A method, apparatus, and storage medium for simulating a battery mechanical impact test

Abstract

A simulation method of battery mechanical impact test, comprising: respectively performing tensile test on a sample of a preset positive plate, a sample of a preset negative plate, a sample of a preset separator and a sample of a preset shell to obtain corresponding mechanical data; and / or, respectively performing compression test to obtain corresponding mechanical data; constructing a battery model according to the corresponding material parameters and mechanical data of the preset positive plate, the preset negative plate, the preset separator and the preset shell; constructing an impact process model according to a preset impact condition, and using the impact process model to perform impact simulation test on the battery model corresponding to the preset battery to obtain a simulation test result, which includes energy data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell. The impact simulation test of the battery model by the impact process model makes the energy change of the preset positive plate, the preset negative plate, the preset separator and the preset shell in the impact process quantifiable.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a battery mechanical impact test simulation method, device and storage medium. BACKGROUND

[0002] Lithium ion battery as a high energy density energy storage battery is widely used in various electric tools, electric vehicles and various portable devices. However, lithium ion battery also has some safety problems, such as thermal runaway of lithium ion battery caused by mechanical abuse. At this time, the deformation of lithium ion battery will cause the damage of the structure such as pole piece and diaphragm in the battery, and then cause internal short circuit. At present, the evaluation method of such safety risk of battery is: heavy impact method, extrusion method, that is, the battery is measured by heavy impact method or extrusion method. However, these evaluation methods have hysteresis.

[0003] Thermal runaway of lithium ion battery caused by mechanical abuse is usually accompanied by energy change, but the energy change cannot be quantified, so how to quantify the energy generated in the thermal runaway of battery is a technical problem to be solved. SUMMARY

[0004] The technical problem solved by the present application is to quantify the energy generated in the thermal runaway of battery.

[0005] According to the first aspect, in one embodiment, a battery mechanical impact test simulation method is provided, a preset battery includes a plurality of preset positive pole pieces, a plurality of preset negative pole pieces, a plurality of preset diaphragms and a preset shell, the method comprises:

[0006] Respectively, the sample of the preset positive pole piece, the sample of the preset negative pole piece, the sample of the preset diaphragm and the sample of the preset shell are subjected to tensile test to obtain corresponding mechanical data; and / or, the sample of the preset positive pole piece, the sample of the preset negative pole piece, the sample of the preset diaphragm and the sample of the preset shell are subjected to compression test to obtain corresponding mechanical data;

[0007] According to the material parameters and mechanical data corresponding to the preset positive pole piece, the preset negative pole piece, the preset diaphragm and the preset shell, a battery model corresponding to the preset battery is constructed;

[0008] According to the preset impact condition, an impact process model is constructed, and the impact process model is used to perform impact simulation test on the battery model corresponding to the preset battery to obtain simulation test results, the simulation test results include energy data corresponding to the preset positive pole piece, the preset negative pole piece, the preset diaphragm and the preset shell.

[0009] According to a second aspect, an embodiment provides a simulation device for mechanical impact test of a battery, the device comprising:

[0010] a obtaining unit configured to obtain mechanical data of a preset positive plate, a preset negative plate, a preset separator and a preset shell, wherein the mechanical data of the preset positive plate, the preset negative plate, the preset separator and the preset shell are obtained by performing tensile test and / or compression test on a sample of the preset positive plate, a sample of the preset negative plate, a sample of the preset separator and a sample of the preset shell respectively;

[0011] a constructing unit configured to construct a battery model corresponding to a preset battery according to material parameters and mechanical data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell, and to construct an impact process model according to a preset impact condition, and to perform impact simulation test on the battery model corresponding to the preset battery by using the impact process model, to obtain a simulation test result, wherein the simulation test result comprises energy data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell, and wherein the energy data is used to provide a reference for design of the preset battery.

[0012] According to a third aspect, an embodiment provides a computer readable storage medium comprising a program, which can be executed by a processor to implement the method described above.

[0013] According to a fourth aspect, an embodiment provides a computer program product comprising a computer program and / or instructions, which, when executed by a processor, implement the method described above.

[0014] According to the simulation method for mechanical impact test of a battery described above, by inputting material parameters and mechanical data corresponding to a preset positive plate, a preset negative plate, a preset separator and a preset shell into a preset model software, a battery model corresponding to a preset battery is constructed, and an impact process model is constructed according to a preset impact condition, and after impact simulation test on the battery model by using the impact process model, energy data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell can be obtained, thereby realizing quantification of energy change of the preset positive plate, the preset negative plate, the preset separator and the preset shell in an impact process, and providing a reference for design of the preset battery. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 A flowchart of a simulation method for mechanical impact test of a battery provided by the embodiment;

[0016] Figure 2 A schematic diagram of a battery cell of a lithium ion battery A after impact test provided by the embodiment;

[0017] Figure 3 A schematic diagram of another cell of the lithium ion battery B provided in this embodiment after impact test;

[0018] Figure 4 A schematic diagram of a cell of the lithium ion battery B provided in this embodiment after impact test;

[0019] Figure 5 A schematic diagram of another cell of the lithium ion battery B provided in this embodiment after impact test;

[0020] Figure 6 A structural block diagram of a simulation device for battery mechanical impact test provided in this embodiment. DETAILED DESCRIPTION

[0021] The application will be further described in details through specific embodiments and the accompanying drawings. In different embodiments, similar elements are associated with similar element labels. In the following embodiments, many details are described in order to make the application better understood. However, those skilled in the art can easily recognize that some features can be omitted in different cases, or can be replaced by other elements, materials, methods. In some cases, some operations related to the application are not shown or described in the specification, in order to avoid the core part of the application being overwhelmed by too much description, and it is not necessary to describe these related operations in detail for those skilled in the art according to the description in the specification and general technical knowledge in the art.

[0022] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate way to form various embodiments. At the same time, the steps or actions in the method description can also be sequentially adjusted or adjusted in a manner that is obvious to those skilled in the art. Therefore, the order in the specification and the drawings is only for the purpose of clearly describing a certain embodiment, and does not mean that it is the necessary order, unless otherwise stated that a certain order must be followed.

[0023] The serial numbers of the components in this paper, such as "first", "second", etc., are only used to distinguish the described objects, and do not have any order or technical meaning. Unless otherwise specified, "connection" and "coupling" in this application include direct and indirect connections (couplings).

[0024] The following is the definition of the battery structure:

[0025] 1. Positive active layer

[0026] The positive active layer is a key part of the lithium ion battery cathode, mainly composed of active material, conductive agent and binder. These materials are coated on the surface of the positive current collector to form a porous composite layer. The main function of the positive active layer is to store and release lithium ions, which is the main place for the battery to carry out electrochemical reactions. During charging, lithium ions are embedded into the material of the positive active layer from the electrolyte; during discharging, lithium ions are removed from the positive active layer into the electrolyte, completing the transfer of electric charge.

[0027] 2、Negative active layer

[0028] The negative active layer is similar to the positive active layer, also composed of active material, conductive agent and binder, coated on the surface of the negative current collector. The main function of the negative active layer is to receive and store lithium ions migrated from the positive electrode. During charging, lithium ions are embedded into the material of the negative active layer from the electrolyte; during discharging, lithium ions are removed from the negative active layer back to the electrolyte, completing the transfer of electric charge.

[0029] 3、Positive current collector

[0030] The positive current collector is a component of the lithium ion battery cathode. Its main function is to carry the positive active layer and collect the current generated by the active layer for output. During the charging and discharging process of the battery, the positive current collector provides a transmission channel for electrons, accelerates the transfer of electric charge, reduces the polarization phenomenon in the electrochemical reaction, and improves the charging and discharging efficiency of the battery.

[0031] 4、Negative current collector

[0032] The negative current collector is a component of the lithium ion battery anode. Its function is similar to that of the positive current collector, mainly to carry the negative active layer and collect the current generated by the active layer for output. During the charging and discharging process of the battery, the negative current collector also provides a transmission channel for electrons, accelerating the transfer of electric charge.

[0033] Currently, lithium ion batteries have the following safety problems: thermal runaway of lithium ion batteries caused by mechanical abuse. Deformation of lithium ion batteries can cause damage to the internal structure of the cell, such as the pole piece and the diaphragm, and then cause internal short circuit. Currently, the way to evaluate the safety risk of the battery is: heavy impact method, extrusion method, that is, by heavy impact method or extrusion method to measure the cell, but these evaluation methods have lag. The thermal runaway of lithium ion batteries caused by mechanical abuse is usually accompanied by energy changes, but these energy changes cannot be quantified.

[0034] Based on this, the scheme of the present application is proposed. In the embodiment of the present application, the material parameters and mechanical data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell are input into the preset model software to construct a battery model corresponding to the preset battery; and an impact process model is constructed according to the preset impact condition; after the impact process model is used to simulate and test the battery model, the energy data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell can be obtained, thereby realizing the quantification of the energy change of the preset positive plate, the preset negative plate, the preset separator and the preset shell in the impact process, and providing a reference for the design of the preset battery. The following embodiments will be described in detail.

[0035] Embodiment one, please refer to Figure 1 , Figure 1 is a flowchart of a simulation method for battery mechanical impact test provided by the present embodiment, as Figure 1 shown, the method specifically includes the following steps 101-103:

[0036] Step 101, respectively, the sample of the preset positive plate, the sample of the preset negative plate, the sample of the preset separator and the sample of the preset shell are tested by stretching to obtain the corresponding mechanical data; and / or, respectively, the sample of the preset positive plate, the sample of the preset negative plate, the sample of the preset separator and the sample of the preset shell are tested by compression to obtain the corresponding mechanical data.

[0037] Here, the plurality of preset positive plates and the plurality of preset negative plates belong to the plate group of the preset battery. The preset battery can be any type of battery. Exemplarily, the preset battery can be a lithium ion battery, and can also be a nickel-chromium battery, which is not limited by the present application.

[0038] The following are described by taking a lithium ion battery as an example. The preset battery can be a battery in the design stage, that is, the specifications of the preset positive plate, the preset negative plate, the preset separator and the preset shell are known. It should be noted that the sample of the positive plate can be produced according to the design parameters of the positive plate; the sample of the negative plate can be produced according to the design parameters of the negative plate; the sample of the preset separator can be produced according to the design parameters of the separator; and the sample of the preset shell can be produced according to the design parameters of the shell.

[0039] In practical applications, the sample for tensile testing and the sample for compression testing are the same, which specifically includes the following contents:

[0040] Metallic materials (shell, current collector): The physical and chemical properties of metallic materials are nearly identical in all directions. That is, the physical and chemical properties of metallic materials are nearly the same in the transverse and longitudinal directions. In actual measurement, it is possible to select one direction (transverse or longitudinal) to measure the mechanical data. When fabricating the metallic shell structural component (a pre-designed shell sample), it can be made into any shape; for example, it can be made into an "I"-shaped sample. Similarly, when fabricating the current collector structural component, it can be made into any shape; for example, it can be made into a long strip-shaped sample.

[0041] Plastic materials (diaphragms): The physical and chemical properties of plastic materials differ in all directions. That is, the physical and chemical properties of plastic materials differ between the transverse and longitudinal directions. In actual measurement, it is necessary to measure not only the transverse mechanical data but also the longitudinal mechanical data of the plastic materials. When manufacturing plastic structural components (pre-set diaphragms), they can be made into samples of any shape; for example, the plastic structural component can be made into a rectangular sample.

[0042] Positive and negative electrode plates: The physical and chemical properties of the positive electrode plate are nearly identical in all directions. That is, the physical and chemical properties of the positive electrode plate are nearly identical in the transverse and longitudinal directions. In actual measurement, only one direction (transverse or longitudinal) of mechanical data needs to be measured. When manufacturing the positive electrode plate structure (a pre-designed positive electrode plate sample), it can be made into any shape; for example, it can be made into a rectangular sample. Similarly, the physical and chemical properties of the negative electrode plate are nearly identical in all directions. That is, the physical and chemical properties of the negative electrode plate are nearly identical in the transverse and longitudinal directions. In actual measurement, only one direction (transverse or longitudinal) of mechanical data needs to be measured. When manufacturing the negative electrode plate structure (a pre-designed negative electrode plate sample), it can be made into any shape; for example, it can be made into a rectangular sample.

[0043] It should be noted that both the positive electrode structure and the negative electrode structure can be made into circular samples.

[0044] In practical applications, the number of positive electrode samples and the number of negative electrode samples can be any number. For example, the number of positive electrode samples can be 25, and the number of negative electrode samples can also be 25.

[0045] It should be noted that the tensile force in the tensile test can be any value; the tensile speed can be any value.

[0046] In practical applications, the tensile test standard in the national standard can be selected, and a tensile tester or a device with a tensile function can be used to perform a tensile test on the preset battery to obtain mechanical data such as tensile strength, elongation at break, and elastic modulus. The tensile force corresponding to the tensile test standard can be any value of tensile force. For example, the tensile force can be 1 KN. The tensile speed corresponding to the tensile test standard can be any value of tensile speed. For example, the tensile speed can be 250 mm / min.

[0047] Here, the mechanical data obtained by the tensile test at least includes one of the following: tensile strength, elongation at break, and elastic modulus.

[0048] It should be noted that the tensile strength can represent the maximum uniform plastic deformation stress that the sample of the preset positive plate, the sample of the preset negative plate, the sample of the preset separator, and the sample of the preset shell can withstand during the stretching process.

[0049] It should be noted that the elongation at break can represent the ratio of the elongation length after stretching to the length before stretching when the sample of the preset positive plate, the sample of the preset negative plate, the sample of the preset separator, and the sample of the preset shell are subjected to an external force to be pulled apart.

[0050] It should be noted that the elastic modulus can be used to measure the size of the resistance of the sample of the preset positive plate, the sample of the preset negative plate, the sample of the preset separator, and the sample of the preset shell to elastic deformation.

[0051] It should be noted that the compression force in the compression test can be any value of compression force; the compression speed can be any value of compression speed.

[0052] In practical applications, the compression test standard in the national standard can be selected, and an extrusion tester, a compression tester, or a device with a compression function can be used to perform a compression test on the preset battery to obtain data such as compression deformation and compression rate. The compression force corresponding to the compression test standard can be any value of compression force. For example, the compression force can be 1.3 KN. The compression speed corresponding to the compression test standard can be any value of compression speed. For example, the compression speed can be 0.1 mm / min.

[0053] Here, the mechanical data obtained by the compression test at least includes one of the following: compression deformation and compression rate.

[0054] It should be noted that the compression deformation can represent the deformation of the sample of the preset positive plate, the sample of the preset negative plate, the sample of the preset separator, and the sample of the preset shell along the compression direction (usually the radial or height direction) when subjected to a compression force.

[0055] It should be noted that the compression rate can represent the ratio of the deformation amount to the original size of the sample of the preset positive plate, the sample of the preset negative plate, the sample of the preset diaphragm and the sample of the preset shell when subjected to the compression force.

[0056] In step 102, according to the material parameters and mechanical data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell, a battery model corresponding to the preset battery is constructed.

[0057] Here, when constructing the battery model corresponding to the preset battery, the mechanical data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell can be homogenized to obtain homogenized mechanical data; the material parameters and the homogenized mechanical data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell are input into the preset model software to construct a first battery model corresponding to the preset battery.

[0058] It should be noted that the preset model software can be any simulation software, for example, the preset model software can be Abaqus engineering simulation software or ANSYS general finite element analysis software. In this regard, the present application does not make any limitation.

[0059] It should be noted that the mechanical data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell is homogenized, that is, without considering the difference between the mechanical data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell, the homogenized mechanical data and the obtained material parameters are used to construct a simple battery model, that is, the first battery model.

[0060] In practical applications, the first battery model corresponding to the preset battery has a small number of grids, which can be calculated quickly to improve the calculation efficiency.

[0061] Here, when constructing the battery model corresponding to the preset battery, the material parameters and the mechanical data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell can also be input into the preset model software to construct a second battery model corresponding to the preset battery.

[0062] It should be noted that in practical applications, the mechanical data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell can have differences. The mechanical data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell with differences and the material parameters are input into the preset model software, which can construct a second battery model different from the first battery model.

[0063] It should be noted that the second battery model corresponding to the preset battery has a larger number of grids than the first battery model corresponding to the preset battery, which requires more computer hardware and has higher accuracy of the calculation result than the first battery model.

[0064] It should be noted that the material parameter corresponding to the preset positive plate can be any parameter. For example, the material parameter corresponding to the preset positive plate can be lithium cobaltate, nickel-cobalt-manganese ternary material, lithium manganate, iron lithium phosphate or lithium metal. The material parameter corresponding to the preset negative plate can be any parameter. For example, the material parameter corresponding to the preset negative plate can be graphite, silicon-based material, metal oxide or metal sulfide. The material parameter corresponding to the preset separator can be any parameter. For example, the material parameter corresponding to the preset separator can be polyolefin material, non-woven fabric film, microporous film, composite film or modified microporous film. The material parameter corresponding to the preset shell can be any parameter. For example, the material parameter corresponding to the preset shell can be aluminum alloy or steel.

[0065] In step 103, a shock process model is constructed according to the preset shock condition, and the preset battery corresponding to the battery model is simulated and tested by using the shock process model, to obtain a simulation test result. The simulation test result includes energy data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell.

[0066] It should be noted that when the shock process model is constructed according to the preset shock condition, the preset shock condition can be input into a simulation software, so as to construct the shock process model. Here, the simulation software can be any software. For example, the simulation software can be Abaqus engineering simulation software or ANSYS general finite element analysis software. In this regard, the present application does not make any limitation.

[0067] It should be noted that the preset battery corresponding to the battery model is simulated and tested by using the shock process model, to obtain energy data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell. That is, the preset battery corresponding to the battery model is simulated and tested according to the preset shock condition, and the energy absorbed by the preset positive plate, the preset negative plate, the preset separator and the preset shell in the shock process is quantified, so as to reasonably design the preset battery according to the energy data.

[0068] Here, the preset shock condition includes a preset shock speed, a preset shock angle and a preset shock force.

[0069] In actual application, the preset shock speed can be any value of shock speed; the preset shock angle can be any value of shock angle; and the preset shock force can be any value of shock force. In this regard, the present application does not make any limitation.

[0070] Here, the preset battery is designed according to the energy data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell, to obtain a target battery.

[0071] Herein, when designing the preset battery to obtain the target battery, the energy distribution corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell can be determined based on the energy data; when the energy distribution does not meet the design requirement, the design parameter of at least one of the preset positive plate, the preset negative plate, the preset separator and / or the preset shell is adjusted according to the energy distribution to obtain the target battery; wherein the design parameter comprises at least one of a material parameter, a structure parameter and a preset number.

[0072] It should be noted that the purpose of determining the energy distribution corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell based on the energy data is to determine whether the energy distribution corresponding to the preset battery meets the design requirement according to the energy absorbed by the preset positive plate during the impact process, the energy absorbed by the preset negative plate during the impact process, the energy absorbed by the preset separator during the impact process and the energy absorbed by the preset shell during the impact process.

[0073] Exemplarily, during the impact process, when the proportion of the energy absorbed by the preset positive plate in the total energy absorbed by the preset battery is greater than the proportion of the energy absorbed by the preset shell in the total energy absorbed by the preset battery, it indicates that the energy impact obtained by the preset positive plate is greater than that obtained by the preset shell, at this time, the preset battery constructed is prone to positive plate damage during the impact process, so the energy distribution of the preset battery does not meet the design requirement.

[0074] Exemplarily, during the impact process, when the proportion of the energy absorbed by the preset negative plate in the total energy absorbed by the preset battery is greater than the proportion of the energy absorbed by the preset shell in the total energy absorbed by the preset battery, it indicates that the energy impact obtained by the preset negative plate is greater than that obtained by the preset shell, at this time, the preset battery constructed is prone to negative plate damage during the impact process, so the energy distribution of the preset battery does not meet the design requirement.

[0075] That is, when determining whether the energy distribution corresponding to the preset battery meets the design requirement, it is mainly determined whether the energy distribution corresponding to the preset battery meets the design requirement according to the distribution of the energy absorbed by the preset positive plate during the impact process, the energy absorbed by the preset negative plate during the impact process, the energy absorbed by the preset separator during the impact process and the energy absorbed by the preset shell during the impact process.

[0076] In actual application, when the preset battery is designed according to the energy data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell, at least one of the material, thickness, number, size and shape of the preset positive plate, the preset negative plate, the preset separator and the preset shell can be adjusted.

[0077] Exemplarily, in the impact process, when the proportion of the energy absorbed by the preset shell in the total energy absorbed by the preset battery is smaller than the proportion of the energy absorbed by the preset negative plate in the total energy absorbed by the preset battery, the energy absorbed by the preset shell can be increased by adjusting the thickness, material, size or shape of the preset shell, that is, the preset shell bears greater energy impact in the impact process, so as to weaken the energy impact borne by the preset negative plate in the impact process.

[0078] Exemplarily, in the impact process, when the proportion of the energy absorbed by the preset shell in the total energy absorbed by the preset battery is smaller than the proportion of the energy absorbed by the preset negative plate in the total energy absorbed by the preset battery, the energy absorbed by the preset shell can be increased by adjusting the thickness, material, size or shape of the preset shell, that is, the preset shell bears greater energy impact in the impact process, so as to weaken the energy impact borne by the preset negative plate in the impact process.

[0079] In actual application, the simulation test results can be displayed for the convenience of staff to view and analyze.

[0080] The following is described in combination with test content:

[0081] Test object: cylindrical 21700 lithium ion battery.

[0082] Mechanical impact item: heavy object impact (national standard).

[0083] Scheme design: the steel shell in scheme A (multiple lithium ion batteries A) is steel shell A, and the steel shell in scheme B (multiple lithium ion batteries B) is steel shell B.

[0084] Test results: Table 1, mechanical data of cylindrical 21700 lithium ion battery; Table 2, energy absorbed by lithium ion batteries A and B in the heavy object impact process and the corresponding energy proportion; Table 3, test results of lithium ion battery.

[0085] Table 1, mechanical data of cylindrical 21700 lithium ion battery

[0086]

[0087]

[0088] In Table 1, the tensile strength corresponding to steel shell B is the largest among the mechanical data corresponding to the positive active layer, the negative active layer, the positive current collector, the negative current collector, the separator MD, the separator TD, steel shell A and steel shell B, and the tensile strength corresponding to steel shell A is the second. It can be seen that both steel shell A and steel shell B have relatively large tensile strength, while the tensile strength corresponding to the positive active layer, the negative active layer, the positive current collector, the negative current collector, the separator MD and the separator TD is relatively small.

[0089] Table 2. Energy absorbed by lithium-ion batteries A and B during heavy object impact and their corresponding energy percentages.

[0090]

[0091] Table 2 shows a significant difference in the energy absorbed by lithium-ion battery A and lithium-ion battery B. Specifically, in lithium-ion battery A, the positive electrode active layer absorbs the highest amount of energy, accounting for 31.7%, followed by the steel casing and the negative electrode active layer, accounting for 29.1% and 23.4% respectively. In lithium-ion battery B, the steel casing absorbs the highest amount of energy, accounting for 42.7%, followed by the positive electrode active layer and the negative electrode active layer, accounting for 23.5% and 19.6% respectively.

[0092] It is evident that, compared to lithium-ion battery A, lithium-ion battery B increases the energy absorption of the steel casing and reduces the energy absorption of the positive electrode active layer, negative electrode active layer, positive electrode current collector, negative electrode current collector, and separator, especially reducing the energy absorption of the positive and negative electrode active layers. Therefore, during a heavy impact, the electrodes of lithium-ion battery B bear less energy impact and are less prone to damage; in other words, lithium-ion battery B has stronger impact resistance than lithium-ion battery A. Figure 2 , 3 As shown, after the impact test, the bright area on the electrode of lithium-ion battery A's cell is the damaged area of ​​that cell; after the impact test, the bright area on the electrode of another cell of lithium-ion battery A is also the damaged area of ​​that cell; therefore, the cell of lithium-ion battery A failed the impact test, meaning that the cell of lithium-ion battery A is defective. Figure 4 , 5 As shown, after the impact test, the electrodes of lithium-ion battery B were not damaged. This indicates that lithium-ion battery B's cells passed the impact test, meaning they are qualified cells. It also shows that the probability of a short circuit caused by internal damage in lithium-ion battery B is lower than that in lithium-ion battery A. Thus, the probability of thermal runaway in lithium-ion cells can be effectively reduced.

[0093] Table 3. Test Results of Lithium-ion Batteries

[0094]

[0095] In Table 3, the lithium ion battery B in the scheme B has stronger impact resistance than the lithium ion battery A in the scheme A, that is, the lithium ion battery B is easier to pass the impact test than the lithium ion battery A; and the possibility of the cell of the lithium ion battery B to have low voltage is lower than that of the cell of the lithium ion battery A, that is, the lithium ion battery B is less likely to have short circuit (internal diaphragm damage) than the lithium ion battery A. It should be noted that the higher the proportion of the cell to have low voltage, the higher the proportion of the lithium ion cell to have internal short circuit, and the short circuit process is accompanied by heat generation, which is easy to cause the cell to fail.

[0096] In the embodiment, a simulation method of battery mechanical impact test is provided, which comprises: performing tensile test on a sample of a preset positive plate, a sample of a preset negative plate, a sample of a preset diaphragm and a sample of a preset shell respectively to obtain corresponding mechanical data; and / or performing compression test on the sample of the preset positive plate, the sample of the preset negative plate, the sample of the preset diaphragm and the sample of the preset shell respectively to obtain corresponding mechanical data; constructing a battery model corresponding to a preset battery according to material parameters and mechanical data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell; constructing an impact process model according to a preset impact condition, and performing impact simulation test on the battery model corresponding to the preset battery by using the impact process model to obtain a simulation test result, wherein the simulation test result comprises energy data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell. By inputting the material parameters and the mechanical data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell into a preset model software, the battery model corresponding to the preset battery is constructed; and the impact process model is constructed according to the preset impact condition; after the impact simulation test on the battery model by using the impact process model, the energy data corresponding to the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell can be obtained, so that the energy change of the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell in the impact process is quantified, thereby providing a reference for the design of the preset battery.

[0097] The application further provides a simulation device for battery mechanical impact test. Figure 6 As shown in a structural block diagram of a simulation device for battery mechanical impact test. The device comprises an acquisition unit 201, a construction unit 202:

[0098] The acquisition unit 201 is configured to acquire mechanical data of a preset positive plate, a preset negative plate, a preset diaphragm and a preset shell; the mechanical data of the preset positive plate, the preset negative plate, the preset diaphragm and the preset shell is obtained by performing tensile test and / or compression test on a sample of the preset positive plate, a sample of the preset negative plate, a sample of the preset diaphragm and a sample of the preset shell respectively. That is, the above step 101 is used to perform, and the specific process is shown in the above step 101, which will not be repeated here.

[0099] The construction unit 202 is configured to construct a battery model corresponding to the preset battery according to material parameters and mechanical data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell, and to construct an impact process model according to a preset impact condition, and to perform impact simulation testing on the battery model corresponding to the preset battery by using the impact process model, to obtain a simulation testing result, the simulation testing result including energy data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell, wherein the energy data is used to provide a reference for the design of the preset battery. That is, the above steps 102 and 103 are performed, and the specific process is described above in steps 102 and 103, which will not be repeated here.

[0100] The simulation device for battery mechanical impact testing provided in the embodiments of the present application includes an acquisition unit configured to acquire mechanical data of a preset positive plate, a preset negative plate, a preset separator and a preset shell; the mechanical data of the preset positive plate, the preset negative plate, the preset separator and the preset shell is obtained by respectively performing tensile testing and / or compression testing on a sample of the preset positive plate, a sample of the preset negative plate, a sample of the preset separator and a sample of the preset shell; a construction unit is configured to construct a battery model corresponding to the preset battery according to material parameters and mechanical data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell; and to construct an impact process model according to a preset impact condition, and to perform impact simulation testing on the battery model corresponding to the preset battery by using the impact process model, to obtain a simulation testing result, the simulation testing result including energy data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell. By inputting the material parameters and mechanical data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell into a preset model software, a battery model corresponding to the preset battery is constructed; and an impact process model is constructed according to a preset impact condition; after the impact simulation testing on the battery model by using the impact process model, the energy data corresponding to the preset positive plate, the preset negative plate, the preset separator and the preset shell can be obtained, so that the energy change of the preset positive plate, the preset negative plate, the preset separator and the preset shell in the impact process is quantified, to provide a reference for the design of the preset battery.

[0101] Those skilled in the art can understand that all or part of the functions of various methods in the above embodiments can be realized by hardware or by a computer program. When all or part of the functions in the above embodiments are realized by a computer program, the program can be stored in a computer readable storage medium, which can include a read-only memory, a random access memory, a magnetic disk, an optical disk, a hard disk, and the like. The above functions are realized by executing the program by a computer. For example, the program is stored in a memory of a device, and the above functions are realized by executing the program in the memory by a processor. In addition, when all or part of the functions in the above embodiments are realized by a computer program, the program can also be stored in a storage medium such as a server, another computer, a disk, an optical disk, a flash disk, or a mobile hard disk, and is saved in a memory of a local device by downloading or copying, or the system of the local device is updated, and the above functions are realized by executing the program in the memory by a processor.

[0102] The above application of specific examples to the present application is described, which is only used to help understand the present application and does not limit the present application. For those skilled in the art, according to the idea of the present application, a number of simple deductions, deformations or substitutions can be made.

Claims

1. A method of simulating a battery mechanical shock test, characterized by, The preset battery includes a plurality of preset positive electrode sheets, a plurality of preset negative electrode sheets, a plurality of preset separators, and a preset shell, and the method includes: respectively, the sample of the preset positive electrode sheet, the sample of the preset negative electrode sheet, the sample of the preset separator and the sample of the preset shell are subjected to tensile test to obtain corresponding mechanical data; and / or, respectively, the sample of the preset positive electrode sheet, the sample of the preset negative electrode sheet, the sample of the preset separator and the sample of the preset shell are subjected to compression test to obtain corresponding mechanical data; According to the material parameters and mechanical data corresponding to the preset positive electrode sheet, the preset negative electrode sheet, the preset separator and the preset shell, a battery model corresponding to the preset battery is constructed; According to the preset impact condition, an impact process model is constructed, and the impact process model is used for impact simulation test on the battery model corresponding to the preset battery, to obtain a simulation test result, the simulation test result including energy data corresponding to the preset positive electrode sheet, the preset negative electrode sheet, the preset separator and the preset shell; the preset impact condition includes a preset impact speed, a preset impact angle and a preset impact force.

2. The method of claim 1, wherein, According to the material parameters and mechanical data corresponding to the preset positive electrode sheet, the preset negative electrode sheet, the preset separator and the preset shell, a battery model corresponding to the preset battery is constructed, including: The mechanical data corresponding to the preset positive electrode sheet, the preset negative electrode sheet, the preset separator and the preset shell are subjected to homogenization processing to obtain homogenized mechanical data; The material parameters and the homogenized mechanical data corresponding to the preset positive electrode sheet, the preset negative electrode sheet, the preset separator and the preset shell are input into a preset model software to construct a first battery model corresponding to the preset battery; Or, the material parameters and the mechanical data corresponding to the preset positive electrode sheet, the preset negative electrode sheet, the preset separator and the preset shell are input into the preset model software to construct a second battery model corresponding to the preset battery.

3. The method of claim 1, wherein, The method further includes: According to the energy data corresponding to the preset positive electrode sheet, the preset negative electrode sheet, the preset separator and the preset shell, the preset battery is designed to obtain a target battery.

4. The method of claim 3, wherein, According to the energy data corresponding to the preset positive electrode sheet, the preset negative electrode sheet, the preset separator and the preset shell, the preset battery is designed to obtain a target battery, including: Based on the energy data, the energy distribution corresponding to the preset positive electrode sheet, the preset negative electrode sheet, the preset separator and the preset shell is determined; When the energy distribution does not meet the design requirements, the design parameters of at least one of the preset positive electrode sheet, the preset negative electrode sheet, the preset separator and / or the preset shell are adjusted according to the energy distribution to obtain the target battery; wherein the design parameters include at least one of material parameters, structure parameters and a preset number.

5. The method of claim 1, wherein, The method further includes: The simulation test result is displayed.

6. The method of any one of claims 3 to 5, wherein, The mechanical data obtained by the tensile test at least includes one of the following: tensile strength, elongation at break, elastic modulus; The mechanical data obtained by the compression test at least includes one of the following: compression deformation, compression rate.

7. A simulation device for battery mechanical impact testing, characterized in that The device comprises: An acquisition unit is configured to acquire mechanical data of a preset positive electrode sheet, a preset negative electrode sheet, a preset diaphragm and a preset shell, wherein the mechanical data of the preset positive electrode sheet, the preset negative electrode sheet, the preset diaphragm and the preset shell are obtained by performing tensile test and / or compression test on a sample of the preset positive electrode sheet, a sample of the preset negative electrode sheet, a sample of the preset diaphragm and a sample of the preset shell respectively; A construction unit is configured to construct a battery model corresponding to a preset battery according to material parameters and mechanical data corresponding to the preset positive electrode sheet, the preset negative electrode sheet, the preset diaphragm and the preset shell, and to construct an impact process model according to a preset impact condition and perform impact simulation test on the battery model corresponding to the preset battery by using the impact process model to obtain a simulation test result, wherein the simulation test result includes energy data corresponding to the preset positive electrode sheet, the preset negative electrode sheet, the preset diaphragm and the preset shell, and the preset impact condition includes a preset impact speed, a preset impact angle and a preset impact force, and wherein the energy data provides a reference for design of the preset battery.

8. A computer-readable storage medium, characterized in that, A program is included, which can be executed by a processor to implement the method of any one of claims 1-6.

9. A computer program product comprising computer programs and / or instructions, characterized in that, The computer program and / or instructions are executed by the processor to implement the method of any one of claims 1-6.

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