Battery pack thermal runaway detection method, device, equipment and storage medium

Abstract

The present invention relates to the technical field of power batteries, and discloses a method, device, equipment and storage medium for detecting thermal runaway of a battery pack, the method comprising: obtaining the deformation amount of the battery pack to be tested after an extrusion test; matching the target deformation amount in a preset database according to the battery cell information of the battery pack to be tested; and detecting whether thermal runaway occurs in the battery pack to be tested according to the deformation amount and the target deformation amount. The present invention matches the target deformation amount in a preset database according to the battery cell information, and detects whether thermal runaway occurs in the battery pack to be tested according to the deformation amount and the target deformation amount after the extrusion test of the battery pack to be tested. It is possible to determine whether thermal runaway occurs in the battery pack to be tested by the deformation amount after the extrusion test and the target deformation amount matched in the preset database, thereby improving the accuracy of thermal runaway detection of the battery pack.

Description

Technical Field

[0001] The present invention relates to the field of power battery technology, and in particular to a battery pack thermal runaway detection method, device, equipment and storage medium. Background Art

[0002] At present, new energy vehicle technology is developing faster and faster, and new energy vehicles are becoming more and more popular. Thanks to the development of power battery technology, the charging speed and cruising range of new energy vehicles have also made great progress. However, when an accident occurs during the driving of a new energy vehicle, the power battery may be squeezed, causing thermal runaway of the power battery and causing a safety accident. Therefore, before the power battery is installed on the vehicle, it is necessary to detect whether it will experience thermal runaway under harsh working conditions such as squeezing and collision, so as to optimize the structure of the power battery when the structure does not meet the requirements. However, the accuracy of thermal runaway detection of battery packs in the existing technology is low, resulting in the inability to guarantee the safety of the power battery.

[0003] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

[0004] The main purpose of the present invention is to provide a battery pack thermal runaway detection method, device, equipment and storage medium, aiming to solve the technical problem of low accuracy in the prior art of detecting whether a power battery will experience thermal runaway.

[0005] To achieve the above object, the present invention provides a method for detecting thermal runaway of a battery pack, the method comprising the following steps:

[0006] Obtain the deformation amount of the battery pack to be tested after the extrusion test;

[0007] Matching the target deformation amount in a preset database according to the cell information of the battery pack to be tested;

[0008] Whether thermal runaway occurs in the battery pack to be tested is detected according to the deformation amount and the target deformation amount.

[0009] Optionally, before obtaining the deformation amount of the battery pack to be tested after the compression test, the method further includes:

[0010] Obtaining battery cell parameters during the extrusion test of multiple sample battery cells;

[0011] When the battery cell parameters meet the thermal runaway condition, obtaining the current deformation amount of the corresponding sample battery cell;

[0012] A preset database is constructed according to the cell information of the plurality of sample cells and the current deformation amount.

[0013] Optionally, constructing a preset database according to the cell information of the plurality of sample cells and the current deformation amount includes:

[0014] Determining the model of each sample battery cell according to the battery cell information of the multiple sample battery cells;

[0015] Determine the average deformation amount of sample cells of the same model according to the model and the current deformation amount;

[0016] A deformation variable threshold is determined according to the average deformation variable and a preset safety factor, and a preset database is constructed according to the deformation variable threshold and the model.

[0017] Optionally, the battery cell parameters include voltage drop, maximum temperature of a battery cell monitoring point, and temperature rise rate of a battery cell monitoring point;

[0018] When the battery cell parameter meets the thermal runaway condition, obtaining the current deformation amount of the corresponding sample battery cell includes:

[0019] Determining whether the temperature rise rate is greater than or equal to a preset rate;

[0020] If so, when the voltage drop is greater than a preset voltage drop and / or the maximum temperature is greater than a preset temperature, it is determined that the corresponding sample battery cell has thermal runaway;

[0021] When thermal runaway occurs in the sample battery cell, a current deformation amount of the sample battery cell is obtained.

[0022] Optionally, matching the target deformation amount in a preset database according to the cell information of the battery pack to be tested includes:

[0023] Determine the battery cell model according to the battery cell information of the battery pack to be tested;

[0024] The target shape amount is matched in a preset database according to the battery cell model.

[0025] Optionally, the detecting whether thermal runaway occurs in the battery pack to be tested according to the deformation amount and the target deformation amount includes:

[0026] Determining whether the deformation amount is greater than the target deformation amount;

[0027] If so, it is determined that thermal runaway occurs in the battery pack to be tested.

[0028] Optionally, after detecting whether thermal runaway occurs in the battery pack to be tested according to the deformation amount and the target deformation amount, the method further includes:

[0029] Obtaining an extrusion direction for performing an extrusion test on the battery pack to be tested;

[0030] The structure of the battery pack to be tested is optimized according to the extrusion direction.

[0031] In addition, to achieve the above-mentioned purpose, the present invention also proposes a battery pack thermal runaway detection device, the device comprising:

[0032] An acquisition module is used to obtain the deformation amount of the battery pack to be tested after the compression test;

[0033] A matching module, used for matching the target deformation amount in a preset database according to the cell information of the battery pack to be tested;

[0034] A detection module is used to detect whether thermal runaway occurs in the battery pack to be tested according to the deformation amount and the target deformation amount.

[0035] In addition, to achieve the above-mentioned purpose, the present invention also proposes a battery pack thermal runaway detection device, which includes: a memory, a processor, and a battery pack thermal runaway detection program stored in the memory and executable on the processor, and the battery pack thermal runaway detection program is configured to implement the steps of the battery pack thermal runaway detection method as described above.

[0036] In addition, to achieve the above-mentioned purpose, the present invention also proposes a storage medium, on which a battery pack thermal runaway detection program is stored. When the battery pack thermal runaway detection program is executed by a processor, the steps of the battery pack thermal runaway detection method described above are implemented.

[0037] The present invention obtains the deformation amount of the battery pack to be tested after the extrusion test; matches the target deformation amount in a preset database according to the battery cell information of the battery pack to be tested; and detects whether the battery pack to be tested has thermal runaway according to the deformation amount and the target deformation amount. The present invention matches the target deformation amount in a preset database according to the battery cell information, detects whether the battery pack to be tested has thermal runaway according to the deformation amount and the target deformation amount after the extrusion test of the battery pack to be tested, and can determine whether the battery pack to be tested has thermal runaway according to the deformation amount after the extrusion test and the target deformation amount matched in the preset database, thereby improving the accuracy of thermal runaway detection of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of a battery pack thermal runaway detection device in a hardware operating environment involved in an embodiment of the present invention;

[0039] Figure 2 It is a schematic diagram of the flow chart of the first embodiment of the battery pack thermal runaway detection method of the present invention;

[0040] Figure 3 It is a schematic flow chart of a second embodiment of a method for detecting thermal runaway of a battery pack according to the present invention;

[0041] Figure 4 A schematic diagram of a flow chart of a third embodiment of a method for detecting thermal runaway of a battery pack according to the present invention;

[0042] Figure 5 This is a structural block diagram of the first embodiment of the battery pack thermal runaway detection device of the present invention.

[0043] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0044] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0045] Reference Figure 1 , Figure 1 It is a schematic diagram of the structure of a battery pack thermal runaway detection device in the hardware operating environment involved in an embodiment of the present invention.

[0046] like Figure 1 As shown, the battery pack thermal runaway detection device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Among them, the communication bus 1002 is used to realize the connection and communication between these components. The user interface 1003 may include a display screen (Display), an input unit such as a keyboard (Keyboard), and the optional user interface 1003 may also include a standard wired interface and a wireless interface. The network interface 1004 may optionally include a standard wired interface and a wireless interface (such as a wireless fidelity (Wireless-Fidelity, WI-FI) interface). The memory 1005 may be a high-speed random access memory (Random Access Memory, RAM), or a stable non-volatile memory (Non-Volatile Memory, NVM), such as a disk storage. The memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0047] Those skilled in the art will understand that Figure 1 The structure shown in does not constitute a limitation on the battery pack thermal runaway detection device, and may include more or fewer components than shown in the figure, or a combination of certain components, or a different arrangement of components.

[0048] like Figure 1 As shown, the memory 1005 as a storage medium may include an operating system, a network communication module, a user interface module, and a battery pack thermal runaway detection program.

[0049] exist Figure 1In the battery pack thermal runaway detection device shown, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the battery pack thermal runaway detection device of the present invention can be set in the battery pack thermal runaway detection device, and the battery pack thermal runaway detection device calls the battery pack thermal runaway detection program stored in the memory 1005 through the processor 1001, and executes the battery pack thermal runaway detection method provided in the embodiment of the present invention.

[0050] The embodiment of the present invention provides a method for detecting thermal runaway of a battery pack, referring to Figure 2 , Figure 2 Schematic diagram of the process of the first embodiment of the battery pack thermal runaway detection method of the present invention.

[0051] In this embodiment, the battery pack thermal runaway detection method includes the following steps:

[0052] Step S10: Obtain the deformation amount of the battery pack to be tested after the compression test.

[0053] It should be noted that the execution subject of this embodiment can be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or an electronic device capable of realizing the above functions, a battery pack thermal runaway detection device, etc. The following takes the battery pack thermal runaway detection device (referred to as the detection device) as an example to illustrate this embodiment and the following embodiments.

[0054] In the present embodiment, simulation analysis software may be used to perform simulation analysis and detection on the model of the battery pack to be tested through the battery pack thermal runaway detection method of the present embodiment, so as to determine whether thermal runaway will occur in the battery pack to be tested under the existing structure, wherein the simulation analysis software may be CAE software; or the battery pack thermal runaway detection method of the present embodiment may be used to perform thermal runaway detection on the physical battery pack to be tested, which is not limited in the present embodiment.

[0055] It can be understood that the battery pack to be tested can be a battery pack that needs to be tested for thermal runaway; the extrusion test can be a test in which an external force is applied to the battery pack to be tested to cause the battery pack to be deformed, and the extrusion test simulates the external pressure on the battery pack in the event of an accident; the deformation amount can be the deformation amount of the battery cell in the battery pack to be tested after the extrusion test is completed, and the deformation amount can be the average of the deformation amounts of several target monitoring points on the battery cell, or it can be the deformation amount of a certain target monitoring point, and this embodiment is not limited here.

[0056] In a specific implementation, an extrusion test is performed on the battery pack to be tested to simulate the external pressure on the battery pack when an accident occurs to a new energy vehicle. After the extrusion test of the battery pack to be tested, a number of deformation variables corresponding to a number of target monitoring points on the battery cells in the battery pack are obtained, and the average of the several deformation variables is used as the deformation variable of the battery cells in the battery pack to be tested after the extrusion test.

[0057] Step S20: matching the target deformation amount in a preset database according to the cell information of the battery pack to be tested.

[0058] It can be understood that the cell information can be information that can represent the type of cell in the battery pack, and the cell information includes information such as the cell model, cell identification number and cell code; the preset database can be a pre-set database that stores the correspondence between the cell information and the cell deformation when the battery pack has thermal runaway; the target deformation variable can be the deformation variable corresponding to the cell information of the battery pack to be tested in the preset database, and the target deformation variable can be a threshold value. When the deformation variable of the cell in the corresponding type of battery pack does not reach the threshold value, it can be determined that the battery pack does not have thermal runaway; when the deformation variable of the cell in the corresponding type of battery pack reaches or exceeds the threshold value, it is determined that the battery pack has thermal runaway.

[0059] In a specific implementation, the target deformation amount of the battery cell when thermal runaway occurs in the battery pack of the type to be tested is matched in a preset database according to the battery cell information of the battery pack to be tested.

[0060] Step S30: detecting whether thermal runaway occurs in the battery pack to be tested according to the deformation amount and the target deformation amount.

[0061] In a specific implementation, an extrusion test is performed on the battery pack to be tested to simulate the external pressure on the battery pack when an accident occurs to a new energy vehicle. When the extrusion test of the battery pack to be tested is completed, a number of deformation variables corresponding to a number of target monitoring points on the battery cells in the battery pack to be tested are obtained, and the average of the several deformation variables is used as the deformation variable of the battery cells in the battery pack to be tested after the extrusion test of the battery pack to be tested. According to the battery cell information of the battery pack to be tested, the target deformation variable of the battery cell when thermal runaway occurs in the battery pack to be tested is matched in a preset database, and whether thermal runaway occurs in the battery pack to be tested is determined based on the relationship between the target deformation variable and the deformation variable.

[0062] Furthermore, in order to improve the accuracy of thermal runaway detection of the battery pack and improve the safety of the power battery, the step S20 includes: determining the battery cell model according to the battery cell information of the battery pack to be tested; and matching the target deformation amount in a preset database according to the battery cell model.

[0063] In a specific implementation, the cell model is read from the cell information of the battery pack to be tested, and the target deformation amount of the cell when thermal runaway occurs corresponding to the battery pack to be tested is matched in a preset database according to the cell model.

[0064] Furthermore, in order to improve the accuracy of thermal runaway detection of the battery pack and improve the safety of the power battery, the step S30 includes: determining whether the deformation amount is greater than the target deformation amount; if so, determining that thermal runaway occurs in the battery pack to be tested.

[0065] In a specific implementation, for example, the preset database may refer to Table 1, and the detection equipment performs an extrusion test on the battery pack to be tested. After the extrusion test, the deformation variables of the four target monitoring points on the battery cells are 3, 4, 4 and 5 respectively. The deformation variable of the battery cells in the battery pack to be tested is 4, and the battery cell model is determined to be A2 based on the battery cell information. The target deformation variable matched according to A2 in Table 1 is 2, and the deformation variable of the battery pack to be tested is greater than the target deformation variable. At this time, it is determined that thermal runaway occurs in the battery pack to be tested.

[0066] Table 1

[0067] Battery Model Deformation A1 3 A2 2 A3 5 A4 4

[0068] This embodiment obtains the deformation amount of the battery pack to be tested after the extrusion test; matches the target deformation amount in a preset database according to the battery cell information of the battery pack to be tested; and detects whether the battery pack to be tested has thermal runaway according to the deformation amount and the target deformation amount. This embodiment matches the target deformation amount in a preset database according to the battery cell information, and detects whether the battery pack to be tested has thermal runaway according to the deformation amount and the target deformation amount after the extrusion test of the battery pack to be tested. It is possible to determine whether the battery pack to be tested has thermal runaway according to the deformation amount after the extrusion test and the target deformation amount matched in the preset database, thereby improving the accuracy of thermal runaway detection of the battery pack.

[0069] refer to Figure 3 , Figure 3 Schematic diagram of the flow chart of the second embodiment of the battery pack thermal runaway detection method of the present invention.

[0070] Based on the first embodiment above, in this embodiment, before step S10, the method further includes:

[0071] Step S01: obtaining the cell parameters of multiple sample cells during the extrusion test.

[0072] It can be understood that the sample battery cell can be a battery cell that is not equipped with a protective structure for testing. On the other hand, a battery pack can be obtained after a protective structure is set for the sample battery cell. There are several models of sample batteries, and the number of batteries of each model is several. The battery cell parameters can be parameters for determining whether thermal runaway occurs in the battery cell. In the process of extrusion testing multiple sample batteries, the battery cell parameters of each sample battery cell are obtained.

[0073] Step S02: when the battery cell parameters meet the thermal runaway condition, obtaining the current deformation amount of the corresponding sample battery cell.

[0074] It can be understood that the thermal runaway condition can be a condition for determining whether thermal runaway occurs in a sample battery cell. The thermal runaway condition can specifically be a parameter threshold corresponding to the battery cell parameter. Whether the battery cell parameters meet the thermal runaway condition is determined based on the battery cell parameters and parameter threshold of the sample battery cell. The current deformation amount can be the deformation amount when thermal runaway occurs in the sample battery cell.

[0075] Step S03: constructing a preset database according to the cell information of the plurality of sample cells and the current deformation amount.

[0076] It should be understood that constructing a preset database based on the cell information of the multiple sample cells and the current deformation amount may be determining sample cells of the same type based on the cell information of the multiple sample cells, determining the average deformation amount of the sample cells of the same type based on the current deformation amount of each sample cell in the sample cells, and constructing a preset database based on the cell information corresponding to the average deformation amount of each type of sample cells.

[0077] In a specific implementation, a plurality of sample battery cells are subjected to an extrusion test, wherein the plurality of sample battery cells may be subjected to an extrusion test simultaneously or in a preset order. During the extrusion test on the sample battery cells, the battery cell parameters of each sample battery cell are obtained in real time, and whether thermal runaway occurs in the sample battery cell is determined based on the battery cell parameters and corresponding parameter thresholds. When thermal runaway occurs in the sample battery cell, the extrusion test on the corresponding sample battery cell is stopped, and the current deformation amount of the sample battery cell is obtained. When the extrusion test on all sample battery cells is completed, the current deformation amount of each sample battery cell when thermal runaway occurs is obtained, sample batteries of the same type are determined based on the battery cell information, the average deformation amount of sample batteries of the same type is calculated, and a preset database is constructed based on the average deformation amount and battery cell information of each battery cell of the same type.

[0078] Furthermore, in order to improve the accuracy of thermal runaway judgment of the sample battery cell, the battery cell parameters include voltage drop, the maximum temperature of the battery cell monitoring point and the temperature rise rate of the battery cell monitoring point, and the step S02 includes: judging whether the temperature rise rate is greater than or equal to a preset rate; if so, judging that the corresponding sample battery cell has thermal runaway when the voltage drop is greater than the preset voltage drop and / or the maximum temperature is greater than the preset temperature; and obtaining the current deformation amount of the sample battery cell when thermal runaway occurs to the sample battery cell.

[0079] It can be understood that the temperature rise rate can be the rate of temperature rise of the monitoring point on the sample battery cell; the maximum temperature can be the maximum temperature of the monitoring point on the sample battery cell; the voltage drop can be the voltage drop of the battery cell relative to the initial voltage during the extrusion test; the preset rate can be the maximum rate of temperature rise of the monitoring point on the sample battery cell when thermal runaway occurs in the preset sample battery cell; the preset voltage drop can be the voltage drop of the preset sample battery cell relative to the initial voltage when thermal runaway occurs; the preset temperature can be the temperature of the preset sample battery cell when thermal runaway occurs.

[0080] In a specific implementation, during the extrusion test of a sample battery cell, the temperature rise rate of a target monitoring point on the sample battery cell is obtained. If the temperature rise rate is greater than or equal to a preset rate, the decrease ratio of the voltage of the sample battery cell relative to the initial voltage is determined based on the voltage drop. When the decrease ratio is greater than a preset decrease ratio and / or the maximum temperature is greater than a preset temperature, it is determined that thermal runaway has occurred in the sample battery cell. When thermal runaway has occurred in the sample battery cell, the extrusion test of the sample battery cell is stopped and the current deformation amount is obtained.

[0081] Furthermore, in order to improve the accuracy of thermal runaway detection of the battery pack, the step S03 includes: determining the model of each sample battery cell based on the battery cell information of the multiple sample battery cells; determining the average deformation of the sample battery cells of the same model based on the model and the current deformation; determining the deformation threshold based on the average deformation and a preset safety factor, and constructing a preset database based on the deformation threshold and the model.

[0082] It can be understood that the preset safety factor may be a preset constant; determining the deformation variable threshold value according to the average deformation variable and the preset safety factor may be to obtain the deformation variable threshold value by dividing the average deformation variable by the preset safety factor.

[0083] In the specific implementation, it is assumed that there are three types of sample batteries, namely: A1, A2 and A3, and the preset safety factor is 1.5. The current deformation amount and average deformation amount corresponding to the sample batteries of each type can be referred to Table 2. According to Table 2, it can be determined that the deformation amount thresholds corresponding to A1, A2 and A3 are 2, 1.3 and 3.3 respectively. The preset database constructed according to the deformation amount threshold and model can be referred to Table 3.

[0084] Table 2

[0085]

[0086] Table 3

[0087] model Deformation A1 2 A2 1.3 A3 3.3

[0088] This embodiment obtains the cell parameters of multiple sample cells during the extrusion test; when the cell parameters meet the thermal runaway conditions, the current deformation of the corresponding sample cells is obtained; and a preset database is constructed based on the cell information of the multiple sample cells and the current deformation. This embodiment obtains the cell parameters during the extrusion test of multiple sample cells, and when the cell parameters meet the thermal runaway conditions, a preset database is constructed based on the current deformation and cell information of the sample cells, so as to determine whether the battery pack to be tested has thermal runaway according to the preset database, thereby improving the accuracy of thermal runaway detection of the battery pack.

[0089] refer to Figure 4 , Figure 4 Schematic diagram of the flow chart of the third embodiment of the battery pack thermal runaway detection method of the present invention.

[0090] Based on the above embodiments, in this embodiment, after step S30, the method further includes:

[0091] Step S40: obtaining the squeezing direction of the squeezing test on the battery pack to be tested.

[0092] It can be understood that the extrusion direction includes lateral extrusion and longitudinal extrusion. The extrusion direction for the extrusion test on the battery pack to be tested can be obtained by obtaining the extrusion control parameters when the extrusion test is performed on the battery pack to be tested, and the extrusion direction of the battery pack to be tested is determined according to the extrusion control parameters.

[0093] Step S50: optimizing the structure of the battery pack to be tested according to the extrusion direction.

[0094] It can be understood that the structural optimization of the battery pack to be tested according to the extrusion direction may be to determine the extrusion direction when the battery pack to be tested has thermal runaway, and to optimize the structure of the battery pack to be tested in the corresponding direction according to the extrusion direction.

[0095] In a specific implementation, when performing an extrusion test on the battery pack to be tested, the extrusion direction of the battery pack to be tested is determined to be lateral extrusion according to the extrusion control parameters, and the structural optimization method of the battery pack to be tested can be to add a crossbeam in the lateral direction of the battery pack to improve the lateral strength of the battery pack.

[0096] Furthermore, in order to optimize the structure of the battery pack according to the detection results to improve the safety of the battery pack when thermal runaway occurs in the battery pack, the step S50 includes: determining the direction of the battery pack that is the same as the extrusion direction as the structural optimization direction; determining the strength to be improved according to the deformation amount; and setting a reinforcement structure for the battery pack of the same model as the battery pack to be tested according to the structural optimization direction and the strength to be improved.

[0097] In the specific implementation, assuming that the extrusion direction is longitudinal extrusion, the structural optimization direction is longitudinal optimization, and the structural strength that offsets the deformation is set as the strength to be improved. The corresponding reinforcement structure is selected according to the strength to be improved. The reinforcement structure can be aluminum alloy, iron or other metals, and the reinforcement structure is set in the longitudinal direction of the battery pack to improve the strength of the battery pack.

[0098] This embodiment obtains the extrusion direction of the battery pack to be tested for extrusion testing, and optimizes the structure of the battery pack to be tested according to the extrusion direction. This embodiment can optimize the structure of the battery pack according to the extrusion direction, thereby improving the development efficiency of the battery pack structure.

[0099] In addition, an embodiment of the present invention further proposes a storage medium, on which a battery pack thermal runaway detection program is stored. When the battery pack thermal runaway detection program is executed by a processor, the steps of the battery pack thermal runaway detection method as described above are implemented.

[0100] Reference Figure 5 , Figure 5 This is a structural block diagram of the first embodiment of the battery pack thermal runaway detection device of the present invention.

[0101] like Figure 5 As shown, the battery pack thermal runaway detection device proposed in the embodiment of the present invention includes:

[0102] An acquisition module 10 is used to obtain the deformation amount of the battery pack to be tested after the compression test;

[0103] A matching module 20, configured to match a target deformation amount in a preset database according to the cell information of the battery pack to be tested;

[0104] The detection module 30 is used to detect whether thermal runaway occurs in the battery pack to be tested according to the deformation amount and the target deformation amount.

[0105] This embodiment obtains the deformation amount of the battery pack to be tested after the extrusion test; matches the target deformation amount in a preset database according to the battery cell information of the battery pack to be tested; and detects whether the battery pack to be tested has thermal runaway according to the deformation amount and the target deformation amount. This embodiment matches the target deformation amount in a preset database according to the battery cell information, and detects whether the battery pack to be tested has thermal runaway according to the deformation amount and the target deformation amount after the extrusion test of the battery pack to be tested. It is possible to determine whether the battery pack to be tested has thermal runaway according to the deformation amount after the extrusion test and the target deformation amount matched in the preset database, thereby improving the accuracy of thermal runaway detection of the battery pack.

[0106] Based on the above-mentioned first embodiment of the battery pack thermal runaway detection device of the present invention, a second embodiment of the battery pack thermal runaway detection device of the present invention is proposed.

[0107] In this embodiment, the acquisition module 10 is also used to obtain the cell parameters of multiple sample cells during the extrusion test; when the cell parameters meet the thermal runaway conditions, obtain the current deformation of the corresponding sample cells; and build a preset database based on the cell information of the multiple sample cells and the current deformation.

[0108] The acquisition module 10 is also used to determine the model of each sample battery cell based on the battery cell information of the multiple sample battery cells; determine the average deformation of the sample battery cells of the same model based on the model and the current deformation; determine the deformation threshold based on the average deformation and a preset safety factor, and build a preset database based on the deformation threshold and the model.

[0109] The acquisition module 10 is also used to determine whether the temperature rise rate is greater than or equal to a preset rate; if so, when the voltage drop is greater than the preset voltage drop and / or the maximum temperature is greater than the preset temperature, it is determined that the corresponding sample battery cell has thermal runaway; when the sample battery cell has thermal runaway, the current deformation of the sample battery cell is acquired; the battery cell parameters include the voltage drop, the maximum temperature of the battery cell monitoring point and the temperature rise rate of the battery cell monitoring point.

[0110] The matching module 20 is further used to determine the battery cell model according to the battery cell information of the battery pack to be tested; and match the target deformation amount in a preset database according to the battery cell model.

[0111] The detection module 30 is further used to determine whether the deformation amount is greater than the target deformation amount; if so, it is determined that thermal runaway occurs in the battery pack to be tested.

[0112] The detection module 30 is further used to obtain an extrusion direction of the battery pack to be tested for an extrusion test; and perform structural optimization on the battery pack to be tested according to the extrusion direction.

[0113] Other embodiments or specific implementations of the battery pack thermal runaway detection device of the present invention can refer to the above-mentioned method embodiments and will not be described in detail here.

[0114] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0115] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0116] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as a read-only memory / random access memory, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present invention.

[0117] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for detecting thermal runaway of a battery pack, It is characterized in that The method comprises: Obtaining the deformation amount of the battery pack to be tested after the extrusion test, wherein the deformation amount is the average value of the deformation amounts of several target monitoring points on the battery cell; Matching the target deformation amount in a preset database according to the cell information of the battery pack to be tested; Detecting whether thermal runaway occurs in the battery pack to be tested according to the deformation amount and the target deformation amount; Before obtaining the deformation amount of the battery pack to be tested after the compression test, the method further includes: Obtaining battery cell parameters during the extrusion test of multiple sample battery cells; When the battery cell parameters meet the thermal runaway condition, obtaining the current deformation amount of the corresponding sample battery cell; Determining the model of each sample battery cell according to the battery cell information of the multiple sample battery cells; Determine the average deformation amount of sample cells of the same model according to the model and the current deformation amount; Determine a deformation variable threshold value according to the average deformation variable and a preset safety factor, and construct a preset database according to the deformation variable threshold value and the model; After detecting whether thermal runaway occurs in the battery pack to be tested according to the deformation amount and the target deformation amount, the method further includes: Acquire an extrusion direction of an extrusion test on the battery pack to be tested, wherein the extrusion direction includes a lateral extrusion and a longitudinal extrusion; Performing structural optimization on the battery pack to be tested according to the extrusion direction; The obtaining of the squeezing direction of the squeezing test on the battery pack to be tested includes: When performing an extrusion test on the battery pack to be tested, obtaining extrusion control parameters; Determining an extrusion direction of the battery pack to be tested according to the extrusion control parameter; The structural optimization of the battery pack to be tested according to the extrusion direction includes: Determine the direction of the battery pack that is the same as the extrusion direction as the structural optimization direction; Determining the strength to be increased according to the deformation amount; According to the structural optimization direction and the strength to be improved, a reinforcement structure is provided for the battery pack to be tested; The step of providing a reinforcement structure for the battery pack to be tested according to the structural optimization direction and the strength to be improved includes: If the extrusion direction is lateral extrusion, the structural optimization direction is determined to be lateral optimization, and a crossbeam is added in the lateral direction of the battery pack to be tested; If the extrusion direction is longitudinal extrusion, the structural optimization direction is determined to be longitudinal optimization, and the structural strength that offsets the deformation is set as the strength to be improved. The corresponding reinforcement structure is selected according to the strength to be improved, and the reinforcement structure is arranged in the longitudinal direction of the battery pack to be tested.

2. The method according to claim 1, It is characterized in that The battery cell parameters include voltage drop, maximum temperature of the battery cell monitoring point and temperature rise rate of the battery cell monitoring point; When the battery cell parameter meets the thermal runaway condition, obtaining the current deformation amount of the corresponding sample battery cell includes: Determining whether the temperature rise rate is greater than or equal to a preset rate; If so, when the voltage drop is greater than a preset voltage drop and / or the maximum temperature is greater than a preset temperature, it is determined that the corresponding sample battery cell has thermal runaway; When thermal runaway occurs in the sample battery cell, a current deformation amount of the sample battery cell is obtained.

3. The method according to claim 1, It is characterized in that The step of matching the target deformation amount in a preset database according to the cell information of the battery pack to be tested comprises: Determine the battery cell model according to the battery cell information of the battery pack to be tested; The target shape amount is matched in a preset database according to the battery cell model.

4. The method according to claim 3, It is characterized in that The detecting whether thermal runaway occurs in the battery pack to be tested according to the deformation amount and the target deformation amount includes: Determining whether the deformation amount is greater than the target deformation amount; If so, it is determined that thermal runaway occurs in the battery pack to be tested.

5. A battery pack thermal runaway detection device, It is characterized in that The device comprises: An acquisition module is used to obtain the deformation of the battery pack to be tested after the extrusion test, wherein the deformation is the average of the deformations of several target monitoring points on the battery cell; A matching module, used for matching the target deformation amount in a preset database according to the cell information of the battery pack to be tested; A detection module, used for detecting whether thermal runaway occurs in the battery pack to be tested according to the deformation amount and the target deformation amount; The acquisition module is further used to acquire the battery cell parameters of multiple sample battery cells during the extrusion test; when the battery cell parameters meet the thermal runaway conditions, acquire the current deformation amount of the corresponding sample battery cell; determine the model of each sample battery cell according to the battery cell information of the multiple sample battery cells; determine the average deformation amount of the sample battery cells of the same model according to the model and the current deformation amount; determine the deformation amount threshold value according to the average deformation amount and the preset safety factor, and build a preset database according to the deformation amount threshold value and the model; The detection module is further used to obtain an extrusion direction of the battery pack to be tested for an extrusion test, wherein the extrusion direction includes a transverse extrusion and a longitudinal extrusion; and perform structural optimization on the battery pack to be tested according to the extrusion direction; The detection module is further used to obtain an extrusion control parameter when performing an extrusion test on the battery pack to be tested; and determine an extrusion direction of the battery pack to be tested according to the extrusion control parameter; The detection module is further used to determine that the direction of the battery pack that is the same as the extrusion direction is a structural optimization direction; determine the strength to be improved according to the deformation amount; and set a reinforcement structure for the battery pack to be tested according to the structural optimization direction and the strength to be improved; The detection module is also used to determine that the structural optimization direction is lateral optimization if the extrusion direction is lateral extrusion, and add a crossbeam in the lateral direction of the battery pack to be tested; if the extrusion direction is longitudinal extrusion, determine that the structural optimization direction is longitudinal optimization, and set the structural strength that offsets the deformation amount as the strength to be improved, select the corresponding reinforcement structure according to the strength to be improved, and set the reinforcement structure in the longitudinal direction of the battery pack to be tested.

6. A battery pack thermal runaway detection device, It is characterized in that The device includes: a memory, a processor, and a battery pack thermal runaway detection program stored in the memory and executable on the processor, wherein the battery pack thermal runaway detection program is configured to implement the steps of the battery pack thermal runaway detection method as described in any one of claims 1 to 4.

7. A storage medium, It is characterized in that The storage medium stores a battery pack thermal runaway detection program, which, when executed by a processor, implements the steps of the battery pack thermal runaway detection method according to any one of claims 1 to 4.

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