A solid-state battery energy storage system lumped parameter equivalent circuit parameter identification method

Abstract

The application belongs to the field of electrical testing, and provides a lumped parameter equivalent circuit parameter identification method for a solid-state battery energy storage system, which comprises the following steps: performing HPPC testing on the solid-state battery of the solid-state battery energy storage system to obtain current, temperature and stress data during discharging; calculating the force-temperature balance ratio through the temperature and stress data during discharging; obtaining the equalization equivalent current through the force-temperature balance ratio; and evaluating the battery according to the equalization equivalent current and the force-temperature balance ratio. According to the identification method of the embodiment of the application, the battery can be evaluated by combining the equalization equivalent current and the force-temperature balance ratio, the potential risks of the battery in different working states, especially the performance degradation and out-of-control risks, can be more accurately identified, serious faults of the battery can be avoided, and thus the safety and efficiency of the energy storage system are improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of electrical testing, and particularly relates to a lumped parameter equivalent circuit parameter identification method for a solid-state battery energy storage system. BACKGROUND

[0002] The existing solid-state battery evaluation method has many limitations, mainly reflected in the following aspects: first, the traditional battery evaluation method mainly relies on simple parameters such as charge-discharge times (cycle life) and state of charge (SOC), which cannot accurately reflect the changes in the electrochemical performance of the battery such as current output, internal resistance increase and capacity decay. Second, the thermal runaway and overheating risk of the battery is difficult to accurately monitor, and the existing monitoring system can only reflect the surface temperature, ignoring the relationship between the internal stress and current output of the battery. Third, the traditional method lacks depth in health evaluation under complex environmental conditions, cannot perform comprehensive evaluation in multiple dimensions, and cannot identify potential risks under different environments. Finally, the traditional battery management system (BMS) has poor real-time performance and cannot timely feedback the health status of each battery, resulting in failure to detect faults or performance degradation in the early stage. Therefore, the existing technology faces the problems of lagging battery performance degradation monitoring, inability to identify overheating risks in advance, and real-time and accuracy of health status monitoring in the energy storage system.

[0003] Due to the limitations of traditional solid-state battery evaluation technology, such as the single nature of the test device for electrical performance and the low sensitivity of the detection device for electrical faults, there are many bottlenecks in the technical route, which requires comprehensive evaluation of the battery by considering factors such as the electrochemical performance, stress distribution and thermal management of the battery through multi-dimensional analysis of electrical testing, and improving the accuracy and real-time performance of the battery management system through optimization, verification and simulation methods to provide stronger support and protection for battery health monitoring. SUMMARY

[0004] The present application aims to at least solve one of the technical problems in the related art. To this end, the purpose of the present application is to propose a lumped parameter equivalent circuit parameter identification method for a solid-state battery energy storage system, which can evaluate the battery by combining the equalization equivalent current and force-temperature balance ratio, more accurately identify the potential risks of the battery under different working conditions, especially the performance degradation and runaway risks, avoid serious faults of the battery, and thus improve the safety and efficiency of the energy storage system.

[0005] To achieve the above purpose, the present application embodiment proposes a lumped parameter equivalent circuit parameter identification method for a solid-state battery energy storage system, which comprises the following steps:

[0006] S100, performing HPPC test on the solid-state battery of the solid-state battery energy storage system to obtain the current, temperature and stress data during discharging;

[0007] S200, calculating the force-temperature balance ratio through the temperature and stress data during discharging;

[0008] S300, obtaining the balanced equivalent current through the force-temperature balance ratio;

[0009] S400, evaluating the battery according to the balanced equivalent current and the force-temperature balance ratio.

[0010] According to the identification method of the application, the battery can be evaluated by combining the balanced equivalent current and the force-temperature balance ratio, the potential risks of the battery in different working states, especially the performance degradation and out-of-control risks, can be more accurately identified, the serious failure of the battery can be avoided, and the safety and efficiency of the energy storage system can be improved; and by breaking the single limitation of the traditional electrical test device, the cross-scale diagnostic ability of the electrical fault detection device is strengthened, the energy utilization efficiency is improved, and the core safety guarantee for large-scale application of solid-state batteries is provided.

[0011] Further, in S100, the HPPC test is performed on the solid-state battery of the solid-state battery energy storage system to obtain the current, temperature and battery stress data during discharging of the battery, including:

[0012] The solid-state battery is charged to a full state of charge (SOC=100%) and left to rest until the open circuit voltage stabilizes; the parameters of the discharging pulse are set, wherein the parameters of the electrical pulse include pulse period, discharging times and current ratio, the current is measured by a Hall sensor, the temperature of the surface of the battery is collected by a multi-point temperature sensor, and the stress of the surface of the battery is collected by a stress sensor; a high-precision data acquisition system is used to synchronously record the current, temperature and battery stress data;

[0013] The solid-state battery energy storage system is an energy storage device based on solid-state battery technology; the high-precision data acquisition system is an electronic system for real-time monitoring, recording and analyzing physical quantities, which has the measurement capability of micro-volt level voltage, millisecond level time sequence and ppm level error;

[0014] Specifically, the current and temperature of the solid-state battery at each interval L of the discharge period are obtained, wherein the time interval L is set to [10, 600] seconds; YUW(j, Li) is the average temperature of the jth solid-state battery at time Li, YUY(j, Li) is the average current of the jth solid-state battery at time Li, and YUK(j, Li) is the average stress of the jth solid-state battery at time Li, wherein i is the time interval number, and j is the solid-state battery number; wherein i=1 indicates the first discharge time period, …, i=H indicates the Hth discharge time period, the median of the average temperature of the jth solid-state battery in different discharge periods is denoted as WSM(j), the median of the average current of the jth solid-state battery in different discharge periods is denoted as YSM(j), and the median of the average stress of the jth solid-state battery in different discharge periods is denoted as KSM(j).

[0015] Since the equivalent circuit parameter identification of the similar patent No. CN114781176A entitled "Equivalent circuit parameter identification method of lithium ion battery energy storage system lumped parameter" mainly relies on a model constructed by simple parameters such as charge and discharge times (cycle life) and state of charge (SOC) to perform identification, such identification often cannot accurately reflect the changes in the electrochemical performance of the battery, such as current output, internal resistance increase, and capacity decay. Secondly, the thermal runaway and overheating risk of the battery is difficult to accurately monitor. The existing monitoring system can only reflect the surface temperature, ignoring the relationship between the internal stress and the current output of the battery. Excessive current can cause a large pressure on the internal pole piece of the battery, leading to deformation of the pole piece, affecting the flow path of the internal current of the battery, further aggravating the imbalance of the internal stress, and ultimately possibly leading to performance degradation or failure of the battery. In order to solve the above problems, the present application proposes step S200;

[0016] Further, in step S200, the force-temperature balance ratio is calculated by the temperature and stress data during discharge, comprising:

[0017] Let the force-temperature balance ratio of the jth solid-state battery be KM(j), wherein KM(j)=KSM(j) / WSM(j); create an empty sequence and denote it as the force-temperature balance ratio sequence KMO; introduce all KM(j) into the force-temperature balance ratio sequence and denote the average value of the force-temperature balance ratio in the force-temperature balance ratio sequence as KMM.

[0018] The force-temperature balance ratio KM(j) is used to measure the relationship between the stress and the current of the battery in different discharge periods. When the stress of the battery is too large and the temperature is too small, or the temperature is too large and the stress is too small, KM(j) will change, reflecting the change in the performance of the battery or potential failure.

[0019] The beneficial effect of this step is that the performance degradation of the battery is often a gradual process, and the traditional method is difficult to accurately capture the early performance decline signal, and cannot effectively identify the thermal runaway or overheating problem inside the battery, and the force-temperature balance ratio can better capture the dynamic relationship between the stress and current inside the battery, and provide more accurate monitoring of the risk of thermal runaway or overheating. When the stress of the battery fails to balance in time due to excessive temperature, it may cause the deformation of the pole piece of the battery, further aggravating the stress imbalance inside the battery, thereby causing problems such as excessive temperature, thermal runaway, etc.

[0020] S300, obtaining an equalization equivalent current through the force-temperature balance ratio;

[0021] Obtaining a first force-temperature balance range K1 and a second force-temperature balance range K2 through a force-temperature balance ratio sequence;

[0022] Classifying the force-temperature balance ratio in the force-temperature balance ratio sequence KMO that is less than or equal to KMM as the first force-temperature balance range K1, and classifying the force-temperature balance ratio in the force-temperature balance ratio sequence KMO that is greater than KMM as the second force-temperature balance range K2; recording the average value under the first force-temperature balance range K1 as KO1, and the average value of the second force-temperature balance range as KO2;

[0023] Recording the average value of YSM(j) corresponding to the force-temperature balance ratio under the first force-temperature balance range K1 as TMKL, and recording the average value of YSM(j) corresponding to the force-temperature balance ratio under the second force-temperature balance range K2 as TMKP; calculating the force-temperature balance current difference LD, wherein LD is the absolute value of the difference between TMKL and TMKP;

[0024] Recording the equalization equivalent current of the jth solid-state battery as KIU(j), wherein KIU(j)=YSM(j)-LD / 2;

[0025] Wherein, the introduction of LD / 2 is to average the influence of the force-temperature balance difference on the current calculation, which can eliminate the influence of the unbalanced stress in the battery discharge process on the current output, and obtain a current value that can truly reflect the battery health status. If the stress, temperature and current of the battery are unbalanced, it will directly affect its current output capability, therefore, by subtracting half of LD in the calculation, this problem can be effectively corrected, and the calculated equalization equivalent current can truly reflect the performance of the battery under actual working conditions.

[0026] The beneficial effect of this step is that using LD / 2 can correct the influence of internal imbalance of the battery when calculating the balanced equivalent current, so as to make the health state evaluation of the battery more accurate, and help to accurately judge whether the battery has the problems of insufficient or excessive current output under different working conditions; and give a warning in the early stage of performance degradation or out-of-control of the battery. For example, due to excessive internal stress or excessive current, the battery may show the risk of performance degradation or overheating in advance, and the corrected current value can help to find these problems in time.

[0027] S400, evaluating the battery according to the balanced equivalent current and the force-temperature balance ratio;

[0028] Specifically, the evaluation of the battery of the solid-state battery energy storage system includes:

[0029] When KIU(j) is less than TMKL and TMKP at the same time and KM(j) is less than KO1, it is recorded as a performance degradation risk battery;

[0030] Specifically, KIU(j) being less than TMKL and TMKP at the same time reflects that the balanced equivalent current of the battery is too low, and the battery fails to maintain a reasonable current output during discharging. If the KM(j) of the battery is less than KO1, the force-temperature balance ratio of the battery is relatively low, and the stress of the battery fails to effectively match the current, resulting in structural problems in the battery, which leads to excessive stress and affects the discharging efficiency of the battery. When both conditions are met, it indicates that the battery shows the characteristics of insufficient current output and stress imbalance, and the battery has serious performance degradation problems and cannot effectively undertake the energy storage task, and needs to be checked and replaced in priority;

[0031] When KIU(j) is greater than TMKL and TMKP at the same time and KM(j) is greater than KO2, it is recorded as an out-of-control risk battery;

[0032] Specifically, KIU(j) being greater than TMKL and TMKP at the same time reflects that the balanced equivalent current of the battery is too high, and since the battery outputs too large current during discharging, it will produce the risk of battery overheating or over-discharge, and when the force-temperature balance ratio of the battery is too high, it indicates that the stress of the battery is too large during discharging, and the current is too high, which increases the risk of battery overheating and internal damage. When both conditions of KIU(j) being greater than TMKL and TMKP at the same time and KM(j) being greater than KO2 are met at the same time, the battery is in an over-discharge state, and the internal temperature and stress are too large, which is likely to cause serious problems such as thermal runaway, swelling and short circuit, and needs to be immediately stopped or deeply checked.

[0033] The beneficial effects of the present application are: by combining the equalization equivalent current and the force-temperature balance ratio to evaluate the battery, the potential risks of the battery in different working states, especially the performance degradation and out-of-control risks, are more accurately identified, the battery is prevented from serious failure, and the safety and efficiency of the energy storage system are improved.

[0034] This method breaks through the single limitation of traditional electrical test devices, strengthens the cross-scale diagnostic ability of electrical fault detection devices, improves energy utilization efficiency, provides core safety protection for large-scale application of solid-state batteries, and converts multi-dimensional evaluation of electricity, heat and force into executable circuit design rules through electrical testing, providing a complete solution from theory to engineering for high-reliability energy storage systems. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 The flowchart of the equivalent circuit parameter identification method of the solid-state battery energy storage system lumped parameter is shown. DETAILED DESCRIPTION

[0036] The embodiments of the present application will be described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation of the present application.

[0037] Figure 1 The flowchart of the equivalent circuit parameter identification method of the solid-state battery energy storage system lumped parameter is shown.

[0038] Referring to Figure 1 The present application proposes an equivalent circuit parameter identification method of a solid-state battery energy storage system lumped parameter, which comprises the following steps:

[0039] S100, performing HPPC test on the solid-state battery of the solid-state battery energy storage system to obtain the current, temperature and stress data during discharging;

[0040] S200, calculating the force-temperature balance ratio according to the temperature and stress data during discharging;

[0041] S300, obtaining the equalization equivalent current according to the force-temperature balance ratio;

[0042] S400, evaluating the battery according to the equalization equivalent current and the force-temperature balance ratio.

[0043] According to the identification method of the present application, the potential risks of the battery in different working states, especially the performance degradation and out-of-control risks, can be more accurately identified.

[0044] S100, performing HPPC test on the solid-state battery of the solid-state battery energy storage system to obtain the current, temperature and stress data during discharging;

[0045] The solid-state battery is charged to full state of charge (SOC=100%) and left to rest until the open circuit voltage stabilizes; the parameters of the discharge pulse are set, wherein the parameters of the electric pulse include pulse period, discharge times and current rate, the current is measured by a Hall sensor, the temperature of the battery surface is collected by a multi-point temperature sensor, and the stress of the battery surface is collected by a stress sensor; a high-precision data acquisition system is used to synchronously record the current, temperature and battery stress data;

[0046] Specifically, the current and temperature of the solid-state battery at every other discharge period L during discharging are obtained, wherein the time interval L is set to 60 seconds; YUW(j, Li) is the average temperature of the jth solid-state battery at time Li, YUY(j, Li) is the average current of the jth solid-state battery at time Li, and YUK(j, Li) is the average stress of the jth solid-state battery at time Li, wherein i is the time interval number, j is the solid-state battery number; wherein i=1 indicates the first discharge time period, …, i=H indicates the Hth discharge time period, the median of the average temperature of the jth solid-state battery in different discharge periods is denoted as WSM(j), the median of the average current of the jth solid-state battery in different discharge periods is denoted as YSM(j), and the median of the average stress of the jth solid-state battery in different discharge periods is denoted as KSM(j).

[0047] Further, in step S200, the force-temperature balance ratio is calculated by the temperature and stress data during discharging, including:

[0048] The force-temperature balance ratio of the jth solid-state battery is denoted as KM(j), wherein KM(j)=KSM(j) / WSM(j); an empty sequence is created and denoted as force-temperature balance ratio sequence KMO, all KM(j) are introduced into the force-temperature balance ratio sequence, and the average value of the force-temperature balance ratio in the force-temperature balance ratio sequence is denoted as KMM.

[0049] The force-temperature balance ratio KM(j) is used to measure the relationship between the stress and the current of the battery in different discharge periods. When the stress of the battery is too large and the temperature is too small, or the temperature is too large and the stress is too small, KM(j) will change, reflecting the change in performance or potential failure of the battery.

[0050] S300, obtaining the balanced equivalent current by the force-temperature balance ratio;

[0051] The first force-temperature balance range K1 and the second force-temperature balance range K2 are obtained by the force-temperature balance ratio sequence;

[0052] The force-temperature balance ratio in the force-temperature balance ratio sequence KMO that is less than or equal to KMM is classified as a first force-temperature balance range K1; the force-temperature balance ratio in the force-temperature balance ratio sequence KMO that is greater than KMM is classified as a second force-temperature balance range K2; the average value under the first force-temperature balance range K1 is recorded as KO1, and the average value of the second force-temperature balance range is recorded as KO2;

[0053] The average value of YSM(j) corresponding to the force-temperature balance ratio under the first force-temperature balance range K1 is recorded as TMKL, and the average value of YSM(j) corresponding to the force-temperature balance ratio under the second force-temperature balance range K2 is recorded as TMKP; a force-temperature balance current difference LD is calculated, wherein LD is the absolute value of the difference between TMKL and TMKP;

[0054] The balancing equivalent current of the jth solid-state battery is recorded as KIU(j), wherein KIU(j)=YSM(j)-LD / 2;

[0055] The introduction of LD / 2 is to average the influence of force-temperature balance difference on current calculation, which can eliminate the influence of unbalanced stress on current output during battery discharge and obtain a current value that can truly reflect the health status of the battery. If the stress, temperature and current imbalance of the battery will directly affect its current output capacity, therefore, by subtracting half of LD in the calculation, this problem can be effectively corrected, and the balancing equivalent current calculated can truly reflect the performance of the battery under actual working conditions.

[0056] S400, evaluating the battery according to the balancing equivalent current and the force-temperature balance ratio;

[0057] Specifically, evaluating the battery of the solid-state battery energy storage system includes:

[0058] When KIU(j) is less than TMKL and TMKP at the same time and KM(j) is less than KO1, the battery is recorded as a performance degradation risk battery;

[0059] Specifically, KIU(j) being less than TMKL and TMKP at the same time reflects that the balancing equivalent current of the battery is too low, and the battery fails to maintain a reasonable current output during discharge. If the KM(j) of the battery is less than KO1, the force-temperature balance ratio of the battery is relatively low, and the stress of the battery fails to effectively match the current, resulting in structural problems in the battery, which leads to too small stress and affects the discharge efficiency of the battery. When both conditions are met, it indicates that the battery shows the characteristics of insufficient current output and stress imbalance, and the battery has serious performance degradation problem and cannot effectively undertake the energy storage task, and needs to be checked and replaced in priority;

[0060] When KIU(j) is greater than TMKL and TMKP at the same time and KM(j) is greater than KO2, the battery is recorded as an out-of-control risk battery;

[0061] Specifically, KIU(j) exceeding both TMKL and TMKP indicates an excessively high balanced equivalent current in the battery. Since the battery outputs excessive current during discharge, there is a risk of overheating or over-discharge. Conversely, an excessively high force-temperature balance ratio indicates excessive stress and current during discharge, posing a risk of overheating and increased internal damage. When both KIU(j) and TMKP are simultaneously greater than KO2, the battery is in an over-discharge state with excessive internal temperature and stress, potentially leading to serious problems such as thermal runaway, expansion, and short circuits. Immediate shutdown or thorough inspection is required.

[0062] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0063] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0064] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the description of the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0065] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0066] In addition, the terms "first", "second", etc. used in the embodiments of the present application are only for the purpose of description, and cannot be understood as indicating or implying relative importance, or implicitly indicating the number of technical features indicated in the embodiments. Therefore, the features defined with "first", "second", etc. in the embodiments of the present application can be explicitly or implicitly indicated to include at least one of the features in the embodiments. In the description of the present application, the meaning of the word "plurality" is at least two or two or more, such as two, three, four, etc., unless otherwise specifically limited in the embodiments.

[0067] In the present application, unless otherwise specifically limited or defined in the embodiments, the terms "mounting", "connecting", "connecting" and "fixing" and the like appearing in the embodiments should be understood in a broad sense, for example, the connection can be a fixed connection, or a detachable connection, or integrated, which can be understood, or can be a mechanical connection, an electrical connection, etc. Of course, it can also be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two elements, or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific implementation situation.

[0068] In the present application, unless otherwise explicitly specified and limited, a first feature is "on" or "under" a second feature can mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature is "over", "above" and "on top of" the second feature can mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature. The first feature is "under", "below" and "underneath" the second feature can mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is horizontally lower than the second feature.

[0069] Although the embodiments of the present application have been shown and described above, it is to be understood that the above-described embodiments are exemplary only, and are not to be construed as limiting the present application, and that changes, modifications, substitutions and variations can be made thereto by those skilled in the art without departing from the scope of the present application.

Claims

1. A method for identifying lumped parameter equivalent circuit parameters of a solid-state battery energy storage system, characterized by, The method comprises the following steps: S100, HPPC test is performed on the solid-state battery of the solid-state battery energy storage system to obtain current, temperature and stress data during discharging, wherein the median of the average temperature of the jth solid-state battery in different discharge cycles is denoted as WSM(j), the median of the average current of the jth solid-state battery in different discharge cycles is denoted as YSM(j), and the median of the average stress of the jth solid-state battery in different discharge cycles is denoted as KSM(j); S200, the force-temperature balance ratio is calculated through the temperature and stress data during discharging; the force-temperature balance ratio of the jth solid-state battery is denoted as KM(j), wherein KM(j)=KSM(j) / WSM(j); an empty sequence is created and denoted as a force-temperature balance ratio sequence KMO, all KM(j) are introduced into the force-temperature balance ratio sequence, and the average value of the force-temperature balance ratio in the force-temperature balance ratio sequence is denoted as KMM; S300, the balanced equivalent current is obtained through the force-temperature balance ratio; the first force-temperature balance range K1 and the second force-temperature balance range K2 are obtained through the force-temperature balance ratio sequence; the force-temperature balance ratios in the force-temperature balance ratio sequence KMO that are less than or equal to KMM are classified into the first force-temperature balance range K1; the force-temperature balance ratios in the force-temperature balance ratio sequence KMO that are greater than KMM are classified into the second force-temperature balance range K2; the average value under the first force-temperature balance range K1 is denoted as KO1, and the average value of the second force-temperature balance range is denoted as KO2; the average value of YSM(j) corresponding to the force-temperature balance ratio under the first force-temperature balance range K1 is denoted as TMKL, and the average value of YSM(j) corresponding to the force-temperature balance ratio under the second force-temperature balance range K2 is denoted as TMKP; the force-temperature balance current difference LD is calculated, wherein LD is the absolute value of the difference between TMKL and TMKP; the balanced equivalent current of the jth solid-state battery is denoted as KIU(j), wherein KIU(j)=YSM(j)-LD / 2; S400, the battery is evaluated according to the balanced equivalent current and the force-temperature balance ratio.

2. The lumped parameter equivalent circuit parameter identification method of a solid state battery energy storage system according to claim 1, wherein, S100 comprises: obtaining the current and temperature of the solid-state battery during discharging every interval L during discharging, wherein the time interval L is set to [10, 600] seconds; YUW(j, Li) is the average temperature of the jth solid-state battery at time Li, YUY(j, Li) is the average current of the jth solid-state battery at time Li, and YUK(j, Li) is the average stress of the jth solid-state battery at time Li, wherein i is the time interval number, and j is the solid-state battery number.

3. The method of claim 1, wherein, S400 comprises: when KIU(j) is less than TMKL and TMKP at the same time and KM(j) is less than KO1, it is recorded as a performance degradation risk battery; when KIU(j) is greater than TMKL and TMKP at the same time and KM(j) is greater than KO2, it is recorded as an out-of-control risk battery.

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