A method for evaluating and warning dynamic air pressure threshold of single battery

Abstract

The application particularly relates to the technical field of battery management, and discloses a kind of single battery dynamic air pressure threshold evaluation and early warning method, the method includes the following steps: according to aging factor, stress contribution and group consistency correction factor, the dynamic air pressure threshold of any one single battery at t time is calculated;The actual air pressure of single battery at t time is collected, and the air pressure deviation index of each battery is calculated according to the actual air pressure and dynamic air pressure threshold;According to the value of air pressure deviation index, trigger different levels of early warning.The application provides a kind of single battery dynamic air pressure threshold evaluation and early warning method, through the actual air pressure of single battery at t time and dynamic air pressure threshold, to establish dynamic, individualized threshold evaluation model, the model can be deployed on the battery management system or cloud platform of energy storage system, to carry out dynamic evaluation and dynamic periodic evaluation to each single battery, to realize early, accurate, interpretable safety early warning to energy storage system.

Description

Technical Field

[0001] This invention relates to the field of battery management technology, specifically to a method for evaluating and warning of dynamic air pressure threshold of a single battery cell. Background Technology

[0002] With the large-scale grid connection of renewable energy and the popularization of electric vehicles, energy storage systems have become a key component of the modern energy system, and the safety of energy storage systems is the primary prerequisite for their large-scale application. Currently, battery management systems mainly assess battery status and perform safety management by monitoring parameters such as battery voltage, temperature, and current; some advanced systems have also introduced monitoring methods such as impedance and stress. In addition, at the battery pack or module level, sensors for smoke, combustible gases, etc., are configured as the last line of defense against thermal runaway.

[0003] In recent years, technological advancements have made it possible to integrate micro-sensors within individual battery cells, particularly built-in temperature and pressure sensors. Internal battery pressure is a sensitive characteristic parameter reflecting the state of electrochemical reactions within the battery. Throughout the battery's lifespan, irreversible gas generation occurs due to electrolyte decomposition, the growth and rupture of the solid electrolyte interfacial film, and the release of lattice oxygen from the cathode material under abusive conditions (such as overcharging and overheating). This leads to a long-term trend of fluctuating and increasing internal pressure. This cumulative increase in pressure directly reflects the decline in battery health and the accumulation of safety risks.

[0004] Current technologies face significant technical bottlenecks when using the internal gas pressure of individual battery cells for safety monitoring. The core issue lies in the fact that current management strategies are too static and isolated, making it difficult to adapt to the dynamic changes throughout the battery's lifespan. Applying traditional fixed-threshold monitoring methods to emerging internal gas pressure parameters creates a fundamental contradiction. Unlike voltage and temperature, which exhibit cyclical characteristics, individual cell gas pressure shows a long-term upward trend with fluctuations. Setting a high fixed threshold to accommodate normal gas pressure at the end of the battery's lifespan would completely eliminate the ability to detect abnormal gas generation events in the early stages of the battery's life.

[0005] Meanwhile, existing technologies generally focus on instantaneous changes in gas pressure, neglecting the valuable information it contains as a cumulative indicator regarding long-term battery health degradation and chronic risk evolution. Furthermore, in large-scale energy storage systems, the inherent inconsistencies among thousands of individual cells mean that current methods lack comprehensive evaluation models that combine historical data from individual cells with the overall state of the battery cluster, making it difficult to accurately identify abnormal cells that act as "weak links." Moreover, many existing early warning models are decoupled from the physicochemical mechanisms of gas generation within the battery, resulting in poor model interpretability, limited generalization ability, and an inability to effectively correlate early warnings with specific failure modes, thus limiting the reliability and practicality of the early warning systems.

[0006] Therefore, there is an urgent need for a method that can fully utilize the gas pressure data of individual battery cells and combine it with information on multiple physical quantities of the battery to establish a dynamic and individualized threshold assessment model in order to solve the above-mentioned technical problems and achieve early, accurate and interpretable safety warnings for energy storage systems. Summary of the Invention

[0007] In view of the above problems, embodiments of the present invention provide a method for evaluating and warning of dynamic air pressure threshold of a single battery cell, which is used to solve the problem that the management strategy of using the internal air pressure of a single battery cell for safety monitoring in the prior art is too static and isolated, and it is difficult to adapt to the dynamic changes throughout the battery's entire life cycle.

[0008] According to an embodiment of the present invention, a method for evaluating and warning of dynamic air pressure threshold of a single battery cell is provided, the method comprising the following steps: According to aging factors Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t ; Collect individual cells The actual air pressure at time t And according to the actual air pressure and dynamic air pressure threshold The pressure deviation index of each battery was calculated. ; According to the air pressure deviation index The value triggers different levels of warnings.

[0009] In one alternative approach, the method based on aging factors... Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t In the steps, the dynamic air pressure threshold The calculation formula is: ; in, For single cell batteries The reference air pressure As an aging factor, For stress contribution, This is a group consistency correction factor.

[0010] In one alternative approach, the method based on aging factors... Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t In the steps, the aging factor The calculation formula is: ; in, For single cell batteries The equivalent number of full-load loops that have already been performed. This is the basic coefficient for gas production rate. This is the aging acceleration index.

[0011] In one alternative approach, the method based on aging factors... Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t In the step, the stress contribution The calculation formula is: ; in, For single cell batteries The energy state at time t γ represents the optimal energy state of a single cell, and γ is the SOE deviation influence coefficient. For single cell batteries The internal absolute temperature at time t The equivalent activation energy for the gas-producing side reaction, Let be the ideal gas constant. It is a pre-exponential factor.

[0012] In one alternative approach, the method based on aging factors... Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t In the step, the stress contribution The calculation formula is: ; in, For single cell batteries The energy state at time t For single cell batteries The internal absolute temperature at time t.

[0013] In one alternative approach, the method based on aging factors... Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t In the step, the group consistency correction factor The calculation formula is: ; in, For single cell batteries The actual air pressure at time t For single cell batteries The average actual gas pressure of all individual cells in the battery pack / cluster at time t. For single cell batteries The standard deviation of the actual gas pressure of all individual cells in the battery pack / cluster at time t. This is the consistency weighting coefficient.

[0014] In one alternative approach, the acquisition of a single battery cell The actual air pressure at time t And according to the actual air pressure and dynamic air pressure threshold The pressure deviation index of each battery was calculated. In the steps, the air pressure deviation index The calculation formula is: ; in, For single cell batteries The actual air pressure at time t For single cell batteries The dynamic air pressure threshold at time t.

[0015] In one alternative approach, the method based on the pressure deviation index... The value triggers different levels of warning steps. When 10% < A Level 1 warning is triggered when the level is ≤20%. When 20% < A level 2 warning is triggered when the concentration is ≤35%. when When the level exceeds 35%, a Level 3 warning is triggered.

[0016] In one alternative approach, the method based on the pressure deviation index... The value triggers different levels of warning steps. When a Level 1 warning is triggered, the battery management system marks the battery as a focus object, highlights it in the operation and maintenance interface, and increases the frequency of its data monitoring. When a Level 2 warning is triggered, the battery management system sends a warning message to the operation and maintenance platform, actively balances or limits the charging and discharging power of the module containing the battery, and prompts staff to conduct an offline inspection. When a Level 3 warning is triggered, the battery management system issues a fault alarm, automatically executes safety policies, and simultaneously activates the fire protection system to notify maintenance personnel for emergency handling.

[0017] In an optional embodiment, the method further includes determining the waiting time for the next evaluation based on the current and maximum air pressure deviation parameters of the battery pack / cluster at time t, according to an evaluation interval determination function; wherein, the calculation formula for the evaluation interval determination function is: ; in, Let t be the number of seconds in the dynamic time interval for the next evaluation calculated at time t. Based on the assessment interval, The current sensitivity coefficient, Let t be the total current of the battery pack / cluster. The rated current of the battery pack / cluster. This is the sensitivity coefficient of the air pressure deviation index. The maximum pressure deviation index of all individual cells in the battery pack / cluster at time t.

[0018] This invention provides a method for assessing and warning of dynamic air pressure thresholds for individual batteries. By using the actual air pressure and dynamic air pressure threshold of an individual battery at time t, a dynamic and individualized threshold assessment model is established. This threshold assessment model can be deployed on the battery management system or cloud platform of the energy storage system to perform dynamic and periodic assessments on each individual battery, thereby achieving early, accurate, and interpretable safety warnings for the energy storage system.

[0019] The length of the evaluation cycle is closely related to the real-time operating status of the battery pack / cluster. Under high-risk conditions such as high-rate charging and discharging of the battery pack / cluster, the energy storage system will automatically shorten the evaluation interval and conduct more frequent monitoring to ensure the overall safety of the system operation.

[0020] The above description is merely an overview of the technical solutions of the embodiments of the present invention. In order to better understand the technical means of the embodiments of the present invention and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0021] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A principle block diagram of the single-cell dynamic air pressure threshold assessment and early warning method provided by the present invention is shown; Figure 2 The flowcharts of the first and second embodiments of the dynamic air pressure threshold assessment and early warning method for single-cell batteries provided by the present invention are shown. Figure 3 The flowchart of the third embodiment of the single-cell dynamic pressure threshold assessment and early warning method provided by the present invention is shown. Detailed Implementation

[0022] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0023] Example 1: Please see the appendix Figure 1 and 2 The method for evaluating and warning the dynamic air pressure threshold of a single battery cell according to an embodiment of the present invention includes the following steps: S110, Based on aging factors Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t Furthermore, dynamic air pressure threshold The calculation formula is: ; in, For single cell batteries The reference pressure, which is calibrated when the battery is put into use or after the first few cycles, represents its initial state pressure. This refers to aging factors, specifically, the cumulative gas production factors caused by battery cycle aging. The stress contribution is the instantaneous gas production caused by the current working stress (temperature and SOE); This is a group consistency correction factor used to adjust the battery size. The influence of stress terms is corrected by comparing it with the average state of the battery pack / cluster in which it is located.

[0024] Furthermore, aging factors The calculation formula is: ; in, For single cell batteries The equivalent number of full charge and discharge cycles that have been completed can be calculated by accumulating the battery management system's ampere-hour integration method or by the change in SOC. Roughly speaking, the number of cycles of the entire battery pack / cluster connected in series can be used as a substitute. This is the basic coefficient for gas production rate, which is related to the battery's chemical system and manufacturing process. For lithium iron phosphate (LFP) batteries, the preferred value is... ; The aging acceleration index is used to characterize the nonlinearity of gas production rate as aging progresses. Preferably, It is 1.05. That is, the aging factor. The preferred calculation formula is: .

[0025] Furthermore, stress contribution The calculation formula is: ; in, For single cell batteries The energy state at time t For the optimal energy state of a single cell, preferably The value is 0.5; γ is the SOE deviation influence coefficient, preferably 1 hPa; For single cell batteries The absolute internal temperature at time t, in Kelvin (K). The recommended optimal value for the equivalent activation energy of the gas-producing side reaction is 35000 J / mol for the electrolyte decomposition of the LFP system. Let be the ideal gas constant, and be . ; The pre-exponential factor is preferably 10. 7 hPa. That is, stress contribution. The preferred calculation formula is: ; in, For single cell batteries The energy state at time t For single cell batteries The internal absolute temperature at time t. The battery management system obtains this information from individual cells. Energy state at time t and single cell battery The internal absolute temperature at time t This allows for the rapid calculation of the instantaneous stress contribution.

[0026] Furthermore, the group consistency correction factor The calculation formula is: ; in, For single cell batteries The actual air pressure at time t can be measured by a pressure sensor. For single cell batteries The average actual gas pressure of all individual cells in the battery pack / cluster at time t. For single cell batteries The standard deviation of the actual gas pressure of all individual cells in the battery pack / cluster at time t; This is the consistency weighting coefficient, preferably 0.2. That is, the group consistency correction factor. The preferred calculation formula is: .

[0027] In summary, the selected aging factors Stress contribution Group Consistency Correction Factor Substituting the calculation formula into the dynamic air pressure threshold The dynamic pressure threshold can be obtained from the calculation formula. The preferred calculation formula is: ; The battery management system obtains data from individual cells. The equivalent number of full-load cycles already experienced Single cell battery Energy state at time t Single cell battery The internal absolute temperature at time t Single cell battery The actual air pressure at time t Single cell battery The average actual gas pressure of all individual cells in the battery pack / cluster at time t. and single cell battery The standard deviation of the actual gas pressure of all individual cells in the battery pack / cluster at time t can be used to calculate the pressure of any individual cell. Dynamic air pressure threshold at time t .

[0028] S120, collecting individual battery cells The actual air pressure at time t And according to the actual air pressure and dynamic air pressure threshold The pressure deviation index of each battery was calculated. ; S130, According to the air pressure deviation index The value triggers different levels of warnings.

[0029] The single-cell dynamic pressure threshold assessment and early warning method of this invention establishes a dynamic and individualized threshold assessment model by using the actual pressure of the single cell at time t and the dynamic pressure threshold. This threshold assessment model can be deployed on the battery management system or cloud platform of the energy storage system to perform dynamic assessment and dynamic periodic assessment of each single cell, so as to achieve early, accurate and interpretable safety warnings for the energy storage system.

[0030] Example 2: Please see the appendix Figure 1 and 2 The single-cell dynamic pressure threshold assessment and early warning method of this invention is the same as that of Embodiment 1, and both include the following steps: S110, Based on aging factors Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t ; S120, collecting individual battery cells The actual air pressure at time t And according to the actual air pressure and dynamic air pressure threshold The pressure deviation index of each battery was calculated. ; S130, According to the air pressure deviation index The value triggers different levels of warnings.

[0031] Furthermore, the air pressure deviation index The calculation formula is: ; in, For single cell batteries The actual air pressure at time t For single cell batteries The dynamic air pressure threshold at time t.

[0032] The battery management system obtains data from individual cells. The actual air pressure at time t and the single cell calculated in Example 1 The pressure deviation index can be calculated from the dynamic pressure threshold at time t. Then, based on the air pressure deviation index... The system compares the data with the preset thresholds of the battery management system, triggering different levels of warnings.

[0033] Furthermore, according to the air pressure deviation index The value triggers different levels of warnings. There are three different levels of warnings in the process. (1) When 10% < When the battery level is ≤20%, a Level 1 warning is triggered, indicating that the battery is experiencing a slight abnormal gas production, which exceeds the expected normal aging and operating condition fluctuations, but does not affect the normal operation of the system. At this time, the battery management system marks the battery as a focus object, highlights it in the operation and maintenance interface, and increases its data monitoring frequency.

[0034] (2) When 20% < When the battery level is ≤35%, a Level 2 warning is triggered, indicating that the battery gas production rate is significantly abnormal and there may be problems such as continuous electrolyte decomposition or SEI film instability, with a moderate safety risk. At this time, the battery management system sends a warning message to the operation and maintenance platform, actively balances the module where the battery is located or limits its charging and discharging power, and prompts staff to conduct offline inspections.

[0035] (3) When When the battery level exceeds 35%, a Level 3 warning is triggered, indicating a severely abnormal rate of gas production in the battery. This strongly suggests the occurrence of dangerous internal reactions such as micro-short circuits, severe electrolyte decomposition, or oxygen evolution at the positive electrode, posing a high risk of thermal runaway. The single-cell dynamic pressure threshold assessment and early warning method of this invention establishes a dynamic and individualized threshold assessment model by using the actual pressure of the single cell at time t and the dynamic pressure threshold. This threshold assessment model can be deployed on the battery management system or cloud platform of the energy storage system to perform dynamic assessment and dynamic periodic assessment of each single cell, so as to achieve early, accurate and interpretable safety warnings for the energy storage system.

[0036] Example 3: Please see the appendix Figure 1 and 3 The single-cell dynamic pressure threshold assessment and early warning method of this invention is the same as that of Embodiment 1, and both include the following steps: S110, Based on aging factors Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t ; S120, collecting individual battery cells The actual air pressure at time t And according to the actual air pressure and dynamic air pressure threshold The pressure deviation index of each battery was calculated. ; S130, According to the air pressure deviation index The value triggers different levels of warnings.

[0037] Furthermore, the method also includes: S140. Based on the current and maximum air pressure deviation parameters of the battery pack / cluster at time t, determine the waiting time for the next evaluation according to the evaluation interval determination function; wherein, the calculation formula of the evaluation interval determination function is: ; in, The dynamic time interval (in seconds) for the next evaluation calculated at time t; The basic evaluation interval, i.e., the evaluation cycle of the battery system in its safest and most idle state, is preferably 600 seconds; The current sensitivity coefficient is used to adjust the effect of the current magnitude on the shortening of the evaluation interval, and is preferably 6; Let t be the total current of the battery pack / cluster. The rated current of the battery pack / cluster depends on the specific scenario; The pressure deviation index sensitivity coefficient is used to adjust the effect of the degree of individual anomaly on the shortening of the assessment interval, and is preferably 10; Let be the maximum pressure deviation index of all individual cells in the battery pack / cluster at time t. That is, the preferred formula for calculating the evaluation interval determination function is: .

[0038] When the energy storage system operates at high current, or when any single cell produces abnormal gas leading to an increase in its gas pressure deviation index, the corresponding risk term in the denominator will increase, thereby nonlinearly shortening the overall assessment interval; this not only enables automatic and encrypted monitoring of single cells that issue warnings, but also takes into account the operational risks of the entire battery pack / cluster.

[0039] The single-cell dynamic pressure threshold assessment and early warning method of this invention establishes a dynamic and individualized threshold assessment model by using the actual pressure and dynamic pressure threshold of a single cell at time t. This threshold assessment model can be deployed on the battery management system or cloud platform of the energy storage system to perform dynamic and periodic assessments on each single cell, thereby achieving early, accurate, and interpretable safety warnings for the energy storage system. Furthermore, the length of the assessment cycle is closely related to the real-time operating status of the battery pack / cluster. Under high-risk conditions such as high-rate charging and discharging of the battery pack / cluster, the energy storage system will automatically shorten the assessment interval and perform more frequent monitoring to ensure the overall safety of the system operation.

[0040] The technical benefits of this invention are primarily reflected in the fundamental improvement of early warning capabilities. By generating "tailor-made" health thresholds for each battery, it achieves a leap from "static" to "dynamic" monitoring, greatly improving the accuracy of early warnings. More importantly, by directly monitoring pressure parameters strongly correlated with irreversible side reactions within the battery and combining this with a threshold assessment model, the method of this invention can advance the early warning time to weeks or even months before catastrophic events such as thermal runaway, significantly improving the early warning capability. Furthermore, the various components of the threshold assessment model make the early warning results highly interpretable, helping maintenance personnel understand the root cause of the fault.

[0041] Based on this, the method of the present invention combines "individual" and "group" by introducing a group consistency correction factor. It not only evaluates the "absolute" state of the battery, but also its "relative" state, making the energy storage system exceptionally sensitive to "short-board" batteries that show inconsistencies in the early stages. This ability to accurately locate specific abnormal cells enables maintenance personnel to perform precise maintenance, thereby significantly improving maintenance efficiency and ultimately reducing the total life cycle cost of the energy storage system.

[0042] Finally, the method of the present invention achieves intelligent scheduling of monitoring resources by introducing a dynamic evaluation interval function related to real-time current. The energy storage system can encrypt monitoring when the battery is under high load and high risk, and reduce the frequency when idle. Thus, under the premise of ensuring safety, the computing load of the cloud platform or EMS is effectively reduced, and the overall operating efficiency of the system is improved.

[0043] The algorithms or displays provided herein are not inherently related to any particular computer, virtual system, or other device. Furthermore, the embodiments of this invention are not directed to any particular programming language.

[0044] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. Similarly, for the sake of brevity and to aid in understanding one or more aspects of the invention, in the description of exemplary embodiments of the invention above, various features of the embodiments are sometimes grouped together in a single embodiment, figure, or description thereof. The claims, which follow the detailed description, are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.

[0045] Those skilled in the art will understand that the modules in the device of the embodiment can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiment can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components, except that at least some of such features and / or processes or units are mutually exclusive.

[0046] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be construed as limiting the order of execution.

Claims

1. A method for assessing and issuing early warning of dynamic gas pressure threshold for a single battery cell, characterized in that, The method includes the following steps: According to aging factors Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t ; Collect individual cells The actual air pressure at time t And according to the actual air pressure and dynamic air pressure threshold The pressure deviation index of each battery was calculated. ; According to the air pressure deviation index The value triggers different levels of warnings; According to aging factors Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t In the steps, the dynamic air pressure threshold The calculation formula is: ； in, For single cell batteries The reference air pressure, As an aging factor, For stress contribution, This is a group consistency correction factor.

2. The method according to claim 1, characterized in that, According to aging factors Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t In the steps, the aging factor The calculation formula is: ； in, For single cell batteries The equivalent number of full-load loops that have already been performed. This is the basic coefficient for gas production rate. It is an aging acceleration index.

3. The method according to claim 1, characterized in that, According to aging factors Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t In the step, the stress contribution The calculation formula is: ； in, For single cell batteries The energy state at time t γ represents the optimal energy state of a single cell, and γ is the SOE deviation influence coefficient. For single cell batteries The internal absolute temperature at time t The equivalent activation energy for the gas-producing side reaction, Let be the ideal gas constant. It is a pre-exponential factor.

4. The method according to claim 3, characterized in that, According to aging factors Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t In the step, the stress contribution The calculation formula is: ； in, For single cell batteries The energy state at time t For single cell batteries The internal absolute temperature at time t.

5. The method according to claim 1, characterized in that, According to aging factors Stress contribution Group Consistency Correction Factor Calculate any single cell Dynamic air pressure threshold at time t In the step, the group consistency correction factor The calculation formula is: ； in, For single cell batteries The actual air pressure at time t For single cell batteries The average actual gas pressure of all individual cells in the battery pack / cluster at time t. For single cell batteries The standard deviation of the actual gas pressure of all individual cells in the battery pack / cluster at time t. This is the consistency weighting coefficient.

6. The method according to claim 1, characterized in that, The collected single battery The actual air pressure at time t And according to the actual air pressure and dynamic air pressure threshold The pressure deviation index of each battery was calculated. In the steps, the air pressure deviation index The calculation formula is: ； in, For single cell batteries The actual air pressure at time t For single cell batteries The dynamic air pressure threshold at time t.

7. The method according to claim 1, characterized in that, According to the air pressure deviation index The value triggers different levels of warning steps. When 10% < A Level 1 warning is triggered when the level is ≤20%. When 20% < A level 2 warning is triggered when the concentration is ≤35%. when When the level exceeds 35%, a Level 3 warning is triggered.

8. The method according to claim 7, characterized in that, According to the air pressure deviation index The value triggers different levels of warning steps. When a Level 1 warning is triggered, the battery management system marks the battery as a focus object, highlights it in the operation and maintenance interface, and increases the frequency of its data monitoring. When a Level 2 warning is triggered, the battery management system sends a warning message to the operation and maintenance platform, actively balances or limits the charging and discharging power of the module containing the battery, and prompts staff to conduct an offline inspection. When a Level 3 warning is triggered, the battery management system issues a fault alarm, automatically executes safety policies, and simultaneously activates the fire protection system to notify maintenance personnel for emergency handling.

9. The method according to claim 1, characterized in that, It also includes determining the waiting time for the next evaluation based on the current and maximum air pressure deviation parameters of the battery pack / cluster at time t, according to the evaluation interval determination function; wherein, the calculation formula of the evaluation interval determination function is: ； in, Let t be the number of seconds in the dynamic time interval for the next evaluation calculated at time t. Based on the assessment interval, The current sensitivity coefficient is... Let t be the total current of the battery pack / cluster. The rated current of the battery pack / cluster. The sensitivity coefficient of the air pressure deviation index. The maximum pressure deviation index of all individual cells in the battery pack / cluster at time t.

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