A solid-state energy storage lithium electronic battery safety risk early warning method

Abstract

The application discloses a kind of solid-state energy storage lithium electronic battery safety risk early warning method, and the application relates to lithium electronic battery technical field, solve the problem that existing detection system is difficult to identify the internal implicit defect of battery in advance, the application is extracted by stage in overcharge process Voltage, current characteristic curve, with "change trend=voltage÷current" Electrical characterization index is constructed, realizes the accurate mapping of battery internal lithium intercalation / delithiation, impedance change and other electrochemical processes, breaks through the limitation of traditional single parameter monitoring;Design verification threshold for constant current stage, set determination standard for constant voltage stage, can accurately identify positive and negative electrode material failure, micro short circuit and lithium dendrite growth and other implicit risks, capture early warning signs of thermal runaway;Early warning logic layer by layer progresses, from characteristic curve extraction to change trend verification to abnormal signal trigger, form a complete closed loop, can respond in time in the early stage of battery safety hazard.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of lithium electronic batteries, and particularly relates to a solid-state energy storage lithium electronic battery safety risk early warning method. BACKGROUND

[0002] With the transformation of global energy structure to low carbonization and electrification, lithium ion batteries have become the core energy carrier in the fields of consumer electronics, new energy vehicles and energy storage systems due to their high energy density, long cycle life, high charging and discharging efficiency and environmental friendliness. According to industry data, the global lithium ion battery market size will exceed 1.5 trillion yuan in 2024, of which the proportion of new energy vehicle power batteries and energy storage batteries is more than 80%, and the market size is expected to further climb to more than 3 trillion yuan in 2030, showing strong development momentum.

[0003] However, while lithium ion batteries are rapidly popularizing, their safety performance is always the key bottleneck restricting the high-quality development of the industry. The complex electrochemical system composed of the positive electrode, the negative electrode, the electrolyte and the separator in the battery is prone to a series of safety hazards in the whole life cycle, such as production and manufacturing (e.g. electrode burr, electrolyte injection amount deviation), storage and transportation (e.g. high temperature and high humidity environment, severe vibration) and terminal use (e.g. overcharging and overdischarging, external impact).

[0004] From the perspective of safety accident causes, the risk of lithium ion batteries mainly comes from the thermal runaway chain reaction caused by internal electrochemical side reactions: the structure collapse of the positive electrode material releases oxygen when overcharged, which reacts with the electrolyte to generate a large amount of heat; overdischarging leads to lithium dendrite formation, which pierces the separator and causes internal short circuit; mechanical impact or extrusion causes shell damage and electrode deformation, directly damaging the structural integrity of the battery; and extreme temperature environment accelerates the decomposition of the electrolyte and the aging of the active material, reducing the thermal runaway threshold of the battery. In recent years, a number of safety incidents such as new energy vehicle self-ignition and energy storage power station fire have occurred at home and abroad, not only causing significant property losses, but also arousing widespread concern about the safety performance of lithium ion batteries in the society, and promoting the increasing demand for standardized and systematic safety detection technology in the industry.

[0005] The existing detection system still has many aspects to be improved: on the one hand, some detection methods focus on post-failure verification (such as forced short circuit and high temperature impact), which is difficult to identify the hidden defects (such as micro short circuit and local rupture of SEI film) in the battery in advance; on the other hand, with the iteration of new battery technologies such as solid-state batteries and high-nickel ternary batteries, the traditional detection parameters and judgment standards cannot fully adapt to the special electrochemical characteristics of these new battery technologies, and the detection scheme needs to be optimized accordingly.

[0006] Against this backdrop, developing a safety testing solution that covers the entire battery lifecycle, integrates multi-dimensional testing indicators, and takes into account both traditional and new battery technologies is of great practical significance for early warning of safety risks, standardizing industry quality standards, and ensuring the safe application of lithium-ion batteries in various fields. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a method for early warning of safety risks in solid-state energy storage lithium-ion batteries, solving the problem that existing detection systems struggle to identify latent internal defects in batteries in advance.

[0008] To achieve the above objectives, the present invention provides a method for early warning of safety risks in solid-state energy storage lithium-ion batteries, comprising the following steps:

[0009] Step 1: Perform an overcharge process on the lithium-ion battery, simultaneously monitoring the internal voltage of the battery in real time. If the internal voltage exceeds the set standard, then perform a constant voltage charging process until the charging current drops to the set standard. Record the characteristic curves associated with the overcharge process. The specific method is as follows:

[0010] Constant current charging is performed using a 3C current, and the internal voltage of the lithium-ion battery is monitored in real time during the charging process. The monitored internal voltage is denoted as U. i , where i represents different times;

[0011] Confirm the monitored internal voltage U i Does it satisfy: U i If the voltage is ≥1.2X rated voltage, the constant current charging process will stop; otherwise, constant current charging will continue until the internal voltage U is reached. i Stop when the condition is met, and the rated voltage is the preset voltage;

[0012] Internal voltage U i When the condition is met, the current charging voltage is kept constant, and the charging current is monitored in real time. When the charging current drops to 0.05C, charging is stopped. The time period associated with this overcharge process is confirmed, and the current change curve and voltage change curve generated by the lithium-ion battery within this time period are confirmed. The confirmed change curves are recorded as the characteristic curves associated with this overcharge process.

[0013] Step 2: Extract the characteristic curves of the constant current charging stage from the characteristic curves confirmed during the overcharging process. Then, confirm the constant current change trend from the extracted characteristic curves, and verify the confirmed constant current change trend in sequence. Based on the verification results, confirm whether the constant current charging stage is normal. The specific method is as follows:

[0014] During the constant current charging process, identify the relevant time period T1 from the start of charging to the moment when the internal voltage of the lithium-ion battery reaches the rated voltage, and then confirm the rise of the internal voltage of the lithium-ion battery from the rated voltage to U. i The associated time period T2, where T1 and T2 are both single time periods;

[0015] Extract the two sets of partial characteristic curves included in the associated time period T1 from the two sets of characteristic curves, extract the voltage and current associated at the same moment, and use: change trend = voltage ÷ current to confirm the change trend associated at the corresponding moment. Based on the time direction from the initial moment to the end moment of the associated time period T1, generate the trend change curve of the corresponding change trend, which is recorded as the initial curve.

[0016] For the two sets of characteristic curves associated with the associated time period T2, the same initial curve determination method is used to generate the corresponding trend curve of the associated change within the associated time period T2, which is denoted as the secondary curve;

[0017] The confirmed initial curve and secondary curve are both recorded as curves to be processed. The variation characteristics of adjacent points between adjacent time points are determined, and the variation trend of the point after the adjacent point is defined as Q1, and the variation trend of the point before the adjacent point as Q2. Their variation characteristics are defined as Q1 - Q2. Curve segments with consistent variation characteristics are recorded as segments with the same variation. These segments with the same variation are sequentially determined within the curves to be processed, and the variation characteristics of each segment are recorded as B. k , where k represents different segments of the same variation within the curve to be processed;

[0018] Within the initial curve, several B's k Perform mean processing to determine the characteristic mean, and then use: CZ k =|B k - Feature mean | Confirm corresponding B k The associated deviation value CZ k From the confirmed deviation values ​​CZ k In the process, the maximum value is selected, and the segment of change associated with the maximum value is recorded as the segment to be verified in the initial curve; the same method of determining the segment to be verified in the initial curve is used to determine the segment to be verified associated in the secondary curve.

[0019] The change characteristics of the segment to be verified within the initial curve are denoted as B1, and the change characteristics of the segment to be verified within the secondary curve are denoted as B2. It is evaluated whether B1 and B2 satisfy the condition: (B1-B2)÷B1≥100%. If they satisfy the condition, it indicates that there is an abnormality in the constant current charging process, and a safety abnormality signal is directly generated for display. Otherwise, the subsequent verification process is executed.

[0020] Step 3: Extract the characteristic curve of the constant voltage charging stage from the characteristic curves confirmed during the overcharging process, confirm the constant voltage change trend from the extracted characteristic curves, and confirm the overall trend difference from the confirmed constant voltage change trend. Assess whether the constant voltage charging stage is normal based on the confirmed overall trend difference. The specific method is as follows:

[0021] During the constant voltage charging phase, it was confirmed that the internal voltage reached U. i The moment when the charging current drops to 0.05C is recorded as the initial moment, and the moment when the charging current drops to 0.05C is recorded as the end moment. The time period between the initial moment and the end moment is recorded as the associated time period.

[0022] Extract the two sets of partial characteristic curves associated with the two sets of characteristic curves within the associated time period, and extract the voltage and current associated at the same moment from the two sets of partial characteristic curves. Then, use the formula: Change Trend = Voltage ÷ Current to confirm the change trend associated at the corresponding moment. Based on the time direction of the associated time period, generate the trend change curve of the change trend, which is recorded as the undetermined curve.

[0023] In the curve to be determined, the change characteristics of adjacent points between adjacent time points are determined, and the curve segments with consistent change characteristics are denoted as segments with the same change characteristics. The segments with the same change characteristics associated with each other in the curve to be processed are determined sequentially, and the change characteristics of each segment with the same change characteristics are denoted as Z. q , where q represents different segments of the same change within the curve to be determined;

[0024] From the identified set of change characteristics Z q Select the maximum value Z q max and minimum value Z q min, identify Z q max and Z q Does min satisfy: (Z) q max-Z q min)÷Z q If the maximum percentage (Z) is greater than or equal to 50%, a safety anomaly signal will be generated and displayed directly; otherwise, the confirmed percentage parameter "(Z)" will be used. q max-Z q min)÷Z q The display will show "max".

[0025] This invention provides a method for early warning of safety risks in solid-state energy storage lithium-ion batteries. Compared with existing technologies, it has the following advantages:

[0026] Firstly, by extracting the voltage and current characteristic curves during the overcharging process in stages, and constructing an electrical characterization index based on "change trend = voltage ÷ current", the system achieves accurate mapping of electrochemical processes such as lithium insertion / deintercalation and impedance changes within the battery, breaking through the limitations of traditional methods that rely solely on monitoring a single parameter.

[0027] Secondly, the design of verification thresholds for the constant current stage and the setting of judgment criteria for the constant voltage stage can accurately identify hidden risks such as failure of positive and negative electrode materials, micro-short circuits and lithium dendrite growth, and capture early signs of thermal runaway.

[0028] Third, the early warning logic is progressive, from feature curve extraction to trend verification and abnormal signal triggering, forming a complete closed loop. It can respond in a timely manner at the initial stage of battery safety hazards, effectively avoiding serious accidents such as fires and explosions, and providing scientific and efficient protection for the safe operation of solid-state energy storage lithium batteries. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the method flow of the present invention. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Please see Figure 1 This application provides a method for early warning of safety risks in solid-state energy storage lithium-ion batteries, comprising the following steps:

[0032] Step 1: Perform an overcharge process on the lithium-ion battery. Charge it with a constant current of 3C and monitor the internal voltage of the lithium-ion battery in real time. When the internal voltage exceeds the set standard, perform a constant voltage charging process until the charging current drops to the set standard. Record the characteristic curves associated with the overcharge process.

[0033] The specific method for recording the characteristic curve is as follows:

[0034] An overcharge process is performed on the lithium-ion battery, using a constant current charging process at 3C. During the charging process, the internal voltage of the lithium-ion battery is monitored in real time, and the monitored internal voltage is denoted as U. i , where i represents different times;

[0035] Confirm the monitored internal voltage U i Does it satisfy: U iIf the voltage is ≥1.2X rated voltage, the constant current charging process will stop; otherwise, constant current charging will continue until the internal voltage U is reached. i Stop when the condition is met; the rated voltage is a preset voltage, which is determined in advance by relevant personnel according to the instructions.

[0036] Internal voltage U i When the condition is met, the current charging voltage is kept constant, and the charging current is monitored in real time. When the charging current drops to 0.05C, charging is stopped. The time period associated with this overcharge process is confirmed, and the current change curve and voltage change curve generated by the lithium-ion battery within this time period are confirmed. The confirmed change curves are recorded as the characteristic curves associated with this overcharge process.

[0037] Specifically, during the overcharging process, lithium-ion batteries typically undergo two charging stages: a constant current charging stage and a constant voltage charging stage. In the constant current charging stage, the potential difference (battery terminal voltage) continuously increases, driven primarily by the lithium insertion / deintercalation process at the electrodes: as the amount of lithium inserted into the positive electrode increases and the amount of lithium deintercalated from the negative electrode increases, the potential difference between the positive and negative electrode surfaces gradually widens, resulting in a linear or stepwise increase in the terminal voltage. During this stage, the current remains constant, and the change in potential difference mainly stems from the change in the electrochemical state of the active material, with relatively small changes in internal resistance.

[0038] During the constant-voltage charging phase, the potential difference remains constant, and the current decreases due to the dynamic equilibrium of polarization: after the voltage is fixed, the lithium-ion transport rate inside the battery decreases with the degree of lithium intercalation saturation, and the degree of polarization intensifies, causing the charging current to gradually decrease to 0.05C. During this phase, the potential difference no longer changes, and the battery's full-charge process is only reflected by the current decay.

[0039] Therefore, during the corresponding constant current charging stage and constant voltage charging stage, the current and voltage curves inside the lithium-ion battery will change accordingly. Based on the change process of the corresponding parameters, the corresponding overcharge process and the associated change curves can be identified.

[0040] Step 2: Extract the characteristic curves of the constant current charging stage from the characteristic curves confirmed during the overcharging process. Then, confirm the constant current change trend from the extracted characteristic curves, and verify the confirmed constant current change trend in sequence. Based on the verification results, confirm whether the constant current charging stage is normal.

[0041] During the constant current charging process, identify the relevant time period T1 from the start of charging to the moment when the internal voltage of the lithium-ion battery reaches the rated voltage, and then confirm the rise of the internal voltage of the lithium-ion battery from the rated voltage to U. i The associated time period T2, where T1 and T2 are both individual time periods, do not represent a specific moment;

[0042] Extract the two sets of partial characteristic curves included in the associated time period T1 from the two sets of characteristic curves. Extract the voltage and current associated at the same moment and use the formula: change trend = voltage ÷ current to confirm the change trend associated at the corresponding moment. The change trend here can be understood as a relative rate of change of the amount of lithium inserted into the positive electrode and the amount of lithium removed from the negative electrode. As the charging time increases, corresponding chemical changes will occur between the two positive and negative electrodes. This change trend can be understood as the impedance change caused by the corresponding chemical change. More accurately, it is an electrical characterization index reflecting the chemical change. Based on the time trend from the initial moment to the end moment of the associated time period T1, generate the trend change curve of the corresponding change trend, which is denoted as the initial curve.

[0043] For the two sets of characteristic curves associated with the associated time period T2, the same initial curve determination method is used to generate the change curve of the associated change trend within the corresponding associated time period T2, which is denoted as the secondary curve;

[0044] The confirmed initial curve and secondary curve are both recorded as curves to be processed. The variation characteristics of adjacent points between adjacent time points are determined, and the variation trend of the point after the adjacent point is defined as Q1, and the variation trend of the point before the adjacent point as Q2. Their variation characteristics are defined as Q1 - Q2. Curve segments with consistent variation characteristics are recorded as segments with the same variation. These segments with the same variation are sequentially determined within the curves to be processed, and the variation characteristics of each segment are recorded as B. k , where k represents different segments of the same variation within the curve to be processed;

[0045] Within the initial curve, several B's k Perform mean processing to determine the characteristic mean, and then use: CZ k =|B k - Feature mean | Confirm corresponding B k The associated deviation value CZ k From the confirmed deviation values ​​CZ k In the process, the maximum value is selected, and the segment of change associated with the maximum value is recorded as the segment to be verified in the initial curve; the same method of determining the segment to be verified in the initial curve is used to determine the segment to be verified associated in the secondary curve.

[0046] The change characteristics of the segment to be verified within the initial curve are denoted as B1, and the change characteristics of the segment to be verified within the secondary curve are denoted as B2. The evaluation is based on whether B1 and B2 satisfy the condition: (B1-B2)÷B1≥100%. If satisfied, it indicates an anomaly during constant current charging, and a safety anomaly signal is directly generated for display. If not satisfied, the subsequent verification process is executed for reconfirmation. When this condition is met, it proves that the subsequent trend of change in the full-charge process is opposite to the trend of change at the beginning. Under normal circumstances, they should be consistent. If the difference in core change characteristics between the two time periods exceeds 100%, it indicates a trend reversal or drastic fluctuation in the lithium insertion / deintercalation process of the positive and negative electrodes, which may be caused by positive electrode lattice damage, negative electrode SEI film rupture, or internal micro-short circuit. In severe cases, it may even lead to an explosion. Therefore, it is necessary to promptly display the anomaly signal in real time.

[0047] Step 3: Extract the characteristic curve of the constant voltage charging stage from the characteristic curves confirmed during the overcharging process, confirm the constant voltage change trend from the extracted characteristic curves, and confirm the overall trend difference from the confirmed constant voltage change trend. Assess whether the constant voltage charging stage is normal based on the confirmed overall trend difference.

[0048] During the constant voltage charging phase, it was confirmed that the internal voltage reached U. i The moment when the charging current drops to 0.05C is recorded as the initial moment, and the moment when the charging current drops to 0.05C is recorded as the end moment. The time period between the initial moment and the end moment is recorded as the associated time period.

[0049] Extract the two sets of partial characteristic curves associated with the two sets of characteristic curves within the associated time period, and extract the voltage and current associated at the same moment from the two sets of partial characteristic curves. Then, use the formula: Change Trend = Voltage ÷ Current to confirm the change trend associated at the corresponding moment. Based on the time direction of the associated time period, generate the trend change curve of the change trend, which is recorded as the undetermined curve.

[0050] In the curve to be determined, the change characteristics of adjacent points between adjacent time points are determined, and the curve segments with consistent change characteristics are denoted as segments with the same change characteristics. The segments with the same change characteristics associated with each other in the curve to be processed are determined sequentially, and the change characteristics of each segment with the same change characteristics are denoted as Z. q , where q represents different segments of the same change within the curve to be determined;

[0051] From the identified set of change characteristics Z q Select the maximum value Z q max and minimum value Z q min, identify Z q max and Z q Does min satisfy: (Z) q max-Z q min)÷Zq If the maximum percentage (Z) is greater than or equal to 50%, a safety anomaly signal will be generated and displayed directly. Otherwise, the confirmed percentage parameter "(Z)" will be displayed. q max-Z q min)÷Z q Display using "max";

[0052] Specifically, when the corresponding ratio parameter exceeds 50%, it means that there are already hidden defects in the early constant current stage (such as micro short circuits or SEI film rupture). Continuous charging in the constant voltage stage will aggravate the growth of lithium dendrites, eventually piercing the separator and causing a short circuit. The electrolyte will continue to decompose and produce gas at high potential. When the shell cannot withstand the gas pressure, it will rupture. If the gas mixes with air and encounters a spark, it may cause an explosion. Therefore, it is necessary to display the signal in time to provide a safety warning.

[0053] Some of the data in the above formulas are numerical calculations with dimensions removed, and the contents not described in detail in this specification are all prior art known to those skilled in the art.

[0054] The above embodiments are only used to illustrate the technical methods of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical methods of the present invention without departing from the spirit and scope of the technical methods of the present invention.

Claims

1. A method for early warning of safety risks in solid-state energy storage lithium-ion batteries, characterized in that, Includes the following steps: Step 1: Perform an overcharge process on the lithium-ion battery, simultaneously monitoring the internal voltage of the battery in real time. If the internal voltage exceeds the set standard, then perform a constant voltage charging process until the charging current drops to the set standard. Record the characteristic curves associated with the overcharge process. The specific method is as follows: Constant current charging is performed using a 3C current, and the internal voltage of the lithium-ion battery is monitored in real time during the charging process. The monitored internal voltage is denoted as U. i , where i represents different times; Confirm the monitored internal voltage U i Does it satisfy: U i If the voltage is ≥1.2 × rated voltage, the constant current charging process will stop; otherwise, constant current charging will continue until the internal voltage U is reached. i Stop when the condition is met, and the rated voltage is the preset voltage; Internal voltage U i When the condition is met, the current charging voltage is kept constant, and the charging current is monitored in real time. When the charging current drops to 0.05C, charging is stopped. The time period associated with this overcharge process is confirmed, and the current change curve and voltage change curve generated by the lithium-ion battery within this time period are confirmed. The confirmed change curves are recorded as the characteristic curves associated with this overcharge process. Step 2: Extract the characteristic curve of the constant current charging stage from the characteristic curves confirmed during the overcharging process, then confirm the constant current change trend from the extracted characteristic curves, and verify the confirmed constant current change trend in turn. Based on the verification results, confirm whether the constant current charging stage is normal. Step 3: Extract the characteristic curve of the constant voltage charging stage from the characteristic curves confirmed during the overcharging process, confirm the constant voltage change trend from the extracted characteristic curves, confirm the overall trend difference from the confirmed constant voltage change trend, and assess whether the constant voltage charging stage is normal based on the confirmed overall trend difference.

2. The method for early warning of safety risks in solid-state energy storage lithium-ion batteries according to claim 1, characterized in that, In step two, the specific method for confirming the constant current change trend from the extracted feature curves is as follows: During the constant current charging process, identify the relevant time period T1 from the start of charging to the moment when the internal voltage of the lithium-ion battery reaches the rated voltage, and then confirm the rise of the internal voltage of the lithium-ion battery from the rated voltage to U. i The associated time period T2, where T1 and T2 are both single time periods; Extract the two sets of partial characteristic curves included in the associated time period T1 from the two sets of characteristic curves, extract the voltage and current associated at the same moment, and use: change trend = voltage ÷ current to confirm the change trend associated at the corresponding moment. Based on the time direction from the initial moment to the end moment of the associated time period T1, generate the trend change curve of the corresponding change trend, which is recorded as the initial curve. For the two sets of characteristic curves associated with the associated time period T2, the same initial curve determination method is used to generate the change curve of the associated change trend within the corresponding associated time period T2, which is denoted as the secondary curve.

3. The method for early warning of safety risks in solid-state energy storage lithium-ion batteries according to claim 2, characterized in that, In step two, the specific method for confirming whether the constant current charging stage is normal is as follows: The confirmed initial curve and secondary curve are both recorded as curves to be processed. The variation characteristics of adjacent points between adjacent time points are determined, and the variation trend of the point after the adjacent point is defined as Q1, and the variation trend of the point before the adjacent point as Q2. Their variation characteristics are defined as Q1 - Q2. Curve segments with consistent variation characteristics are recorded as segments with the same variation. These segments with the same variation are sequentially determined within the curves to be processed, and the variation characteristics of each segment are recorded as B. k , where k represents different segments of the same variation within the curve to be processed; Within the initial curve, several B's k Perform mean processing to determine the characteristic mean, and then use: CZ k =|B k - Feature mean | Confirm corresponding B k The associated deviation value CZ k From the confirmed deviation values ​​CZ k In the process, the maximum value is selected, and the segment of change associated with the maximum value is recorded as the segment to be verified in the initial curve; the same method of determining the segment to be verified in the initial curve is used to determine the segment to be verified associated in the secondary curve. The change characteristics of the segment to be verified within the initial curve are denoted as B1, and the change characteristics of the segment to be verified within the secondary curve are denoted as B2. It is then determined whether B1 and B2 satisfy the condition: (B1-B2)÷B1≥100%. If they satisfy the condition, it indicates that there is an abnormality in the constant current charging process, and a safety abnormality signal is directly generated for display.

4. The method for early warning of safety risks in solid-state energy storage lithium-ion batteries according to claim 3, characterized in that, If B1 and B2 do not satisfy (B1-B2)÷B1≥100%, then the subsequent verification process will be executed.

5. The method for early warning of safety risks in solid-state energy storage lithium-ion batteries according to claim 4, characterized in that, In step three, the specific method for assessing whether the constant voltage charging stage is normal is as follows: During the constant voltage charging phase, it was confirmed that the internal voltage reached U. i The moment when the charging current drops to 0.05C is recorded as the initial moment, and the moment when the charging current drops to 0.05C is recorded as the end moment. The time period between the initial moment and the end moment is recorded as the associated time period. Extract the two sets of partial characteristic curves associated with the two sets of characteristic curves within the associated time period, and extract the voltage and current associated at the same moment from the two sets of partial characteristic curves. Then, use the formula: Change Trend = Voltage ÷ Current to confirm the change trend associated at the corresponding moment. Based on the time direction of the associated time period, generate the trend change curve of the change trend, which is recorded as the undetermined curve. In the curve to be determined, the change characteristics of adjacent points between adjacent time points are determined, and the curve segments with consistent change characteristics are denoted as segments with the same change characteristics. The segments with the same change characteristics associated with each other in the curve to be processed are determined sequentially, and the change characteristics of each segment with the same change characteristics are denoted as Z. q , where q represents different segments of the same change within the curve to be determined; From the identified set of change characteristics Z q Select the maximum value Z q max and minimum value Z q min, identify Z q max and Z q Does min satisfy: (Z) q max-Z q min)÷Z q If the maximum percentage is greater than or equal to 50%, a safety anomaly signal will be generated and displayed directly.

6. The method for early warning of safety risks in solid-state energy storage lithium-ion batteries according to claim 5, characterized in that, If Z q max and Z q min does not satisfy (Z) q max-Z q min)÷Z q If max≥50%, then the confirmed proportional parameter "(Z)" will be used. q max-Z q min)÷Z q The display will show "max".

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