Temperature compensation calibration method and system of DCIR, computer equipment and medium

Abstract

The invention provides a DCIR temperature compensation calibration method. The DCIR temperature compensation calibration method comprises the following steps: acquiring a DCIR test value and a cell temperature of a battery cell; substituting the DCIR test value and the cell temperature into a preset temperature compensation equation constructed by taking a DCIR true value at a preset standard reference temperature as a benchmark to obtain a DCIR test value after temperature compensation calibration; wherein the preset temperature compensation equation is a nonlinear equation. Compared with the prior art, the method has the advantages that by constructing the nonlinear temperature compensation equation, the problems that the DCIR test value error is large at the non-standard temperature and the traditional linear compensation calibration precision is insufficient are solved, and the effect of improving the DCIR measurement accuracy is achieved; meanwhile, according to the calibration method disclosed by the invention, after DCIR measurement is carried out at a non-standard temperature, temperature compensation calibration is carried out on a DCIR test value, so that the effects of reducing the temperature control energy consumption of a battery production workshop and improving the test efficiency are achieved. The system has the same beneficial effects.

Description

Technical Field

[0001] The present invention belongs to the field of DCIR testing of battery cells, and in particular relates to a DCIR temperature compensation calibration method, system, computer equipment and medium. Background Art

[0002] A battery cell's direct current internal resistance (DCIR) is a key parameter for evaluating battery performance, directly impacting its energy conversion efficiency, cycle life, and safety. It is widely used in battery grading and health assessments. Accurately measuring a battery's DCIR at a standard temperature is crucial for ensuring consistent quality and reliable operation. The industry's standard temperature is typically 25°C.

[0003] During actual measurements, battery cell temperature significantly affects the DCIR value: at low temperatures, the electrolyte ionic conductivity decreases, electrode polarization intensifies, and impedance increases; at high temperatures, side reactions between the electrodes and the electrolyte accelerate, potentially causing nonlinear changes in impedance. However, battery manufacturers typically need to measure the DCIR value at a standard temperature of 25°C. Due to the limitations of temperature control accuracy in the production environment, actual DCIR measurements are often performed at a non-standard temperature of 25±3°C. Consequently, the DCIR test value calculated directly using traditional methods at this non-standard temperature deviates significantly from the actual value measured at the target standard temperature of 25°C.

[0004] The existing technology has the following problems: First, the traditional DCIR measurement method has a large error between the DCIR test value of the battery cell at non-standard temperature and the actual value measured at standard temperature, and the measurement accuracy is not high. Under normal circumstances, the error of the traditional DCIR measurement method at non-standard temperature exceeds ±10%; Second, the existing DCIR test value calibration method mostly uses linear equations for temperature compensation calibration, which has the problem of insufficient calibration accuracy.

[0005] In view of this, it is a technical problem that needs to be solved urgently by those skilled in the art to provide a temperature compensation calibration method and system for DCIR with high accuracy and small error. Summary of the Invention

[0006] In order to solve the above technical problems, the purpose of the present invention is to provide a DCIR temperature compensation calibration method. By constructing a nonlinear temperature compensation equation, the problems of large errors in DCIR test values ​​at non-standard temperatures and insufficient accuracy of traditional linear compensation calibration are solved, thereby improving the accuracy of DCIR measurement of battery cells. At the same time, the calibration method of the present invention can perform DCIR measurement at non-standard temperatures and then perform temperature compensation calibration on the DCIR test values, thereby reducing the temperature control energy consumption of the production workshop and improving test efficiency.

[0007] The object of the present invention is to provide a temperature compensation calibration method for DCIR; The technical solutions provided by the present invention are as follows: A DCIR temperature compensation calibration method comprises the following steps: Get the DCIR test value and cell temperature of the battery cell; Substituting the DCIR test value and the battery cell temperature into a preset temperature compensation equation constructed based on the DCIR true value at a preset standard reference temperature, a DCIR test value after temperature compensation calibration is obtained; wherein the preset temperature compensation equation is a nonlinear equation.

[0008] Preferably, the construction of a preset temperature compensation equation based on the true value of DCIR at a preset standard reference temperature comprises the following steps: Obtain DCIR test values ​​of multiple different batteries of the same model at multiple different battery cell temperatures, and use the DCIR test values ​​and corresponding battery cell temperatures as sample data; The preset temperature compensation equation is obtained by nonlinear regression fitting according to the sample data, the preset standard reference temperature and the DCIR true value at the preset standard reference temperature.

[0009] Preferably, obtaining the preset temperature compensation equation by nonlinear regression fitting based on the sample data, the preset standard reference temperature and the DCIR true value at the preset standard reference temperature comprises the following steps: Substituting the sample data, the preset standard reference temperature and the DCIR true value into the initial temperature compensation equation for parameter optimization to obtain a compensation coefficient and an offset value; Substituting the compensation coefficient and the offset value into the initial temperature compensation equation, the preset temperature compensation equation is obtained.

[0010] Preferably, the initial temperature compensation equation is specifically: DCIR 补偿 = DCIR 实测 +K1*(T 实测 -T 基准 ) 3+K2*(T 实测 -T 基准 ) 2 +K3*(T 实测 -T 基准 ) 1 +B; Among them, DCIR 实测 is the DCIR test value, T 实测 is the cell temperature, T 基准 is the preset standard reference temperature, K1, K2, K3 are compensation coefficients, and B is the offset value.

[0011] Preferably, obtaining the DCIR test value of the battery cell comprises the following steps: Obtaining a first voltage value V1 of the battery cell; The battery cell is discharged at a constant current, and the current of the constant current discharge is I; Obtaining a second voltage value V2 of the battery cell during constant current discharge; A DCIR test value of the battery cell is obtained according to the first voltage value V1, the current I, and the second voltage value V2.

[0012] Preferably, obtaining the DCIR test value of the battery cell according to the first voltage value V1, the current I, and the second voltage value V2 is specifically as follows: Measured DCIR = (V2-V1) / I.

[0013] Preferably, the temperature compensation calibration method is applicable to LFP lithium iron phosphate battery material system.

[0014] A DCIR temperature compensation calibration system includes: an acquisition module and a calibration module; The acquisition module is used to obtain the DCIR test value and cell temperature of the battery cell; The calibration module is used to substitute the DCIR test value and the battery cell temperature into a preset temperature compensation equation constructed based on the DCIR true value at a preset standard reference temperature to obtain a DCIR test value after temperature compensation calibration; wherein the preset temperature compensation equation is a nonlinear equation.

[0015] A third object of the present invention is to provide a computer device; The technical solutions provided by the present invention are as follows: A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the DCIR temperature compensation calibration method according to any one of claims 1 to 7 can be implemented.

[0016] A fourth object of the present invention is to provide a computer device; The technical solutions provided by the present invention are as follows: A computer-readable storage medium stores a computer program, wherein when the computer program is executed by a processor, the steps of the DCIR temperature compensation calibration method according to any one of claims 1 to 7 can be implemented.

[0017] The present invention provides a DCIR temperature compensation calibration method, comprising the following steps: obtaining a DCIR test value and cell temperature of a battery cell; substituting the DCIR test value and cell temperature into a preset temperature compensation equation constructed based on the DCIR true value at a preset standard reference temperature to obtain a DCIR test value after temperature compensation calibration; wherein the preset temperature compensation equation is a nonlinear equation. Compared to the prior art, the present invention solves the problems of large errors in DCIR test values ​​at non-standard temperatures and insufficient accuracy of traditional linear compensation calibration by constructing a nonlinear temperature compensation equation, thereby achieving the effect of improving DCIR measurement accuracy. At the same time, the calibration method of the present invention can perform temperature compensation calibration on the DCIR test value after performing DCIR measurement at non-standard temperatures, thereby reducing the temperature control energy consumption of the battery production workshop and improving testing efficiency.

[0018] The present invention also provides a DCIR temperature compensation calibration system. Since the system and the DCIR temperature compensation calibration method solve the same technical problem, belong to the same technical concept, and should have the same beneficial effects, they will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 This is a flow chart of a DCIR temperature compensation calibration method according to an embodiment of the present invention; Figure 2 This is a schematic structural diagram of a DCIR temperature compensation calibration system according to an embodiment of the present invention; Figure 3 This is a diagram of the internal structure of a computer device in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to help those skilled in the art better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of this application.

[0022] like Figure 1 As shown, an embodiment of the present invention provides a DCIR temperature compensation calibration method, comprising the following steps: S1. Obtain the DCIR test value and cell temperature of the battery cell; Preferably, obtaining the DCIR test value of the battery cell includes the following steps: A1. Obtain a first voltage value V1 of the battery cell; It should be noted that the first voltage value V1 of the battery cell is a voltage value measured without a constant current discharge.

[0023] A2. Discharge the battery cell at a constant current of I. A3, obtaining a second voltage value V2 of the battery cell during constant current discharge; A4. Obtain a DCIR test value of the battery cell according to the first voltage value V1, the current I, and the second voltage value V2.

[0024] In actual use, the battery cell temperature can be obtained by measuring it through an infrared temperature sensor or other temperature sensors, ensuring accurate measurement of the battery cell temperature value while having a relatively large measurement range.

[0025] As an implementation manner, obtaining the battery cell temperature specifically includes: when obtaining the second voltage value V2 of the battery cell during constant current discharge, measuring the battery cell temperature by using an infrared temperature measuring device.

[0026] Preferably, the DCIR test value of the battery cell is obtained according to the first voltage value V1, the current I and the second voltage value V2, specifically as follows: DCIR 实测 =(V2-V1) / I.

[0027] S2. Substitute the DCIR test value and the cell temperature into a preset temperature compensation equation constructed based on the true DCIR value at a preset standard reference temperature to obtain a DCIR test value after temperature compensation calibration; wherein the preset temperature compensation equation is a nonlinear equation.

[0028] It should be noted that the DCIR test value of the battery cell obtained in step S1 does not take into account the impact of the non-standard battery cell temperature on the DCIR test value during the DCIR measurement phase. The DCIR test value obtained in step S1 has a large error compared to the true DCIR value at the preset standard temperature. Therefore, in step S2, the DCIR test value and the battery cell temperature are substituted into a preset temperature compensation equation constructed based on the true DCIR value at the preset standard reference temperature. The DCIR test value at the non-standard temperature is calibrated to obtain the DCIR test value after temperature compensation. The true DCIR value is the DCIR value measured at the standard reference temperature. For example, if the standard reference temperature is 25°C, the DCIR value measured at this temperature is considered the true value. DCIR values ​​measured under other temperature conditions require temperature compensation and are not true values.

[0029] Compared with the existing technology, the present invention solves the problem of large errors in DCIR test values ​​at non-standard temperatures by constructing a nonlinear temperature compensation equation, thereby improving the accuracy of DCIR measurement. At the same time, the temperature compensation calibration method of the present invention can perform DCIR measurement at non-standard temperatures and then perform temperature compensation calibration on the DCIR test values, thereby reducing the temperature control energy consumption of the production workshop and improving test efficiency.

[0030] Preferably, constructing a preset temperature compensation equation based on the true value of DCIR at a preset standard reference temperature includes the following steps: B1. Obtain DCIR test values ​​for multiple batteries of the same model at multiple different cell temperatures, and use the DCIR test values ​​and corresponding cell temperatures as sample data. As an implementation method, 10 batteries of the same model are selected to perform DCIR measurement at various temperature points in the battery cell temperature range of 22°C to 28°C, and the DCIR test values ​​corresponding to each battery cell temperature are collected, wherein the selected battery cell temperatures are temperature points, such as: 22°C, 23°C...27°C, 28°C, and the DCIR test values ​​corresponding to each temperature point are obtained as sample data.

[0031] B2. Based on the sample data, the preset standard reference temperature and the true DCIR value, a preset temperature compensation equation is obtained through nonlinear regression fitting.

[0032] Preferably, a preset temperature compensation equation is obtained by nonlinear regression fitting based on the sample data, the preset standard reference temperature and the DCIR true value, comprising the following steps: B21. Substitute the sample data, the preset standard reference temperature, and the actual DCIR value into the initial temperature compensation equation to perform parameter optimization and obtain the compensation coefficient and offset value; B22. Substitute the compensation coefficient and offset value into the initial temperature compensation equation to obtain the preset temperature compensation equation.

[0033] As an implementation manner, the preset temperature compensation equation includes three compensation coefficients, namely K1, K2, and K3.

[0034] Preferably, the initial temperature compensation equation is: DCIR 补偿 = DCIR 实测 +K1*(T 实测 -T 基准 ) 3 +K2*(T 实测 -T 基准 ) 2 +K3*(T 实测 -T 基准 ) 1 +B; Among them, DCIR 实测 is the DCIR test value, T 实测 is the cell temperature, T 基准 is the preset standard reference temperature, K1, K2, K3 are compensation coefficients, and B is the offset value.

[0035] It should be noted that the temperature of each battery cell and the corresponding DCIR test value are used as sample data, and the preset standard reference temperature and the actual DCIR value at the preset standard reference temperature are used as the benchmark and substituted into the initial temperature compensation equation: DCIR 补偿 = DCIR 实测 +K1*(T 实测 -T 基准 ) 3 +K2*(T 实测 -T 基准 ) 2 +K3*(T 实测 -T 基准 ) 1 +B; The compensation coefficients K1, K2, K3 and the offset value B are obtained, and the obtained compensation coefficients and offset value are substituted into the initial temperature compensation equation to obtain the preset temperature compensation equation.

[0036] As an implementation method, a preset temperature compensation equation is obtained by nonlinear regression fitting based on sample data, a preset standard reference temperature and a true value of DCIR. Specifically, 10 LFP system batteries of the same model are selected and DCIR tests are performed at 21 temperature points, namely 15°C, 16°C, 17°C, 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C and 35°C (discharge current I=2C). At each battery cell temperature point, the DCIR is calculated based on the first voltage V1 and the second voltage V2. 实测 =(V2-V1) / I, and the results are recorded as shown in Table 1. The cell temperatures and corresponding DCIR test values ​​in Tables 1 and 2 are used as sample data, and the preset standard reference temperature is 25°C. The actual DCIR value at the preset standard reference temperature is 1.7060Ω. The initial temperature compensation equation is substituted and the parameters are optimized using the least squares method. The compensation coefficient and offset value are calculated, where K1 = 0.0002, K2 = -0.00174, K3 = -0.068, and B = 0.

[0037] Substitute the calculated compensation coefficient and offset value into the initial temperature compensation equation to obtain the preset temperature compensation equation, which is: DCIR 补偿 = DCIR 实测 +0.0002*(T 实测 -T 基准 ) 3 -0.00174*(T 实测 -T 基准 ) 2 -0.068*(T 实测 -T 基准 ) 1 .

[0038] Table 1 DCIR test value record of the same type of LFP battery in the temperature range of 15-26℃

[0039] Table 2 DCIR test value record of the same model LFP battery in the temperature range of 27-35℃

[0040] In order to verify the calibration effect of the DCIR temperature compensation calibration method of the present invention, five LFP batteries of the same model were re-selected as the verification group and numbered. The DCIR measurement values ​​of the five batteries of the same model were measured at various battery cell temperatures ranging from 15°C to 35°C and recorded. According to the preset temperature compensation equation: DCIR 补偿= DCIR 实测 +0.0002*(T 实测 -T 基准 ) 3 -0.00174*(T 实测 -T 基准 ) 2 -0.068*(T 实测 -T 基准 ) 1 .

[0041] The DCIR test values ​​after compensation calibration were calculated and compared with the actual DCIR values ​​at the standard reference temperature of 25°C to obtain Tables 3 and 4.

[0042] Table 3 Comparison of 15-26℃ DCIR compensation calibration test values ​​and standard temperature DCIR actual values

[0043] Table 427-35℃ DCIR compensation calibration test value and standard temperature DCIR actual value comparison table

[0044] The ten batteries in Table 1 are defined as the construction group, and the five batteries in Table 2 are defined as the verification group. The construction group and the verification group are DCIR tests conducted on batteries of the same model and the same battery materials using the same test equipment. Based on the data in Tables 3 and 4 above, the test results are analyzed as follows: Take verification battery pack 1 as an example: DCIR measured at a battery cell temperature of 15°C 实测 =2.3595mΩ, DCIR after compensation calibration 补偿 =1.7055mΩ (the actual DCIR value at 25°C is 1.7060mΩ, with an absolute error of 0.0005mΩ); DCIR measured at a battery cell temperature of 35°C 实测 =1.4006mΩ, DCIR after compensation calibration 补偿 =1.7066mΩ (the actual DCIR value at 25°C is 1.7060mΩ, and the absolute error is 0.0006mΩ).

[0045] Take verification battery pack 3 as an example: DCIR measured at a battery cell temperature of 17°C 实测 =2.2586mΩ, DCIR after compensation calibration 补偿=1.7056mΩ (the actual DCIR value at 25°C is 1.7060mΩ, with an absolute error of 0.0004mΩ); DCIR measured at a battery cell temperature of 33°C 实测 =1.3754mΩ, DCIR after compensation calibration 补偿 =1.7056mΩ (the actual DCIR value at 25°C is 1.7060mΩ, with an absolute error of 0.0004mΩ).

[0046] Take verification battery pack 5 as an example: DCIR measured at a battery cell temperature of 20°C 实测 =2.0647mΩ, DCIR after compensation calibration 补偿 =1.7062mΩ (the actual DCIR value at 25°C is 1.7060mΩ, with an absolute error of 0.0002mΩ); DCIR measured at a battery cell temperature of 28°C 实测 =1.5240mΩ, DCIR after compensation calibration 补偿 =1.7069 mΩ (the actual DCIR value at 25°C is 1.7060 mΩ, with an absolute error of 0.0009 mΩ).

[0047] The results show that the absolute error between the DCIR test values ​​of verification group batteries 1 to 5 after temperature compensation correction and the DCIR true values ​​at the preset standard temperature is ≤0.01mΩ, which fully meets the high-precision measurement requirements.

[0048] It should be noted that the DCIR temperature compensation calibration method of the present invention can be used to temperature compensate for DCIR test values ​​within the 15°C-35°C temperature range. In particular, compared to the existing linear temperature compensation methods, which suffer from insufficient compensation accuracy within this range, the DCIR temperature compensation calibration method of the present invention achieves high accuracy within this range, with an absolute error of ≤0.01mΩ.

[0049] In actual use, the values ​​of K1, K2, K3 and B in the preset temperature compensation equation may vary depending on the specific battery specifications and battery material system, and need to be adjusted based on the actual DCIR measurement data.

[0050] Preferably, the temperature compensation calibration method is applicable to the LFP lithium iron phosphate battery material system.

[0051] It should be noted that this method can be applied to a variety of battery material systems, including: LFP lithium iron phosphate battery material system and NCM nickel cobalt manganese battery material system.

[0052] Compared with the existing technology, the present invention effectively solves the problem of large DCIR measurement errors at non-standard temperatures through a nonlinear temperature compensation equation. It has the characteristics of high precision, wide temperature range, and the ability to perform compensation calibration for a variety of battery material systems, significantly improving the reliability and practicality of DCIR measurement of battery cells.

[0053] In one embodiment, Figure 2 As shown, a DCIR temperature compensation calibration system includes: an acquisition module and a calibration module; Acquisition module, used to obtain the DCIR test value and cell temperature of the battery cell; The calibration module is used to substitute the DCIR test value and the battery cell temperature into a preset temperature compensation equation constructed based on the DCIR true value at a preset standard reference temperature to obtain the DCIR test value after temperature compensation calibration; wherein the preset temperature compensation equation is a nonlinear equation.

[0054] Preferably, the acquisition module includes a DCIR test module and a temperature test module; DCIR test module, used to test the DCIR test value of battery cells; The temperature testing module is used to test the temperature of the battery cell.

[0055] Furthermore, the DCIR test module includes: a voltage test submodule and a current test submodule; A voltage test submodule, used to test a first voltage value V1 and a second voltage value V2 of a battery cell; The current test submodule is used to test the constant current discharge current I of the battery cell.

[0056] Furthermore, the specific working process of the DCIR test module is as follows: Testing a first voltage value V1 of the battery cell by a voltage testing submodule; Discharge the battery cell at a constant current, and test the constant current discharge current I through the current test submodule; Testing a second voltage value V2 of the battery cell during constant current discharge by the voltage testing submodule; According to the first voltage value V1, the constant current discharge current I and the second voltage value V2, the DCIR test value of the battery cell is obtained by testing. The calculation formula is as follows: DCIR 实测 =(V2-V1) / I.

[0057] It should be noted that DCIR 实测is the DCIR test value of the battery cell; the first voltage value V1 of the battery cell is the voltage value measured without a constant current discharge current.

[0058] In actual use, the battery cell temperature testing module can be: an infrared temperature sensor or other temperature sensors.

[0059] As an implementation manner, the temperature testing module is specifically configured to measure the battery cell temperature by using an infrared temperature measuring device when obtaining the second voltage value V2 of the battery cell during constant current discharge.

[0060] As an embodiment, the calibration module is specifically used to substitute the DCIR test value and the corresponding battery cell temperature into a preset temperature compensation equation constructed based on the DCIR true value at a preset standard reference temperature, to obtain a DCIR test value after temperature compensation calibration; Among them, the preset temperature compensation equation is specifically: DCIR 补偿 = DCIR 实测 +K1*(T 实测 -T 基准 ) 3 +K2*(T 实测 -T 基准 ) 2 +K3*(T 实测 -T 基准 ) 1 +B Among them, DCIR 实测 is the DCIR test value, T 实测 is the cell temperature, T 基准 is the preset standard reference temperature, K1, K2, K3 are compensation coefficients, and B is the offset value.

[0061] In actual use, the values ​​of K1, K2, K3, and B in the preset temperature compensation equation may vary depending on the specific battery specifications and battery material system, and need to be adjusted based on the actual DCIR measurement data. Therefore, before calibrating the DCIR temperature compensation calibration system of the present invention, it is necessary to first determine the values ​​of K1, K2, K3, and B in the preset temperature compensation equation according to steps B1-B2 above.

[0062] The specific definition of a DCIR temperature compensation calibration system can be found in the definition of a DCIR temperature compensation calibration method described above and will not be further elaborated here. Each module in the aforementioned DCIR temperature compensation calibration system can be implemented in whole or in part via software, hardware, or a combination thereof. Each of these modules can be embedded in or independent of a processor in a computer device in hardware form, or stored in a computer device memory in software form, allowing the processor to call and execute the corresponding operations of each module.

[0063] Those skilled in the art will understand that Figure 3 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0064] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented: Get the DCIR test value and cell temperature of the battery cell; Substitute the DCIR test value and the battery cell temperature into a preset temperature compensation equation constructed based on the true DCIR value at a preset standard reference temperature to obtain the DCIR test value after temperature compensation calibration; wherein, the preset temperature compensation equation is a nonlinear equation.

[0065] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented: Get the DCIR test value and cell temperature of the battery cell; Substitute the DCIR test value and the battery cell temperature into a preset temperature compensation equation constructed based on the true DCIR value at a preset standard reference temperature to obtain the DCIR test value after temperature compensation calibration; wherein, the preset temperature compensation equation is a nonlinear equation.

[0066] In the embodiments provided in this application, it should be understood that the disclosed methods and systems can be implemented in other ways. The system embodiments described above are merely illustrative. For example, the division of modules is merely a logical function division. In actual implementation, there may be other division methods, such as: multiple modules or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0067] As used in this application and the claims, unless the context clearly indicates an exception, the terms "a," "an," "an," and / or "the" are not intended to refer to the singular and may include the plural, unless the context clearly indicates otherwise. Generally speaking, the terms "comprises" and "include" only indicate the inclusion of the steps and elements specifically identified, and these steps and elements do not constitute an exclusive list. A method or apparatus may also include other steps or elements. The phrase "comprises a..." does not preclude the presence of additional identical elements in the process, method, product, or apparatus that includes the elements.

[0068] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. Throughout the description of this application, "plurality" or "several" means two or more, unless otherwise specifically defined.

[0069] If a flow chart is used in this application, the flow chart is used to illustrate the operations performed by the system according to the embodiments of the application. It should be understood that the previous or subsequent operations are not necessarily performed in exact order. Instead, the steps can be processed in reverse order or simultaneously. At the same time, other operations can be added to these processes, or one or more operations can be removed from these processes.

[0070] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one 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 invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A DCIR temperature compensation calibration method, characterized in that: The following steps are involved: Get the DCIR test value and cell temperature of the battery cell; Substituting the DCIR test value and the battery cell temperature into a preset temperature compensation equation constructed based on the DCIR true value at a preset standard reference temperature, a DCIR test value after temperature compensation calibration is obtained; wherein the preset temperature compensation equation is a nonlinear equation.

2. The DCIR temperature compensation calibration method according to claim 1, wherein: The method of constructing a preset temperature compensation equation based on the true value of DCIR at a preset standard reference temperature includes the following steps: Obtain DCIR test values ​​of multiple different batteries of the same model at multiple different battery cell temperatures, and use the DCIR test values ​​and corresponding battery cell temperatures as sample data; The preset temperature compensation equation is obtained by nonlinear regression fitting according to the sample data, the preset standard reference temperature and the DCIR true value at the preset standard reference temperature.

3. The DCIR temperature compensation calibration method according to claim 2, wherein: According to the sample data, the preset standard reference temperature and the DCIR true value at the preset standard reference temperature, the preset temperature compensation equation is obtained by nonlinear regression fitting, including the following steps: Substituting the sample data, the preset standard reference temperature and the DCIR true value into the initial temperature compensation equation for parameter optimization to obtain a compensation coefficient and an offset value; Substituting the compensation coefficient and the offset value into the initial temperature compensation equation, the preset temperature compensation equation is obtained.

4. The DCIR temperature compensation calibration method according to claim 3, wherein: The initial temperature compensation equation is specifically: DCIR 补偿 = DCIR 实测 +K1*(T 实测 -T 基准 ) 3 +K2*(T 实测 -T 基准 ) 2 +K3*(T 实测 -T 基准 ) 1 +B; Among them, DCIR 实测 is the DCIR test value, T 实测 is the cell temperature, T 基准 is the preset standard reference temperature, K1, K2, K3 are compensation coefficients, and B is the offset value.

5. The DCIR temperature compensation calibration method according to claim 1, wherein: The method of obtaining the DCIR test value of the battery cell includes the following steps: Obtaining a first voltage value V1 of the battery cell; The battery cell is discharged at a constant current, and the current of the constant current discharge is I; Obtaining a second voltage value V2 of the battery cell during constant current discharge; A DCIR test value of the battery cell is obtained according to the first voltage value V1, the current I, and the second voltage value V2.

6. The DCIR temperature compensation calibration method according to claim 5, wherein: The DCIR test value of the battery cell is obtained according to the first voltage value V1, the current I, and the second voltage value V2, specifically: DCIR 实测 =(V2-V1) / I.

7. The DCIR temperature compensation calibration method according to claim 1, wherein: The temperature compensation calibration method is applicable to the LFP lithium iron phosphate battery material system.

8. A DCIR temperature compensation calibration system, characterized in that: include: Acquisition module and calibration module; The acquisition module is used to obtain the DCIR test value and cell temperature of the battery cell; The calibration module is used to substitute the DCIR test value and the battery cell temperature into a preset temperature compensation equation constructed based on the DCIR true value at a preset standard reference temperature to obtain a DCIR test value after temperature compensation calibration; wherein the preset temperature compensation equation is a nonlinear equation.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the DCIR temperature compensation calibration method according to any one of claims 1 to 7 can be implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the DCIR temperature compensation calibration method according to any one of claims 1 to 7 can be implemented.

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