Battery thermal runaway simulation analysis method, system, device and storage medium

Abstract

This application provides a battery thermal runaway simulation analysis method, system, device, and storage medium. The method includes: building a thermal runaway simulation model based on the battery structure; heating the target cell externally to reach the self-generating heat initiation temperature, controlling the target cell to generate heat to reach the thermal runaway temperature, and recording the first temperature change trend graph of the target cell and each neighboring cell before thermal runaway and the thermal runaway time of the target cell; transferring the heat generated by the target cell to each neighboring cell, and monitoring the second temperature change trend graph of the target cell and each neighboring cell during the thermal runaway time period; generating a temperature change comparison graph based on the first and second temperature change trend graphs and the theoretical temperature change trend graph of the target cell and neighboring cells; judging the simulation accuracy based on the temperature change comparison graph, and completing the battery thermal runaway simulation analysis. This method effectively reduces the cost of battery thermal runaway analysis, better reflects the actual application of batteries, and makes the thermal runaway analysis results more reliable.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a method, system, device, and storage medium for simulating and analyzing battery thermal runaway. Background Technology

[0002] With the rapid development and widespread adoption of electric vehicles, the safety of electric vehicle power batteries has received increasing attention. Due to the relatively reactive chemical properties of power batteries, they are prone to thermal runaway under mechanical, electrical, and thermal abuse, which can easily lead to thermal propagation within the battery pack, causing serious harm to the electric vehicle and its occupants. To prevent thermal propagation between modules and cells within the entire power battery pack, electric vehicle power batteries are equipped with thermal runaway protection measures. As a crucial component of electric vehicles, the safety of power batteries is of paramount importance. Therefore, it is necessary to assess and analyze power battery thermal runaway to guide the optimization of thermal runaway protection design schemes and improve the overall vehicle safety.

[0003] In related technologies, methods for analyzing thermal runaway of power batteries include experimental methods and simulation analysis methods. Chinese patent CN113917344A discloses a method, device, and system for protecting against thermal runaway in power batteries. This method controls fire extinguishing after a power battery fire and obtains the completed thermal runaway test conditions to analyze the thermal runaway and reduce overall vehicle safety hazards. Chinese patent CN116380770A discloses a method and device for testing and analyzing thermal runaway in power batteries. This method conducts thermal runaway experiments on battery cells with different warning forces, and then conducts thermal runaway experiments on cells with heat insulation films under the optimal warning force to analyze the thermal runaway and provide targeted and effective protection against thermal runaway. However, the above experimental methods involve complex test scenarios and expensive equipment, resulting in high test costs. Furthermore, they do not fully consider the actual application conditions of power batteries, leading to low reliability of the analysis and test results for thermal runaway.

[0004] Therefore, it is necessary to propose a power battery thermal runaway simulation analysis scheme that can effectively reduce the cost of power battery thermal runaway analysis, better reflect the actual application of power batteries, and make the thermal runaway analysis results more credible. Summary of the Invention

[0005] To provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not intended as a general commentary, nor is it intended to identify key / important components or describe the scope of protection of these embodiments, but rather as a prelude to the detailed description that follows.

[0006] In view of the shortcomings of the prior art described above, the present invention discloses a battery thermal runaway simulation analysis method, system, device and storage medium to solve the technical problems of high cost of battery thermal runaway analysis and inaccurate thermal runaway analysis results due to the failure to accurately reproduce the actual use of batteries.

[0007] In a first aspect, this application provides a battery thermal runaway simulation analysis method, the method comprising: constructing a thermal runaway simulation model of the battery based on its composition structure, wherein the simulation model includes a target cell module and multiple adjacent cells; firstly, externally heating the target cell until it reaches its self-heating initiation temperature, then controlling the target cell to generate heat until it reaches the temperature corresponding to thermal runaway, and recording the first temperature change trend graph of the target cell and each of the adjacent cells before the target cell reaches thermal runaway and the thermal runaway time of the target cell reaching thermal runaway; and then... The generated heat is transferred to each of the adjacent cells, and a second temperature change trend map of the target cell and each of the adjacent cells is monitored during the thermal runaway time period; a temperature change comparison map is generated based on the first temperature change trend map, the second temperature change trend map, and the theoretical temperature change trend map of the target cell and the adjacent cells; the highest temperature of the target cell in the temperature change comparison map is compared with the corresponding theoretical highest temperature, the highest temperature of the adjacent cells is compared with the corresponding theoretical highest temperature, and the thermal runaway time is compared with the theoretical thermal runaway time to determine the simulation accuracy, and the thermal runaway simulation analysis of the battery is completed.

[0008] In one embodiment of the present invention, the step of constructing a thermal runaway simulation model of the battery based on its composition structure includes: dividing the target cell module into a target cell, an internal thermal circuit unit, an aluminum shell thermal circuit unit, a heating unit, and a cell self-generated heat unit; encasing the target cell in an aluminum shell, wherein the aluminum shell and the target cell have thermal contact, and the six sides of the aluminum shell form the aluminum shell thermal circuit unit, and simulating the thermal circuit between the target cell and each side of the aluminum shell based on the aluminum shell thermal circuit unit and the internal thermal circuit unit; simulating the external heating of the target cell by heating the heating unit and the thermal contact between the aluminum shell and the target cell; simulating the self-generated heat of the target cell by heating the target cell through the cell self-generated heat unit; and protecting the target cell with the cell-insulating thermal unit, determining that the adjacent cells absorb heat from the aluminum shell, to simulate the thermal diffusion of the target cell to the adjacent cells.

[0009] In one embodiment of the present invention, the target battery cell is first heated externally until it reaches the self-heating initiation temperature, including: controlling a low-pass filter to output a first power to the PTC thermal capacitor element to heat the PTC thermal capacitor element; outputting heat flow through the PTC thermal capacitor element to the aluminum shell, and then through the aluminum shell to the target battery cell to heat the target battery cell; monitoring the first temperature of the target battery cell in real time through the temperature sensor, generating a temperature signal, and transmitting the temperature signal to the low-pass filter; the low-pass filter reads the temperature signal to obtain the first temperature, and compares the first temperature with the self-heating initiation temperature; if the first temperature is greater than or equal to the self-heating initiation temperature, the output of the first power to the PTC thermal capacitor element is stopped; if the first temperature is less than the self-heating initiation temperature, the output of the first power to the PTC thermal capacitor element continues until the target battery cell reaches the self-heating initiation temperature.

[0010] In one embodiment of the present invention, controlling the target battery cell to generate its own heat until it reaches the temperature corresponding to thermal runaway includes: controlling the battery cell self-heating unit to output a second power to the target battery cell; monitoring the second temperature of the target battery cell in real time, obtaining a time-temperature curve, and converting the time-temperature curve into a temperature-power curve; loading the temperature-power curve into a lookup table element of the battery cell self-heating unit in the form of interpolation to obtain the target battery cell self-heating power corresponding to the second temperature; integrating the target battery cell self-heating power over time to obtain the current target battery cell heat generation, and comparing the current target battery cell heat generation with the theoretical heat generation, wherein the theoretical heat generation is the target battery cell heat generation corresponding to the thermal runaway initiation temperature; if the current target battery cell heat generation is greater than or equal to the theoretical heat generation, then stopping the output of the second power to the target battery cell; if the current target battery cell heat generation is less than the theoretical heat generation, then continuing to output the second power to the target battery cell until the target battery cell reaches the temperature corresponding to thermal runaway.

[0011] In one embodiment of the present invention, the thermal runaway simulation model further includes an end plate and a frame unit, wherein the end plate and frame unit includes a heat-insulating end plate, an end plate and a frame, the heat-insulating end plate is respectively disposed at the end of a battery cell module formed by multiple cells arranged side by side, for balancing the temperature of cells at different positions in the cell module, the end plate is disposed on the outside of the heat-insulating end plate for fixing multiple cell modules in the battery, and the frame is disposed on the outside of the end plate for supporting the battery and resisting lateral impact.

[0012] In one embodiment of the present invention, the thermal runaway simulation model further includes a water-cooling unit, which includes a heat flow pipe element, a water-cooled plate heat capacity element, a cooling channel and a coolant. Each cell in the battery has an aluminum shell connected to a water-cooled plate heat capacity element and a heat flow pipe element, and the heat flow pipe elements and the water-cooled plate heat capacity elements are connected in series to simulate the heat dissipation device for each cell in the battery.

[0013] In one embodiment of the present invention, the water-cooling unit further includes a thermo-liquid container element. The method for simulating heat dissipation of the battery by the heat dissipation device includes: acquiring the power signal of the PTC thermal capacity element through the thermo-liquid container element; comparing the power signal with a preset threshold; if the power signal is greater than the preset threshold, using a first preset flow rate as the coolant inlet flow rate; if the power signal is less than or equal to the preset threshold, using a second preset flow rate as the coolant inlet flow rate; the first preset flow rate is a preset flow rate of the coolant before thermal runaway of the target cell, and the second preset flow rate is a preset flow rate of the coolant after thermal runaway of the target cell; and controlling the coolant to dissipate heat to each cell in the battery according to the coolant inlet flow rate.

[0014] In one embodiment of the present invention, the thermal conductivity of the target battery cell is anisotropic. The target battery cell is divided into multiple parts. The method further includes: equating the target battery cell with multiple battery cell thermal capacity elements, and connecting each battery cell thermal capacity element to a neighboring battery cell through the aluminum shell and the battery cell thermal separation unit, simulating the thermal runaway of each part of the target battery cell to its corresponding neighboring battery cell; and determining the thermal conductivity of each part of the target battery cell based on the highest temperature of the neighboring battery cell.

[0015] In one embodiment of the present invention, cells at different locations in the battery are used as target cells to construct different thermal runaway simulation models. The method further includes: recording temperature change comparison diagrams of the target cells at different locations when thermal runaway occurs; performing simulation analysis on the thermal runaway of the target cells at different locations based on each temperature change comparison diagram, and determining the simulation accuracy of each thermal runaway simulation model.

[0016] In one embodiment of the present invention, the cell thermal insulation unit is made of thermal insulation material. By comparing the highest temperature of the adjacent cells when using thermal runaway simulation models with different thermal insulation materials, the performance of different thermal insulation materials in blocking heat flow transfer is determined, and optimization measures for battery thermal runaway protection are formulated.

[0017] Secondly, this application provides a battery thermal runaway simulation analysis system, the system comprising: a construction module, used to build a thermal runaway simulation model of the battery based on the battery's composition structure, wherein the simulation model includes a target cell module and multiple adjacent cells; a heating module, used to first heat the target cell externally until the target cell reaches its self-heating initiation temperature, then control the target cell to generate heat until it reaches the temperature corresponding to thermal runaway, and record the first temperature change trend graph of the target cell and each of the adjacent cells before the target cell reaches thermal runaway and the thermal runaway time of the target cell reaching thermal runaway; and a monitoring module, used to... The heat generated by the target cell is transferred to each of the adjacent cells, and a second temperature change trend map of the target cell and each of the adjacent cells is monitored during the thermal runaway time period; a generation module is used to generate a temperature change comparison map based on the first temperature change trend map, the second temperature change trend map, and the theoretical temperature change trend map of the target cell and the adjacent cells; an analysis module is used to compare the highest temperature of the target cell with the corresponding theoretical highest temperature, the highest temperature of the adjacent cells with the corresponding theoretical highest temperature, and the thermal runaway time with the theoretical thermal runaway time in the temperature change comparison map to determine the simulation accuracy, and complete the thermal runaway simulation analysis of the battery.

[0018] Thirdly, this application provides an electronic device, including: one or more processors; and a storage device for storing one or more programs, which, when executed by one or more processors, cause the electronic device to implement the safety state control method of the motor controller described in the first aspect.

[0019] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a computer's processor, causes the computer to perform the safety state control method for the motor controller described in the first aspect.

[0020] As described above, the battery thermal runaway simulation analysis method, system, device, and storage medium provided by the embodiments of the present invention have the following beneficial effects:

[0021] A one-dimensional thermal runaway simulation model of the battery is built based on its composition structure. This model simulates the external heating, internal self-generated heat, and heat diffusion from the target cell to neighboring cells within the battery, enabling simulation testing of battery thermal runaway. It fully considers the main thermal paths during thermal runaway and the actual operating scenarios of the battery, making the thermal runaway analysis results more reliable. A temperature change comparison chart is generated by combining the temperature change trend graphs of the target cell and neighboring cells obtained from the simulation test with the actual theoretical temperature change graphs of the target cell and neighboring cells. This reveals the temperature rise process of the target cell and neighboring cells during battery thermal runaway. The simulation accuracy of the thermal runaway simulation model can be judged based on the temperature change comparison chart, completing the battery thermal runaway simulation analysis. The thermal runaway simulation model has a simple structure and simulation logic, reducing the thermal runaway simulation cycle and effectively lowering the cost of battery thermal runaway analysis. Furthermore, the battery performance optimization design can be performed based on the simulation accuracy results, providing a reliable basis for battery thermal runaway protection methods and safety design.

[0022] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0024] Figure 1 This is a flowchart illustrating a battery thermal runaway simulation analysis method in an exemplary embodiment of this application;

[0025] Figure 2 This is a flowchart illustrating an exemplary embodiment of the present application of an externally heated target cell to its self-generated heat initiation temperature;

[0026] Figure 3 This is a schematic diagram of the structure of an externally heated target cell, as shown in an exemplary embodiment of this application;

[0027] Figure 4 This is a flowchart illustrating the self-heating process inside the target cell, as shown in an exemplary embodiment of this application;

[0028] Figure 5 This is a structural diagram of a battery thermal runaway simulation model illustrated in an exemplary embodiment of this application;

[0029] Figure 6 This is a flowchart illustrating the control of the coolant inlet flow rate, as shown in an exemplary embodiment of this application.

[0030] Figure 7 This is a schematic diagram of the internal thermal path of a target cell, illustrating an exemplary embodiment of this application;

[0031] Figure 8 This is a temperature change comparison diagram illustrating an exemplary embodiment of this application;

[0032] Figure 9 This is a structural diagram illustrating another battery thermal runaway simulation model, as shown in an exemplary embodiment of this application.

[0033] Figure 10 This is another temperature change comparison diagram shown in an exemplary embodiment of this application;

[0034] Figure 11 This is a block diagram illustrating a battery thermal runaway simulation analysis system, as shown in an exemplary embodiment of this application.

[0035] Figure 12 This is a schematic diagram of the structure of an electronic device provided in one embodiment of this application. Detailed Implementation

[0036] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0037] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0038] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0039] First, it's important to note that the chemical substances within batteries are highly reactive and prone to thermal runaway under mechanical, electrical, and thermal abuse. This can easily lead to thermal propagation within the battery pack, causing serious harm to electric vehicles and occupants. To prevent thermal propagation between modules and cells within the entire battery pack, electric vehicle power batteries are equipped with thermal runaway protection measures. Evaluating and analyzing battery thermal runaway to guide the optimization of thermal runaway protection design is essential to ensure overall vehicle safety. However, experimental methods in related technologies suffer from complex test scenarios and expensive equipment, resulting in high testing costs. Furthermore, they do not fully consider the actual application conditions of batteries, leading to low reliability of the analysis and test results regarding battery thermal runaway.

[0040] Therefore, please see Figure 1 , Figure 1 This is a flowchart illustrating a battery thermal runaway simulation analysis method according to an exemplary embodiment of this application. It should be understood that this method can also be applied to other exemplary implementation environments and specifically executed by devices in other implementation environments. This embodiment does not limit the implementation environment to which this method is applicable.

[0041] like Figure 1 As shown, in an exemplary embodiment, the battery thermal runaway simulation analysis method includes at least steps S110 to S150, which are described in detail below:

[0042] Step S110: Build a thermal runaway simulation model of the battery based on its composition and structure. The simulation model includes a target cell module and multiple adjacent cells.

[0043] It should be noted that the target cell refers to the cell that has thermal runaway due to mechanical abuse, electrical abuse, or thermal abuse, while the adjacent cell refers to the cell surrounding the target cell.

[0044] Specifically, a thermal runaway simulation model of the battery is built based on its composition structure, including: dividing the target cell module into the target cell, the internal thermal circuit unit of the cell, the aluminum shell thermal circuit unit, the heating unit, and the cell self-generated heat unit; using an aluminum shell to enclose the target cell, wherein the aluminum shell and the target cell have thermal contact, and the six sides of the aluminum shell form the aluminum shell thermal circuit unit, and simulating the thermal circuit between the target cell and each side of the aluminum shell based on the aluminum shell thermal circuit unit and the internal thermal circuit unit of the cell; simulating the external heating of the target cell by heating the heating unit and the thermal contact between the aluminum shell and the target cell; simulating the self-generated heat of the target cell by heating the target cell through the cell self-generated heat unit; and using a cell-insulating thermal unit for protection, determining the heat absorbed by the aluminum shell by adjacent cells, and simulating the heat diffusion of the target cell to adjacent cells.

[0045] In this embodiment, the aluminum shell thermal circuit unit is connected to the internal thermal circuit unit of the battery cell. The internal thermal circuit unit of the battery cell and the aluminum shell thermal circuit unit mainly transfer heat, simulating the thermal circuit of the target battery cell absorbing and dissipating heat. In addition, the heating unit is connected to the aluminum shell, the battery cell self-generating heat unit is connected to the aluminum shell, the aluminum shell and the battery cell are connected to the battery cell spacer thermal unit, and the battery cell spacer thermal unit is connected to the adjacent battery cell. In this way, the main thermal circuits in the battery thermal runaway process and the actual operating scenario of the battery are fully simulated. Moreover, a one-dimensional thermal runaway simulation model of the battery is built according to the battery composition structure. The thermal runaway simulation model has a simple structure and simulation logic, which reduces the thermal runaway simulation cycle and effectively reduces the cost of battery thermal runaway analysis.

[0046] It should also be noted that the cell thermal insulation unit simulates the thermal insulation layer between adjacent modules and between adjacent cells in the battery pack. The thermal insulation layer can reduce the thermal spread after a single cell is triggered to cause thermal runaway. The thermal runaway simulation model is equipped with a cell thermal insulation unit, so that while the thermal spread occurs after a single cell is triggered to cause thermal runaway, it also provides a certain degree of protection for the adjacent cells. In this way, it more realistically reflects the actual operation scenario of the battery.

[0047] Step S120: First, heat the outside of the target cell until the target cell reaches the self-heating start temperature. Then, control the target cell to generate heat until it reaches the temperature corresponding to thermal runaway. Record the first temperature change trend of the target cell and each neighboring cell before the target cell reaches thermal runaway and the thermal runaway time of the target cell.

[0048] During the external heating of the target cell and the self-generated heat of the target cell, the first temperature change trend of the target cell and each neighboring cell before the thermal runaway of the target cell and the thermal runaway time of the target cell are recorded. In this way, the temperature rise process of the target cell and neighboring cells before the thermal runaway of the battery is clearly shown, which is beneficial to the subsequent thermal runaway simulation analysis.

[0049] Specifically, please see Figure 2 , Figure 2 This is a flowchart illustrating an exemplary embodiment of the present application of externally heating the target cell to its self-heating initiation temperature, as shown in the following example. Figure 2As shown, the target cell is first heated externally until it reaches the self-generating heat initiation temperature, including at least steps S210 to S250, as follows: Step S210, the low-pass filter is controlled to output the first power to the PTC heat capacitor element to heat the PTC heat capacitor element; Step S220, the heat flow is output from the PTC heat capacitor element to the aluminum shell, and then flows to the target cell through the aluminum shell to heat the target cell; Step S230, the first temperature of the target cell is monitored in real time by a temperature sensor, a temperature signal is generated, and the temperature signal is transmitted to the low-pass filter; Step S240, the low-pass filter reads the temperature signal to obtain the first temperature and compares the first temperature with the self-generating heat initiation temperature; Step S250, if the first temperature is greater than or equal to the self-generating heat initiation temperature, the output of the first power to the PTC heat capacitor element is stopped; if the first temperature is less than the self-generating heat initiation temperature, the output of the first power to the PTC heat capacitor element continues until the target cell reaches the self-generating heat initiation temperature.

[0050] In this embodiment, the heating unit includes a temperature sensor, a low-pass filter, and a PTC thermal capacitor element. Please refer to [link / reference]. Figure 3 , Figure 3 This is a schematic diagram of the structure of an externally heated target cell, as shown in an exemplary embodiment of this application. Figure 3 As shown, a low-pass filter is connected to a PTC thermal capacitor element, outputting a first power to the PTC thermal capacitor element to heat it. The PTC thermal capacitor element is connected to an aluminum shell, and after being heated, it outputs heat flow to the aluminum shell, which then flows to the target battery cell to heat it. A temperature sensor is connected to the target battery cell and also to the low-pass filter. The temperature sensor can monitor the first temperature of the target battery cell in real time and generate a temperature signal that is transmitted to the low-pass filter. The low-pass filter obtains the first temperature based on the temperature signal and compares it with the self-heating initiation temperature. When the first temperature is greater than or equal to the self-heating initiation temperature, it indicates that the target battery cell has reached the self-heating temperature, and the output of the first power to the PTC thermal capacitor element is stopped to stop external heating of the target battery cell. When the first temperature is less than the self-heating initiation temperature, it indicates that the temperature of the target battery cell has not yet reached the self-heating initiation temperature, and the output of the first power to the PTC thermal capacitor element continues until the target battery cell reaches the self-heating initiation temperature.

[0051] This embodiment simulates the external heating of the target battery by heating the heating unit and the thermal contact between the aluminum shell and the target battery, i.e. the thermal path between the target battery and each surface of the aluminum shell. This simplifies the simulation logic of the external heating of the target battery, facilitates simulation operation, effectively shortens the simulation time, and saves manpower and resources.

[0052] Specifically, please see Figure 4 , Figure 4 This is a flowchart illustrating the self-heating process inside the target cell, as shown in an exemplary embodiment of this application. Figure 4As shown, controlling the target cell to generate its own heat until it reaches the temperature corresponding to thermal runaway includes at least steps S410 to S450, as follows: Step S410, controlling the cell's self-generating heat unit to output a second power to the target cell; Step S420, monitoring the second temperature of the target cell in real time, obtaining a time-temperature curve, and converting the time-temperature curve into a temperature-power curve; Step S430, loading the temperature-power curve into the lookup table element of the cell's self-generating heat unit in an interpolated form to obtain the target cell's self-generating heat corresponding to the second temperature. Heat generation power; Step S440, integrate the heat generation power of the target cell over time to obtain the current heat generation of the target cell, and compare the current heat generation of the target cell with the theoretical heat generation, where the theoretical heat generation is the heat generation of the target cell corresponding to the thermal runaway initiation temperature; Step S450, if the current heat generation of the target cell is greater than or equal to the theoretical heat generation, stop outputting the second power to the target cell; if the current heat generation of the target cell is less than the theoretical heat generation, continue outputting the second power to the target cell until the target cell reaches the temperature corresponding to thermal runaway.

[0053] Once a single battery cell reaches its self-heating temperature, chemical reactions begin to occur within its components, causing the temperature to rise further and gradually leading to thermal runaway. In this embodiment, the target battery cell is internally heated to the point of thermal runaway using a self-heating unit. It should be noted that the theoretical heat output is the heat output of the target battery cell at the temperature corresponding to the thermal runaway initiation point obtained in the experiment. If the current heat output of the target battery cell is greater than or equal to the theoretical heat output, it indicates that the temperature of the target battery cell has reached the temperature corresponding to thermal runaway, and the second power output to the target battery cell is stopped, thus stopping the internal heating of the target battery cell. If the current heat output of the target battery cell is less than the theoretical heat output, it indicates that the temperature of the target battery cell has not yet reached the temperature corresponding to thermal runaway, and the second power output to the target battery cell continues for internal heating until the target battery cell reaches the temperature corresponding to thermal runaway.

[0054] This embodiment heats the target cell using a cell self-heating unit, simulating the self-heating of the target cell. This simplifies the simulation logic of the target cell's self-heating, facilitates simulation operation, effectively shortens simulation time, and saves manpower and resources.

[0055] Step S130: The heat generated by the target cell is transferred to each neighboring cell, and the second temperature change trend graph of the target cell and each neighboring cell is monitored during the thermal runaway period.

[0056] After the target cell reaches the temperature corresponding to thermal runaway, the large amount of heat generated by the target cell will be transferred to the neighboring cells through the target cell thermal circuit formed by the internal thermal circuit unit and the aluminum shell thermal circuit unit. During the process of heat transfer from the target cell to the neighboring cells, a second temperature change trend graph of the target cell and the neighboring cells during the thermal runaway period is monitored. This clearly shows the temperature change process of the target cell and the neighboring cells during the battery thermal runaway period, which is beneficial for subsequent thermal runaway simulation analysis.

[0057] Step S140: Generate a temperature change comparison map based on the first temperature change trend map, the second temperature change trend map, and the theoretical temperature change trend map of the target cell and the adjacent cell.

[0058] It should be noted that the theoretical temperature change trend graph of the target cell and adjacent cells refers to the temperature change graph of the target cell and adjacent cells obtained throughout the entire process of thermal runaway of the battery during the experiment. Please refer to [link / reference]. Figure 8 , Figure 8 This is a temperature change comparison diagram illustrating an exemplary embodiment of this application, such as... Figure 8 As shown, the temperature change process of the target cell and the adjacent cells in the simulation and the temperature change process of the target cell and the adjacent cells in the experiment are clearly demonstrated.

[0059] Step S150: Compare the highest temperature of the target cell with the corresponding theoretical highest temperature, the highest temperature of the adjacent cell with the corresponding theoretical highest temperature, and the thermal runaway time with the theoretical thermal runaway time in the temperature change comparison chart to determine the simulation accuracy and complete the thermal runaway simulation analysis of the battery.

[0060] It should be noted that the theoretical maximum temperature corresponding to the target cell refers to the highest temperature of the target cell obtained during the entire process of thermal runaway in the experiment. The theoretical maximum temperature corresponding to the adjacent cell refers to the highest temperature of the adjacent cell obtained during the entire process of thermal runaway in the experiment. The theoretical thermal runaway time refers to the time during which the battery experiences thermal runaway in the experiment. By comparing the highest temperature of the target cell with its corresponding theoretical maximum temperature, the highest temperature of the adjacent cell with its corresponding theoretical maximum temperature, and the thermal runaway time with the theoretical thermal runaway time in the temperature change comparison graph, the accuracy of the thermal runaway simulation model can be determined based on the accuracy of the simulation results. This allows for battery performance optimization design and provides a reliable basis for battery thermal runaway protection methods and safety design.

[0061] In one embodiment, the thermal runaway simulation model further includes an end plate and a frame unit, wherein the end plate and frame unit includes a heat-insulating end plate, an end plate and a frame. The heat-insulating end plate is respectively disposed at the end of the battery cell module formed by multiple cells arranged side by side, for balancing the temperature of cells at different positions in the cell module. The end plate is disposed on the outside of the heat-insulating end plate for fixing the multiple cell modules in the battery. The frame is disposed on the outside of the end plate for supporting the battery and resisting lateral impact.

[0062] Please see Figure 5 , Figure 5 This is a structural diagram of a battery thermal runaway simulation model illustrated in an exemplary embodiment of this application, as shown below. Figure 5 As shown, the thermal runaway simulation model is set up with two modules, corresponding to two rows of cells, with multiple individual cells in each row. The thermal runaway simulation model includes a target cell module and multiple adjacent cells, while the remaining cells are simplified cells, i.e., cells less affected by the thermal runaway of the target cell.

[0063] It should be noted that the aluminum shell thermal circuit unit, the cell self-generating heat unit, and the cell internal thermal circuit unit in the target cell module are not correspondingly shown in the figure; the heat insulation layer between each cell and the aerogel between the modules in the figure are the cell heat insulation unit in the battery module. The heat insulation layer can be a device or material with heat insulation properties, and the aerogel can also be replaced by other devices or materials with heat insulation properties; the PTC plate in the figure is the heating unit.

[0064] In this embodiment, such as Figure 5 As shown, in the thermal runaway simulation model, the heat insulation end plates are respectively set at the ends of multiple battery cell modules formed by multiple cells arranged side by side. The end plates are set on the outside of the heat insulation end plates, and the frame is set on the outside of the end plates. In this way, the specific structure of the battery and the actual operating scenario of the battery are fully simulated, which can enhance the accuracy of the thermal runaway simulation results.

[0065] In one embodiment, the thermal runaway simulation model further includes a water-cooling unit, which includes a heat flow pipe element, a water-cooled plate heat capacity element, a cooling channel and a coolant. Each cell in the battery has an aluminum shell connected to a water-cooled plate heat capacity element and a heat flow pipe element, and the heat flow pipe elements and the water-cooled plate heat capacity elements are connected in series to simulate the heat dissipation device for each cell in the battery.

[0066] Please continue reading Figure 5It should be noted that in the thermal runaway simulation model, adjacent cells and simplified cells are also encased in aluminum shells. The thermal runaway simulation model also includes a water-cooling unit, namely the water-cooling plate shown in the figure. A serpentine flow channel water-cooling plate can be used to dissipate heat from the battery module; however, this embodiment does not limit the shape of the flow channel. The water-cooling unit includes heat flow pipe elements, water-cooling plate heat capacity elements, cooling channels, and coolant. Each cell's aluminum shell is connected to a water-cooling plate heat capacity element and a heat flow pipe element. These heat flow pipe elements and water-cooling plate heat capacity elements are connected in series, simulating the heat dissipation device used in actual battery operation to cool each cell. Additionally, the heat insulation end plate, end plate, and frame are also connected to a water-cooling plate heat capacity element and a heat flow pipe element, respectively. This fully simulates the specific structure of the battery and its actual operating scenarios, enhancing the accuracy of the thermal runaway simulation results.

[0067] In one embodiment, the water-cooling unit further includes a thermo-liquid container element for simulating a heat dissipation device to cool the battery; see [link to relevant documentation]. Figure 6 , Figure 6 This is a flowchart illustrating the control of the coolant inlet flow rate as shown in an exemplary embodiment of this application, such as... Figure 6 As shown, firstly, the power signal of the PTC thermal capacity element is obtained through the thermo-liquid container element; then, the power signal is compared with a preset threshold; further, if the power signal is greater than the preset threshold, the first preset flow rate is used as the coolant inlet flow rate, and if the power signal is less than or equal to the preset threshold, the second preset flow rate is used as the coolant inlet flow rate; finally, the coolant is controlled to dissipate heat from each cell in the battery according to the coolant inlet flow rate.

[0068] In this embodiment, the first preset flow rate is the preset flow rate of the coolant before thermal runaway of the target cell, and the second preset flow rate is the preset flow rate of the coolant after thermal runaway of the target cell. The inlet flow rates of the coolant before and after thermal runaway of the target cell are different. This fully simulates the specific structure of the battery and the actual operating scenario of the battery, which can enhance the accuracy of the thermal runaway simulation results.

[0069] It should also be noted that in the overall structure of the power battery pack, the cooling method has a significant impact on the temperature field distribution of the battery module. Depending on the different thermal management strategies, different cooling methods can be set in the model, such as natural cooling, air cooling, liquid cooling, direct cooling, etc.

[0070] In one embodiment, the thermal conductivity of the target cell is anisotropic. The target cell is divided into multiple parts. The method further includes: equating the target cell with multiple cell thermal capacity elements, and connecting each cell thermal capacity element to a neighboring cell through an aluminum shell and a cell-insulating thermal unit, simulating the thermal runaway of each part of the target cell to its corresponding neighboring cell, and determining the thermal conductivity of each part of the target cell based on the highest temperature of the neighboring cell.

[0071] In this embodiment, please refer to Figure 7 , Figure 7 This is a schematic diagram of the internal thermal path of a target cell, as shown in an exemplary embodiment of this application. Figure 7 As shown, multiple parts inside the target cell are equivalent to multiple cell heat capacity elements, such as 1-1, 2-1, 1-2, and 2-2 in the figure. Each part has heat conduction with the others. By setting the longitudinal and transverse heat conduction elements to different materials, the anisotropic heat transfer function of the cell can be achieved. It should be noted that in the thermal runaway simulation model, when the target cell is divided into multiple parts, each part is connected to a neighboring cell through an aluminum shell and a cell-spacer thermal unit. Each part must also be connected to a cell-self-generating heat unit, so that each part of the target cell has self-generating heat capability. The simulation simulates the thermal runaway of each part of the target cell to its corresponding neighboring cell. Furthermore, the thermal conductivity of each part of the target cell can be determined based on the highest temperature of the neighboring cells.

[0072] In one embodiment, the cell insulation unit uses insulation material. By comparing the highest temperature of adjacent cells when using thermal runaway simulation models with different insulation materials, the performance of different insulation materials in blocking heat flow transfer is determined, and optimization measures for battery thermal runaway protection are formulated.

[0073] As one possible implementation, by changing the thermal insulation material of the cell-interval thermal unit in the thermal runaway simulation model, the highest temperature of the adjacent cells will be different. The lower the highest temperature of the adjacent cells, the better the performance of the thermal insulation material in blocking heat flow transfer. Therefore, the optimization of battery thermal runaway protection measures can be achieved.

[0074] In one embodiment, cells at different locations in the battery are used as target cells to construct different thermal runaway simulation models. The method further includes: recording temperature change comparison charts of target cells at different locations when thermal runaway occurs; performing simulation analysis on the thermal runaway of target cells at different locations based on each temperature change comparison chart, and determining the simulation accuracy of each thermal runaway simulation model.

[0075] In this embodiment, the thermal runaway simulation model built using this method has high simulation accuracy and good compatibility, depending on the different target cell placement positions. While ensuring the accuracy of thermal runaway simulation, it also greatly improves the efficiency of thermal runaway simulation and reduces the cost of battery thermal runaway analysis.

[0076] In this embodiment, based on the different positions of the target cell in the battery, two schemes are given below.

[0077] Option 1: In the thermal runaway simulation model, the target cell is located at the edge.

[0078] Please continue reading Figure 6 , Figure 6 The thermal runaway simulation model shown is an example of a model where the target cell is located at the edge. It should be noted that the simulation operation of this thermal runaway model has been described in detail in the above method and will not be repeated here. After the simulation, a temperature change comparison chart is generated based on the monitored data. Please refer to [link to relevant documentation]. Figure 8 , Figure 8 This is a temperature change comparison diagram illustrating an exemplary embodiment of this application, such as... Figure 8 As shown, the thermal runaway time in the thermal runaway simulation model is basically consistent with the thermal runaway time in the experiment. The highest temperature of the target cell differs from the corresponding theoretical highest temperature by about 10℃, and the highest temperature of the adjacent cell differs from the corresponding theoretical highest temperature by about 20℃. The simulation accuracy reaches 90%.

[0079] It should be noted that, because only the temperature of the target cell side and the side of adjacent cells can be obtained in the battery thermal runaway test, the temperature of the target cell and the side of adjacent cells is also detected in the simulation when the battery is still in runaway. This makes the comparison results of the highest temperature of the target cell with the corresponding theoretical highest temperature, the highest temperature of the adjacent cells with the corresponding theoretical highest temperature, and the thermal runaway time with the theoretical thermal runaway time more accurate.

[0080] Option 2: The target cell is positioned in the middle of the thermal runaway simulation model.

[0081] Please see Figure 9 , Figure 9 This is a structural diagram illustrating another battery thermal runaway simulation model, as shown in an exemplary embodiment of this application. Figure 9 As shown, with Figure 6 The difference lies in the location of the target cell. Figure 9 The thermal runaway simulation model shown is an example of a model where the target cell is positioned in the middle. It should be noted that the simulation operation of this thermal runaway model has been described in detail in the above method and will not be repeated here. After the simulation, a temperature change comparison chart is generated based on the monitored data; please refer to [link / reference]. Figure 10 , Figure 10 This is another temperature change comparison diagram illustrated in an exemplary embodiment of this application, such as... Figure 10 As shown, the thermal runaway time in the thermal runaway simulation model has an error of less than 5% compared with the thermal runaway time in the experiment, the error between the highest temperature of the target cell and the corresponding theoretical highest temperature is less than 10%, and the error between the highest temperature of the adjacent cell and the corresponding theoretical highest temperature is less than 10%, indicating extremely high simulation accuracy.

[0082] The battery thermal runaway simulation analysis method provided in the above embodiments builds a one-dimensional thermal runaway simulation model of the battery based on its composition structure. This model simulates the external heating of the target cell, internal self-generated heat, and heat diffusion from the target cell to neighboring cells, enabling simulation testing of battery thermal runaway. It fully considers the main thermal paths during the battery thermal runaway process and the actual operating scenarios of the battery, making the thermal runaway analysis results more reliable. A temperature change comparison chart is generated by combining the temperature change trend diagrams of the target cell and neighboring cells obtained from the simulation test with the actual theoretical temperature change diagrams of the target cell and neighboring cells. This reveals the temperature change process of the target cell and neighboring cells during battery thermal runaway. The simulation accuracy of the thermal runaway simulation model can be judged based on the temperature change comparison chart, completing the battery thermal runaway simulation analysis. The thermal runaway simulation model has a simple structure and simulation logic, reducing the thermal runaway simulation cycle and effectively lowering the cost of battery thermal runaway analysis. Furthermore, battery performance optimization design can be performed based on the simulation accuracy results, providing a reliable basis for battery thermal runaway protection methods and safety design.

[0083] Please see Figure 11 , Figure 11 This is a block diagram illustrating a battery thermal runaway simulation analysis method system as shown in an exemplary embodiment of this application. It should be understood that this system can also be applied to other exemplary implementation environments and specifically executed by devices in other implementation environments. This embodiment does not limit the implementation environment to which the system is applicable.

[0084] like Figure 11 As shown, in an exemplary embodiment, the battery thermal runaway simulation analysis system 1100 includes at least a construction module 1110, a heating module 1120, a monitoring module 1130, a generation module 1140, and an analysis module 1150, which are described in detail below:

[0085] Module 1110 is used to build a thermal runaway simulation model of the battery based on the battery's composition and structure. The simulation model includes a target cell module and multiple adjacent cells.

[0086] The heating module 1120 is used to first heat the outside of the target cell until the target cell reaches the self-heating start temperature, then control the target cell to generate heat until it reaches the temperature corresponding to thermal runaway, and record the first temperature change trend of the target cell and each neighboring cell before the target cell reaches thermal runaway and the thermal runaway time of the target cell.

[0087] Monitoring module 1130 is used to transfer the heat generated by the target cell to each neighboring cell and monitor the second temperature change trend graph of the target cell and each neighboring cell during the thermal runaway period.

[0088] The generation module 1140 is used to generate a temperature change comparison map based on the first temperature change trend map, the second temperature change trend map, and the theoretical temperature change trend map of the target cell and the adjacent cell.

[0089] Analysis module 1150 is used to compare the highest temperature of the target cell with the corresponding theoretical highest temperature, the highest temperature of the adjacent cell with the corresponding theoretical highest temperature, and the thermal runaway time with the theoretical thermal runaway time in the temperature change comparison graph to determine the simulation accuracy and complete the thermal runaway simulation analysis of the battery.

[0090] It should be noted that the battery thermal runaway simulation analysis method system provided in the above embodiments and the battery thermal runaway simulation analysis method provided in the above embodiments belong to the same concept. The content of the operation of each module has been described in detail in the method embodiments, and will not be repeated here.

[0091] Please see Figure 12 , Figure 12 This is a schematic diagram of the structure of an electronic device provided in one embodiment of this application. Figure 12 A schematic diagram of a computer system suitable for implementing the embodiments of this application is shown. It should be noted that... Figure 12 The computer system 1200 of the electronic device shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0092] like Figure 12 As shown, the computer system 1200 includes a Central Processing Unit (CPU) 1201, which can perform various appropriate actions and processes, such as executing the methods described in the above embodiments, based on programs stored in Read-Only Memory (ROM) 1202 or programs loaded from storage portion 1208 into Random Access Memory (RAM) 1203. The RAM 1203 also stores various programs and data required for system operation. The CPU 1201, ROM 1202, and RAM 1203 are interconnected via a bus 1204. An Input / Output (I / O) interface 1205 is also connected to the bus 1204.

[0093] The following components are connected to I / O interface 1205: an input section 1206 including a keyboard, mouse, etc.; an output section 1207 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 1208 including a hard disk, etc.; and a communication section 1209 including a network interface card such as a LAN (Local Area Network) card, modem, etc. The communication section 1209 performs communication processing via a network such as the Internet. A drive 1212 is also connected to I / O interface 1205 as needed. Removable media 1211, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., are installed on drive 1210 as needed so that computer programs read from them can be installed into storage section 1208 as needed.

[0094] Specifically, according to embodiments of this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program including a computer program for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 1209, and / or installed from removable medium 1211. When the computer program is executed by central processing unit (CPU) 1201, it performs various functions defined in the system of this application.

[0095] It should be noted that the computer-readable medium shown in the embodiments of this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying a computer-readable computer program. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media can also be any computer-readable medium other than computer-readable storage media, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0096] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. Each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0097] The units described in the embodiments of the present invention can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0098] The present invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a computer's processor, causes the computer to perform the battery thermal runaway simulation analysis method as described above. This computer-readable storage medium may be included in the electronic device described in the above embodiments, or it may exist independently and not assembled into the electronic device.

[0099] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A battery thermal runaway simulation analysis method, characterized in that, The method includes: A thermal runaway simulation model of the battery is built based on the battery's composition and structure. The thermal runaway simulation model includes a target cell module and multiple adjacent cells. First, the target cell is heated externally until it reaches the self-heating initiation temperature. Then, the target cell is controlled to generate heat until it reaches the temperature corresponding to thermal runaway. The first temperature change trend graph of the target cell and each of the neighboring cells before the target cell reaches thermal runaway and the thermal runaway time of the target cell are recorded. The heat generated by the target cell is transferred to each of the neighboring cells, and a second temperature change trend graph of the target cell and each of the neighboring cells is monitored during the thermal runaway period. A temperature change comparison chart is generated based on the first temperature change trend chart, the second temperature change trend chart, and the theoretical temperature change trend chart of the target cell and the adjacent cell. The simulation accuracy is determined by comparing the highest temperature of the target cell with the corresponding theoretical highest temperature, the highest temperature of the adjacent cell with the corresponding theoretical highest temperature, and the thermal runaway time with the theoretical thermal runaway time in the temperature change comparison chart, thereby completing the thermal runaway simulation analysis of the battery. The thermal runaway simulation model also includes a water-cooling unit, which includes a heat flow pipe element, a water-cooled plate heat capacity element, a cooling channel and a coolant. Each cell in the battery has an aluminum shell connected to a water-cooled plate heat capacity element and a heat flow pipe element, and the heat flow pipe elements and the water-cooled plate heat capacity elements are connected in series to simulate the heat dissipation device for each cell in the battery.

2. The battery thermal runaway simulation analysis method according to claim 1, characterized in that, The process of building a thermal runaway simulation model of the battery based on its composition and structure includes: The target cell module is divided into a target cell, an internal thermal circuit unit, an aluminum shell thermal circuit unit, a heating unit, and a cell self-heating unit. The target battery cell is encased in an aluminum shell, wherein the aluminum shell and the target battery cell have thermal contact, and the six sides of the aluminum shell form the aluminum shell thermal circuit unit. The thermal circuit between the target battery cell and each side of the aluminum shell is simulated based on the aluminum shell thermal circuit unit and the internal thermal circuit unit of the battery cell. The external heating of the target battery cell is simulated by heating the heating unit and the thermal contact between the aluminum shell and the target battery cell. The self-heating of the target battery cell is simulated by heating the target battery cell using a self-heating unit. The target cell is protected by the cell-insulating heat unit, and the heat absorbed by the aluminum shell by the adjacent cell is determined to simulate the heat diffusion of the target cell to the adjacent cell.

3. The battery thermal runaway simulation analysis method according to claim 2, characterized in that, First, the target cell is externally heated until it reaches its self-heating initiation temperature, including: The low-pass filter outputs a first power to the PTC heat capacity element to heat the PTC heat capacity element; The PTC heat capacity element outputs heat flow to the aluminum shell, and then flows through the aluminum shell to the target cell to heat the target cell; The temperature sensor monitors the first temperature of the target cell in real time, generates a temperature signal, and transmits the temperature signal to the low-pass filter. The low-pass filter reads the temperature signal to obtain the first temperature and compares the first temperature with the self-generated heat start temperature. If the first temperature is greater than or equal to the self-generated heat initiation temperature, the output of the first power to the PTC thermal capacitor element is stopped; if the first temperature is less than the self-generated heat initiation temperature, the output of the first power to the PTC thermal capacitor element continues until the target cell reaches the self-generated heat initiation temperature.

4. The battery thermal runaway simulation analysis method according to claim 3, characterized in that, Controlling the target cell to generate its own heat until it reaches the temperature corresponding to thermal runaway includes: Control the cell's self-heating unit to output a second power to the target cell; The second temperature of the target cell is monitored in real time to obtain a time-temperature curve, and the time-temperature curve is converted into a temperature-power curve. The temperature-power curve is loaded into the lookup table element of the cell self-heating unit in the form of interpolation to obtain the target cell self-heating power corresponding to the second temperature; The heat generated by the target cell itself is integrated over time to obtain the current heat generation of the target cell, and the current heat generation of the target cell is compared with the theoretical heat generation, where the theoretical heat generation is the heat generation of the target cell corresponding to the thermal runaway initiation temperature. If the current heat generation of the target cell is greater than or equal to the theoretical heat generation, the second power output to the target cell is stopped. If the current heat generation of the target cell is less than the theoretical heat generation, the second power output to the target cell continues until the target cell reaches the temperature corresponding to thermal runaway.

5. The battery thermal runaway simulation analysis method according to any one of claims 1 to 4, characterized in that, The thermal runaway simulation model also includes an end plate and a frame unit, wherein the end plate and frame unit includes a heat-insulating end plate, an end plate and a frame. The heat-insulating end plate is respectively disposed at the end of the battery cell module formed by multiple cells arranged side by side, and is used to equalize the temperature of cells at different positions in the cell module. The end plate is disposed on the outside of the heat-insulating end plate and is used to fix the multiple cell modules in the battery. The frame is disposed on the outside of the end plate and is used to support the battery and resist lateral impact.

6. The battery thermal runaway simulation analysis method according to claim 5, characterized in that, The water-cooling unit further includes a thermo-liquid container element, and the device for simulating heat dissipation to cool the battery includes: The power signal of the PTC thermal capacity element is obtained through the hydrothermal container element; The power signal is compared with a preset threshold. If the power signal is greater than the preset threshold, the first preset flow rate is used as the coolant inlet flow rate; if the power signal is less than or equal to the preset threshold, the second preset flow rate is used as the coolant inlet flow rate. The first preset flow rate is the preset flow rate of the coolant before thermal runaway of the target cell, and the second preset flow rate is the preset flow rate of the coolant after thermal runaway of the target cell. The coolant is controlled to dissipate heat from each cell in the battery according to the coolant inlet flow rate.

7. The battery thermal runaway simulation analysis method according to any one of claims 2 to 4, characterized in that, The target battery cell has anisotropic thermal conductivity. The method further includes dividing the target battery cell into multiple parts: The target cell is equivalent to multiple cell thermal capacity elements, and each cell thermal capacity element is connected to a neighboring cell through the aluminum shell and the cell thermal separation unit, respectively simulating the thermal runaway of each part of the target cell to its corresponding neighboring cell. The thermal conductivity of each part of the target cell is determined based on the highest temperature of each neighboring cell.

8. The battery thermal runaway simulation analysis method according to claim 7, characterized in that, The method further includes constructing different thermal runaway simulation models by using cells at different locations within the battery as target cells. A comparison chart of temperature changes when the target cell experiences thermal runaway at different locations; Based on the temperature change comparison charts, the thermal runaway of the target cell at different locations was simulated and analyzed, and the simulation accuracy of each thermal runaway simulation model was determined.

9. The battery thermal runaway simulation analysis method according to any one of claims 2 to 4, characterized in that, The cell thermal insulation unit uses thermal insulation material. By comparing the highest temperature of the adjacent cells when using thermal runaway simulation models with different thermal insulation materials, the performance of different thermal insulation materials in blocking heat flow transfer is determined, and optimization measures for battery thermal runaway protection are formulated.

10. A battery thermal runaway simulation analysis system, characterized in that, The system includes: A construction module is used to build a thermal runaway simulation model of the battery based on the battery's composition structure. The thermal runaway simulation model includes a target cell module and multiple adjacent cells. The heating module is used to first heat the outside of the target cell until the target cell reaches the self-heating start temperature, then control the target cell to generate heat until it reaches the temperature corresponding to thermal runaway, and record the first temperature change trend graph of the target cell and each of the adjacent cells before the target cell reaches thermal runaway and the thermal runaway time of the target cell. The monitoring module is used to transfer the heat generated by the target cell to each of the adjacent cells and monitor the second temperature change trend graph of the target cell and each of the adjacent cells during the thermal runaway period. The generation module is used to generate a temperature change comparison map based on the first temperature change trend map, the second temperature change trend map, and the theoretical temperature change trend map of the target cell and the adjacent cell. The analysis module is used to compare the highest temperature of the target cell with the corresponding theoretical highest temperature, the highest temperature of the adjacent cell with the corresponding theoretical highest temperature, and the thermal runaway time with the theoretical thermal runaway time in the temperature change comparison graph to determine the simulation accuracy and complete the thermal runaway simulation analysis of the battery. The thermal runaway simulation model also includes a water-cooling unit, which includes a heat flow pipe element, a water-cooled plate heat capacity element, a cooling channel and a coolant. Each cell in the battery has an aluminum shell connected to a water-cooled plate heat capacity element and a heat flow pipe element, and the heat flow pipe elements and the water-cooled plate heat capacity elements are connected in series to simulate the heat dissipation device for each cell in the battery.

11. An electronic device, characterized in that, include: One or more processors; A storage device for storing one or more programs, which, when executed by one or more processors, cause the electronic device to implement the battery thermal runaway simulation analysis method as described in any one of claims 1 to 9.

12. A computer-readable storage medium, characterized in that, It stores computer-readable instructions, which, when executed by the computer's processor, cause the computer to perform the battery thermal runaway simulation analysis method according to any one of claims 1 to 9.

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