Failure analysis method and device for battery pack explosion-proof valve based on SPH particle method

Abstract

The present invention discloses a method and device for analyzing the failure of a battery pack explosion-proof valve based on the SPH particle method, which relates to the field of automobile experimental analysis. The method includes establishing a battery pack simulation model including the internal and external structures of the battery pack based on simulation software, and importing the simulation analysis software to set the fluid calculation domain and calculation boundary; defining the script of the movement law of the battery pack in the fluid calculation domain based on the standard high temperature and high pressure test process of the battery pack; setting the high temperature and high pressure test parameters of the battery pack, and setting a solver to monitor the cross-sectional pressure of the battery pack; calculating the surface pressure of the explosion-proof valve permeable membrane and the water volume fraction through the simulation analysis software to realize the failure analysis of the battery pack explosion-proof valve. The present invention can effectively perform the failure analysis of the battery pack explosion-proof valve.

Description

Technical Field

[0001] The present invention relates to the field of automobile experimental analysis, and in particular to a method and device for analyzing failure of a battery pack explosion-proof valve based on an SPH particle method. Background Art

[0002] At present, battery packs are basically equipped with explosion-proof valves. Common explosion-proof valves include exhaust valves, air pressure balance valves, etc. When a battery experiences thermal runaway, the battery releases a large amount of high-temperature gas, and the internal pressure of the battery pack rises sharply. In order to prevent the battery pack from rupturing, an exhaust valve is set on the battery pack shell. A pressure balance membrane is provided in the discharge channel of the air pressure balance valve. The pressure balance membrane can block water molecules from entering the battery pack. At the same time, oxygen and nitrogen molecules are allowed to freely enter the balance membrane to adjust the pressure inside and outside the battery pack to a balanced state to meet the requirements of IP67 (a protection safety level). When the battery in the battery pack experiences thermal runaway, the large amount of high-temperature gas released will break through the balance membrane in the air pressure balance valve and be discharged from the pressure balance valve.

[0003] Therefore, conducting high temperature and high pressure tests is an important sub-item in battery pack performance management. How to accurately output the pressure value acting on the explosion-proof valve diaphragm under the corresponding working conditions has aroused great interest among scholars at home and abroad. However, in the existing related numerical simulation research, the main software used is StarCCM+ (an analysis software), namely the VOF (Volume of Fluid, the ratio of the volume of the target fluid to the grid volume) method. This numerical method uses the Euler framework, which requires the computational domain to be meshed.

[0004] Then, since most working conditions need to consider the state of the battery pack on the whole vehicle, and the whole vehicle has many parts, the workload of meshing is very large. In addition, for high temperature and high pressure conditions, the movement law of the fluid inside and outside the battery pack is also relatively complicated. At the same time, the simulation calculation also needs to include the vehicle going downhill, uphill, and wheel rotation. It can be seen that the VOF method is difficult to define such a complex motion boundary, which is not conducive to the failure analysis of the battery pack explosion-proof valve. Summary of the invention

[0005] In view of the defects existing in the prior art, the object of the present invention is to provide a method and device for failure analysis of battery pack explosion-proof valve based on SPH particle method, which can effectively perform failure analysis of battery pack explosion-proof valve.

[0006] In order to achieve the above objectives, the present invention provides a battery pack explosion-proof valve failure analysis method based on the SPH particle method, which specifically includes the following steps:

[0007] A battery pack simulation model including the internal and external structures of the battery pack is established based on the simulation software, and then imported into the simulation analysis software to set the fluid calculation domain and calculation boundary;

[0008] Define the script for the movement of the battery pack in the fluid calculation domain based on the standard high temperature and high pressure test process for the battery pack;

[0009] Set the parameters for high temperature and high pressure tests on battery packs, and set up a solver to monitor the cross-sectional pressure of the battery packs;

[0010] The surface pressure of the explosion-proof valve permeable membrane and the water volume fraction are calculated by simulation analysis software to realize the failure analysis of the battery pack explosion-proof valve.

[0011] On the basis of the above technical solution, the battery pack simulation model including the internal and external structures of the battery pack is established based on the simulation software, and the specific steps include:

[0012] Obtain the overall CAD model of the battery pack and import the obtained CAD model into CAE pre-processing software;

[0013] The CAD model is converted into an STL format model through CAE pre-processing software to obtain a battery pack simulation model, which includes an explosion-proof valve and a battery cell.

[0014] On the basis of the above technical solution, the simulation analysis software is imported to set the fluid calculation domain and calculation boundary, and the specific steps include:

[0015] Import the battery pack simulation model into the simulation analysis software;

[0016] Through the operation interface of the simulation analysis software, the fluid calculation domain is set, and the calculation boundary is planned according to the HPC computing resources.

[0017] On the basis of the above technical solution, the standard high temperature and high pressure test process of the battery pack is used to define the movement law script of the battery pack in the fluid calculation domain. The specific steps include:

[0018] Based on the standard high temperature and high pressure test process of the battery pack, the fluid movement law in the battery pack under high pressure conditions and the fluid movement law in the battery pack under high temperature conditions are set when the battery pack is in the fluid calculation domain;

[0019] Set the parameters of the test pool and set the coordinates of the battery pack at the bottom of the test pool.

[0020] On the basis of the above technical solution, the steps of setting the parameters of the high temperature and high pressure test of the battery pack and setting the solver to monitor the cross-sectional pressure of the battery pack include:

[0021] Determine the initial viscosity of the fluid in the battery pack and set the parameters for the high temperature and high pressure test of the battery pack according to the cooling material and cavity distribution in the battery pack;

[0022] Set the calculation time and configure the solver to monitor the pressure at a specified cross section in the battery pack.

[0023] On the basis of the above technical solution, the solver is set to monitor the pressure of a specified cross section in the battery pack, wherein the specific steps for solving the cross section pressure include:

[0024] The fluid in the battery pack is described by using a group of interacting particles;

[0025] By solving the dynamic equations of the particle group and tracking the motion trajectory of each particle, the distribution and development of the entire flow field in the battery pack are obtained, and the pressure value of the specified cross section in the battery pack is obtained.

[0026] Based on the above technical solution, the battery pack high temperature and high pressure test parameters include a voltage rise curve under high pressure conditions and a temperature rise curve under high temperature conditions.

[0027] On the basis of the above technical solution, the surface pressure of the explosion-proof valve permeable membrane and the water volume fraction are calculated by simulation analysis software to realize the failure analysis of the battery pack explosion-proof valve. The specific steps include:

[0028] The surface pressure and water volume fraction of the explosion-proof valve permeable membrane are calculated by simulation analysis software;

[0029] According to the design requirements, analyze whether the explosion-proof valve can be activated under high temperature and high pressure test conditions.

[0030] On the basis of the above technical solutions, after analyzing whether the explosion-proof valve can be activated in the high temperature and high pressure test state according to the design requirements, it also includes:

[0031] If the explosion-proof valve fails to be excited in the high temperature and high pressure test state, the explosion-proof valve permeable membrane parameters of the battery pack and the internal structure of the battery pack are adjusted, and the battery pack explosion-proof valve failure analysis method based on the SPH particle method is executed again to determine whether the explosion-proof valve can be excited in the high temperature and high pressure test state. If the explosion-proof valve fails to be excited in the high temperature and high pressure test state, the explosion-proof valve permeable membrane parameters of the battery pack and the internal structure of the battery pack are adjusted again, and the cycle is repeated until the explosion-proof valve can be excited in the high temperature and high pressure test state, thereby completing the battery pack explosion-proof valve failure analysis;

[0032] If the explosion-proof valve can be activated under high temperature and high pressure test conditions, the failure analysis of the battery pack explosion-proof valve is completed.

[0033] The present invention provides a battery pack explosion-proof valve failure analysis device based on the SPH particle method, comprising:

[0034] A setting module, which is used to establish a battery pack simulation model including the internal and external structures of the battery pack based on the simulation software, and import the simulation analysis software to set the fluid calculation domain and calculation boundary;

[0035] Definition module, which is used to define the script of the movement law of the battery pack in the fluid calculation domain based on the standard high temperature and high pressure test process of the battery pack;

[0036] An execution module, which is used to set the parameters of the high temperature and high pressure test of the battery pack and set the solver to monitor the cross-sectional pressure of the battery pack;

[0037] The analysis module is used to calculate the surface pressure and water volume fraction of the explosion-proof valve permeation membrane through simulation analysis software to realize failure analysis of the battery pack explosion-proof valve.

[0038] Compared with the prior art, the advantages of the present invention are: by establishing a battery pack simulation model including the internal and external structures of the battery pack based on the simulation software, and importing the simulation analysis software, setting the fluid calculation domain and the calculation boundary, and then defining the script of the movement law of the battery pack in the fluid calculation domain based on the standard high temperature and high pressure test process of the battery pack, and then setting the high temperature and high pressure test parameters of the battery pack, and setting the solver to monitor the cross-sectional pressure of the battery pack, finally, the surface pressure and water volume fraction of the explosion-proof valve permeable membrane are calculated by the simulation analysis software to realize the failure analysis of the battery pack explosion-proof valve, that is, the SPH method and the simulation analysis software are combined, which is more efficient than the traditional VOT method in the simulation process. Under the condition of the same computing resources, the SPH method can more accurately output the cloud map of the fluid movement inside and outside the battery pack in the battery pack failure condition, and at the same time output the surface pressure distribution of the battery pack explosion-proof valve permeable membrane at the critical point of failure, effectively improving the structural design accuracy and efficiency of the electric vehicle battery pack explosion-proof valve for overpressure and overtemperature conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 It is a flow chart of a method for analyzing failure of a battery pack explosion-proof valve based on the SPH particle method in an embodiment of the present invention;

[0041] Figure 2 Schematic diagram of the structure of a battery pack explosion-proof valve failure analysis device based on the SPH particle method in an embodiment of the present invention. DETAILED DESCRIPTION

[0042] The embodiment of the present invention provides a failure analysis method for a battery pack explosion-proof valve based on an SPH particle method. A battery pack simulation model including internal and external structures of a battery pack is established based on simulation software, and the simulation analysis software is imported to set the fluid calculation domain and the calculation boundary. Then, based on the standard high temperature and high pressure test process of the battery pack, a script for the movement law of the battery pack in the fluid calculation domain is defined. Then, the high temperature and high pressure test parameters of the battery pack are set, and a solver is set to monitor the cross-sectional pressure of the battery pack. Finally, the surface pressure and water volume fraction of the explosion-proof valve permeable membrane are calculated by the simulation analysis software to realize the failure analysis of the battery pack explosion-proof valve. That is, the SPH method and the simulation analysis software are combined. Compared with the traditional VOT method, the SPH method is more efficient in the simulation process. Under the condition of the same computing resources, the SPH method can more accurately output the cloud map of the fluid movement inside and outside the battery pack in the battery pack failure condition, and at the same time output the surface pressure distribution of the battery pack explosion-proof valve permeable membrane at the critical point of failure, effectively improving the structural design accuracy and efficiency of the electric vehicle battery pack explosion-proof valve for overpressure and overtemperature conditions. Correspondingly, an embodiment of the present invention also provides a battery pack explosion-proof valve failure analysis method based on the SPH particle method.

[0043] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments.

[0044] The embodiment of the present invention provides a battery pack explosion-proof valve failure analysis method based on the SPH particle method, which improves the structural design accuracy and efficiency of the electric vehicle battery pack explosion-proof valve for overpressure and overtemperature conditions. Based on SPH (smooth particle fluid dynamics method), the present invention establishes a simulation model of the fluid inside and outside the battery pack of an electric vehicle in the simulation analysis software, and combines the battery pack failure test to study the movement and pressure distribution of the fluid inside and outside the battery pack under overtemperature and overpressure conditions, while focusing on analyzing the failure performance of the battery pack explosion-proof valve. Through simulation and testing, the design of the battery pack sealing system is improved to ensure that the explosion-proof valve can still work normally under extreme conditions. Through structural optimization of the heat dissipation and pressure reduction strategies inside and outside the battery pack, the fluid mechanics simulation function of the simulation analysis software is also verified, indicating that it can efficiently support the optimization design of related performance of the battery pack of electric vehicles.

[0045] See also Figure 1 As shown, a battery pack explosion-proof valve failure analysis method based on the SPH particle method provided in an embodiment of the present invention specifically includes the following steps:

[0046] S1: A battery pack simulation model including the internal and external structures of the battery pack is established based on the simulation software, and the model is imported into the simulation analysis software to set the fluid calculation domain and calculation boundary. Specifically, the simulation analysis software may be AVL Preonlab software, which is a CFD (Computational Fluid Dynamics) simulation software based on the SPH method and using a gridless technology.

[0047] In the present invention, a battery pack simulation model including the internal and external structures of the battery pack is established based on simulation software, and the specific steps include:

[0048] S101: Obtaining an overall CAD (Computer-Aided Design) model of the battery pack, and importing the obtained CAD model into CAE (Computer Aided Engineering) pre-processing software;

[0049] S102: Convert the CAD model into an STL format model through CAE pre-processing software to obtain a battery pack simulation model, wherein the battery pack simulation model includes an explosion-proof valve and a battery cell.

[0050] That is, by converting the entire CAD model of the battery pack, CAE pre-processing software is used to obtain and convert it into an stl (Stereolithography) format model containing the internal and external structures of the battery pack explosion-proof valve, battery cells, etc., thereby constructing a battery pack simulation model.

[0051] In the present invention, simulation analysis software is introduced to set the fluid calculation domain and calculation boundary, and the specific steps include:

[0052] S111: importing the battery pack simulation model into the simulation analysis software;

[0053] S112: Setting the fluid calculation domain through the operation interface of the simulation analysis software, and planning the calculation boundary according to the HPC (High Performance Computing) computing resources.

[0054] Through simulation analysis software, the SPH method can be used to simulate the fluid inside and outside the gridless battery pack, so as to calculate and output the pressure distribution of the key surfaces of the battery pack. The SPH method was originally applied in the field of astrophysics to simulate asymmetric physical phenomena. Due to its good stability and predictability, it has gradually been expanded to the field of fluid mechanics. It has significant advantages in solving flow problems with free surfaces and large deformations. The SPH method is based on the Lagrangian framework and is a gridless method. The basic idea of ​​this method is to describe continuous fluids or solids with a group of interacting particles. Each particle carries various physical quantities, including mass, pressure, velocity, etc. By solving the dynamic equations of the particle group and tracking the motion trajectory of each particle, the distribution and development of the entire flow field can be obtained, and then the pressure value of the relevant surface can be solved.

[0055] S2: Define the script for the movement of the battery pack in the fluid calculation domain based on the standard high temperature and high pressure test process of the battery pack;

[0056] In the present invention, the movement law script of the battery pack in the fluid calculation domain is defined based on the standard high temperature and high pressure test process of the battery pack, and the specific steps include:

[0057] S201: Based on the standard high temperature and high pressure test process of the battery pack, set the fluid movement law in the battery pack under high pressure conditions and the fluid movement law in the battery pack under high temperature conditions when the battery pack is in the fluid calculation domain;

[0058] S202: Set the parameters of the test pool and set the coordinates of the battery pack at the bottom of the test pool.

[0059] That is, according to the existing national standard battery pack high temperature and high voltage test process, a script for the movement law of the battery pack in the fluid calculation domain is set.

[0060] It should be noted that, for battery packs, overpressure conditions refer to situations where the internal pressure of the battery pack is too high, exceeding the tolerance range of the explosion-proof valve, causing the valve to fail, and the internal pressure cannot be discharged normally, thereby causing an explosion accident of the battery pack. During the test, the battery pack is subjected to a water immersion high-pressure test to observe the reaction of the explosion-proof valve and pressure changes; overtemperature conditions refer to situations where the internal temperature of the battery pack is too high, exceeding the tolerance range of the explosion-proof valve, causing the valve to fail, and the internal heat cannot be discharged normally, thereby causing an explosion accident of the battery pack. During the test, the battery pack is placed in a high-temperature environment to observe the reaction of the explosion-proof valve and temperature changes.

[0061] S3: Setting the parameters of the high temperature and high pressure test of the battery pack, and setting the solver to monitor the cross-sectional pressure of the battery pack;

[0062] In the present invention, the high temperature and high pressure test parameters of the battery pack are set, and a solver is set to monitor the cross-sectional pressure of the battery pack. The specific steps include:

[0063] S301: Determine the initial viscosity of the fluid in the battery pack and set the high temperature and high pressure test parameters of the battery pack according to the cooling material in the battery pack and the distribution of the cavities in the battery pack; the high temperature and high pressure test parameters of the battery pack include the voltage rise curve under the high pressure condition and the temperature rise curve under the high temperature condition.

[0064] S302: Setting a calculation time portion and setting a solver to monitor the pressure of a specified cross section in the battery pack.

[0065] In the present invention, a solver is provided to monitor the pressure of a specified cross section in a battery pack, wherein the specific steps for solving the cross section pressure include:

[0066] S3021: Use interacting mass point groups to describe the fluid in the battery pack;

[0067] S3022: By solving the dynamic equations of the mass point group and tracking the motion trajectory of each mass point, the distribution and development of the entire flow field in the battery pack are obtained, thereby solving the pressure value of the specified cross section in the battery pack. The specified cross section is the set key cross section of the battery pack.

[0068] S4: The surface pressure of the explosion-proof valve permeation membrane and the water volume fraction are calculated by simulation analysis software to realize the failure analysis of the battery pack explosion-proof valve.

[0069] In the present invention, the surface pressure of the explosion-proof valve permeable membrane and the water volume fraction are calculated by simulation analysis software to realize the failure analysis of the battery pack explosion-proof valve. The specific steps include:

[0070] S401: Calculate the surface pressure and water volume fraction of the explosion-proof valve permeable membrane through simulation analysis software;

[0071] S402: Analyze whether the explosion-proof valve can be activated in the high temperature and high pressure test state according to the design requirements. That is, analyze whether the explosion-proof valve can work normally in the high temperature and high pressure test state.

[0072] In the present invention, after analyzing whether the explosion-proof valve can be activated in a high temperature and high pressure test state according to design requirements, it also includes:

[0073] If the explosion-proof valve fails to be excited in the high temperature and high pressure test state, the explosion-proof valve permeable membrane parameters of the battery pack and the internal structure of the battery pack are adjusted, and the battery pack explosion-proof valve failure analysis method based on the SPH particle method is executed again to determine whether the explosion-proof valve can be excited in the high temperature and high pressure test state. If the explosion-proof valve fails to be excited in the high temperature and high pressure test state, the explosion-proof valve permeable membrane parameters of the battery pack and the internal structure of the battery pack are adjusted again, and the cycle is repeated until the explosion-proof valve can be excited in the high temperature and high pressure test state, thereby completing the battery pack explosion-proof valve failure analysis;

[0074] If the explosion-proof valve can be activated under high temperature and high pressure test conditions, the failure analysis of the battery pack explosion-proof valve is completed.

[0075] That is, when the explosion-proof valve fails to be activated under the high temperature and high pressure test state, the parameters such as the explosion-proof valve permeable membrane and the internal structure of the battery pack are optimized according to the failure situation and the actual project situation of the battery pack, and then steps S1 to S4 are executed again to finally complete the verification and optimization of the battery pack explosion-proof valve performance under high temperature and high pressure conditions.

[0076] The present invention can improve the simulation accuracy and efficiency of the failure condition of the explosion-proof valve of the battery pack of new energy vehicles. The SPH method adopts the Lagrangian framework and does not require grid division, thereby avoiding the problems of grid refinement, reconstruction, distortion, etc. of the VOF (Euler method) method, and can flexibly define the movement law of the boundary, making the simulation related to thermodynamics and fluid in the failure condition of the battery pack explosion-proof valve simpler and the modeling close to reality. The present invention establishes a simulation model of the high temperature and high pressure working condition of the battery pack of new energy vehicles, and combines the failure test of the battery pack explosion-proof valve to study the movement and distribution law of the fluid inside and outside the battery pack during the process of the battery pack explosion-proof valve approaching failure under high temperature and high pressure working conditions, focusing on evaluating the pressure distribution cloud map of the battery pack explosion-proof valve membrane at the critical point of failure. While improving the simulation accuracy and efficiency, it has important guiding significance for the optimization design of the safety performance of the battery pack of electric vehicles.

[0077] In the present invention, the SPH method and simulation analysis software are more efficient in the simulation process than the traditional VOT method (i.e. StarCCM+). Under the condition of the same computing resources, the SPH method can more accurately output the cloud map of the fluid movement inside and outside the battery pack under the battery pack failure (high temperature, high pressure) condition, and at the same time output the surface pressure distribution of the battery pack explosion-proof valve permeable membrane at the critical point of failure. The battery pack safety performance optimization and verification scheme is promoted based on the simulation analysis data and combined with the experimental results. The SPH method provides sufficient pre-research and prediction data for the battery pack explosion-proof valve failure condition experiment, and at the same time greatly reduces the verification rounds of the later optimization scheme, truly comprehensively improving the business level in the field of new energy vehicle battery pack safety performance simulation from the three aspects of quality, efficiency, and cost.

[0078] The battery pack explosion-proof valve failure analysis method based on the SPH particle method of the embodiment of the present invention establishes a battery pack simulation model including the internal and external structures of the battery pack based on simulation software, and imports the simulation analysis software to set the fluid calculation domain and the calculation boundary, and then defines the script of the movement law of the battery pack in the fluid calculation domain based on the standard high temperature and high pressure test process of the battery pack, and then sets the high temperature and high pressure test parameters of the battery pack, and sets the solver to monitor the cross-sectional pressure of the battery pack. Finally, the surface pressure and water volume fraction of the explosion-proof valve permeable membrane are calculated by the simulation analysis software to realize the failure analysis of the battery pack explosion-proof valve, that is, the combination of the SPH method and the simulation analysis software is more efficient than the traditional VOT method in the simulation process. Under the condition of the same computing resources, the SPH method can more accurately output the cloud map of the fluid movement inside and outside the battery pack in the battery pack failure condition, and at the same time output the surface pressure distribution of the battery pack explosion-proof valve permeable membrane at the critical point of failure, effectively improving the structural design accuracy and efficiency of the electric vehicle battery pack explosion-proof valve for overpressure and overtemperature conditions.

[0079] In a possible implementation, an embodiment of the present invention further provides a readable storage medium, the readable storage medium is located in a PLC (Programmable Logic Controller) controller, and a computer program is stored on the readable storage medium. When the program is executed by the processor, the following steps of the battery pack explosion-proof valve failure analysis method based on the SPH particle method are implemented:

[0080] A battery pack simulation model including the internal and external structures of the battery pack is established based on the simulation software, and then imported into the simulation analysis software to set the fluid calculation domain and calculation boundary;

[0081] Define the script for the movement of the battery pack in the fluid calculation domain based on the standard high temperature and high pressure test process for the battery pack;

[0082] Set the parameters for high temperature and high pressure tests on battery packs, and set up a solver to monitor the cross-sectional pressure of the battery packs;

[0083] The surface pressure of the explosion-proof valve permeable membrane and the water volume fraction are calculated by simulation analysis software to realize the failure analysis of the battery pack explosion-proof valve.

[0084] The storage medium may adopt any combination of one or more computer-readable media. The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium may be, for example, but not limited to: an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples (non-exhaustive list) of computer-readable storage media include: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this document, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, device or device.

[0085] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, which carry computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, device, or device. The program code contained on the computer-readable medium may be transmitted using any suitable medium, including but not limited to: wireless, wire, optical cable, RF, etc., or any suitable combination of the above.

[0086] Computer program code for performing the operations of the present invention may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0087] See also Figure 2As shown, an embodiment of the present invention provides a battery pack explosion-proof valve failure analysis device based on the SPH particle method, including a setting module, a definition module, an execution module and an analysis module.

[0088] The setting module is used to establish a battery pack simulation model including the internal and external structures of the battery pack based on the simulation software, and import the simulation analysis software to set the fluid calculation domain and calculation boundary; the definition module is used to define the script of the movement law of the battery pack in the fluid calculation domain based on the standard high temperature and high pressure test process of the battery pack; the execution module is used to set the high temperature and high pressure test parameters of the battery pack, and set the solver to monitor the cross-sectional pressure of the battery pack; the analysis module is used to calculate the surface pressure and water volume fraction of the explosion-proof valve permeation membrane through the simulation analysis software, so as to realize the failure analysis of the battery pack explosion-proof valve.

[0089] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

[0090] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems) and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the process in the flowchart. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

Claims

1. A battery pack explosion-proof valve failure analysis method based on the SPH particle method, characterized in that: The specific steps include: A battery pack simulation model including the internal and external structures of the battery pack is established based on the simulation software, and then imported into the simulation analysis software to set the fluid calculation domain and calculation boundary; Define the script for the movement of the battery pack in the fluid calculation domain based on the standard high temperature and high pressure test process for the battery pack; Set the parameters for high temperature and high pressure tests on battery packs, and set up a solver to monitor the cross-sectional pressure of the battery packs; The surface pressure of the explosion-proof valve permeation membrane and the water volume fraction are calculated by simulation analysis software to realize the failure analysis of the battery pack explosion-proof valve. The steps of setting the parameters of the high temperature and high pressure test of the battery pack and setting the solver to monitor the cross-sectional pressure of the battery pack include: Determine the initial viscosity of the fluid in the battery pack and set the parameters for the high temperature and high pressure test of the battery pack according to the cooling material and cavity distribution in the battery pack; Set the calculation time section and set the solver to monitor the pressure of the specified cross section in the battery pack; The solver is set to monitor the pressure of a specified cross section in the battery pack, wherein the specific steps for solving the cross section pressure include: The fluid in the battery pack is described by using a group of interacting particles; By solving the dynamic equations of the mass point group and tracking the motion trajectory of each mass point, the distribution and development of the entire flow field in the battery pack are obtained, thereby solving the pressure value of the specified cross section in the battery pack; Among them, the battery pack high temperature and high pressure test parameters include a voltage rise curve under high pressure conditions and a temperature rise curve under high temperature conditions.

2. A battery pack explosion-proof valve failure analysis method based on the SPH particle method as claimed in claim 1, characterized in that: The specific steps of establishing a battery pack simulation model including the internal and external structures of the battery pack based on the simulation software include: Obtain the overall CAD model of the battery pack and import the obtained CAD model into CAE pre-processing software; The CAD model is converted into an STL format model through CAE pre-processing software to obtain a battery pack simulation model, which includes an explosion-proof valve and a battery cell.

3. A battery pack explosion-proof valve failure analysis method based on the SPH particle method as claimed in claim 1, characterized in that: The step of importing the simulation analysis software to set the fluid calculation domain and calculation boundary includes: Import the battery pack simulation model into the simulation analysis software; Through the operation interface of the simulation analysis software, the fluid calculation domain is set, and the calculation boundary is planned according to the HPC computing resources.

4. A battery pack explosion-proof valve failure analysis method based on the SPH particle method as claimed in claim 1, characterized in that: The standard high temperature and high pressure test process for the battery pack is used to define the movement law script of the battery pack in the fluid calculation domain, and the specific steps include: Based on the standard high temperature and high pressure test process of the battery pack, the fluid movement law in the battery pack under high pressure conditions and the fluid movement law in the battery pack under high temperature conditions are set when the battery pack is in the fluid calculation domain; Set the parameters of the test pool and set the coordinates of the battery pack at the bottom of the test pool.

5. A battery pack explosion-proof valve failure analysis method based on the SPH particle method as claimed in claim 4, characterized in that: The simulation analysis software is used to calculate the surface pressure of the explosion-proof valve permeation membrane and the water volume fraction to implement failure analysis of the battery pack explosion-proof valve. The specific steps include: The surface pressure and water volume fraction of the explosion-proof valve permeable membrane are calculated by simulation analysis software; According to the design requirements, analyze whether the explosion-proof valve can be activated under high temperature and high pressure test conditions.

6. A battery pack explosion-proof valve failure analysis method based on the SPH particle method as claimed in claim 5, characterized in that: After analyzing whether the explosion-proof valve can be activated in the high temperature and high pressure test state according to the design requirements, it also includes: If the explosion-proof valve fails to be excited in the high temperature and high pressure test state, the explosion-proof valve permeable membrane parameters of the battery pack and the internal structure of the battery pack are adjusted, and the battery pack explosion-proof valve failure analysis method based on the SPH particle method is executed again to determine whether the explosion-proof valve can be excited in the high temperature and high pressure test state. If the explosion-proof valve fails to be excited in the high temperature and high pressure test state, the explosion-proof valve permeable membrane parameters of the battery pack and the internal structure of the battery pack are adjusted again, and the cycle is repeated until the explosion-proof valve can be excited in the high temperature and high pressure test state, thereby completing the battery pack explosion-proof valve failure analysis; If the explosion-proof valve can be activated under high temperature and high pressure test conditions, the failure analysis of the battery pack explosion-proof valve is completed.

7. A battery pack explosion-proof valve failure analysis device based on the SPH particle method, characterized in that: include: A setting module, which is used to establish a battery pack simulation model including the internal and external structures of the battery pack based on the simulation software, and import the simulation analysis software to set the fluid calculation domain and calculation boundary; Definition module, which is used to define the script of the movement law of the battery pack in the fluid calculation domain based on the standard high temperature and high pressure test process of the battery pack; An execution module, which is used to set the parameters of the high temperature and high pressure test of the battery pack and set the solver to monitor the cross-sectional pressure of the battery pack; An analysis module is used to calculate the surface pressure and water volume fraction of the explosion-proof valve permeation membrane through simulation analysis software to achieve failure analysis of the battery pack explosion-proof valve; The steps of setting the parameters of the high temperature and high pressure test of the battery pack and setting the solver to monitor the cross-sectional pressure of the battery pack include: Determine the initial viscosity of the fluid in the battery pack and set the parameters for the high temperature and high pressure test of the battery pack according to the cooling material and cavity distribution in the battery pack; Set the calculation time section and set the solver to monitor the pressure of the specified cross section in the battery pack; The solver is set to monitor the pressure of a specified cross section in the battery pack, wherein the specific steps for solving the cross section pressure include: The fluid in the battery pack is described by using a group of interacting particles; By solving the dynamic equations of the mass point group and tracking the motion trajectory of each mass point, the distribution and development of the entire flow field in the battery pack are obtained, thereby solving the pressure value of the specified cross section in the battery pack; Among them, the battery pack high temperature and high pressure test parameters include a voltage rise curve under high pressure conditions and a temperature rise curve under high temperature conditions.

Images