An expansion evaluation method, device and equipment of a power battery module and a storage medium
Patent Information
- Application Number
- CN202611213810.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-11
- Publication Date
- 2026-11-03
AI Technical Summary
Existing technologies cannot monitor the expansion of power battery modules in real time during their life cycle, making it difficult to identify problems such as loose bolts and loose electrical connections in the early stages. Furthermore, the lack of multi-dimensional comprehensive evaluation methods leads to large deviations between test results and actual operating conditions, making it impossible to effectively guide structural optimization.
By synchronously collecting multi-dimensional test information throughout the entire life cycle, including expansion force, end plate displacement, bolt temperature, etc., and combining temperature gradient, expansion displacement and bolt constraint reliability evaluation, an integrated comprehensive judgment of the module expansion suppression effect can be achieved.
It enables early warning of problems such as bolt loosening during the life cycle, avoids the exposure of problems in the later stage of the test, improves the accuracy of evaluation results and engineering guidance value, and can efficiently verify the design rationality of the module structure.
Smart Images
Figure CN123029383A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of power battery system testing technology, and in particular to a method, apparatus, equipment and storage medium for evaluating the expansion of a power battery module. Background Technology
[0002] Lithium-ion battery cells undergo continuous and irreversible volume expansion during charge-discharge cycles and long-term aging. The resulting compressive forces directly impact the module endplate, copper busbar connecting bolts, bottom adhesive structure, and housing constraint structure, easily leading to a series of failure issues such as bolt torque decay, loose copper busbar connections, unbalanced cell temperature distribution, structural adhesive detachment, and residual module deformation. These issues severely affect the structural stability, electrical connection reliability, and long-term safety of the power battery module and the entire vehicle battery system. Current industry testing and evaluation methods for power battery module expansion suppression performance have significant shortcomings, failing to fully and accurately replicate real-vehicle operating conditions and achieve comprehensive, multi-dimensional assessment throughout the entire lifecycle. Specific technical deficiencies are as follows:
[0003] First, existing tests can only collect physical quantities such as expansion force and end plate displacement, without establishing a correlation evaluation logic between cell expansion deformation, copper busbar bolt loosening, and abnormal module temperature gradient. This makes it impossible to identify potential electrical connection loosening hazards in advance through temperature distribution changes, relying solely on delayed risk assessment of bolt torque after test disassembly. This delayed fault detection easily leads to significant waste of test samples, equipment, and testing time. Second, there is a lack of a real-time dynamic evaluation mechanism during the life cycle process. Traditional tests can only uniformly detect deformation and torque data after the cycle test, failing to capture early characteristics of bolt loosening and expansion suppression failure in real time through temperature gradient changes during the cycle. This makes it difficult to provide early warnings of safety risks such as thermal runaway and excessive contact resistance, and cannot support rapid iterative optimization of module structural design. Third, a complete evaluation system integrating temperature gradient monitoring, expansion displacement monitoring, bolt residual torque detection, and vehicle-level vibration verification has not been formed. Existing solutions only conduct expansion force tests or vibration durability tests separately. The test data are independent of each other and cannot be analyzed in conjunction with each other. They cannot comprehensively evaluate the overall reliability of the end plate structure, copper busbar connection structure, and box constraint structure in resisting the long-term expansion force of the battery cell. The test results deviate from the mass production assembly conditions of the whole vehicle, and the engineering guidance value is limited.
[0004] In summary, the industry currently lacks an integrated method for evaluating the expansion suppression effect of power battery modules that can simultaneously simulate real-vehicle thermal management, charge-discharge life cycles, and housing constraint assembly conditions, collect multi-dimensional test information throughout the entire life cycle, and conduct layered real-time evaluation of temperature gradients, auxiliary evaluation of expansion displacement, and final verification of bolt constraint reliability. This makes it difficult to meet the precise verification needs of expansion suppression structures and housing constraint structures during the mass production development stage of power battery modules. Summary of the Invention
[0005] This application provides a method, apparatus, equipment, and storage medium for evaluating the expansion of a power battery module. By synchronously collecting multi-dimensional test information throughout the entire life cycle, it conducts a three-level evaluation of temperature gradient, expansion displacement, and bolt constraint reliability, thereby achieving an integrated and comprehensive judgment of the module's expansion suppression effect.
[0006] In a first aspect, embodiments of this application provide a method for evaluating the expansion of a power battery module, the method comprising:
[0007] During the entire life cycle of the power battery module under test, multi-dimensional test information of the power battery module under test is collected simultaneously.
[0008] Based on the multi-dimensional test information, the following evaluations are performed in sequence: real-time temperature gradient comparison evaluation, module expansion displacement auxiliary evaluation, and life cycle rear plate bolt constraint reliability verification evaluation.
[0009] Based on the real-time temperature gradient comparison evaluation, the module expansion displacement auxiliary evaluation, and the life cycle rear plate bolt constraint reliability verification evaluation, the expansion determination result of the power battery module under test is comprehensively output.
[0010] Secondly, embodiments of this application also provide an expansion evaluation device for a power battery module, the device comprising: a data acquisition module, a verification and evaluation module, and a result determination module; wherein,
[0011] The data acquisition module is used to synchronously collect multi-dimensional test information of the power battery module under test throughout the entire life cycle of the power battery module under test.
[0012] The verification and evaluation module is used to perform real-time temperature gradient comparison evaluation, module expansion displacement auxiliary evaluation, and life cycle rear plate bolt constraint reliability verification and evaluation sequentially based on the multi-dimensional test information.
[0013] The result judgment module is used to comprehensively output the expansion judgment result of the power battery module under test based on the real-time comparison evaluation of the temperature gradient, the auxiliary evaluation of the module expansion displacement, and the reliability verification evaluation of the bolt constraint of the life cycle end plate.
[0014] Thirdly, embodiments of this application provide an electronic device, including:
[0015] One or more processors;
[0016] Memory, used to store one or more programs.
[0017] When the one or more programs are executed by the one or more processors, the one or more processors implement the expansion evaluation method for the power battery module described in any embodiment of this application.
[0018] Fourthly, embodiments of this application provide a storage medium storing a computer program thereon, which, when executed by a processor, implements the expansion evaluation method for the power battery module described in any embodiment of this application.
[0019] This application proposes a method, device, equipment, and storage medium for evaluating the expansion of a power battery module. It synchronously collects multi-dimensional test information throughout the entire life cycle of the module, using real-time temperature gradient comparison to provide early warning of bolt loosening and expansion defects, avoiding the waste of cycle and sample resources caused by problems only being exposed later in the test. Combined with expansion displacement indicators to quantify the module's deformation control level, and further combined with post-cycle bolt residual torque detection and vehicle-level vibration verification to complete the final verification of constraint reliability, a hierarchical integrated evaluation system is formed, fully covering various failure modes caused by cell expansion. Simultaneously, multi-source temperature data can be cross-calibrated to eliminate errors caused by single sampling. Combined with test conditions replicating mass production assembly and real-vehicle thermal management composite operating conditions, it significantly improves the accuracy and engineering guidance value of the expansion suppression effect judgment results. The entire process can automatically complete data acquisition and hierarchical analysis, with high test consistency, and can efficiently and comprehensively verify the design rationality of the module end plate, copper busbar, and housing constraint structure. Therefore, compared with the prior art, the expansion evaluation method, device, equipment and storage medium of the power battery module proposed in this application realizes the integrated comprehensive judgment of the module expansion suppression effect by synchronously collecting multi-dimensional test information throughout the entire life cycle, and carrying out three-level evaluation of temperature gradient, expansion displacement and bolt constraint reliability in a layered manner; moreover, the technical solution of this application is simple and convenient to implement, easy to popularize, and has a wider range of applications. Attached Figure Description
[0020] Figure 1 A schematic flowchart of an expansion evaluation method for a power battery module provided in an embodiment of this application;
[0021] Figure 2 This is a schematic diagram of a method for real-time comparison and evaluation of temperature gradients based on multi-dimensional test information, provided in an embodiment of this application.
[0022] Figure 3 A schematic flowchart of a method for verifying and evaluating the reliability of back-end plate bolt constraints based on multi-dimensional test information during life cycle execution, provided in an embodiment of this application;
[0023] Figure 4 A schematic diagram of the structure of an expansion evaluation device for a power battery module provided in an embodiment of this application;
[0024] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation
[0025] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the application and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present application, not the entire structure.
[0026] Figure 1 This is a schematic flowchart illustrating a method for evaluating the expansion of a power battery module according to an embodiment of this application. This method can be executed by a power battery module expansion evaluation device or electronic device, which can be implemented in software and / or hardware, and can be integrated into any smart device with network communication capabilities. Figure 1 As shown, the expansion evaluation method for power battery modules may include the following steps:
[0027] S101. During the entire life cycle of the power battery module under test, multi-dimensional test information of the power battery module under test is collected synchronously.
[0028] In this step, multi-dimensional information such as expansion force, end plate displacement, independent temperature measurement data of bolts and cells, and cell voltage and temperature from the BMS are simultaneously collected under the complete life cycle conditions of the module. Multi-source data alignment is achieved using a unified timestamp, which not only fully replicates the entire process of continuous cell expansion under the coupling of vehicle charging / discharging, thermal management, and environment, but also establishes a data foundation for the correlation between cell expansion, structural deformation, and temperature rise. This solves the technical problems of fragmented data acquisition and the inability to analyze the relationship between expansion and temperature rise failure in existing technologies, providing complete, synchronous, and cross-verifiable original test data for subsequent stratified evaluation. The multi-dimensional test information in this application embodiment includes, but is not limited to: expansion force distribution information of the end plate and cell contact surface of the power battery module under test; instantaneous expansion displacement / cumulative displacement / residual deformation information of the two end plates of the power battery module under test; surface temperature information of the main positive bolt / main positive end cell / main negative end cell / main negative bolt of the power battery module under test; and cell temperature and single-cell voltage reference information reported by the BMS of the power battery module under test. The surface temperature information in this application embodiment includes at least: the maximum temperature NT1 of the main positive bolt of the power battery module under test, the maximum temperature NT2 of the first main positive cell of the power battery module under test, the maximum temperature NT3 of the first main negative cell of the power battery module under test, and the maximum temperature NT4 of the main negative bolt of the power battery module under test.
[0029] S102. Based on multi-dimensional test information, perform real-time temperature gradient comparison evaluation, module expansion displacement auxiliary evaluation, and life cycle rear plate bolt constraint reliability verification evaluation in sequence.
[0030] In this step, dynamic early warning of bolt loosening and connection deterioration risks during life cycle is first achieved through synchronous temperature gradient comparison throughout the entire process, identifying potential minor expansion failure hazards in advance. Then, expansion displacement data is used as an auxiliary indicator to quantify the module's macroscopic deformation control capability, supplementing the degree of structural deformation that cannot be characterized by temperature gradient. Finally, after the life cycle is completed, the reliability of the constrained structure is verified by bolt residual torque detection and standard vehicle vibration test. This covers the entire chain of failure judgment dimensions from real-time monitoring of the cycle process to endurance limit verification, breaking the limitations of traditional testing that relies solely on final inspection and lacks process early warning, and forming an integrated evaluation link of process early warning - deformation assistance - endurance verification.
[0031] S103. Based on real-time temperature gradient comparison evaluation, module expansion displacement auxiliary evaluation, and life cycle rear plate bolt constraint reliability verification evaluation, the expansion judgment result of the power battery module under test is comprehensively output.
[0032] In this step, instead of relying on a single indicator to evaluate the module's expansion suppression performance, a comprehensive assessment is made by integrating three different dimensions of evaluation conclusions: temperature gradient risk classification, expansion displacement deformation, and bolt torque attenuation and vibration test results. This approach can distinguish between different levels of problems, such as minor assembly deviations, connection structure defects, and enclosure constraint failures. It quantifies and outputs a unified and objective comprehensive judgment result on module expansion suppression, avoiding misjudgments caused by a single test indicator. The judgment conclusions can be directly used to guide the optimized design of end plates, copper busbars, and enclosure constraint structures, significantly improving the engineering reference value of the test results.
[0033] The expansion evaluation method for power battery modules proposed in this application synchronously collects multi-dimensional test information throughout the entire life cycle of the module. It relies on real-time temperature gradient comparison and evaluation to achieve early warning of bolt loosening and expansion defects, avoiding the waste of cycle and sample resources caused by problems only being exposed in the later stages of testing. Combined with expansion displacement indicators to assist in quantifying the module deformation control level, and further combined with bolt residual torque detection after cycling and vehicle-level vibration verification to complete the final verification of constraint reliability, a hierarchical integrated evaluation system is formed, fully covering various failure modes caused by cell expansion. Simultaneously, multi-source temperature data can be cross-calibrated to eliminate errors caused by single sampling. Combined with test conditions replicating mass production assembly and real vehicle thermal management composite operating conditions, the accuracy of the expansion suppression effect judgment results and its engineering guidance value are significantly improved. The entire process can automatically complete data acquisition and hierarchical analysis, with high test consistency, and can efficiently and comprehensively verify the design rationality of the module end plate, copper busbar, and housing constraint structure. Therefore, compared with the prior art, the expansion evaluation method of the power battery module proposed in this application realizes the integrated comprehensive judgment of the module expansion suppression effect by synchronously collecting multi-dimensional test information throughout the entire life cycle, and carrying out three-level evaluation of temperature gradient, expansion displacement and bolt constraint reliability in a layered manner; moreover, the technical solution of this application is simple and convenient to implement, easy to popularize, and has a wider range of applications.
[0034] Figure 2 This is a schematic flowchart illustrating a method for real-time temperature gradient comparison and evaluation based on multi-dimensional test information, provided in one embodiment of this application. Further optimizations and extensions can be made based on the above technical solution, and it can be combined with the various optional implementation methods described above. For example... Figure 2 As shown, the method for real-time comparative evaluation of temperature gradients based on multi-dimensional test information may include the following steps:
[0035] S201. Extract the externally independent measurement temperature and the BMS built-in measurement temperature corresponding to the first charge-discharge lifetime cycle, the nth charge-discharge lifetime cycle in the middle period, and the ith charge-discharge lifetime cycle in the later period, respectively; where n and i are one of the charge-discharge lifetime cycles in the middle period and the later period, respectively.
[0036] This step covers the three key stages of the life test: the early, middle, and late stages. It simultaneously retrieves the temperature data of bolts and end cells collected by external independent temperature measurement equipment, as well as the built-in temperature data of the module BMS. By using multi-source temperature measurement data in stages, a complete temperature evolution sample is retained. This not only tracks the dynamic change trend of temperature distribution during the long-term expansion and aging of the cells, but also uses the two sets of temperature measurement data to cross-check and eliminate single-point sampling errors. This provides complete and verifiable original temperature data for subsequent gradient ranking and risk comparison.
[0037] S202. Sort the measured temperatures of all temperature measurement points of the power battery module under test in the three cycle stages from high to low.
[0038] In this step, the temperatures of all points extracted from the three different cycle stages are standardized. The temperature values of all external temperature measurement points and BMS built-in battery cell temperature measurement points in each stage are uniformly sorted from high to low to complete the gradient sorting. The discrete single-point temperature values are transformed into an intuitive global temperature distribution sequence. This can eliminate the drawback of simply comparing the temperature difference of a single point, which makes it difficult to judge the overall thermal distribution shift. The temperature states of different cycle stages are transformed into a comparable unified sequence model, and an analysis carrier for horizontal comparison of multi-stage temperature changes is built.
[0039] S203. Compare the degree of temperature change in the three cyclic stages, and determine the risk level of copper busbar bolt loosening caused by cell expansion based on the degree of temperature change, so as to obtain a real-time comparative evaluation of temperature gradient.
[0040] In this step, the risk level of copper busbar bolt loosening caused by cell expansion is determined based on the degree of change in the temperature ranking. This can include the following steps: If the temperature ranking in the first cycle is from high to low as follows: main positive bolt temperature, main negative bolt temperature, BMS temperature of the middle cell of the power battery module under test, main positive end cell temperature, and main negative end cell temperature; and the temperature ranking in the nth cycle is from high to low as follows: main negative bolt temperature, main positive bolt temperature, BMS temperature of the middle cell of the power battery module under test, main negative end cell temperature, and main positive end cell temperature, then the risk level of loosening of the copper busbar bolts caused by cell expansion is determined. If only one side of the connecting bolts of the tested power battery module shows loosening and deviation, and the overall temperature distribution does not show a significant shift, it is considered a low-risk application. If, in the subsequent i-th cycle, the temperature ranking from high to low is: main negative bolt temperature, main positive bolt temperature, main negative end cell temperature, BMS-collected temperature of the cell in the middle of the module, and main positive end cell temperature, then the end cell temperature of the tested power battery module is determined to be outside the normal range. If the FPC sampling circuit of the tested power battery module does not cover the temperature measurement point of the end cell, then the copper busbar connection structure and the cell expansion suppression structure are directly determined to have design defects. This step relies on the temperature gradient sorting sequence generated in the first three stages to conduct a horizontal comparison. By observing the positional shift of high-temperature points and the magnitude of the high-low temperature sorting interchange, the degree of temperature distribution change is quantified. Combined with gradient shift characteristics, it distinguishes between low-risk conditions with only slight loosening of bolts on one side and high-risk structural defect conditions with significant temperature rise of the end cells. This enables real-time classification and judgment of the potential for loosening of copper busbar bolts caused by cell expansion, and outputs standardized temperature gradient evaluation conclusions. It can identify connection degradation problems in advance during the life cycle, solving the shortcomings of traditional tests that can only detect after the end of the test and have a lag in risk discovery.
[0041] The method for real-time comparative evaluation of temperature gradients based on multi-dimensional test information proposed in this application extracts external independent temperature measurement data and BMS built-in temperature measurement data simultaneously in the pre-, mid-, and post-stages, completely capturing the entire temperature evolution process under long-term expansion and aging of the battery cell. At the same time, it relies on dual-channel temperature measurement to achieve data cross-verification and reduce sampling errors. The temperature of all temperature measurement points in each stage is uniformly sorted from high to low, transforming discrete single-point temperatures into a standardized temperature gradient sequence that can be compared laterally, intuitively presenting the overall thermal distribution of the module. By comparing the offset of the temperature sorting in the three stages, the risk of bolt loosening is graded, which can identify potential connection degradation caused by expansion in real time during the life cycle. It can distinguish between mild risks and structural failures in advance without waiting for test disassembly. The combination of these three aspects solves the problems of single sampling stage, incomparable data, and delayed risk identification in traditional temperature evaluation, and greatly improves the completeness, accuracy, and early warning timeliness of temperature gradient evaluation.
[0042] Figure 3 This is a schematic flowchart illustrating a method for verifying and evaluating the reliability of bolt constraints on a back-end plate based on multi-dimensional test information during life cycle testing, as provided in one embodiment of this application. Further optimizations and extensions can be made based on the above technical solution, and it can be combined with the various optional implementation methods described above. For example... Figure 3 As shown, the method for verifying and evaluating the reliability of bolt constraints on the end plate during life cycles based on multi-dimensional test information may include the following steps:
[0043] S301. The power battery module under test and the vibration fixture are transferred to the vibration test bench to carry out the standard vibration test of the whole vehicle. The torque attenuation rate of the power battery module under test after vibration is collected through the standard vibration test of the whole vehicle.
[0044] In a specific embodiment of this application, the bolt constraint reliability verification and evaluation based on multi-dimensional test information may include the following steps: calculating the torque attenuation rate based on the collected initial assembly torque and residual torque after the test, and determining the bolt constraint reliability verification and evaluation based on the torque attenuation rate; wherein, the calculation formula for the torque attenuation rate is: Torque attenuation rate = (initial assembly standard torque - residual torque after the test) / initial assembly standard torque × 100%. This step is a pre-test stage for the final verification of module constraint reliability. The module under test, which has undergone a complete charge-discharge life cycle and has undergone expansion deformation, along with a vibration fixture that replicates the enclosure constraint at a 1:1 scale, is transferred to a vibration test bench. Durability vibration testing is carried out strictly in accordance with the vehicle vibration standard to simulate the combined harsh conditions of actual vehicle driving vibration and long-term cell expansion. After the vibration load is applied, the end plate bolt torque is detected and the torque attenuation rate is calculated to restore the torque loss of the bolts under the combined action of expansion force and vibration load during actual vehicle use, and to obtain constraint performance data that conforms to the actual working conditions of the vehicle.
[0045] S302. If the torque attenuation rate is less than or equal to the preset torque attenuation rate threshold, and the test power battery module does not exhibit bolt loosening, structural adhesive detachment, or relative module displacement after vibration, then the constraint structure of the test power battery module is deemed qualified.
[0046] This step completes the qualification judgment of the constraint structure by setting dual judgment criteria. It not only compares the bolt torque attenuation rate after the test with the preset design threshold, but also checks whether there are intuitive failure phenomena such as bolt loosening, structural adhesive detachment, and module slippage after vibration. The constraint structure is judged to be qualified only when both the numerical indicators and the appearance and structural condition meet the requirements. This avoids the one-sidedness of judging solely by the torque value and comprehensively verifies the overall ability of the module end plate, bottom bonding, and housing assembly constraint to resist the coupling effect of cell expansion and vehicle vibration.
[0047] The method for verifying and evaluating the reliability of endplate bolt constraints based on multi-dimensional test information during life cycle testing proposed in this application involves subjecting the module, which has undergone life expansion aging, along with vibration fixtures replicated from mass production assembly, to a standard vehicle vibration test. This simulates the harsh conditions of real vehicle vibration coupled with long-term cell expansion, and collects the bolt torque decay rate after vibration. This method can recreate the actual service stress environment of the battery pack and obtain constraint performance data that is more consistent with the vehicle's usage scenario. Furthermore, this application embodiment can also combine the quantitative index of torque decay rate with the appearance of bolts, structural adhesives, and module displacement to comprehensively determine whether the constraint structure is qualified. This avoids misjudgments caused by judging solely by torque values. The combination of these two methods can comprehensively verify the durability and reliability of the module constraint structure against the combined effects of cell expansion force and vehicle vibration, accurately identify defects in the endplate, adhesive, and assembly design, and improve the completeness and engineering authenticity of the constraint reliability evaluation.
[0048] Figure 4 This is a schematic diagram of the structure of an expansion evaluation device for a power battery module provided in an embodiment of this application. Figure 4 As shown, the expansion evaluation device for the power battery module includes: a data acquisition module 401, a verification and evaluation module 402, and a result determination module 403; wherein,
[0049] The data acquisition module 401 is used to synchronously acquire multi-dimensional test information of the power battery module under test throughout the entire life cycle of the power battery module under test.
[0050] The verification and evaluation module 402 is used to sequentially perform real-time temperature gradient comparison evaluation, module expansion displacement auxiliary evaluation, and life cycle rear plate bolt constraint reliability verification and evaluation based on the multi-dimensional test information.
[0051] The result judgment module 403 is used to comprehensively output the expansion judgment result of the power battery module under test based on the real-time comparison evaluation of the temperature gradient, the auxiliary evaluation of the module expansion displacement, and the reliability verification evaluation of the bolt constraint of the life cycle end plate.
[0052] The aforementioned expansion evaluation device for power battery modules can execute the method provided in any embodiment of this application, and has the corresponding functional modules and beneficial effects for executing the method. Technical details not described in detail in this embodiment can be found in the expansion evaluation method for power battery modules provided in any embodiment of this application.
[0053] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 5 A block diagram of an exemplary electronic device suitable for implementing embodiments of the present application is shown. Figure 5 The electronic device 12 shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.
[0054] like Figure 5 As shown, the electronic device 12 is represented in the form of a general-purpose computing device. The components of the electronic device 12 may include, but are not limited to: one or more processors or processing units 16, system memory 28, and bus 18 connecting different system components (including system memory 28 and processing unit 16).
[0055] Bus 18 represents one or more of several bus architectures, including a memory bus or memory controller, a peripheral bus, a graphics acceleration port, a processor, or a local bus using any of the various bus architectures. For example, these architectures include, but are not limited to, the Industry Standard Architecture (ISA) bus, the Micro Channel Architecture (MAC) bus, the Enhanced ISA bus, the Video Electronics Standards Association (VESA) local bus, and the Peripheral Component Interconnect (PCI) bus.
[0056] Electronic device 12 typically includes a variety of computer system readable media. These media can be any available media that can be accessed by electronic device 12, including volatile and non-volatile media, removable and non-removable media.
[0057] System memory 28 may include computer system readable media in the form of volatile memory, such as random access memory (RAM) 30 and / or cache memory 32. Electronic device 12 may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, storage system 34 may be used to read and write non-removable, non-volatile magnetic media (… Figure 5 Not shown; usually referred to as a "hard drive"). Although Figure 5As not shown, a disk drive for reading and writing to a removable non-volatile disk (e.g., a "floppy disk") and an optical disk drive for reading and writing to a removable non-volatile optical disk (e.g., a CD-ROM, DVD-ROM, or other optical media) may be provided. In these cases, each drive may be connected to bus 18 via one or more data media interfaces. Memory 28 may include at least one program product having a set (e.g., at least one) of program modules configured to perform the functions of the embodiments of this application.
[0058] A program / utility 40 having a set (at least one) of program modules 42 may be stored, for example, in memory 28. Such program modules 42 include, but are not limited to, an operating system, one or more application programs, other program modules, and program data. Each or some combination of these examples may include an implementation of a network environment. Program modules 42 typically perform the functions and / or methods described in the embodiments of this application.
[0059] Electronic device 12 can also communicate with one or more external devices 14 (e.g., keyboard, pointing device, display 24, etc.), and with one or more devices that enable a user to interact with electronic device 12, and / or with any device that enables electronic device 12 to communicate with one or more other computing devices (e.g., network card, modem, etc.). This communication can be performed via input / output (I / O) interface 22. Furthermore, electronic device 12 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public networks, such as the Internet) via network adapter 20. As shown, network adapter 20 communicates with other modules of electronic device 12 via bus 18. It should be understood that, although... Figure 5 As not shown, other hardware and / or software modules may be used in conjunction with electronic device 12, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.
[0060] The processing unit 16 executes various functional applications and data processing by running programs stored in the system memory 28, such as implementing the expansion evaluation method for the power battery module provided in the embodiments of this application.
[0061] This application also provides a computer storage medium.
[0062] The computer-readable storage medium of this application embodiment can be any combination of one or more computer-readable media. The computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. For example, a computer-readable storage medium can be—but is not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of computer-readable storage media (a non-exhaustive list) include: 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 or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium can be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.
[0063] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media may also be any computer-readable medium other than computer-readable storage media, capable of sending, propagating, or transmitting programs for use by or in connection with an instruction execution system, apparatus, or device.
[0064] Program code contained on a computer-readable medium may be transmitted using any suitable medium, including—but not limited to—wireless, wire, optical fiber, RF, etc., or any suitable combination thereof.
[0065] Computer program code for performing the operations of this application can be written in one or more programming languages or a combination thereof, including object-oriented programming languages such as Java, Smalltalk, and C++, and conventional procedural programming languages such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).
[0066] This application also provides a computer program product.
[0067] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer program products, which may include one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be an application-specific or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.
[0068] Note that the above are merely preferred embodiments and the technical principles employed in this application. Those skilled in the art will understand that this application is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of this application. Therefore, although this application has been described in detail through the above embodiments, this application is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of this application, the scope of which is determined by the scope of the appended claims.
Claims
1. A method for evaluating the expansion of a power battery module, characterized in that, The method includes: During the entire life cycle of the power battery module under test, multi-dimensional test information of the power battery module under test is collected simultaneously. Based on the multi-dimensional test information, the following tests are performed in sequence: real-time temperature gradient comparison evaluation, module expansion displacement auxiliary evaluation, and life cycle rear plate bolt constraint reliability verification evaluation. Based on the real-time temperature gradient comparison evaluation, the module expansion displacement auxiliary evaluation, and the life cycle rear plate bolt constraint reliability verification evaluation, the expansion determination result of the power battery module under test is comprehensively output.
2. The method according to claim 1, characterized in that, The multi-dimensional test information includes, but is not limited to: the expansion force distribution information of the end plate and cell contact surface of the power battery module under test, the instantaneous expansion displacement / cumulative displacement / residual deformation information of the two end plates of the power battery module under test, the surface temperature information of the main positive bolt / main positive end cell / main negative end cell / main negative bolt of the power battery module under test, and the cell temperature and single cell voltage reference information reported by the BMS of the power battery module under test.
3. The method according to claim 2, characterized in that, The surface temperature information includes at least: the maximum temperature NT1 of the main positive bolt of the power battery module under test, the maximum temperature NT2 of the first main positive cell of the power battery module under test, the maximum temperature NT3 of the first main negative cell of the power battery module under test, and the maximum temperature NT4 of the main negative bolt of the power battery module under test.
4. The method according to claim 1, characterized in that, Based on the aforementioned multi-dimensional test information, a real-time temperature gradient comparison and evaluation is performed, including: The externally independent measurement temperature and the BMS built-in measurement temperature are extracted in real time for the first charge-discharge lifetime cycle, the nth charge-discharge lifetime cycle in the middle period, and the ith charge-discharge lifetime cycle in the later period; where n and i are one of the charge-discharge lifetime cycles in the middle period and the later charge-discharge lifetime cycle, respectively. The measured temperatures of all temperature measurement points of the power battery module under test in the three cyclic stages are sorted from high to low. By comparing the degree of temperature change in the three cyclic stages, the risk level of copper busbar bolt loosening caused by cell expansion is determined according to the degree of change in the temperature gradient, and a real-time comparative evaluation of the temperature gradient is obtained.
5. The method according to claim 4, characterized in that, The risk level of copper busbar bolt loosening due to cell expansion is determined based on the degree of change in the sorting, including: If the temperature ranking in the first cycle is from high to low as follows: main positive bolt temperature, main negative bolt temperature, BMS temperature of the middle cell of the power battery module under test, main positive end cell temperature, and main negative end cell temperature; and the temperature ranking in the nth cycle is from high to low as follows: main negative bolt temperature, main positive bolt temperature, BMS temperature of the middle cell of the power battery module under test, main negative end cell temperature, and main positive end cell temperature, then it is determined that the power battery module under test has only a loosening deviation on one side of the connecting bolt, and the overall temperature distribution has not changed significantly, which is considered a low-risk condition. If the temperature ranking in the i-th cycle is from high to low as follows: main negative bolt temperature, main positive bolt temperature, main negative end cell temperature, BMS-collected temperature of the cell in the middle of the module, and main positive end cell temperature, then it is determined that the end cell temperature rise of the power battery module under test exceeds the normal range. If the FPC sampling line of the power battery module under test does not cover the temperature measurement point of the end cell, it is directly determined that there are design defects in the copper busbar connection structure and the cell expansion suppression structure.
6. The method according to claim 1, characterized in that, The bolt constraint reliability verification and evaluation are performed based on the multi-dimensional test information, including: The torque attenuation rate is calculated based on the initial assembly torque and the residual torque after the test, and the reliability verification and evaluation of the bolt constraint is determined according to the torque attenuation rate; wherein, the formula for calculating the torque attenuation rate is: torque attenuation rate = (initial assembly standard torque - residual torque after the test) / initial assembly standard torque × 100%.
7. The method according to claim 1, characterized in that, Based on the aforementioned multi-dimensional test information, a life cycle test is performed to verify and evaluate the reliability of the rear plate bolt constraints, including: The power battery module under test and the vibration fixture were transferred to the vibration test bench to carry out the standard vibration test of the whole vehicle. The torque attenuation rate of the power battery module under test after vibration was collected through the standard vibration test of the whole vehicle. If the torque attenuation rate is less than or equal to the preset torque attenuation rate threshold, and the power battery module under test does not exhibit bolt loosening, structural adhesive detachment, or relative displacement after vibration, then the constraint structure of the power battery module under test is deemed qualified.
8. An expansion evaluation device for a power battery module, characterized in that, The device includes: a data acquisition module, a verification and evaluation module, and a result determination module; wherein... The data acquisition module is used to synchronously collect multi-dimensional test information of the power battery module under test throughout the entire life cycle of the power battery module under test. The verification and evaluation module is used to perform real-time temperature gradient comparison evaluation, module expansion displacement auxiliary evaluation, and life cycle rear plate bolt constraint reliability verification and evaluation sequentially based on the multi-dimensional test information. The result judgment module is used to comprehensively output the expansion judgment result of the power battery module under test based on the real-time comparison evaluation of the temperature gradient, the auxiliary evaluation of the module expansion displacement, and the reliability verification evaluation of the bolt constraint of the life cycle end plate.
9. An electronic device, characterized in that, include: One or more processors; Memory, used to store one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement the expansion evaluation method for the power battery module as described in any one of claims 1 to 7.
10. A storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the expansion evaluation method for the power battery module as described in any one of claims 1 to 7.