A thermal runaway diffusion test method and system for energy storage batteries

Abstract

The present invention discloses a thermal runaway diffusion test method and system for an energy storage battery, relates to the technical field of thermal runaway testing, and solves the technical problem in the prior art that the leakage trend of diffusion gas cannot be predicted after thermal runaway occurs. Specifically, thermal runaway diffusion analysis and evaluation is performed. After completing the internal energy monitoring of the energy storage battery, if the internal energy thermal disturbance monitoring of the energy storage battery is abnormal and the control effect is poor, the thermal runaway diffusion analysis and evaluation is performed on the energy storage battery, and the thermal runaway diffusion of the energy storage battery is analyzed and evaluated based on data collection and analysis; diffusion trend monitoring is performed after the thermal runaway phenomenon occurs in the energy storage battery, and the gas leakage trend generated by the real-time thermal runaway is analyzed in combination with the location of the leakage point; source tracing control is performed through thermal runaway diffusion trend prediction monitoring and protection, and after completion, the energy storage battery is traced and monitored.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal runaway testing, and in particular to a thermal runaway diffusion testing method and system for an energy storage battery. Background Art

[0002] Battery thermal runaway refers to the uncontrolled acceleration of the internal chemical reaction of the battery under certain specific conditions, resulting in sharp changes in battery temperature, current and other parameters; thermal runaway diffusion refers to the process in which, when a battery cell in a battery pack or battery module experiences thermal runaway, heat, gas, flame, etc. are transferred to adjacent battery cells in some way, causing them to also experience thermal runaway one after another. This is a chain reaction that will continuously expand the scope of battery system failures.

[0003] However, in the prior art, it is not possible to monitor the energy thermal disturbance inside the energy storage battery, and it is not possible to infer the thermal control diffusion risk based on the thermal disturbance monitoring, and it is impossible to provide targeted protection. In addition, it is not possible to predict the leakage trend of the diffusion gas when thermal runaway occurs, which reduces the efficiency of thermal runaway protection.

[0004] In view of the above technical defects, a solution is now proposed. Summary of the invention

[0005] The purpose of the present invention is to solve the above-mentioned problems and to provide a thermal runaway diffusion testing method and system for energy storage batteries.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A thermal runaway diffusion test method for an energy storage battery, the test method steps are as follows:

[0008] Internal energy monitoring: monitor the energy inside the energy storage battery, and analyze and infer the current energy state inside the battery based on the operation process of the energy storage battery, so as to monitor in real time whether there is energy thermal disturbance;

[0009] Thermal runaway diffusion analysis and evaluation: after completing the internal energy monitoring of the energy storage battery, if the internal energy thermal disturbance monitoring of the energy storage battery is abnormal and the control effect is poor, the thermal runaway diffusion analysis and evaluation of the energy storage battery is carried out. The thermal runaway diffusion of the energy storage battery is analyzed and evaluated based on the data collection and analysis;

[0010] Diffusion trend monitoring: after the energy storage battery has thermal runaway, the gas leakage trend generated by the real-time thermal runaway is analyzed in combination with the location of the leakage point;

[0011] Traceability control, through prediction, monitoring and protection of thermal runaway diffusion trend, and traceability monitoring of energy storage batteries after completion.

[0012] As a preferred embodiment of the present invention, the internal energy monitoring process is as follows:

[0013] Collect internal energy information and substitute it into the formula to obtain the internal energy monitoring coefficient. If the internal energy monitoring coefficient exceeds the internal energy monitoring coefficient threshold, generate an energy abnormality signal and proceed to the next step; if the internal energy monitoring coefficient of the battery cell does not exceed the internal energy monitoring coefficient threshold during the operation stage of the energy storage battery, generate an energy normal signal.

[0014] As a preferred embodiment of the present invention, the formula is:

[0015] , where J is the internal energy monitoring coefficient, fqu1, fqu2 and fqu3 are preset proportional coefficients, and α is used as an error correction factor. When the energy storage battery is operating at rated power supply, the value is 1.4, and when the energy storage battery is operating at over-rated power supply, the value is 0.9.

[0016] As a preferred embodiment of the present invention, the internal energy information includes the continuously increasing span of the accumulated heat released by the chemical reaction inside the battery cell during the operation stage of the energy storage battery and the corresponding excess amount of heat dissipated from the battery cell, the corresponding span value ratio of the increase span value of the heat released by the exothermic reaction inside the battery cell and the reaction speed increase span of the endothermic reaction, and the continuously increasing frequency of the ratio of the number of exothermic reactions to the number of endothermic reactions when the heat released by the exothermic reaction inside the current battery cell of the energy storage battery increases.

[0017] As a preferred embodiment of the present invention, the thermal runaway diffusion analysis and evaluation process is as follows:

[0018] Collect supply performance information and controllable performance information. If the supply performance information does not exceed the percentage decrease span threshold, and the controllable performance information does not exceed the energy increase span threshold, a low thermal impact signal is generated; if the supply performance information exceeds the percentage decrease span threshold, or the controllable performance information exceeds the energy increase span threshold, a high thermal impact signal is generated; at the same time, analyze and predict the spread of thermal runaway;

[0019] The supply performance information and controllable performance information are respectively the decrease span corresponding to the average value of the real-time supply of the energy storage battery controlled by the battery cell and the proportion of the supply demand in the current stage, and the increase span value of the non-decaying energy inside the battery cell during the non-overlapping period of the energy decay period and the energy increase period inside the battery cell.

[0020] As a preferred embodiment of the present invention, the temperature rise gradient parameter and the mechanical loss parameter are collected. If the temperature rise gradient parameter exceeds the temperature gradient span threshold, or the mechanical loss parameter exceeds the loss span threshold, a heat diffusion signal is generated; if the temperature rise gradient parameter does not exceed the temperature gradient span threshold, and the mechanical loss parameter does not exceed the loss span threshold, a non-diffusion signal is generated;

[0021] The temperature rise gradient parameter and mechanical loss parameter are respectively the expansion span of the temperature gradient in the thickness direction of the battery after thermal runaway occurs inside the energy storage battery, and the increase span of the mechanical loss amount exceeding the loss mean at any position on the internal surface of the battery under the current thermal environment of the energy storage battery.

[0022] As a preferred embodiment of the present invention, the diffusion trend monitoring process is as follows:

[0023] Get the diffusion point, complete the trajectory prediction, analyze the location of the diffusion point, if the location corresponds to the direction of gas diffusion is the gravity direction, then mark it as the gravity direction, if the location corresponds to the direction of gas diffusion is the non-gravity direction, then mark it as the anti-gravity direction;

[0024] When the diffusion direction is toward the gravity direction, the diffusion velocity of the diffusion gas in the diffusion direction is obtained and the diffusion direction is used as the horizontal line. The descending velocity and ascending velocity of the high-density gas and the low-density gas are obtained according to the gas density, and the descending gas arc and the ascending gas arc of the gas diffusion are obtained according to the velocity value, and the arc direction is used as the diffusion protection direction. At the same time, according to the flammability of the corresponding density gas, the descending gas arc or the ascending gas arc is set as the flame injection direction, and the flame injection direction is protected.

[0025] As a preferred embodiment of the present invention, when the diffusion direction is the anti-gravity direction, a gas arc is obtained. If the gas arc in the anti-gravity direction corresponds to a high-density gas which is a combustible gas, the administrator protects the area according to the corresponding gas type; if the gas arc in the anti-gravity direction corresponds to a low-density gas which is a combustible gas, the administrator performs flame spray protection according to the characteristics of the leaked diffusion gas.

[0026] As a preferred embodiment of the present invention, the traceability control process is as follows:

[0027] Collect the proportion coefficient and speed coefficient. If the proportion coefficient exceeds the number proportion threshold and the speed coefficient does not exceed the speed proportion threshold, a priority control signal is generated; if the proportion coefficient does not exceed the number proportion threshold, or the speed coefficient exceeds the speed proportion threshold, a priority protection signal is generated;

[0028] The proportion coefficient is the ratio of the proportion of the number of completed heat release controls to the total number of controls and the corresponding numerical ratio of the number of non-first heat release controls in the current number of abnormal risk reactants;

[0029] The speed coefficient is the numerical ratio of the speed of shortening the interval time of diffusion after the risk reactant thermal runaway occurs to the speed of increasing the duration of expansion.

[0030] A thermal runaway diffusion test system for an energy storage battery comprises a server, wherein the server is communicatively connected to an internal energy monitoring unit, a thermal runaway diffusion analysis unit, a diffusion trend monitoring unit and a traceability control unit;

[0031] The internal energy monitoring unit is used to monitor the energy inside the energy storage battery, and analyze and infer the current energy state inside the battery according to the operation process of the energy storage battery, so as to monitor in real time whether there is energy thermal disturbance;

[0032] The thermal runaway diffusion analysis unit is used to complete the internal energy monitoring of the energy storage battery. If the internal energy thermal disturbance monitoring of the energy storage battery is abnormal and the control effect is poor, the thermal runaway diffusion analysis and evaluation of the energy storage battery is performed. The thermal runaway diffusion of the energy storage battery is analyzed and evaluated based on data collection and analysis;

[0033] Diffusion trend monitoring unit, used to analyze the gas leakage trend generated by real-time thermal runaway and the location of the leakage point after the thermal runaway of the energy storage battery occurs;

[0034] The traceability control unit is used to predict, monitor and protect against thermal runaway diffusion trends, and perform traceability monitoring of energy storage batteries after completion.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] 1. In the present invention, energy is monitored inside the energy storage battery, and the energy state inside the current battery is inferred according to the operation process of the energy storage battery, so as to monitor in real time whether there is energy thermal disturbance, so as to timely warn of thermal runaway. At the same time, the energy state of the energy storage battery can be monitored in real time, and the battery charging and discharging can be controlled more reasonably, which promotes the operation efficiency of the energy storage battery and improves the safety of the use of the energy storage battery;

[0037] After completing the internal energy monitoring of the energy storage battery, if the internal energy thermal disturbance monitoring of the energy storage battery is abnormal and the control effect is poor, the thermal runaway diffusion analysis and evaluation of the energy storage battery is carried out. The thermal runaway diffusion of the energy storage battery is analyzed and evaluated based on the data collection and analysis. The degree of impact of the thermal runaway diffusion is accurately judged according to the real-time energy status of the energy storage battery, which is convenient for prior targeted protection, reducing the damage of thermal runaway to the energy storage battery and reducing the supply impact of the energy storage battery on the power consumption end.

[0038] 2. In the present invention, after the thermal runaway phenomenon occurs in the energy storage battery, the gas leakage trend generated by the real-time thermal runaway is analyzed in combination with the location of the leakage point, the development trend of the thermal runaway diffusion of the energy storage battery is inferred, and the leakage trajectory is reasonably predicted, so as to facilitate targeted protection and timely protection in the direction of the leakage trajectory when the thermal runaway cannot be controlled, thereby reducing the impact of the thermal runaway diffusion inside the energy storage battery;

[0039] Through the prediction, monitoring and protection of thermal runaway diffusion trends, and after completion, traceability monitoring of energy storage batteries can be carried out to infer the cause of thermal runaway diffusion in the current energy storage battery, that is, the reactants of the chemical reaction that causes energy thermal runaway, so that targeted monitoring can be carried out in the energy storage battery and operating environment, and the impact of thermal runaway diffusion can be accurately avoided and reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0041] Figure 1 This is a flow chart of a method according to Embodiment 1 of the present invention;

[0042] Figure 2 This is a principle block diagram of the second embodiment of the present invention. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0045] Embodiment 1

[0046] See also Figure 1 As shown, a thermal runaway diffusion test method for energy storage batteries, the specific thermal runaway diffusion test method steps are as follows:

[0047] Internal energy monitoring: Energy monitoring inside the energy storage battery. According to the operation process of the energy storage battery, the energy state inside the battery can be analyzed and inferred, so as to monitor in real time whether there is energy thermal disturbance, so as to give early warning of thermal runaway in time. At the same time, the energy state of the energy storage battery can be monitored in real time, and the battery charging and discharging can be controlled more reasonably, which can promote the operation efficiency of the energy storage battery and improve the safety of the use of the energy storage battery.

[0048] Thermal runaway diffusion analysis and evaluation: After completing the internal energy monitoring of the energy storage battery, if the internal energy thermal disturbance monitoring of the energy storage battery is abnormal and the control effect is poor, the thermal runaway diffusion analysis and evaluation of the energy storage battery is carried out. The thermal runaway diffusion of the energy storage battery is analyzed and evaluated based on the data collection and analysis. The degree of influence of the thermal runaway diffusion is accurately judged according to the real-time energy state of the energy storage battery, which is convenient for targeted protection in advance, reducing the damage of thermal runaway to the energy storage battery and reducing the supply impact of the energy storage battery on the power consumption end;

[0049] Diffusion trend monitoring: after the energy storage battery has thermal runaway, the gas leakage trend generated by the real-time thermal runaway is analyzed in combination with the location of the leakage point to infer the development trend of the thermal runaway diffusion of the energy storage battery and make a reasonable prediction of the leakage trajectory, so as to facilitate targeted protection and timely protection in the direction of the leakage trajectory when thermal runaway cannot be controlled, thereby reducing the impact of thermal runaway diffusion inside the energy storage battery;

[0050] Source tracing control: through prediction, monitoring and protection of thermal runaway diffusion trend, and after completion, source tracing monitoring of energy storage batteries can be carried out to infer the cause of thermal runaway diffusion in the current energy storage battery, that is, the reactants of the chemical reaction that causes energy thermal runaway, so that targeted monitoring can be carried out in the energy storage battery and operating environment, and the impact of thermal runaway diffusion can be accurately avoided and reduced;

[0051] The internal energy monitoring process is as follows:

[0052] Obtain the continuous increase span of the accumulated heat released by the chemical reaction inside the battery cell during the operation stage of the energy storage battery and the corresponding excess amount of heat dissipated from the battery cell, and mark the continuous increase span of the accumulated heat released by the chemical reaction inside the battery cell during the operation stage of the energy storage battery and the corresponding excess amount of heat dissipated from the battery cell as KDZ;

[0053] In the rising stage of the accumulated heat release of the chemical reaction inside the battery cell, the numerical ratio of the increase span value of the heat release of the exothermic reaction inside the battery cell to the corresponding span value of the increase span of the reaction speed of the endothermic reaction is collected, where the numerical ratio only counts the numerical fluctuations of the two data, and does not consider the influence of the inconsistent units of the two data. In addition, in the chemical reaction, the exothermic reaction will cause heat release and the increase in heat release will promote the endothermic reaction. Similarly, when the heat release continues to increase, the corresponding numerical ratio still increases, indicating that the current heat release effect far exceeds the heat absorption effect of the endothermic reaction, and the numerical ratio of the increase span value of the heat release of the exothermic reaction inside the battery cell to the corresponding span value of the increase span of the reaction speed of the endothermic reaction is marked as KDB;

[0054] Obtain the continuous increase frequency of the ratio of the number of exothermic reactions to the number of endothermic reactions when the heat released by the exothermic reaction inside the current battery cell of the energy storage battery increases, and mark the continuous increase frequency of the ratio of the number of exothermic reactions to the number of endothermic reactions when the heat released by the exothermic reaction inside the current battery cell of the energy storage battery increases as CPL;

[0055] The above collected information is uniformly marked as internal energy information, and substituted into the formula to obtain the internal energy monitoring coefficient of the battery cell during the operation stage of the energy storage battery, where the formula is:

[0056] , where J is the internal energy monitoring coefficient, fqu1, fqu2 and fqu3 are preset proportional coefficients, and α is used as an error correction factor. When the energy storage battery is operated at rated power supply, the value is 1.4, and when the energy storage battery is operated at over-rated power supply, the value is 0.9;

[0057] Compare the internal energy monitoring coefficient of the battery cell during the operation phase of the energy storage battery with the internal energy monitoring coefficient threshold:

[0058] If the internal energy monitoring coefficient of the battery cell during the operation phase of the energy storage battery exceeds the internal energy monitoring coefficient threshold, it is inferred that the internal energy monitoring during the operation phase of the energy storage battery is abnormal, an energy abnormality signal is generated and sent to the administrator terminal, and the administrator controls the system to proceed to the next step;

[0059] If the internal energy monitoring coefficient of the battery cell during the operation phase of the energy storage battery does not exceed the internal energy monitoring coefficient threshold, it is inferred that the internal energy monitoring during the operation phase of the energy storage battery is normal, and an energy normal signal is generated and sent to the administrator terminal;

[0060] The thermal runaway diffusion analysis and evaluation process is as follows:

[0061] During the energy storage battery energy abnormality stage, the corresponding decrease span of the average value of the real-time supply of the energy storage battery controlled by the battery cell and the proportion of the supply demand in the current stage is obtained. At the same time, during the energy storage battery energy abnormality stage, the internal non-decay energy increase span value of the battery cell in the non-overlapping period of the energy decay period and the energy increase period is obtained, and the corresponding decrease span of the average value of the real-time supply of the energy storage battery controlled by the battery cell and the proportion of the supply demand in the current stage, and the internal non-decay energy increase span value of the battery cell in the non-overlapping period of the energy decay period and the energy increase period are marked as supply performance information and controllable performance information, respectively, and compared with the proportion decrease span threshold and energy increase span threshold respectively:

[0062] If the corresponding decrease span of the average value of the real-time supply of the cell-controlled energy storage battery and the proportion of the supply demand in the current stage does not exceed the proportion decrease span threshold, and the increase span value of the non-decaying energy inside the cell in the non-overlapping period of the energy decay period and the energy increase period does not exceed the energy increase span threshold, it is inferred that the risk of thermal runaway of the energy of the cell inside the energy storage battery is low, and a low thermal impact signal is generated and sent to the administrator terminal;

[0063] If the corresponding decrease span of the average value of the real-time supply of the cell-controlled energy storage battery and the proportion of the supply demand in the current stage exceeds the proportion decrease span threshold, or the non-decay energy increase span value inside the cell during the non-overlapping period of the energy decay period and the energy increase period inside the cell exceeds the energy increase span threshold, it is inferred that the energy thermal runaway risk of the cell inside the energy storage battery is high, and a high thermal impact signal is generated and sent to the administrator terminal. After receiving the low thermal impact signal, the administrator terminal controls the supply task of the energy storage battery, debugs the performance of the internal components of the energy storage battery, and executes the previous step after the rectification is completed; at the same time, the thermal runaway diffusion is analyzed and predicted:

[0064] After thermal runaway occurs inside the energy storage battery, the temperature gradient in the direction of the battery thickness is expanded, and at the same time, the mechanical loss amount rising span exceeding the loss mean at any position on the internal surface of the battery under the current thermal environment of the energy storage battery is obtained. The temperature gradient in the direction of the battery thickness is expanded after thermal runaway occurs inside the energy storage battery, and the mechanical loss amount rising span exceeding the loss mean at any position on the internal surface of the battery under the current thermal environment of the energy storage battery are marked as temperature rise gradient parameters and mechanical loss parameters, respectively. The mechanical loss is represented by the wear amount of each material layer inside the battery under the current thermal environment, which is reflected by the thickness or the amount of depression at any position, and the thermal environment is represented by the current heat release environment inside the battery; and they are compared with the temperature gradient span threshold and the loss span threshold respectively:

[0065] If thermal runaway occurs inside the energy storage battery and the temperature gradient in the battery thickness direction expands beyond the temperature gradient span threshold, or the mechanical loss at any position on the internal surface of the battery in the current thermal environment exceeds the loss span threshold, it is inferred that thermal runaway diffusion has occurred in the current energy storage battery, and a thermal diffusion signal is generated and sent to the administrator terminal. After receiving the thermal diffusion signal, the administrator terminal terminates the task of the current energy storage battery and stops all energy transmission, and proceeds to the next step;

[0066] If the expansion span of the temperature gradient in the thickness direction of the battery after thermal runaway occurs inside the energy storage battery does not exceed the temperature gradient span threshold, and the increase span of the mechanical loss amount at any position on the internal surface of the battery under the current thermal environment of the energy storage battery does not exceed the loss span threshold, it is inferred that the current energy storage battery has not experienced thermal runaway diffusion, and a non-diffusion signal is generated and sent to the administrator terminal. The administrator terminal records the cause of the current thermal runaway and performs maintenance on the energy storage battery;

[0067] The diffusion trend monitoring process is as follows:

[0068] The diffusion point of the energy storage battery is obtained through the thermal diffusion monitoring in the previous step, and the diffusion trend of the gas release at the diffusion point is monitored to complete the trajectory prediction, and the location of the diffusion point in the energy storage battery is analyzed. If the gas diffusion direction corresponding to the location is the gravity direction, it is marked as the gravity direction. If the gas diffusion direction corresponding to the location is the non-gravity direction, it is marked as the anti-gravity direction, where the anti-gravity direction is represented by the current gas diffusion direction except the direction perpendicular to the horizontal line upward; the gravity direction is represented by the current gas diffusion direction not being the direction perpendicular to the horizontal line upward; in the actual monitoring process in this application, precise division will be made according to the angle, specifically, the fan-shaped range of forty-five degrees to the left and right of the vertical line is set as the anti-gravity direction, and the direction in the remaining area is the gravity direction, which mainly reflects the effect of gravity on gas diffusion;

[0069] When the diffusion direction is toward the gravity direction, the leaked diffusion gas is divided into high-density gas and low-density gas according to the type of gas, and the diffusion speed of the diffusion gas in the diffusion direction is obtained at the same time, and the diffusion direction is used as the horizontal line. The descending speed and ascending speed of the high-density gas and the low-density gas are obtained according to the gas density, and the descending gas arc and the ascending gas arc of the gas diffusion are obtained according to the speed value, and the arc direction is used as the diffusion protection direction. At the same time, according to the flammability of the corresponding density gas, the descending gas arc or the ascending gas arc is set as the flame injection direction, and the flame injection direction is protected;

[0070] When the diffusion direction is the anti-gravity direction, the gas arc is obtained according to the type of leaked diffusion gas, and the gas arc is analyzed. If the gas arc in the anti-gravity direction corresponds to a high-density gas that is a combustible gas, it is inferred that the flame spray distance of the current leaking gas arc is low but the flame range is wide, and the administrator protects the area according to the corresponding gas type; if the gas arc in the anti-gravity direction corresponds to a low-density gas that is a combustible gas, it is inferred that the flame spray distance of the current leaking gas arc is long, but as the flame continues to spray, the flame in the area where the diffusion point is located will continue to decrease, and the administrator performs flame spray protection according to the characteristics of the leaking diffusion gas;

[0071] According to different diffusion directions and different gas types, when no flame is generated, the concentration is controlled according to the gas leakage trajectory, and the combustible gas is given priority concentration control;

[0072] The traceability control process is as follows:

[0073] After completing the diffusion trend monitoring and diffusion control, the thermal runaway diffusion of the energy storage battery is traced and controlled. According to the thermal runaway diffusion monitoring process of the energy storage battery, the cause of the thermal runaway is collected, and the reactants of the chemical reaction of the thermal runaway cause are marked as risk reactants. When the real-time release amount of the risk reactant increases abnormally, the proportion of the number of heat release controls completed by the risk reactant to the total control number is collected, and the proportion of the number of non-first heat release controls in the current abnormal number of risk reactants is obtained, and the proportion coefficient is calculated based on the ratio of the two proportions;

[0074] At the same time, according to the diffusion monitoring after thermal runaway, the speed of shortening the interval time and increasing speed of the duration of expansion of the risk reactant after thermal runaway are collected, and the speed coefficient is calculated according to the ratio, and the proportion coefficient and speed coefficient are compared with the number proportion threshold and speed proportion threshold respectively:

[0075] If the proportion coefficient exceeds the frequency proportion threshold, and the speed coefficient does not exceed the speed proportion threshold, it is inferred that the control efficiency is high when the current risk reactant is abnormal, and a priority control signal is generated and sent to the administrator terminal together with the risk reactant;

[0076] If the proportion coefficient does not exceed the frequency proportion threshold, or the speed coefficient exceeds the speed proportion threshold, it is inferred that the control efficiency is low when the current risk reactant is abnormal, and a priority protection signal is generated and sent to the administrator terminal together with the risk reactant; the administrator performs targeted control according to the type of reactant, performs thermal runaway control on the risk reactant of the priority control signal and increases the control time, and conversely, performs diffusion protection preparation when the thermal runaway control efficiency of the risk reactant of the priority control signal is low;

[0077] Embodiment 2

[0078] See also Figure 2 As shown, a thermal runaway diffusion test system for an energy storage battery includes a server, and the server is communicatively connected to an internal energy monitoring unit, a thermal runaway diffusion analysis unit, a diffusion trend monitoring unit, and a traceability control unit;

[0079] The internal energy monitoring unit is used to monitor the energy inside the energy storage battery, and analyze and infer the current energy state inside the battery according to the operation process of the energy storage battery, so as to monitor in real time whether there is energy thermal disturbance;

[0080] The thermal runaway diffusion analysis unit is used to complete the internal energy monitoring of the energy storage battery. If the internal energy thermal disturbance monitoring of the energy storage battery is abnormal and the control effect is poor, the thermal runaway diffusion analysis and evaluation of the energy storage battery is performed. The thermal runaway diffusion of the energy storage battery is analyzed and evaluated based on data collection and analysis;

[0081] Diffusion trend monitoring unit, used to analyze the gas leakage trend generated by real-time thermal runaway and the location of the leakage point after the thermal runaway of the energy storage battery occurs;

[0082] The traceability control unit is used to predict, monitor and protect against thermal runaway diffusion trends, and perform traceability monitoring of energy storage batteries after completion.

[0083] The above formulas are obtained by collecting a large amount of data and performing software simulation, and a formula close to the actual value is selected. The coefficients in the formula are set by technicians in this field according to actual conditions;

[0084] When the present invention is in use, internal energy monitoring is performed to monitor the energy inside the energy storage battery, and the current energy state inside the battery is inferred based on the analysis of the operation process of the energy storage battery, so as to facilitate real-time monitoring of whether there is energy thermal disturbance; thermal runaway diffusion analysis and evaluation is performed to the energy storage battery after the internal energy monitoring of the energy storage battery is completed, if the internal energy thermal disturbance monitoring of the energy storage battery is abnormal and the control effect is poor, and the thermal runaway diffusion of the energy storage battery is analyzed and evaluated based on data collection and analysis; diffusion trend monitoring is performed after the energy storage battery has thermal runaway phenomenon, and the gas leakage trend generated by the real-time thermal runaway is analyzed in combination with the location of the leakage point; source tracing control is performed through thermal runaway diffusion trend prediction monitoring and protection, and after completion, the energy storage battery is traced and monitored.

[0085] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A thermal runaway diffusion test method for energy storage batteries, characterized in that: The test method steps are as follows: Internal energy monitoring: monitor the energy inside the energy storage battery, and analyze and infer the current energy state inside the battery based on the operation process of the energy storage battery, so as to monitor in real time whether there is energy thermal disturbance; Thermal runaway diffusion analysis and evaluation: after completing the internal energy monitoring of the energy storage battery, if the internal energy thermal disturbance monitoring of the energy storage battery is abnormal and the control effect is poor, the thermal runaway diffusion analysis and evaluation of the energy storage battery is carried out. The thermal runaway diffusion of the energy storage battery is analyzed and evaluated based on the data collection and analysis; Diffusion trend monitoring: After the energy storage battery has thermal runaway, the gas leakage trend generated by the real-time thermal runaway is analyzed in combination with the location of the leakage point; the diffusion trend monitoring process is as follows: Get the diffusion point, complete the trajectory prediction, analyze the location of the diffusion point, if the location corresponds to the direction of gas diffusion is the gravity direction, then mark it as the gravity direction, if the location corresponds to the direction of gas diffusion is the non-gravity direction, then mark it as the anti-gravity direction; When the diffusion direction is toward the gravity direction, the diffusion velocity of the diffusion gas in the diffusion direction is obtained and the diffusion direction is used as the horizontal line. The descending velocity and ascending velocity of the high-density gas and the low-density gas are obtained according to the gas density, and the descending gas arc and the ascending gas arc of the gas diffusion are obtained according to the velocity value, and the arc direction is used as the diffusion protection direction. At the same time, according to the flammability of the corresponding density gas, the descending gas arc or the ascending gas arc is set as the flame injection direction, and the flame injection direction is protected; Traceability control, through thermal runaway diffusion trend monitoring and protection, and traceability monitoring of energy storage batteries after completion.

2. A thermal runaway diffusion test method for an energy storage battery according to claim 1, characterized in that: The internal energy monitoring process is as follows: Collect internal energy information and substitute it into the formula to obtain the internal energy monitoring coefficient. If the internal energy monitoring coefficient exceeds the internal energy monitoring coefficient threshold, generate an energy abnormality signal and proceed to the next step; if the internal energy monitoring coefficient of the battery cell does not exceed the internal energy monitoring coefficient threshold during the operation stage of the energy storage battery, generate an energy normal signal.

3. A thermal runaway diffusion test method for an energy storage battery according to claim 2, characterized in that: The formula is: , where J is the internal energy monitoring coefficient, fqu1, fqu2 and fqu3 are respectively the preset proportional coefficients, and α is used as the error correction factor. When the energy storage battery is operating at rated power supply, the value is 1.4, and when the energy storage battery is operating at over-rated power supply, the value is 0.9; the internal energy information includes the continuous increase span of the accumulated heat release of the chemical reaction inside the battery cell during the operation stage of the energy storage battery and the corresponding excess amount of heat dissipated from the battery cell, the ratio of the increase span value of the heat released by the exothermic reaction inside the battery cell to the corresponding span value of the reaction speed increase span of the endothermic reaction, and the continuous increase frequency of the corresponding ratio of the number of exothermic reactions to the number of endothermic reactions when the heat released by the exothermic reaction inside the current battery cell of the energy storage battery increases, and they are respectively labeled as KDZ, KDB, and CPL.

4. The thermal runaway diffusion test method of an energy storage battery according to claim 1, characterized in that: The thermal runaway diffusion analysis and evaluation process is as follows: Collect supply performance information and controllable performance information, and if the supply performance information does not exceed the percentage decrease span threshold, and the controllable performance information does not exceed the energy increase span threshold, generate a low heat impact signal; If the supply performance information exceeds the percentage decrease span threshold, or the controllable performance information exceeds the energy increase span threshold, a high heat impact signal is generated; at the same time, the thermal runaway diffusion is analyzed and predicted; The supply performance information and controllable performance information are respectively the decrease span corresponding to the average value of the real-time supply of the energy storage battery controlled by the battery cell and the proportion of the supply demand in the current stage, and the increase span value of the non-decaying energy inside the battery cell during the non-overlapping period of the energy decay period and the energy increase period inside the battery cell.

5. A thermal runaway diffusion test method for an energy storage battery according to claim 4, characterized in that: Collect temperature rise gradient parameters and mechanical loss parameters. If the temperature rise gradient parameter exceeds the temperature gradient span threshold, or the mechanical loss parameter exceeds the loss span threshold, a heat diffusion signal is generated; if the temperature rise gradient parameter does not exceed the temperature gradient span threshold, and the mechanical loss parameter does not exceed the loss span threshold, a non-diffusion signal is generated; The temperature rise gradient parameter and mechanical loss parameter are respectively the expansion span of the temperature gradient in the thickness direction of the battery after thermal runaway occurs inside the energy storage battery, and the increase span of the mechanical loss amount exceeding the loss mean at any position on the internal surface of the battery under the current thermal environment of the energy storage battery.

6. A thermal runaway diffusion test method for an energy storage battery according to claim 1, characterized in that: When the diffusion direction is the anti-gravity direction, a gas arc is obtained. If the gas arc in the anti-gravity direction corresponds to a high-density gas, which is a combustible gas, the administrator will protect the area according to the corresponding gas type; if the gas arc in the anti-gravity direction corresponds to a low-density gas, which is a combustible gas, the administrator will perform flame spray protection according to the characteristics of the leaked diffusion gas.

7. A thermal runaway diffusion test method for an energy storage battery according to claim 1, characterized in that: The traceability control process is as follows: Collect the proportion coefficient and speed coefficient. If the proportion coefficient exceeds the number proportion threshold and the speed coefficient does not exceed the speed proportion threshold, a priority control signal is generated; if the proportion coefficient does not exceed the number proportion threshold, or the speed coefficient exceeds the speed proportion threshold, a priority protection signal is generated; The proportion coefficient is the ratio of the proportion of the number of completed heat release controls to the total number of controls and the corresponding numerical ratio of the number of non-first heat release controls in the current number of abnormal risk reactants; The speed coefficient is the numerical ratio of the speed of shortening the interval time of diffusion after the risk reactant thermal runaway occurs to the speed of increasing the duration of expansion.

8. A thermal runaway diffusion test system for energy storage batteries, characterized in that: A thermal runaway diffusion test method for an energy storage battery as described in any one of claims 1 to 7 above is applied.

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