Battery life detection and estimation method and device of energy storage system

Abstract

The embodiment of the invention provides a battery life detection and estimation method and device for an energy storage system, and the method comprises the steps: obtaining a first parameter of a battery of the energy storage system, and the first parameter comprises the charging data of the battery of the energy storage system; dividing the charging data according to time steps to obtain a charging data set; calculating the capacity of a battery of the energy storage system based on a formula 1 according to the charging data set; and estimating a first service life of the battery of the energy storage system according to the capacity of the battery of the energy storage system. According to the embodiment of the invention, the charging data of the battery of the energy storage system is collected, the charging data of the battery of the energy storage system is split according to the time step to obtain a charging data set, and the capacity of the battery of the energy storage system is calculated according to the relationship of the data in the charging data set among different data collection points. And the service life is pre-estimated based on the capacity of the battery, so that the pre-estimation accuracy is improved.

Description

Technical Field

[0001] This document relates to the technical field of energy storage systems, and in particular to a method and device for detecting and estimating the battery life of an energy storage system. Background Art

[0002] With the rapid development of renewable energy and the popularity of electric vehicles, energy storage systems are becoming increasingly important as a key link between energy production and consumption. The performance of batteries in energy storage systems, as the core components of energy storage, directly affects the efficiency and reliability of the entire system. However, batteries will experience performance degradation during use, which will directly affect the battery life and the overall performance of the energy storage system.

[0003] The life of a battery is affected by many factors. The battery will show different degradation characteristics in the early, middle and late stages of use. Traditional battery life detection and prediction methods are often based on a single battery parameter or a simple mathematical model, such as predicting the life only based on the number of cycles or remaining capacity of the battery. However, this method ignores the complexity and diversity of battery performance degradation, resulting in inaccurate prediction results.

[0004] With the continuous advancement of battery technology, the limitations of traditional prediction methods have become increasingly prominent. Batteries face more complex performance degradation mechanisms. Therefore, it is particularly important to develop a new prediction method that can comprehensively consider multiple influencing factors and accurately reflect battery degradation characteristics. Summary of the invention

[0005] The purpose of the present invention is to provide a method and device for detecting and estimating the battery life of an energy storage system, aiming to solve the above-mentioned problems in the prior art.

[0006] The present invention provides a battery life detection and estimation method for an energy storage system, comprising:

[0007] Acquire a first parameter of a battery of the energy storage system, wherein the first parameter includes charging data of the battery of the energy storage system;

[0008] Dividing the charging data according to time steps to obtain a charging data set;

[0009] According to the charging data set, the capacity of the battery of the energy storage system is calculated based on Formula 1;

[0010]

[0011] Where C represents the capacity of the battery in the energy storage system, K represents the total number of sampling points in the charging data set, k represents the number of sampling points in the charging data set, SOC(k+1) represents the state of charge of the k+1th sampling point, SOC(k) represents the state of charge of the kth sampling point, and I k+1represents the current value of the k+1th sampling point, Δt represents the time step;

[0012] A first life of the battery of the energy storage system is estimated according to the capacity of the battery of the energy storage system.

[0013] The present invention provides a battery life detection and estimation method for an energy storage system, comprising:

[0014] An acquisition module, used to acquire a first parameter of a battery of the energy storage system, wherein the first parameter includes charging data of the battery of the energy storage system;

[0015] A division module, used for dividing the charging data according to the time step to obtain a charging data set;

[0016] A calculation module, configured to calculate the capacity of a battery of the energy storage system based on the charging data set and Formula 1;

[0017]

[0018] Where C represents the capacity of the battery in the energy storage system, K represents the total number of sampling points in the charging data set, k represents the number of sampling points in the charging data set, SOC(k+1) represents the state of charge of the k+1th sampling point, SOC(k) represents the state of charge of the kth sampling point, and I k+1 represents the current value of the k+1th sampling point, Δt represents the time step;

[0019] The estimation module is used to estimate the first life of the battery of the energy storage system according to the capacity of the battery of the energy storage system.

[0020] By adopting the embodiment of the present invention, the charging data of the battery of the energy storage system is collected and split according to the time step to obtain a charging data set. According to the relationship between the data in the charging data set at different data collection points, the capacity of the battery of the energy storage system is calculated, and the life span is estimated based on the capacity of the battery, thereby improving the accuracy of the estimation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate one or more embodiments of this specification 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 some embodiments recorded in this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0022] Figure 1 is a flow chart of a method for detecting and estimating battery life of an energy storage system according to an embodiment of the present invention;

[0023] Figure 2 Schematic diagram of a battery life detection and estimation device for an energy storage system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the technical solutions in one or more embodiments of this specification, the following will be combined with the drawings in one or more embodiments of this specification to clearly and completely describe the technical solutions in one or more embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. Based on one or more embodiments of this specification, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this document.

[0025] Method Embodiment

[0026] According to an embodiment of the present invention, a method for detecting and estimating battery life of an energy storage system is provided. Figure 1 is a flow chart of a method for detecting and estimating battery life of an energy storage system according to an embodiment of the present invention. Figure 1 As shown, the battery life detection and estimation method of the energy storage system according to an embodiment of the present invention specifically includes:

[0027] Step S101, obtaining a first parameter of a battery of an energy storage system, wherein the first parameter includes charging data of the battery of the energy storage system;

[0028] Step S102, dividing the charging data according to time steps to obtain a charging data set;

[0029] Step S103, calculating the capacity of the battery of the energy storage system based on the charging data set and formula 1;

[0030]

[0031] Where C represents the capacity of the battery in the energy storage system, K represents the total number of sampling points in the charging data set, k represents the number of sampling points in the charging data set, SOC(k+1) represents the state of charge of the k+1th sampling point, SOC(k) represents the state of charge of the kth sampling point, and I k+1 represents the current value of the k+1th sampling point, Δt represents the time step;

[0032] Step S104, estimating the first life of the battery of the energy storage system according to the capacity of the battery of the energy storage system. Specifically comprising:

[0033] According to the capacity of the battery of the energy storage system, the first life of the battery of the energy storage system is estimated based on Formula 2:

[0034]

[0035] Where L1 represents the first life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the capacity of the battery of the energy storage system, C0 represents the initial capacity of the battery, K represents the total number of sampling points in the charging data set, k represents the sampling point number in the charging data set, ΔI k Represents the charging current difference between the kth sampling point and the k+1th sampling point, ΔV k represents the charging voltage difference between the kth sampling point and the k+1th sampling point, and E represents the adjustment coefficient.

[0036] The method further comprises:

[0037] Obtain the battery usage time of the energy storage system;

[0038] If the battery usage time of the energy storage system is less than or equal to a preset first threshold, then the estimation is terminated;

[0039] If the battery of the energy storage system has been in use for longer than a preset first threshold, a second parameter of the battery of the energy storage system is obtained, wherein the second parameter includes the current impedance value of the battery of the energy storage system; specifically, the method includes: applying a sinusoidal voltage or current signal of different frequencies to the battery; measuring the equivalent resistance value of the battery at different frequencies respectively; drawing an equivalent resistance spectrum according to the equivalent resistance value, and obtaining the battery impedance parameter by a fitting method; and using the battery impedance parameter to calculate and obtain the current impedance value of the battery of the energy storage system.

[0040] According to the capacity of the battery of the energy storage system and the current impedance value of the battery of the energy storage system, the second life of the battery of the energy storage system is estimated. Specifically including:

[0041] According to the capacity of the battery of the energy storage system and the current impedance value of the battery of the energy storage system, based on the public

[0042] Formula 3 estimates the second life of the battery in the energy storage system:

[0043]

[0044] Wherein, L2 represents the second life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the capacity of the battery of the energy storage system, C0 represents the initial capacity of the battery, α represents the cycle attenuation rate of capacity, β represents the cycle growth rate of impedance, Z0 represents the initial impedance value of the battery, and Z new Indicates the current impedance value of the battery.

[0045] The method further comprises:

[0046] If the battery usage time of the energy storage system is greater than a preset second threshold, a third parameter of the battery of the energy storage system is obtained, and the third parameter includes a self-discharge coefficient of the battery of the energy storage system; wherein the preset second threshold is greater than the preset first threshold; specifically including:

[0047] Disconnect the load of the fully charged battery and record the initial voltage; after maintaining the battery for a preset time, record the first voltage; and calculate the self-discharge coefficient based on the initial voltage and the first voltage. Calculating the self-discharge coefficient based on the initial voltage and the first voltage specifically includes:

[0048] The self-discharge coefficient is calculated based on the initial voltage and the first voltage according to Formula 4:

[0049]

[0050] Wherein, SDR represents the self-discharge coefficient, V0 represents the initial voltage, and V1 represents the first voltage.

[0051] According to the capacity, impedance value and self-discharge coefficient of the battery of the energy storage system, the third life of the battery of the energy storage system is estimated. Specifically including:

[0052] Based on Formula 5, the third life of the battery of the energy storage system is estimated according to the capacity, impedance value and self-discharge coefficient of the battery of the energy storage system:

[0053]

[0054] Wherein, L3 represents the third life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the battery capacity of the energy storage system, C0 represents the initial capacity of the battery, α represents the cycle attenuation rate of capacity, β represents the cycle growth rate of impedance, Z0 represents the initial impedance value of the battery, and Z end It indicates the current impedance value of the battery, and SDR indicates the self-discharge coefficient.

[0055] The above technical solution of the embodiment of the present invention is described in detail below with reference to examples.

[0056] Example 1

[0057] A battery life detection and estimation method for an energy storage system, such as Figure 1 As shown, including:

[0058] A first parameter of a battery of the energy storage system is obtained, wherein the first parameter includes charging data of the battery of the energy storage system; the first charging data includes a state of charge, a current, and a voltage corresponding to time during a charging process.

[0059] The charging data is divided according to the time step to obtain a charging data set; the acquired charging data is preprocessed, including dividing the continuously recorded charging data according to a fixed time step (such as every hour, every day or every week, etc.), so as to obtain an ordered charging data set. The time step can be determined based on factors such as the charging characteristics of the battery, the operating requirements of the energy storage system, and the frequency of data recording; when processing the data, if the data at certain time points is missing or abnormal, interpolation or correction is performed to ensure the reliability and consistency of the data set;

[0060] Calculating the capacity of the battery of the energy storage system according to the charging data set;

[0061] estimating a first life of the battery of the energy storage system according to the capacity of the battery of the energy storage system;

[0062] The capacity of the battery of the energy storage system is calculated using the following formula:

[0063]

[0064] Wherein, C represents the capacity of the battery of the energy storage system, K represents the total number of sampling points in the charging data set, k represents the sampling point number in the charging data set, SOC(k+1) represents the state of charge of the k+1th sampling point, SOC(k) represents the state of charge of the kth sampling point, Ik+1 represents the current value of the k+1th sampling point, and Δt represents the time step.

[0065] The first life of the battery of the energy storage system is estimated using the following formula:

[0066]

[0067] Where L1 represents the first life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the capacity of the battery of the energy storage system, C0 represents the initial capacity of the battery, K represents the total number of sampling points in the charging data set, k represents the sampling point number in the charging data set, ΔI k Represents the charging current difference between the kth sampling point and the k+1th sampling point, ΔV k represents the charging voltage difference between the kth sampling point and the k+1th sampling point, and E represents the adjustment coefficient. By considering the current and voltage changes during the charging process, as well as the battery capacity with a shorter usage time, the battery life can be accurately estimated, reducing the amount of data calculation.

[0068] Furthermore, in this embodiment, the method further includes:

[0069] Obtain the battery usage time of the energy storage system; the battery usage time of the energy storage system can be obtained for the initial usable time of the battery, and can be obtained based on product information. The classification can be based on the following rules: the initial use period is when the battery starts from a brand new state, and after a certain period of time, the preset first threshold, such as 1 year, is the initial use period. The length of time in the initial use period may vary depending on the battery type and the requirements of the energy storage system. The mid-use period is when the battery usage time exceeds the initial stage, and the preset second threshold is 2 years. The end of use is when the battery usage time is longer, such as more than 2 years.

[0070] Determine the relationship between the battery usage time of the energy storage system and a preset first threshold; in this embodiment, the preset first threshold is one year.

[0071] If the battery usage time of the energy storage system is less than or equal to a preset first threshold, the estimation is terminated; if the usage time is less than or equal to one year, the estimation is terminated.

[0072] If the battery of the energy storage system has been in use for a period of time greater than a preset first threshold value, and if the usage time is greater than one year, obtaining a second parameter of the battery of the energy storage system, wherein the second parameter includes a current impedance value of the battery of the energy storage system;

[0073] The second life of the battery of the energy storage system is estimated according to the capacity of the battery of the energy storage system and the current impedance value of the battery of the energy storage system.

[0074] The impedance value is obtained using the following method:

[0075] Apply a sine wave voltage or current signal of different frequencies to the battery; apply a small amplitude alternating current (AC) signal, a sine wave voltage or current signal to the battery. These signals have different frequency ranges, from low frequency (such as 0.01Hz) to high frequency (such as 10kHz or higher). By changing the frequency of the signal, the response of the battery on different time scales is collected.

[0076] The equivalent resistance of the battery is measured at different frequencies. When an AC signal is applied to the battery, the battery will exhibit a complex impedance characteristic, which includes a real part (resistance) and an imaginary part (reactance). It directly reflects the energy loss inside the battery. By measuring the voltage and current response at each frequency, the equivalent resistance at that frequency can be calculated.

[0077] Draw an equivalent resistance spectrum, and use a fitting method to obtain the impedance parameters of the battery; draw a graph of the equivalent resistance values ​​at different frequencies to obtain an equivalent resistance spectrum. This spectrum is usually presented as a curve that changes with frequency, which reflects the impedance characteristics of the battery at different frequencies. Use a fitting method, which can be based on a physical model (such as a transmission line model, Warburg impedance, etc.) or data-driven (such as a neural network, support vector machine, etc.). Decompose the complex impedance spectrum into several simple components (such as resistors, capacitors, inductors, etc.) and obtain their numerical parameters.

[0078] The impedance parameter is used to calculate and obtain the impedance value. The impedance value is synthesized using the concept of complex numbers.

[0079] In this embodiment, the second lifespan is estimated using the following formula:

[0080]

[0081] Wherein, L2 represents the second life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the capacity of the battery of the energy storage system, C0 represents the initial capacity of the battery, α represents the cycle attenuation rate of capacity, β represents the cycle growth rate of impedance, Z0 represents the initial impedance value of the battery, and Z new Indicates the current impedance value of the battery. It not only takes into account the capacity decay of the battery, but also the impact of impedance growth on the battery life, so as to more comprehensively evaluate the battery life status. The later the battery is used, the greater the impedance will be, and the greater the impact on the life will be. Therefore, when estimating the life of a battery that has been used for more than the preset first threshold, the impact of impedance is considered.

[0082] In this embodiment, the method further includes:

[0083] Determine the relationship between the battery usage time of the energy storage system and a preset second threshold value; in this embodiment, the preset second threshold value is 2 years,

[0084] If the battery of the energy storage system has been in use for a period of time greater than a preset second threshold value, and if the usage time is greater than 2 years; then obtaining a third parameter of the battery of the energy storage system, wherein the third parameter includes a self-discharge coefficient of the battery of the energy storage system;

[0085] The third life of the battery of the energy storage system is estimated according to the capacity, impedance value and self-discharge coefficient of the battery of the energy storage system.

[0086] Furthermore, in this embodiment, the self-discharge coefficient is obtained using the following method:

[0087] Disconnect the load of the fully charged battery and record the initial voltage;

[0088] After maintaining the preset time, recording the first voltage;

[0089] The self-discharge coefficient is calculated based on the initial voltage and the first voltage.

[0090] The self-discharge coefficient is calculated using the following formula:

[0091]

[0092] Wherein, SDR represents the self-discharge coefficient, V0 represents the initial voltage, and V1 represents the first voltage.

[0093] The third life of the battery is estimated using the following formula:

[0094]

[0095] Among them, L3 represents the third life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the battery capacity of the energy storage system, C0 represents the initial capacity of the battery, α represents the cycle decay rate of capacity, β represents the cycle growth rate of impedance, Z0 represents the initial impedance value of the battery, Zend represents the current impedance value of the battery, and SDR represents the self-discharge coefficient. The self-discharge coefficient usually shows an increasing trend as the battery is used in the later stage. The impact on the life is also increasing, so when estimating the life of the battery whose usage time exceeds the preset second threshold, the impact of the self-discharge coefficient is considered.

[0096] The present invention determines the relationship between the usage time and the preset first threshold and second threshold, obtains corresponding parameters for batteries in different periods, and estimates the life based on these parameters, which can more accurately reflect the performance degradation of the battery at different stages. The complexity of the battery life being affected by multiple factors is fully considered, thereby improving the accuracy of the estimation.

[0097] Device Embodiment

[0098] According to an embodiment of the present invention, a battery life detection and estimation device for an energy storage system is provided. Figure 2 is a schematic diagram of a battery life detection and estimation device for an energy storage system according to an embodiment of the present invention. Figure 2 As shown, the battery life detection and estimation device of the energy storage system according to the embodiment of the present invention specifically includes:

[0099] An acquisition module 20, configured to acquire a first parameter of a battery of the energy storage system, wherein the first parameter includes charging data of the battery of the energy storage system;

[0100] A division module 22, configured to divide the charging data according to time steps to obtain a charging data set;

[0101] A calculation module 24, configured to calculate the capacity of the battery of the energy storage system based on the charging data set and formula 1;

[0102]

[0103] Where C represents the capacity of the battery in the energy storage system, K represents the total number of sampling points in the charging data set, k represents the number of sampling points in the charging data set, SOC(k+1) represents the state of charge of the k+1th sampling point, SOC(k) represents the state of charge of the kth sampling point, and I k+1 represents the current value of the k+1th sampling point, Δt represents the time step;

[0104] The estimation module 26 is used to estimate the first life of the battery of the energy storage system according to the capacity of the battery of the energy storage system. Specifically, it includes:

[0105] According to the capacity of the battery of the energy storage system, the first life of the battery of the energy storage system is estimated based on Formula 2:

[0106]

[0107] Where L1 represents the first life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the capacity of the battery of the energy storage system, C0 represents the initial capacity of the battery, K represents the total number of sampling points in the charging data set, k represents the sampling point number in the charging data set, ΔI k Represents the charging current difference between the kth sampling point and the k+1th sampling point, ΔV k represents the charging voltage difference between the kth sampling point and the k+1th sampling point, and E represents the adjustment coefficient.

[0108] The above device further comprises:

[0109] The second life calculation module is used to obtain the battery usage time of the energy storage system; if the battery usage time of the energy storage system is less than or equal to the preset first threshold, the estimation is terminated; if the battery usage time of the energy storage system is greater than the preset first threshold, the second parameter of the battery of the energy storage system is obtained, and the second parameter includes the current impedance value of the battery of the energy storage system; according to the capacity of the battery of the energy storage system and the current impedance value of the battery of the energy storage system, the second life of the battery of the energy storage system is estimated.

[0110] Wherein, obtaining a second parameter of a battery of the energy storage system, wherein the second parameter includes a current impedance value of the battery of the energy storage system, specifically includes:

[0111] Applying sinusoidal voltage or current signals of different frequencies to the battery; and measuring the equivalent resistance values ​​of the battery at different frequencies respectively;

[0112] Draw an equivalent resistance spectrum according to the equivalent resistance value, and obtain the battery impedance parameter using a fitting method;

[0113] The battery impedance parameter is used to calculate and obtain the current impedance value of the battery of the energy storage system.

[0114] Among them, estimating the second life of the battery of the energy storage system specifically includes:

[0115] According to the capacity of the battery of the energy storage system and the current impedance value of the battery of the energy storage system, based on the public

[0116] Formula 3 estimates the second life of the battery in the energy storage system:

[0117]

[0118] Wherein, L2 represents the second life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the capacity of the battery of the energy storage system, C0 represents the initial capacity of the battery, α represents the cycle attenuation rate of capacity, β represents the cycle growth rate of impedance, Z0 represents the initial impedance value of the battery, and Z new Indicates the current impedance value of the battery.

[0119] The third life calculation module is used to obtain a third parameter of the battery of the energy storage system if the battery of the energy storage system has been in use for a period of time greater than a preset second threshold, wherein the third parameter includes a self-discharge coefficient of the battery of the energy storage system; wherein the preset second threshold is greater than the preset first threshold; and estimate the third life of the battery of the energy storage system based on the capacity, impedance value and self-discharge coefficient of the battery of the energy storage system.

[0120] Wherein, obtaining a third parameter of a battery of the energy storage system, wherein the third parameter includes a self-discharge coefficient of the battery of the energy storage system, specifically including:

[0121] Disconnect the load of the fully charged battery and record the initial voltage; after maintaining the battery for a preset time, record the first voltage; and calculate the self-discharge coefficient based on the initial voltage and the first voltage. Calculating the self-discharge coefficient based on the initial voltage and the first voltage specifically includes:

[0122] The self-discharge coefficient is calculated based on the initial voltage and the first voltage according to Formula 4:

[0123]

[0124] Wherein, SDR represents the self-discharge coefficient, V0 represents the initial voltage, and V1 represents the first voltage.

[0125] According to the capacity, impedance value and self-discharge coefficient of the battery of the energy storage system, estimating the third life of the battery of the energy storage system specifically includes:

[0126] Based on Formula 5, the third life of the battery of the energy storage system is estimated according to the capacity, impedance value and self-discharge coefficient of the battery of the energy storage system:

[0127]

[0128] Wherein, L3 represents the third life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the battery capacity of the energy storage system, C0 represents the initial capacity of the battery, α represents the cycle attenuation rate of capacity, β represents the cycle growth rate of impedance, Z0 represents the initial impedance value of the battery, and Z end It indicates the current impedance value of the battery, and SDR indicates the self-discharge coefficient.

[0129] The embodiment of the present invention is a device embodiment corresponding to the above method embodiment. The specific operations of each module can be understood by referring to the description of the method embodiment, which will not be repeated here.

[0130] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A battery life detection and estimation method for an energy storage system, characterized in that: include: Acquire a first parameter of a battery of the energy storage system, wherein the first parameter includes charging data of the battery of the energy storage system; Dividing the charging data according to time steps to obtain a charging data set; According to the charging data set, the capacity of the battery of the energy storage system is calculated based on Formula 1; Where C represents the capacity of the battery in the energy storage system, K represents the total number of sampling points in the charging data set, k represents the number of sampling points in the charging data set, SOC(k+1) represents the state of charge of the k+1th sampling point, SOC(k) represents the state of charge of the kth sampling point, and I k+1 represents the current value of the k+1th sampling point, Δt represents the time step; A first life of the battery of the energy storage system is estimated according to the capacity of the battery of the energy storage system.

2. The method according to claim 1, characterized in that: According to the capacity of the battery of the energy storage system, estimating the first life of the battery of the energy storage system specifically includes: According to the capacity of the battery of the energy storage system, the first life of the battery of the energy storage system is estimated based on Formula 2: Where L1 represents the first life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the capacity of the battery of the energy storage system, C0 represents the initial capacity of the battery, K represents the total number of sampling points in the charging data set, k represents the sampling point number in the charging data set, ΔI k Represents the charging current difference between the kth sampling point and the k+1th sampling point, ΔV k represents the charging voltage difference between the kth sampling point and the k+1th sampling point, and E represents the adjustment coefficient.

3. The method according to claim 1, characterized in that The method further comprises: Obtain the battery usage time of the energy storage system; If the battery usage time of the energy storage system is less than or equal to a preset first threshold, then the estimation is terminated; If the battery usage time of the energy storage system is greater than a preset first threshold, obtaining a second parameter of the battery of the energy storage system, wherein the second parameter includes a current impedance value of the battery of the energy storage system; The second life of the battery of the energy storage system is estimated according to the capacity of the battery of the energy storage system and the current impedance value of the battery of the energy storage system.

4. The method according to claim 3, characterized in that Acquiring a second parameter of a battery of the energy storage system, wherein the second parameter includes a current impedance value of the battery of the energy storage system and specifically includes: Applying sinusoidal voltage or current signals of different frequencies to the battery; and measuring the equivalent resistance values ​​of the battery at different frequencies respectively; Draw an equivalent resistance spectrum according to the equivalent resistance value, and obtain the battery impedance parameter using a fitting method; The battery impedance parameter is used to calculate and obtain the current impedance value of the battery of the energy storage system.

5. The method according to claim 3, characterized in that: According to the capacity of the battery of the energy storage system and the current impedance value of the battery of the energy storage system, estimating the second life of the battery of the energy storage system specifically includes: According to the capacity of the battery of the energy storage system and the current impedance value of the battery of the energy storage system, the second life of the battery of the energy storage system is estimated based on Formula 3: Wherein, L2 represents the second life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the capacity of the battery of the energy storage system, C0 represents the initial capacity of the battery, α represents the cycle attenuation rate of capacity, β represents the cycle growth rate of impedance, Z0 represents the initial impedance value of the battery, and Z new Indicates the current impedance value of the battery.

6. The method according to claim 1 or 3, characterized in that: The method further comprises: If the battery usage time of the energy storage system is greater than a preset second threshold, obtaining a third parameter of the battery of the energy storage system, wherein the third parameter includes a self-discharge coefficient of the battery of the energy storage system; wherein the preset second threshold is greater than the preset first threshold; The third life of the battery of the energy storage system is estimated according to the capacity, impedance value and self-discharge coefficient of the battery of the energy storage system.

7. The method according to claim 6, characterized in that Obtaining a third parameter of a battery of the energy storage system, wherein the third parameter includes a self-discharge coefficient of the battery of the energy storage system, specifically including: The load of the fully charged battery is disconnected, and the initial voltage is recorded; after maintaining the battery for a preset time, the first voltage is recorded; and the self-discharge coefficient is calculated based on the initial voltage and the first voltage.

8. The method according to claim 7, characterized in that Calculating the self-discharge coefficient according to the initial voltage and the first voltage specifically includes: The self-discharge coefficient is calculated based on the initial voltage and the first voltage according to Formula 4: Wherein, SDR represents the self-discharge coefficient, V0 represents the initial voltage, and V1 represents the first voltage.

9. The method according to claim 7, characterized in that: According to the capacity, impedance value and self-discharge coefficient of the battery of the energy storage system, estimating the third life of the battery of the energy storage system specifically includes: Based on Formula 5, the third life of the battery of the energy storage system is estimated according to the capacity, impedance value and self-discharge coefficient of the battery of the energy storage system: Wherein, L3 represents the third life of the battery of the energy storage system, L0 represents the initial life of the battery, C represents the battery capacity of the energy storage system, C0 represents the initial capacity of the battery, α represents the cycle attenuation rate of capacity, β represents the cycle growth rate of impedance, Z0 represents the initial impedance value of the battery, and Z end It indicates the current impedance value of the battery, and SDR indicates the self-discharge coefficient.

10. A battery life detection and estimation device for an energy storage system, characterized in that: include: An acquisition module, used to acquire a first parameter of a battery of the energy storage system, wherein the first parameter includes charging data of the battery of the energy storage system; A division module, used for dividing the charging data according to the time step to obtain a charging data set; A calculation module, configured to calculate the capacity of a battery of the energy storage system based on the charging data set and Formula 1; Where C represents the capacity of the battery in the energy storage system, K represents the total number of sampling points in the charging data set, k represents the number of sampling points in the charging data set, SOC(k+1) represents the state of charge of the k+1th sampling point, SOC(k) represents the state of charge of the kth sampling point, and I k+1 represents the current value of the k+1th sampling point, Δt represents the time step; The estimation module is used to estimate the first life of the battery of the energy storage system according to the capacity of the battery of the energy storage system.

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