Battery damage impact equipment and consistency test method

Abstract

The invention discloses battery damage impact equipment and a consistency test method, and relates to the field of test and measurement. The electromagnetic attraction structure is arranged to control attraction and falling of the impact structure; the object placing table is used for placing a to-be-impacted battery; when the impact structure falls off, the impact depth is obtained after the impact structure acts on the to-be-impacted battery placed on the storage table, and the device structure is simplified. The damaged battery sample is obtained by adopting the battery damage impact equipment provided by the invention, and the actual impact depth of the damaged battery sample and the deformation depth of the damaged battery sample pole piece are obtained, so that depth consistency and deformation consistency can be obtained. The internal resistance change of a damaged battery sample is cyclically tested by adopting a hybrid power pulse characteristic test method, so that the internal resistance consistency can be obtained, and a battery damage consistency test result is further obtained.

Description

Technical Field

[0001] The present application relates to the field of testing and measurement, and in particular to a battery damage impact device and a consistency testing method. Background Art

[0002] With the rapid development of new energy, the demand for batteries in energy storage, automobiles and other fields is becoming increasingly urgent. In order to meet the relevant R&D and testing needs, it is necessary to develop corresponding test systems.

[0003] There are few existing testing schemes for battery damage. It is crucial to determine the cause of battery damage through reasonable testing methods and further measure the relevant performance changes of damaged batteries to understand the safety and reliability of batteries during use. However, battery damage test experiments are accidental. For battery cells used in battery systems in batches, it is impossible to test them one by one, and thus it is impossible to ensure the consistency of damage test results. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, the present application provides a battery damage impact device and a consistency testing method.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] In a first aspect, the present application provides a battery damage impact device, the battery damage impact device comprising: an electromagnetic attraction structure, an impact structure and a storage platform;

[0007] The electromagnetic attraction structure is used to control the adsorption and detachment of the impact structure; the storage table is used to place the battery to be impacted; when the impact structure falls off, it acts on the battery to be impacted to obtain the impact depth.

[0008] Optionally, the electromagnetic attraction structure is an electromagnet.

[0009] Optionally, the impact structure comprises a steel body and an impact head;

[0010] The impact head is arranged on the steel body; when no battery impact is performed, the steel body is adsorbed on the electromagnetic attraction structure.

[0011] Optionally, the impact head is made of steel.

[0012] Optionally, the impact end of the impact head is hemispherical with a set diameter.

[0013] Optionally, the storage table comprises: a storage platform and a control body; the control body is placed on the storage platform; and the battery to be impacted is placed in a space formed by the control body and the storage platform.

[0014] Optionally, the control body is formed by stacking a plurality of steel monomers in layers.

[0015] Optionally, the storage table further includes a support body;

[0016] The supporting body is arranged on the controlling body.

[0017] In a second aspect, the present application provides a battery damage consistency testing method, the method comprising:

[0018] Select the battery risk point as the impact location;

[0019] Using the battery damage impact device provided above to perform an impact test with a set impact depth or a set impact force according to the impact position, to obtain a damaged battery sample;

[0020] After the damaged battery sample is left to stand for a set time at the test environment temperature, the actual impact depth of the damaged battery sample and the deformation depth of the electrode piece of the damaged battery sample are obtained;

[0021] In the environmental chamber, the hybrid power pulse characteristic test method is used to cyclically test the change of internal resistance of damaged battery samples;

[0022] Determining depth consistency based on actual impact depth of the damaged battery sample;

[0023] Determining deformation consistency based on the deformation depth of the damaged battery sample electrode piece;

[0024] Obtaining internal resistance consistency based on the internal resistance change of the damaged battery sample;

[0025] A battery damage consistency test result is obtained based on the depth consistency, the deformation consistency and the internal resistance consistency.

[0026] Optionally, the battery damage consistency test result is expressed as:

[0027] S = min{S1, S2, S3};

[0028] In the formula, S represents the battery damage consistency test result, S1 represents depth consistency, S2 represents deformation consistency, S3 represents internal resistance consistency, and min represents the minimum value.

[0029] According to the specific embodiments provided by the present application, the present application discloses the following technical effects: the present application controls the adsorption and detachment of the impact structure by setting an electromagnetic attraction structure; the storage table is used to place the battery to be impacted; when the impact structure falls off, it acts on the battery to be impacted placed on the storage table to obtain the impact depth, thereby simplifying the device structure. By adopting the above-mentioned battery damage impact device to obtain a damaged battery sample, the three aspects of external characterization such as the depth of mechanical knock, internal characterization such as the damage depth of the pole piece after the knock scanned by the CT device, and performance characterization such as the impact on the change of internal resistance after mechanical damage are comprehensively considered to comprehensively determine the damage consistency of the battery, thereby more reasonably ensuring the damage consistency of the mechanical damage test. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 A schematic diagram of the structure of a battery damage impact device provided in an embodiment of the present application;

[0032] Figure 2 A flowchart for implementing the battery damage consistency test method provided in an embodiment of the present application;

[0033] Figure 3 A schematic diagram of the overall implementation architecture of the battery damage consistency test method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0035] The purpose of this application is to provide a battery damage impact device and consistency testing method, aiming to solve the problem that the prior art cannot ensure the consistency of damage test experimental results.

[0036] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0037] Example 1

[0038] This embodiment provides a battery damage impact device, such as Figure 1 As shown, the device includes: an electromagnetic attraction structure, an impact structure and a storage platform. The electromagnetic attraction structure is used to control the adsorption and shedding of the impact structure. The storage platform is used to place the battery to be impacted. When the impact structure falls off, it acts on the battery to be impacted to obtain the impact depth.

[0039] In another exemplary embodiment of the present application, in order to further simplify the device structure, the electromagnetic attraction structure used may be an electromagnet. When the battery impact test is performed, the power is turned off, the electromagnetic attraction structure loses its magnetic effect, and the impact structure falls off to act on the battery to be impacted.

[0040] In another exemplary embodiment of the present application, in order to increase the impact performance, the impact structure may include a steel body and an impact head. The impact head is arranged on the steel body. When the battery is not impacted, the steel body is adsorbed on the electromagnetic attraction structure. In order to ensure the low cost and impact strength of the equipment, the impact head is made of steel. And the impact end of the impact head is set to a hemispherical shape with a set diameter (for example, 30 mm). Furthermore, in order to be able to achieve impacts at different battery positions, a plurality of slots may be provided on the steel body in the present application. A clip that matches the slot on the steel body is provided at one end of the impact head to be clamped on the steel body. When impact simulation of other positions of the battery is required, it is only necessary to remove the impact head and clamp the impact head in the slot corresponding to the impact position on the steel body.

[0041] In another exemplary embodiment of the present application, in order to achieve the control of a specific impact force, the weight of the impact structure can be obtained when preparing the device. In this way, the magnitude of the impact force can be obtained by further obtaining the impact distance, so as to achieve damage impact simulation under a specific impact force. The impact force is recorded as Q, Q=mgh. m is the weight of the impact structure, g is the gravitational acceleration, and h is the impact distance.

[0042] In another exemplary embodiment of the present application, in order to facilitate the control of the impact depth, the above-used storage platform may include: a storage platform and a control body. The control body is placed on the storage platform. The battery to be impacted is placed in the space formed by the control body and the storage platform. The control body is formed by stacking multiple steel monomers in layers, so that the impact depth can be controlled under a specific impact force, so as to achieve damage impact simulation of a specific impact depth. Figure 1 As shown, the impact distance is recorded as h, h = H4-H3. Among them, H4 is the sum of the falling distance of the impact structure and the height of the steel body, and H3 is the height of the steel body. Further, the number of control bodies is at least 2.

[0043] In another exemplary embodiment of the present application, in order to reduce the impact of the impact error caused by the deformation of the steel body under the impact force, the present application can also set a support body corresponding to the number of control bodies. The support body is set on the control body. The horizontal cross-section of the support body is larger than the horizontal cross-section of the control body. Through this setting, when the impact structure falls off onto the support body, the support body provides a reverse force to the impact structure to avoid deformation of the steel body of the impact structure.

[0044] Based on the above description, the present application can achieve damage impact simulation under specific impact force by setting up an impact structure, obtaining the weight of the impact structure, and further obtaining the fall-off distance of the impact structure. By using multiple steel monomers to form a control body in a hierarchical stacking manner, the impact depth can be controlled under a specific impact force, thereby achieving damage impact simulation under a specific impact depth.

[0045] Example 2

[0046] This embodiment provides a battery damage consistency test method, such as Figure 2 As shown, the method includes:

[0047] Step 100: Select a battery risk point as the impact position. In actual application, the battery risk point can be determined according to actual experimental needs. For example, the middle point of the battery can be used as the battery risk point, but it is not limited thereto.

[0048] Step 101: Use the battery damage impact device provided in the above embodiment 1 to perform an impact test with a set impact depth or a set impact force according to the impact position to obtain a damaged battery sample. In actual application, the battery can be impacted along the +z direction of the experimental environment (i.e., the spatial vertical direction corresponding to the impact position).

[0049] Step 102: After the damaged battery sample is left to stand for a set time at the test environment temperature, the actual impact depth L1 of the damaged battery sample and the deformation depth L2 of the damaged battery sample pole piece are obtained. In actual application, a vernier caliper can be used to measure the actual impact depth L1 of the damaged battery sample. A CT scanning device is used to obtain the deformation depth L2 of the damaged battery sample pole piece.

[0050] Step 103: In the environmental chamber, the internal resistance change of the damaged battery sample is cyclically tested using the Hybrid Pulse Power Characteristic (HPPC) test method. Among them, HPPC is mainly used to reflect a characteristic of the pulse charge and discharge performance of the power battery. It can complete the test of the DC internal resistance of the battery. Its purpose is to determine the 10-second discharge power and 10-second charging power of the battery pack every 10% state of charge (SOC). Based on this, the process of testing the internal resistance change of the damaged battery sample in step 103 can be described as:

[0051] (1) Charge the battery fully as recommended by the manufacturer and leave it for 1 hour.

[0052] (2) Perform a constant current pulse test.

[0053] (3) Discharge 10% and then let stand for 1 hour.

[0054] (4) Repeat steps (2) and (3) until the battery power is consumed by 90% or reaches the maximum discharge range specified by the manufacturer.

[0055] During the test, the voltage during each rest period needs to be recorded to establish the battery's OCV (open circuit voltage) curve. The test pulse current is performed using two peak currents: low current (25% of the maximum allowable 10s pulse discharge current determined by the manufacturer) and high current (75% of the maximum allowable 10s pulse discharge current determined by the manufacturer).

[0056] Step 104: Obtaining depth consistency based on the actual impact depth of the damaged battery sample.

[0057] Step 105: Obtaining deformation consistency based on the deformation depth of the damaged battery sample electrode.

[0058] Step 106: Obtaining internal resistance consistency based on the internal resistance change of the damaged battery sample.

[0059] Step 107: Obtain the battery damage consistency test result based on the depth consistency, deformation consistency and internal resistance consistency. The battery damage consistency test result is expressed as: S = min{S1, S2, S3}. In the formula, S represents the battery damage consistency test result, S1 represents the depth consistency, S2 represents the deformation consistency, S3 represents the internal resistance consistency, and min represents the minimum value.

[0060] Based on the above description, the overall implementation architecture of the battery damage consistency test method provided in this embodiment is as follows: Figure 3 shown.

[0061] The effect of the battery damage consistency testing method provided by the present invention is described below by way of experiments.

[0062] In this experiment, two fresh battery cells were used as comparison samples, and at least 10 battery cells from the same batch as the comparison samples were used as test samples. A consistency test experiment was carried out under an impact force of 50J. The experimental results are shown in Table 1.

[0063] Table 1 Test results

[0064]

[0065] Furthermore, the battery damage consistency test method provided by this application can effectively (consistency greater than 90%) verify the mechanical damage test method. Only by determining the effectiveness of the test method can we ensure that during the battery development process, the battery developed using this test method meets the relevant performance requirements, making the accuracy higher, thereby providing a reference idea for the design and development of safe battery systems and methods.

[0066] In addition to testing the deformation of CT scans and the damage to the pole pieces, the deformation of the structural damage can also be tested. In the case of mechanical damage, the consistency can be judged from different dimensions. The consistency of mechanical damage results in different dimensions can corroborate each other, and the consistency of mechanical damage results for battery cells is guaranteed from theoretical and measured results (not less than 90%), which effectively verifies that the battery damage consistency test method provided by this application has higher reliability in the case of battery mechanical damage test scenarios.

[0067] In summary, the battery damage consistency test method provided in this application can achieve a consistent evaluation of the degree of battery damage results under mechanical action, provides a feasible solution for the dynamic safety evaluation of the bottom of the electric vehicle power battery pack, and plays a positive role in promoting the green and healthy development of new energy.

[0068] Example 3

[0069] A computer device, which may be a database. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. The processor, the memory and the input / output interface are connected via a system bus, and the communication interface is connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store pending transactions. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, the battery damage consistency test method in Example 2 can be implemented.

[0070] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0071] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0072] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. The same and similar parts between the embodiments can be referenced to each other; at the same time, for those of ordinary skill in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A battery damage impact device, characterized in that: The battery damage impact device comprises: an electromagnetic attraction structure, an impact structure and a storage platform; The electromagnetic attraction structure is used to control the adsorption and detachment of the impact structure; the storage table is used to place the battery to be impacted; when the impact structure falls off, it acts on the battery to be impacted to obtain the impact depth.

2. The battery damage impact device according to claim 1, characterized in that: The electromagnetic attraction structure is an electromagnet.

3. The battery damage impact device according to claim 1, characterized in that: The impact structure includes a steel body and an impact head; The impact head is arranged on the steel body; when no battery impact is performed, the steel body is adsorbed on the electromagnetic attraction structure.

4. The battery damage impact device according to claim 3, characterized in that: The impact head is made of steel.

5. The battery damage impact device according to claim 3, characterized in that: The impact end of the impact head is in a hemispherical shape with a set diameter.

6. The battery damage impact device according to claim 1, characterized in that: The storage table comprises: a storage platform and a control body; the control body is placed on the storage platform; the battery to be impacted is placed in a space formed by the control body and the storage platform.

7. The battery damage impact device according to claim 6, characterized in that: The control body is formed by stacking a plurality of steel monomers in layers.

8. The battery damage impact device according to claim 6, characterized in that: The storage platform also includes a support body; The supporting body is arranged on the controlling body.

9. A battery damage consistency test method, characterized in that: The method comprises: Select the battery risk point as the impact location; Using the battery damage impact device as described in any one of claims 1 to 8, an impact test with a set impact depth or a set impact force is performed according to the impact position to obtain a damaged battery sample; After the damaged battery sample is left to stand for a set time at the test environment temperature, the actual impact depth of the damaged battery sample and the deformation depth of the electrode piece of the damaged battery sample are obtained; In the environmental chamber, the hybrid power pulse characteristic test method is used to cyclically test the change of internal resistance of damaged battery samples; Determining depth consistency based on actual impact depth of the damaged battery sample; Determining deformation consistency based on the deformation depth of the damaged battery sample electrode piece; Obtaining internal resistance consistency based on the internal resistance change of the damaged battery sample; A battery damage consistency test result is obtained based on the depth consistency, the deformation consistency and the internal resistance consistency.

10. The battery damage consistency testing method according to claim 9, characterized in that: The battery damage consistency test results are expressed as: S = min{S1, S2, S3}; In the formula, S represents the battery damage consistency test result, S1 represents depth consistency, S2 represents deformation consistency, S3 represents internal resistance consistency, and min represents the minimum value.

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