate thermal conductivity. When charging and discharging at a small rate, an accurate specific heat capacity can be fitted.

[0079] S102. Using the static temperature change data of the target battery, the convective heat transfer coefficient of the target battery is obtained by fitting.

[0080] It should be noted that during the static cooling process, the battery only conducts convective heat exchange with the environment, so that the temperature of the battery changes continuously over time, and the main influencing factor of convective heat exchange is the convective heat transfer coefficient. Therefore, by analyzing the static temperature change data of the target battery, the convective heat transfer coefficient of the target battery can be fitted. Specifically, a corresponding temperature curve can be drawn based on the static temperature change data, and a function representing the temperature curve can be fitted according to the convective heat transfer formula. Since the temperature curve is related to the convective heat transfer coefficient, the convective heat transfer coefficient will exist in the function of the temperature curve.

[0081] Optionally, in another embodiment of the present application, a specific implementation of step S102 includes:

[0082] According to the target temperature function, the static temperature change data of the target battery is used to obtain various parameters of the target temperature function, and the convective heat transfer coefficient of the target battery is calculated based on the heat transfer parameters.

[0083] Among them, the target temperature function is the result of the battery temperature being equal to the ambient temperature plus the constant parameter multiplied by the target exponential term. The target exponential term is an exponential term with the negative of the heat transfer parameter multiplied by time as the base. The heat transfer parameter is equal to the product of the convection heat transfer coefficient and the heat transfer area, divided by the product of the mass of the battery and the specific heat capacity.

[0084] Specifically, based on Newton's law of cooling, the static cooling process can be expressed as:

[0085]

[0086] Where m represents the mass of the target battery; C p represents the specific heat capacity of the target battery; T represents the temperature of the target battery; t represents time; h represents the convection heat transfer coefficient; A represents the convection heat transfer area; T sur Indicates the ambient temperature, that is, the temperature at which the constant temperature is set.

[0087] In order to facilitate fitting, the above formula can be transformed into:

[0088]

[0089]

[0090] Among them, B is the constant parameter; It is a target index type; is the heat transfer parameter.

[0091] Therefore, the above formula can be fitted to determine the various parameters in the formula. Figure 2 As shown in the figure, the fitting formula is: y=24.94+6.27*exp(-0.0008844*4), and the fitting correlation coefficient R^2=0.9993, so the fitting effect is relatively good, and the heat transfer parameter obtained by fitting can be determined to be 0.0008844. Since mass and area are both known fixed parameters, the convective heat transfer coefficient can be obtained, or more precisely, an expression of the convective heat transfer coefficient about the specific heat capacity. When the specific heat capacity is continuously adjusted later, the corresponding convective heat transfer coefficient can be obtained, that is, the convective heat transfer coefficient is calculated by the following formula:

[0092]

[0093] In the present application, through the above method, the convective heat transfer coefficient can be first obtained through test conditions, and the convective heat transfer coefficient can be decoupled from the heat dissipation parameters of the thermophysical parameters to improve the calculation efficiency. At the same time, it can be input into the subsequent coupling model, and in turn, the simulated temperature data can be used to reversely infer the thermal physical parameters of the battery to achieve accurate determination of the thermal physical parameters.

[0094] S103. Substitute the convective heat transfer coefficient of the target battery into the coupling model of the target battery.

[0095] Among them, the coupling model of the target battery is a coupling model of the electrochemical model and the heat transfer model. This solution is to heat the battery by charging and discharging, that is, to generate heat through the chemical reaction of the battery to change the battery temperature. Since the change in temperature will affect the kinetic parameters of the battery, and the change in the kinetic parameters will also affect the change in temperature. Therefore, in the embodiment of the present application, the electrochemical model and the heat transfer model are coupled to build a model of the heat generation mechanism of the battery. In addition, the convective heat transfer of the battery needs to be taken into account in the heat transfer model, so the convective heat transfer coefficient of the target battery currently obtained needs to be introduced into the coupling model of the target battery, so that the coupling model of the target battery takes into account the convective heat transfer of the current working conditions, thereby improving the accuracy of the coupling model.

[0096] Specifically, the coupling model of the target battery can be constructed using the battery cell design parameters, thermodynamic parameters and kinetic parameters of the target battery. Among them, the battery design parameters may include one or more of the battery pole piece length, battery pole piece width, battery current collector length, battery current collector width, battery current collector thickness, battery current collector position, battery pole piece thickness, battery coating thickness, diaphragm thickness, number of battery pole pieces, battery length, battery width, battery height, and battery thickness. Thermodynamic parameters may include the initial lithium insertion concentration of the positive and negative electrode materials, the gram capacity of the positive and negative electrode materials, the OCV curves of the positive and negative electrodes, etc. The kinetic parameters may include the solid phase diffusion coefficient and activation energy of the positive and negative electrodes, the reaction rate and activation energy of the positive and negative electrodes, the conductivity of the positive and negative electrodes, the tortuosity of the pole pieces and diaphragms, the diffusion coefficient of the electrolyte, the conductivity of the electrolyte, etc.

[0097] S104. Perform heating simulation on the coupling model of the target battery according to the heat generation rate curve of the test condition, so as to calculate a simulated temperature curve and a simulated voltage curve through the coupling model of the target battery.

[0098] It should be noted that since the coupling model of the target battery is a model of the battery heat generation mechanism of the target battery, the temperature of the target battery under the simulated heating condition of the heat generation rate curve can be calculated through this model, so that the simulated temperature curve can be obtained. In this application, the relationship between the convective heat transfer coefficient and the specific heat capacity is constructed through the test conditions and input into the coupling model, so as to calibrate the coupling model and improve the accuracy of the coupling model. At the same time, the number of parameters to be determined can be reduced, the model can be reduced in order, and the efficiency can be improved. Among them, the heat generation rate curve of the test condition is calculated based on the working voltage data. Specifically, it can be calculated according to the following Bernadi equation:

[0099]

[0100] Among them, U ter and U ocv are the terminal voltage of the battery and the open circuit voltage of the battery respectively.

[0101] It should be noted that since the actual data during the test needs to be compared with the simulated data of the model, it is necessary to ensure that both are heated in the same way. Therefore, the working voltage data obtained during the test is required to simulate the heating of the model. Specifically, the working voltage data can be applied to the above-mentioned Bernadi equation, and the equation is applied to the model. Therefore, according to the energy conservation equation in the model, the thermal physical parameters of the target battery can be analyzed;

[0102] Specifically, the energy conservation equation in this process is:

[0103]

[0104] Among them, k x , k y , k z Represents the thermal conductivity in three directions. x The thermal conductivity in the thickness direction of the battery is k y and k z is the thermal conductivity of the battery large surface, and the two are equal.

[0105] It should also be noted that when analyzing the thermal physical parameters of a battery for the first time, the various thermal physical parameters of the target battery have not yet been determined. In this case, an initial value can be assigned to each thermal physical parameter, and then accurate thermal physical parameters can be obtained through subsequent continuous iterative optimization.

[0106] Therefore, optionally, in another embodiment of the present application, it is also necessary to further include:

[0107] Based on the battery cell design parameters, thermodynamic parameters and kinetic parameters of the target battery, a coupling model of the target battery is constructed, and based on the battery cell design parameters of the target battery, the initial thermophysical parameters of the target battery are calculated and substituted into the coupling model of the target battery.

[0108] Among them, the initial values ​​of various thermophysical parameters are calculated theoretically, and the specific calculation process is as follows:

[0109]

[0110]

[0111]

[0112]

[0113] in, is the thickness of single component material; is the total thickness of the battery cell; It is a single-component material heat conduction system; is the density of single component material; is the specific heat capacity of a single component material; is the density of the battery cell.

[0114] S105 , determining whether the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both smaller than corresponding preset errors.

[0115] The actual temperature curve and the actual voltage curve are curves of the temperature and voltage of the target battery during the charging and discharging process.

[0116] Optionally, the simulated temperature curve and the actual temperature curve may be specifically a curve showing the relationship between temperature and battery capacity. Similarly, the simulated voltage curve and the actual voltage curve may be specifically a curve showing the relationship between voltage and battery capacity.

[0117] Specifically, the preset error can be set according to the accuracy requirement. For example, the preset error of temperature can be set to 1 degree Celsius, while the preset error of voltage can be set to 30 millivolts.

[0118] If it is determined that the error between the simulated temperature curve and the actual temperature curve is not less than the corresponding preset error, or the error between the simulated voltage curve and the actual voltage curve is not less than the corresponding preset error, it means that the current error is large and needs to be optimized, so step S106 is executed at this time. If it is determined that the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than the corresponding preset error, step S107 can be executed.

[0119] A specific implementation of step S105 includes:

[0120] First, the error between the simulated voltage curve and the actual voltage curve is determined. If the error between the simulated voltage curve and the actual voltage curve is less than the corresponding preset error, then the error between the simulated temperature curve and the actual temperature curve is determined.

[0121] Since the temperature of the battery is a comprehensive parameter of heat generation and heat dissipation during operation, and the voltage will affect the heat generation of the battery, the voltage error is calibrated first to ensure that the simulated heat generation is consistent with the heat generation during the test. After that, the accurate thermal physical parameters can be obtained while ensuring the consistency of battery heat dissipation.

[0122] S106. Adjust the values ​​of target parameters in the coupling model of the target battery.

[0123] The target parameters include at least various thermophysical parameters of the target battery.

[0124] Since the error is relatively large at this time, it means that the error of each thermophysical property parameter currently determined is relatively large, so it needs to be adjusted. And after the adjustment, it is necessary to return to execute step S104.

[0125] Optionally, the value of the target parameter can be adjusted by taking the error between the simulated data and the actual data as a target and using a minimum multiplication optimization algorithm.

[0126] Optionally, in another embodiment of the present application, a specific implementation of step S106 includes:

[0127] If the error between the simulated voltage curve and the actual voltage curve is not less than the corresponding preset error, adjusting the values ​​of the thermodynamic parameters and the kinetic parameters of the battery cell in the coupling model of the target battery;

[0128] Since the voltage is mainly affected by thermodynamic parameters and kinetic parameters, the voltage curve simulated by the model is consistent with the actual curve within the preset error by adjusting the thermodynamic parameters and kinetic parameters, such as adjusting the lithium insertion state of the negative electrode material, the gram capacity of the positive and negative electrode materials, the diffusion coefficient and activation energy of the positive and negative electrodes, the reaction rate constant and activation energy, the tortuosity coefficient of the diaphragm and the electrode, and the conductivity and diffusion coefficient of the electrolyte. For example, Figure 3 , Figure 4 , Figure 5 The voltage curves under 0.33C, 1C, and 3C discharge are shown. Among them, "SIM" is the simulated data, that is, the simulated voltage curve, "EXP" is the actual test data, that is, the actual voltage curve, and "Error" indicates the error between the simulated data and the actual data. Therefore, it can be seen that by continuously adjusting the parameters, the error between the simulated data and the actual data is consistent with the preset error.

[0129] If the error between the simulated temperature curve and the actual temperature curve is not less than the corresponding preset error, each of the thermophysical property parameters in the coupling model of the target battery is adjusted.

[0130] Specifically, the temperature error is mainly caused by the error of the thermophysical parameters, so it is necessary to adjust the specific heat capacity, thickness direction thermal conductivity, and large surface thermal conductivity so that the error between the simulated temperature curve and the actual temperature curve is less than the corresponding preset error. Figure 6 As shown, by continuously adjusting the thermophysical parameters, the simulated temperature curve "Simulation" in the temperature-capacity curve approaches the actual temperature curve "Experiment", so that the error between the two is less than the preset error.

[0131] By first determining the thermodynamic parameters and kinetic parameters and then determining the thermophysical property parameters, the influence of the kinetic parameters and thermodynamic parameters on the thermophysical property parameters is reduced, thereby improving the accuracy of the thermophysical property parameters.

[0132] S107, outputting the numerical values ​​of various thermophysical property parameters in the coupling model of the current target battery.

[0133] Since the temperature and voltage errors have met the requirements at this time, it can be effectively guaranteed that the errors of the calculated thermophysical parameters are also within the required errors, so each thermophysical parameter can be output at this time. For example, as shown in the following table, the errors of the various thermophysical parameters obtained are small, which also shows that the accuracy of the method provided in the embodiment of the present application is high. Among them, for the thermophysical parameters that need to be further performed, they can be calculated based on the determined parameters, for example, the average heat generation power.

[0134]

[0135] The present application provides a method for determining the thermal physical property parameters of a battery, which performs a constant temperature charge and discharge test on a target battery under a preset test condition, and obtains the static temperature change data and the operating voltage data of the target battery. Among them, the constant temperature charge and discharge test is to charge or discharge in a constant temperature environment, and to cool statically, so the battery is heated by charging and discharging the battery, and no additional heating device is required for heating. All batteries are used, making the whole process simpler. The static temperature change data is the data of the temperature of the battery during the static cooling process, so that the convective heat transfer coefficient can be analyzed based on this. The operating voltage data is the data of the voltage of the battery during the charging or discharging process, so as to simulate the heating of the model based on this. Then, the static temperature change data of the target battery is used to fit the convective heat transfer coefficient of the target battery, and the convective heat transfer coefficient of the target battery is substituted into the coupling model of the target battery. Among them, the coupling model of the target battery is a coupling model of the electrochemical model and the heat transfer model, so that the heat lost by convective heat transfer during static cooling in a constant temperature environment is taken into account, ensuring that the thermal physical parameters of the battery can be accurately analyzed under constant temperature conditions, and static cooling in a constant temperature environment is relatively easy to achieve, so a larger constant temperature environment can be achieved at a low cost, which not only effectively reduces the cost, but also can adapt to various battery sizes. Then, according to the heat generation rate curve of the test condition, the coupling model of the target battery is heated and simulated to calculate the simulated temperature curve and the simulated voltage curve through the coupling model of the target battery. Among them, the heat generation rate curve of the test condition is calculated based on the working voltage data. Then, it is determined whether the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than the corresponding preset error. Among them, the actual temperature curve and the actual voltage curve are the temperature and voltage curves of the target battery during the charging and discharging process. If it is determined that one of the items is not less than the corresponding preset error, the value of the target parameter in the coupling model of the target battery is adjusted, and the execution is returned to perform heating simulation on the coupling model of the target battery according to the heat generation rate curve of the target condition. The target parameters at least include the various thermophysical parameters of the target battery. If both items are less than the corresponding preset errors, the values ​​of the various thermophysical parameters in the coupling model of the current target battery are output, thereby realizing a simpler and more applicable method for obtaining the thermophysical parameters of the battery.

[0136] Another embodiment of the present application provides a device for determining thermal physical property parameters of a battery, such as Figure 7 As shown, it includes the following units:

[0137] The test unit 701 is used to perform a constant temperature charge and discharge test on a target battery under a preset test condition, and obtain static temperature change data and operating voltage data of the target battery.

[0138] Among them, the constant temperature charge and discharge test is to charge or discharge in a constant temperature environment and let it cool down. The static temperature change data is the temperature data of the battery during the static cooling process. The working voltage data is the voltage data of the battery during the charging or discharging process.

[0139] The heat transfer coefficient fitting unit 702 is used to fit the convective heat transfer coefficient of the target battery using the static temperature change data of the target battery.

[0140] The substitution unit 703 is used to substitute the convection heat transfer coefficient of the target battery into the coupling model of the target battery. The coupling model of the target battery is a coupling model of an electrochemical model and a heat transfer model.

[0141] The simulation unit 704 is used to perform heating simulation on the coupling model of the target battery according to the heat generation rate curve of the test condition, so as to calculate the simulated temperature curve and the simulated voltage curve through the coupling model of the target battery. The heat generation rate curve of the test condition is calculated based on the working voltage data.

[0142] The error judgment unit 705 is used to judge whether the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than the corresponding preset errors. The actual temperature curve and the actual voltage curve are the temperature and voltage curves of the target battery during the charging and discharging process.

[0143] The adjustment unit 706 is used to adjust the value of the target parameter in the coupling model of the target battery and return it to the simulation unit when it is determined that the error between the simulated temperature curve and the actual temperature curve or the error between the simulated voltage curve and the actual voltage curve is not less than the corresponding preset error.

[0144] The output unit 707 is used to output the values ​​of each thermophysical property parameter in the coupling model of the current target battery when it is determined that the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than the corresponding preset errors.

[0145] Optionally, in a battery thermophysical property parameter determination device provided in another embodiment of the present application, the testing unit includes:

[0146] The test subunit is used to charge or discharge the target battery at a constant ambient temperature and at a preset rate corresponding to each test condition, and then cool the target battery at a constant set ambient temperature corresponding to the test condition until the temperature of the target battery drops to the set ambient temperature corresponding to the test condition. The preset test conditions include large rate test conditions and small rate test conditions.

[0147] Optionally, in the battery thermophysical property parameter determination device provided in another embodiment of the present application, the heat transfer coefficient fitting unit includes:

[0148] The parameter fitting unit is used to obtain various parameters of the target temperature function according to the static temperature change data of the target battery. Among them, the target temperature function is the result of the battery temperature being equal to the ambient temperature plus the product of the constant parameter and the target exponential term. The target exponential term is an exponential term with the negative of the heat transfer parameter and the product of time as the base. The heat transfer parameter is equal to the product of the convection heat transfer coefficient and the heat transfer area, divided by the product of the mass of the battery and the specific heat capacity.

[0149] The parameter calculation unit is used to calculate the convective heat transfer coefficient of the target battery according to the heat transfer parameters.

[0150] Optionally, in the battery thermophysical property parameter determination device provided in another embodiment of the present application, it also includes:

[0151] The model building unit is used to build a coupling model of the target battery based on the cell design parameters, thermodynamic parameters and kinetic parameters of the target battery.

[0152] The initialization unit is used to calculate the initial thermal physical parameters of the target battery based on the cell design parameters of the target battery, and substitute them into the coupling model of the target battery.

[0153] Optionally, in the battery thermophysical property parameter determination device provided in another embodiment of the present application, the adjustment unit includes:

[0154] The first adjustment unit is used to adjust the values ​​of the thermodynamic parameters and the kinetic parameters of the battery cells in the coupling model of the target battery when the error between the simulated voltage curve and the actual voltage curve is not less than the corresponding preset error.

[0155] The second adjustment unit is used to adjust various thermophysical property parameters in the coupling model of the target battery when the error between the simulated temperature curve and the actual temperature curve is not less than the corresponding preset error.

[0156] Optionally, in the battery thermophysical property parameter determination device provided in another embodiment of the present application, the error judgment unit includes:

[0157] The error judgment subunit is used to first judge the error between the simulated voltage curve and the actual voltage curve, and then judge the error between the simulated temperature curve and the actual temperature curve if the error between the simulated voltage curve and the actual voltage curve is less than the corresponding preset error.

[0158] It should be noted that the specific working process of each unit provided in the above embodiments of the present application can refer to the implementation process of the corresponding steps in the above method embodiments, and will not be repeated here.

[0159] A third aspect of the present application provides an electronic device, such as Figure 8 As shown, including:

[0160] Memory 801 and processor 802 .

[0161] The memory 801 is used to store programs.

[0162] The processor 802 is used to execute the program stored in the memory 801. When the program is executed, it is specifically used to implement the battery thermophysical property parameter determination method provided in any one of the above embodiments.

[0163] Another embodiment of the present application provides a computer storage medium for storing a computer program, which, when executed, is used to implement any of the above-mentioned methods for determining thermal physical property parameters of a battery.

[0164] Computer storage media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include temporary computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0165] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0166] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for determining battery thermal physical property parameters, characterized in that: include: Perform a constant temperature charge and discharge test on the target battery under a preset test condition, and obtain the static temperature change data and working voltage data of the target battery; wherein the constant temperature charge and discharge test is to charge or discharge in a constant temperature environment and to cool down statically; the static temperature change data is the data of the temperature of the battery during the static cooling process; the working voltage data is the data of the voltage of the battery during the charging or discharging process; Using the static temperature change data of the target battery, fitting the convective heat transfer coefficient of the target battery; Substituting the convection heat transfer coefficient of the target battery into the coupling model of the target battery; wherein the coupling model of the target battery is a coupling model of an electrochemical model and a heat transfer model; According to the heat generation rate curve of the test condition, a heating simulation is performed on the coupling model of the target battery, so as to calculate a simulated temperature curve and a simulated voltage curve through the coupling model of the target battery; wherein the heat generation rate curve of the test condition is calculated based on the operating voltage data; Determine whether the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than corresponding preset errors; wherein the actual temperature curve and the actual voltage curve are curves of temperature and voltage of the target battery during the charging and discharging process; If it is determined that the error between the simulated temperature curve and the actual temperature curve or the error between the simulated voltage curve and the actual voltage curve is not less than the corresponding preset error, the value of the target parameter in the coupling model of the target battery is adjusted, and the heat generation rate curve according to the target working condition is returned to perform heating simulation on the coupling model of the target battery; wherein the target parameter includes at least various thermophysical property parameters of the target battery; If it is determined that the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both smaller than the corresponding preset errors, the values ​​of the various thermophysical property parameters in the coupling model of the current target battery are output.

2. The method according to claim 1, characterized in that The constant temperature charge and discharge test of the target battery under the preset test conditions includes: For each of the preset test conditions, the target battery is charged or discharged at a constant ambient temperature and according to a preset rate corresponding to the test condition, and then the target battery is left to cool at a constant set ambient temperature corresponding to the test condition until the temperature of the target battery drops to the set ambient temperature corresponding to the test condition; wherein the preset test conditions include test conditions with a large rate and test conditions with a small rate.

3. The method according to claim 1, characterized in that The step of fitting the convective heat transfer coefficient of the target battery using the static temperature change data of the target battery includes: According to the target temperature function, the static temperature change data of the target battery are used to obtain various parameters of the target temperature function; wherein the target temperature function is a result of the battery temperature being equal to the ambient temperature plus the product of a constant parameter and a target exponential term; the target exponential term is an exponential term with the product of the negative of the heat transfer parameter and time as the base; the heat transfer parameter is equal to the product of the convection heat transfer coefficient and the heat transfer area, divided by the quotient obtained by the product of the mass and the specific heat capacity of the target battery; The convective heat transfer coefficient of the target battery is calculated according to the heat transfer parameters.

4. The method according to claim 1, characterized in that Also includes: Constructing a coupling model of the target battery based on the cell design parameters, thermodynamic parameters and kinetic parameters of the target battery; Based on the cell design parameters of the target battery, the initial thermophysical parameters of the target battery are calculated and substituted into the coupling model of the target battery.

5. The method according to claim 1, characterized in that The adjusting the value of the target parameter in the coupling model of the target battery includes: If the error between the simulated voltage curve and the actual voltage curve is not less than the corresponding preset error, the values ​​of the thermodynamic parameters and the kinetic parameters of the battery cell in the coupling model of the target battery are adjusted; if the error between the simulated temperature curve and the actual temperature curve is not less than the corresponding preset error, the various thermophysical parameters in the coupling model of the target battery are adjusted.

6. The method according to claim 1, characterized in that The determining whether the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than corresponding preset errors, includes: First, the error between the simulated voltage curve and the actual voltage curve is determined. If the error between the simulated voltage curve and the actual voltage curve is less than the corresponding preset error, then the error between the simulated temperature curve and the actual temperature curve is determined.

7. A device for determining battery thermal physical property parameters, characterized in that: include: A test unit, used to perform a constant temperature charge and discharge test on a target battery under a preset test condition, and obtain static temperature change data and operating voltage data of the target battery; wherein the constant temperature charge and discharge test is to charge or discharge in a constant temperature environment and to cool statically; the static temperature change data is the data of the temperature of the battery during the static cooling process; the operating voltage data is the data of the voltage of the battery during the charging or discharging process; A heat transfer coefficient fitting unit, used to fit the convective heat transfer coefficient of the target battery using the static temperature change data of the target battery; A substitution unit, used for substituting the convection heat transfer coefficient of the target battery into the coupling model of the target battery; wherein the coupling model of the target battery is a coupling model of an electrochemical model and a heat transfer model; A simulation unit, configured to perform heating simulation on the coupling model of the target battery according to the heat generation rate curve of the test condition, so as to calculate a simulated temperature curve and a simulated voltage curve through the coupling model of the target battery; wherein the heat generation rate curve of the test condition is calculated based on the operating voltage data; An error judgment unit, used to judge whether the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than corresponding preset errors; wherein the actual temperature curve and the actual voltage curve are curves of temperature and voltage of the target battery during the charging and discharging process; an adjustment unit, configured to adjust the value of the target parameter in the coupling model of the target battery and return the result to the simulation unit when it is determined that the error between the simulated temperature curve and the actual temperature curve or the error between the simulated voltage curve and the actual voltage curve is not less than the corresponding preset error; The output unit is used to output the values ​​of each of the thermophysical property parameters in the coupling model of the current target battery when it is determined that the error between the simulated temperature curve and the actual temperature curve, and the error between the simulated voltage curve and the actual voltage curve are both less than the corresponding preset errors.

8. The device according to claim 7, characterized in that The heat transfer coefficient fitting unit comprises: A parameter fitting unit, for obtaining various parameters of the target temperature function according to the static temperature change data of the target battery; wherein the target temperature function is a result of the battery temperature being equal to the ambient temperature plus the product of a constant parameter and a target exponential term; the target exponential term is an exponential term with the product of the negative of a heat transfer parameter and time as the base; the heat transfer parameter is equal to the product of a convection heat transfer coefficient and a heat transfer area, divided by the product of a mass of the battery and a specific heat capacity; A parameter calculation unit is used to calculate the convective heat transfer coefficient of the target battery according to the heat transfer parameter.

9. An electronic device, characterized in that: include: Memory and processor; Wherein, the memory is used to store programs; The processor is used to execute the program, and when the program is executed, it is specifically used to implement the battery thermal physical property parameter determination method according to any one of claims 1 to 6.

10. A computer storage medium, characterized in that: Used to store a computer program, which, when executed, is used to implement the battery thermophysical property parameter determination method according to any one of claims 1 to 6.

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