Battery calendar aging estimation method and device, electronic equipment and storage medium

Abstract

The invention relates to a battery calendar aging estimation method and device, electronic equipment and a storage medium, and belongs to the technical field of battery management.The battery calendar aging estimation method comprises the steps that on the basis of SOH and calendar aging duration of a target battery at the target moment, the calendar aging speed of the target battery at the target moment is determined, the calendar aging duration is a difference value between a target moment and an initial moment, and the target moment is any moment after the initial moment; and estimating the calendar aging condition of the target battery based on the SOH of the target battery at the initial moment and the calendar aging speed of the target battery at the target moment. And the beneficial effects are briefly described. According to the invention, the complexity of the estimation process is reduced while the calendar aging estimation of the battery is realized, and the accuracy of the estimation result is improved at the same time.

Description

Technical Field

[0001] The present invention relates to the technical field of battery management, and in particular to a battery calendar aging estimation method, device, electronic equipment and storage medium. Background Art

[0002] The state of health (SOH) of a battery is generally used to indicate the degree of battery aging. Usually, the estimation of SOH is mainly based on the prediction model of calendar aging and cycle aging, and then the overall SOH value of the battery pack is predicted. The estimation of battery SOH is a very important part of the battery management system, and the calendar aging estimation is a very important part of the SOH estimation.

[0003] In the existing calendar aging estimation prediction model, the current SOH is calculated based on the collected state of charge (SOC), temperature, depth of discharge (DOD), time and current, etc., without considering the impact of calendar aging on the current SOH. Instead, the SOH is continuously calculated based on time, which will produce a large error. In addition, the estimation process of the existing calendar aging estimation prediction model is relatively complicated. Summary of the invention

[0004] In view of this, it is necessary to provide a battery calendar aging estimation method, device, electronic device and storage medium to solve the problem that the current calendar aging estimation prediction model has large errors and a complex calculation process.

[0005] In order to solve the above problems, the present invention provides a battery calendar aging estimation method, comprising: Determine the calendar aging rate of the target battery at the target time based on the SOH and calendar aging duration of the target battery at the target time, wherein the calendar aging duration is the difference between the target time and the initial time, and the target time is any time after the initial time; Based on the SOH of the target battery at the initial moment and the calendar aging rate of the target battery at the target moment, the calendar aging of the target battery is estimated.

[0006] In a possible implementation, determining the calendar aging rate of the target battery at the target time based on the SOH and calendar aging duration of the target battery at the target time includes: Based on the SOH, calendar aging duration, and calendar aging parameters of the target battery at the target moment, the calendar aging rate of the target battery at the target moment is determined. The calendar aging parameters are determined based on a calendar aging test set, which is obtained after calendar aging tests are performed on multiple sample batteries of the same model as the target battery under multiple SOC and multiple temperature conditions.

[0007] In one possible implementation, the calendar aging parameter is determined based on the following method: A target linear function is fitted based on the calendar aging test set, and the calendar aging parameter is determined based on the target linear function, wherein the target linear function takes the natural logarithm of the calendar aging duration as an independent variable and takes the natural logarithm of the SOH decay value as a dependent variable.

[0008] In a possible implementation, the expression of the target linear function is:

[0009] in, represents the SOH of the sample battery at time t, t represents the calendar aging time, Indicates the SOC of the sample battery during testing. Indicates the temperature of the sample battery during testing. , , is a constant quantity.

[0010] In a possible implementation, determining the calendar aging parameter based on the target linear function includes: The inverse of the slope of the target linear function is determined as the calendar aging parameter.

[0011] In one possible implementation, the calendar aging rate of the target battery at the target time is determined based on the following formula:

[0012] in, represents the calendar aging rate of the target battery at the target time, represents the slope of the target linear function, Indicates the SOH of the target battery at the target time, Indicates the calendar aging duration of the target battery at the target time.

[0013] In one possible implementation, the calendar aging of the target battery is estimated based on the following formula:

[0014] in, Indicates the SOH of the target battery at the target time, represents the SOH of the target battery at the initial moment, Indicates the calendar aging rate of the target battery at the target time.

[0015] The present invention also provides a battery calendar aging estimation device, comprising: A determination module, configured to determine the calendar aging speed of the target battery at the target time based on the SOH and calendar aging duration of the target battery at the target time, wherein the calendar aging duration is the difference between the target time and the initial time, and the target time is any time after the initial time; The estimation module is used to estimate the calendar aging of the target battery based on the SOH of the target battery at an initial moment and the calendar aging rate of the target battery at a target moment.

[0016] The present invention also provides an electronic device, including a memory and a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the battery calendar aging estimation method as described above is implemented.

[0017] The present invention also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the method for estimating battery calendar aging as described above is implemented.

[0018] The beneficial effects of the present invention are as follows: the battery calendar aging estimation method, device, electronic device and storage medium provided by the present invention determine the calendar aging rate of the target battery at the target moment by the SOH of the target battery at the target moment and the difference between the target moment and the initial moment, and then realize the calendar aging estimation of the target battery according to the calendar aging rate of the target battery at the target moment and the SOH of the target battery at the initial moment, without considering conditions such as SOC and temperature, thereby reducing the complexity of the calendar aging estimation, and at the same time, because the influence of the implementation of SOH on the calendar aging rate is considered during the estimation, thereby improving the accuracy of the calendar aging estimation, the present invention reduces the complexity of the estimation process while realizing the battery calendar aging estimation, and at the same time improves the accuracy of the estimation result. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of a flow chart of an embodiment of a method for estimating battery calendar aging provided by the present invention; Figure 2 A schematic diagram of a flow chart of an embodiment of a calendar aging aging rate calculation process provided by the present invention; Figure 3 A schematic diagram of a flow chart of an embodiment of a calendar aging estimation process provided by the present invention; Figure 4 A schematic diagram of the structure of an embodiment of a battery calendar aging estimation device provided by the present invention; Figure 5 A schematic structural diagram of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0020] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0021] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0022] In the description of the present invention, reference to an "embodiment" means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive of other embodiments. It is explicitly and implicitly understood by those skilled in the art that the described embodiments may be combined with other embodiments.

[0023] The SOH of a battery is generally used to indicate the degree of battery aging. Usually, the estimation of SOH is mainly based on the prediction model of calendar aging and cycle aging, and then the SOH value of the entire battery pack is predicted. The estimation of battery SOH is a very important part of the battery management system, and the calendar aging estimation is a very important part of the SOH estimation.

[0024] In the existing calendar aging estimation prediction model, the current SOH is calculated based on the collected SOC, temperature, DOD, time and current, etc., without considering the impact of calendar aging on the current SOH. Instead, the SOH is continuously calculated based on time, which will produce large errors. In addition, the estimation process of the existing calendar aging estimation prediction model is relatively complicated.

[0025] In order to solve the above problems, the present invention provides a method for estimating battery calendar aging.

[0026] The specific embodiments are described in detail below: A specific embodiment of the present invention discloses a method for estimating battery calendar aging, combining Figure 1 Come and see, Figure 1 The flowchart of an embodiment of a battery calendar aging estimation method provided by the present invention includes steps S101 to S102, wherein: In step S101, based on the SOH and calendar aging duration of the target battery at the target time, the calendar aging speed of the target battery at the target time is determined, wherein the calendar aging duration is the difference between the target time and the initial time, and the target time is any time after the initial time; In step S102, the calendar aging of the target battery is estimated based on the SOH of the target battery at the initial moment and the calendar aging rate of the target battery at the target moment.

[0027] During implementation, the SOH of the target battery at the target time (any time after the initial time) and the difference between the target time and the initial time (and the calendar aging duration) can be obtained first to determine the calendar aging speed of the target battery at the target time. Then, the calendar aging of the target battery can be estimated based on the SOH of the target battery at the initial time and the calendar aging speed of the target battery at the target time, without considering conditions such as SOC and temperature, thereby reducing the complexity of the calendar aging estimation. At the same time, since SOH is considered in the estimation process, the estimation result is more accurate.

[0028] Compared with the prior art, the battery calendar aging estimation method provided in the present embodiment determines the calendar aging rate of the target battery at the target moment through the SOH of the target battery at the target moment and the difference between the target moment and the initial moment, and then realizes the calendar aging estimation of the target battery according to the calendar aging rate of the target battery at the target moment and the SOH of the target battery at the initial moment. There is no need to consider conditions such as SOC and temperature, thereby reducing the complexity of the calendar aging estimation. At the same time, since the influence of the implementation of SOH on the calendar aging rate is considered during the estimation, the accuracy of the calendar aging estimation is improved. While realizing the battery calendar aging estimation, the present invention reduces the complexity of the estimation process and improves the accuracy of the estimation result.

[0029] Exemplarily, determining the calendar aging rate of the target battery at the target time based on the SOH and calendar aging duration of the target battery at the target time includes: Based on the SOH, calendar aging duration, and calendar aging parameters of the target battery at the target moment, the calendar aging rate of the target battery at the target moment is determined. The calendar aging parameters are determined based on a calendar aging test set, which is obtained after calendar aging tests are performed on multiple sample batteries of the same model as the target battery under multiple SOC and multiple temperature conditions.

[0030] Specifically, when determining the calendar aging speed of the target battery at the target moment according to the SOH and calendar aging duration of the target battery at the target moment, the calendar aging speed of the target battery at the target moment can be determined according to the SOH, calendar aging duration and calendar aging parameters of the target battery at the target moment. The calendar aging parameters can be determined according to a calendar aging test set, and the calendar aging test set can be obtained by performing calendar aging tests on multiple sample batteries of the same model as the target battery under multiple SOC and multiple temperature conditions.

[0031] Exemplarily, the calendar aging parameter is determined based on the following method: A target linear function is fitted based on the calendar aging test set, and the calendar aging parameter is determined based on the target linear function, wherein the target linear function takes the natural logarithm of the calendar aging duration as an independent variable and takes the natural logarithm of the SOH decay value as a dependent variable.

[0032] Specifically, when determining the calendar aging parameters according to the calendar aging test set, a target linear function with the natural logarithm of the calendar aging duration as the independent variable and the natural logarithm of the SOH attenuation value as the dependent variable can be fitted according to the calendar aging test set, and then the calendar aging parameters can be determined according to the target linear function.

[0033] Exemplarily, the expression of the target linear function is:

[0034] in, represents the SOH of the sample battery at time t, t represents the calendar aging time, Indicates the SOC of the sample battery during testing. Indicates the temperature of the sample battery during testing. , , is a constant quantity.

[0035] Specifically, the target linear function fitted according to the calendar aging test set can be expressed by the above formula.

[0036] Exemplarily, determining the calendar aging parameter based on the target linear function includes: The inverse of the slope of the target linear function is determined as the calendar aging parameter.

[0037] Specifically, when the calendar aging parameter is determined according to the target linear function, the inverse of the slope of the target linear function may be determined as the calendar aging parameter.

[0038] Exemplarily, the calendar aging rate of the target battery at the target time is determined based on the following formula:

[0039] in, represents the calendar aging rate of the target battery at the target time, represents the slope of the target linear function, Indicates the SOH of the target battery at the target time, Indicates the calendar aging duration of the target battery at the target time.

[0040] Specifically, the calendar aging rate of the target battery at the target time can be calculated by the above formula.

[0041] Exemplarily, the calendar aging of the target battery is estimated based on the following formula:

[0042] in, Indicates the SOH of the target battery at the target time, represents the SOH of the target battery at the initial moment, Indicates the calendar aging rate of the target battery at the target time.

[0043] Specifically, when estimating the calendar aging of the target battery according to the SOH of the target battery at the initial moment and the calendar aging rate of the target battery at the target moment, the calendar aging of the target battery can be estimated by the above formula.

[0044] The following is a specific application scenario to better illustrate the technical solution of the present invention: Combination Figure 2 Come and see, Figure 2 This is a flow chart of an embodiment of a calendar aging aging rate calculation process provided by the present invention. The specific steps of the process are as follows: 1. Acquisition of test data.

[0045] When the battery pack 1 and battery pack 2 were at SOC = 95% and 50%, they were placed at 25℃, 40℃, and 60℃ for 208 days, and the SOH values ​​were recorded every 2 weeks. Since SOH is calculated based on the total capacity, the total capacity value needs to be recorded when recording the SOH value. The test data can be used to reflect that the actual test result value of SOH decreases over time at different temperatures and SOCs.

[0046] 2. Data calculation.

[0047] Calculate the values ​​of ln(1-SOH) and lnt under the same SOC and temperature conditions.

[0048] 3. Calculation of linear relationships.

[0049] Calculate the linear relationship expression between ln(1-SOH) and lnt under the same SOC and temperature conditions.

[0050] 4. Linear fitting.

[0051] According to the linear relationship expression between ln(1-SOH) and lnt under multiple SOC and temperature conditions, the formula ln(1-SOH)=a*lnt+bc(SOC) / T was fitted.

[0052] 5. Calculation of aging rate based on calendar aging.

[0053] Differentiating the formula ln(1-SOH)=a*lnt+bc(SOC) / T, we can get the formula:

[0054] At the same time, from ln (1-SOH) = a * lnt + bc (SOC) / T, we can know that:

[0055] Combining the above two formulas, we can get:

[0056] Combination Figure 3 Come and see, Figure 3 This is a flow chart of an embodiment of a calendar aging estimation process provided by the present invention. The process is specifically as follows: 1. Based on the calculated calendar aging aging rate calculation formula, a calendar aging attenuation rate table (in seconds) under different initial SOH, temperature and SOC conditions is constructed.

[0057] 2. Determine the calendar aging estimation formula:

[0058] 3. According to the actual situation, query the calendar aging attenuation rate table, and estimate the calendar aging of the battery based on the calendar aging estimation formula.

[0059] The present invention can reduce the complexity of battery calendar aging estimation, and the predicted SOH at the current moment can be used to predict the SOH at the next moment, thereby improving the accuracy of the estimation result.

[0060] The embodiment of the present invention also provides a battery calendar aging estimation device, combined with Figure 4 Come and see, Figure 4 This is a schematic diagram of the structure of an embodiment of a battery calendar aging estimation device provided by the present invention. The battery calendar aging estimation device 400 includes: A determination module 401 is used to determine the calendar aging speed of the target battery at the target time based on the SOH and calendar aging duration of the target battery at the target time, wherein the calendar aging duration is the difference between the target time and the initial time, and the target time is any time after the initial time; The estimation module 402 is used to estimate the calendar aging of the target battery based on the SOH of the target battery at an initial moment and the calendar aging rate of the target battery at a target moment.

[0061] The specific implementation of each module of the battery calendar aging estimation device can refer to the description of the above-mentioned battery calendar aging estimation method, and has similar beneficial effects, which will not be repeated here.

[0062] It should be noted that the battery calendar aging estimation device can be set in the battery monitoring equipment in the machine room, and can also be set in the detection equipment of the maintenance personnel, and the present invention does not make specific limitations on this.

[0063] The embodiment of the present invention further provides an electronic device, Figure 5 Come and see, Figure 5 This is a structural diagram of an embodiment of an electronic device provided by the present invention. The electronic device 500 includes a processor 501, a memory 502, and a computer program stored in the memory 502 and executable on the processor 501. When the processor 501 executes the program, the battery calendar aging estimation method as described above is implemented.

[0064] As a preferred embodiment, the electronic device 500 further includes a display 503 for displaying that the processor 501 executes the battery calendar aging estimation method as described above.

[0065] Exemplarily, the computer program may be divided into one or more modules / units, one or more modules / units are stored in the memory 502, and are executed by the processor 501 to complete the present invention. One or more modules / units may be a series of computer program instruction segments that can complete specific functions, and the instruction segments are used to describe the execution process of the computer program in the electronic device 500. For example, the computer program may be divided into the determination module 401 and the estimation module 402 in the above embodiment, and the specific functions of each module are as described above, and are not described one by one here.

[0066] The electronic device 500 may be a desktop computer, a notebook, a PDA or a smart phone with an adjustable camera module.

[0067] Among them, the processor 501 may be an integrated circuit chip with signal processing capabilities. The above-mentioned processor 501 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present invention can be implemented or executed. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0068] The memory 502 may be, but is not limited to, a random access memory (RAM), a read only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electric erasable programmable read-only memory (EEPROM), etc. The memory 502 is used to store programs, and the processor 501 executes the program after receiving the execution instruction. The process definition method disclosed in any of the embodiments of the present invention may be applied to the processor 501 or implemented by the processor 501.

[0069] The display 503 may be an LCD display screen or an LED display screen, for example, a display screen on a mobile phone.

[0070] Understandably, Figure 5 The structure shown is only a schematic diagram of the structure of the electronic device 500. The electronic device 500 may also include Figure 5 More or fewer components as shown. Figure 5 Each component shown in the figure can be implemented by hardware, software or a combination thereof.

[0071] The electronic device provided according to the above embodiment of the present invention can be implemented with reference to the specific description of the battery calendar aging estimation method described above according to the present invention, and has similar beneficial effects as the battery calendar aging estimation method described above, which will not be described in detail here.

[0072] An embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the battery calendar aging estimation method described above is implemented.

[0073] Generally speaking, the computer instructions for implementing the method of the present invention can be carried by any combination of one or more computer-readable storage media. Non-transitory computer-readable storage media can include any computer-readable media except for the signal itself that is temporarily propagating.

[0074] Computer-readable storage media may be, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any combination thereof. More specific examples of computer-readable storage media (a non-exhaustive list) include: an electrical connection having one or more conductors, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium may be any tangible medium that contains or stores a program that may be used by or in conjunction with an instruction execution system, apparatus, or device.

[0075] Computer program codes for performing the operations of the present invention may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages, such as Java, Smalltalk, C++, and conventional procedural programming languages, such as "C" or similar programming languages, in particular, Python suitable for neural network computing and platform frameworks based on TensorFlow, PyTorch, etc. may be used. The program code may be executed entirely on the user's computer, partially on the user's computer, as an independent software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0076] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0077] The present invention discloses a battery calendar aging estimation method, device, electronic device and storage medium. The calendar aging speed of the target battery at the target moment is determined by the SOH of the target battery at the target moment and the difference between the target moment and the initial moment. Then, the calendar aging estimation of the target battery is realized according to the calendar aging speed of the target battery at the target moment and the SOH of the target battery at the initial moment. There is no need to consider conditions such as SOC and temperature, thereby reducing the complexity of the calendar aging estimation. At the same time, since the influence of the implementation of SOH on the calendar aging speed is considered during the estimation, the accuracy of the calendar aging estimation is improved. The present invention reduces the complexity of the estimation process while realizing the battery calendar aging estimation, and at the same time improves the accuracy of the estimation result.

[0078] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for estimating battery calendar aging, characterized in that: include: Determine the calendar aging rate of the target battery at the target time based on the SOH and calendar aging duration of the target battery at the target time, wherein the calendar aging duration is the difference between the target time and the initial time, and the target time is any time after the initial time; Based on the SOH of the target battery at the initial moment and the calendar aging rate of the target battery at the target moment, the calendar aging of the target battery is estimated.

2. The battery calendar aging estimation method according to claim 1, characterized in that: The step of determining the calendar aging rate of the target battery at the target time based on the SOH and calendar aging duration of the target battery at the target time includes: Based on the SOH, calendar aging duration, and calendar aging parameters of the target battery at the target moment, the calendar aging rate of the target battery at the target moment is determined. The calendar aging parameters are determined based on a calendar aging test set, which is obtained after calendar aging tests are performed on multiple sample batteries of the same model as the target battery under multiple SOC and multiple temperature conditions.

3. The method for estimating battery calendar aging according to claim 2, characterized in that: The calendar aging parameters are determined based on: A target linear function is fitted based on the calendar aging test set, and the calendar aging parameter is determined based on the target linear function, wherein the target linear function takes the natural logarithm of the calendar aging duration as an independent variable and takes the natural logarithm of the SOH decay value as a dependent variable.

4. The method for estimating battery calendar aging according to claim 3, characterized in that: The expression of the objective linear function is: in, represents the SOH of the sample battery at time t, t represents the calendar aging time, Indicates the SOC of the sample battery during testing. Indicates the temperature of the sample battery during testing. , , is a constant quantity.

5. The method for estimating battery calendar aging according to claim 4, characterized in that: The determining the calendar aging parameter based on the target linear function comprises: The inverse of the slope of the target linear function is determined as the calendar aging parameter.

6. The method for estimating battery calendar aging according to claim 5, characterized in that: The calendar aging rate of the target battery at the target time is determined based on the following formula: in, represents the calendar aging rate of the target battery at the target time, represents the slope of the target linear function, Indicates the SOH of the target battery at the target time, Indicates the calendar aging duration of the target battery at the target time.

7. The method for estimating battery calendar aging according to claim 6, characterized in that: The calendar aging of the target battery is estimated based on the following formula: in, Indicates the SOH of the target battery at the target time, represents the SOH of the target battery at the initial moment, Indicates the calendar aging rate of the target battery at the target time.

8. A battery calendar aging estimation device, characterized in that: include: A determination module, configured to determine the calendar aging speed of the target battery at the target time based on the SOH and calendar aging duration of the target battery at the target time, wherein the calendar aging duration is the difference between the target time and the initial time, and the target time is any time after the initial time; The estimation module is used to estimate the calendar aging of the target battery based on the SOH of the target battery at an initial moment and the calendar aging rate of the target battery at a target moment.

9. An electronic device, characterized in that: The invention comprises a memory and a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the method for estimating battery calendar aging according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a processor, the method for estimating battery calendar aging according to any one of claims 1 to 7 is implemented.

Images