Test fixture for battery cell thermal runaway experiments

Abstract

This application relates to a test fixture for a battery cell thermal runaway experiment, comprising a first clamping plate and a second clamping plate arranged opposite to each other along the length direction and spaced apart, wherein a first movable end of the first clamping plate is rotatably connected to a second movable end of the second clamping plate via a first hinge; a third clamping plate and a fourth clamping plate arranged opposite to each other along the length direction and spaced apart, wherein the third clamping plate and the first clamping plate are arranged opposite to each other along the thickness direction, and the fourth clamping plate and the second clamping plate are arranged opposite to each other along the thickness direction, wherein a third movable end of the third clamping plate is rotatably connected to a fourth movable end of the fourth clamping plate via a second hinge; a first fixed end of the first clamping plate is connected to a third fixed end of the third clamping plate via a first fixing member; a second fixed end of the second clamping plate is connected to a fourth fixed end of the fourth clamping plate via a second fixing member; and a first movable end is connected to a third movable end via a first elastic telescopic member, and a second movable end is connected to a fourth movable end via a second elastic telescopic member.

Description

Technical Field

[0001] This application relates to the technical field of battery safety testing, and in particular to a test fixture for cell thermal runaway experiments. Background Technology

[0002] The safety and reliability of battery cells under extreme operating conditions are important indicators for evaluating battery performance. Therefore, thermal runaway performance testing of battery cells before they are put into formal use is an essential task. During thermal runaway testing, the battery cell under test must be clamped in a test fixture to ensure the safety of the testing operation.

[0003] Existing test fixtures mainly consist of a base plate, clamping plates, and bolts. The battery cell to be tested is inserted into the test cavity formed by the base plate and clamping plates. Then, puncture or heating methods are applied to the battery cell to induce thermal runaway, thus aiding in the study of the thermal runaway mechanism. However, the expansion of different parts of the battery cell during thermal runaway generally varies, while the traditional test fixture applies a basically uniform restraint force to all parts of the battery cell. This makes it impossible to study the influence of different locations of the battery cell under different restraint forces and confinement expansion states on the thermal runaway process and results. Summary of the Invention

[0004] Therefore, it is necessary to provide a test fixture for thermal runaway experiments of battery cells to address the problem that existing technologies cannot conduct thermal runaway studies on different locations of the battery cell under different binding forces and restraint expansion states.

[0005] This application proposes a test fixture for battery cell thermal runaway experiments, comprising:

[0006] A first clamping plate and a second clamping plate are arranged opposite each other and spaced apart along the length direction. The first movable end of the first clamping plate is rotatably connected to the second movable end of the second clamping plate through a first hinge.

[0007] A third clamping plate and a fourth clamping plate are arranged opposite each other and spaced apart along their length. The third clamping plate and the first clamping plate are arranged opposite each other and spaced apart along their thickness. The fourth clamping plate and the second clamping plate are arranged opposite each other and spaced apart along their thickness. The third movable end of the third clamping plate is rotatably connected to the fourth movable end of the fourth clamping plate via a second hinge. The first fixed end of the first clamping plate is connected to the third fixed end of the third clamping plate via a first fixing member. The second fixed end of the second clamping plate is connected to the fourth fixed end of the fourth clamping plate via a second fixing member.

[0008] A first elastic telescopic member and a second elastic telescopic member, wherein the first movable end is connected to the third movable end through the first elastic telescopic member, and the second movable end is connected to the fourth movable end through the second elastic telescopic member.

[0009] When conducting cell thermal runaway experiments using the test fixture of this scheme, the cell to be tested is clamped and fixed within the cavity formed by the first, second, third, and fourth clamping plates. At this point, the central region of the cell is precisely located between the first and third movable ends, and between the second and fourth movable ends. Furthermore, the positions where the first and third movable ends contact the central region of the cell differ from those of the second and fourth movable ends. This is because the first movable end is rotatably connected to the second movable end via a first hinge, and the third movable end is rotatably connected to the fourth movable end via a second hinge. Additionally, the first fixed end of the first clamping plate is also connected and fixed to the third fixed end of the third clamping plate via a first fixing member, and the second fixed end of the second clamping plate is also connected and fixed to the fourth fixed end via a second fixing member. The fourth fixed end of the four-clamp plate is connected and fixed to ensure the connection strength of each component and the structural stability of the test fixture. Therefore, when the first elastic telescopic component and the second elastic telescopic component are adjusted separately or simultaneously, the first movable end and the third movable end can be controlled to rotate towards or away from each other according to the test requirements, and / or the second movable end and the fourth movable end can be controlled to rotate towards or away from each other. When the first movable end and the third movable end, as well as the second movable end and the fourth movable end, are close to each other, the binding force applied to different positions in the middle region of the battery cell can be increased. Conversely, the binding force applied to different positions in the middle region of the battery cell can be reduced. In this way, the binding force at different positions in the middle region of the battery cell can be flexibly adjusted, which facilitates the study of the influence of constraint expansion at different positions under different binding force states on the thermal runaway process and results.

[0010] The technical solution of this application will be further described below:

[0011] In one embodiment, the first hinge member includes a first rotating member and a second rotating member. The first rotating member is fixed to the first movable end and has a first connecting portion. The second rotating member is fixed to the second movable end and has a second connecting portion. The first connecting portion and the second connecting portion are rotatably connected.

[0012] Alternatively, the first hinge member includes a first rotating member, a first rotating shaft, and a second rotating member. The first rotating member is fixed to the first movable end and has a first connecting portion, while the second rotating member is fixed to the second movable end and has a second connecting portion. The first connecting portion is rotatably connected to the second connecting portion via the first rotating shaft, thereby achieving a rotatable connection between the first and second movable ends.

[0013] In one embodiment, the second hinge member includes a third rotating member and a fourth rotating member. The third rotating member is fixed to the third movable end and has a third connecting portion. The fourth rotating member is fixed to the fourth movable end and has a fourth connecting portion. The third connecting portion and the fourth connecting portion are rotatably connected.

[0014] Alternatively, the second hinge member includes a third rotating member, a second rotating shaft, and a fourth rotating member. The third rotating member is fixed to the third movable end and has a third connecting portion. The fourth rotating member is fixed to the fourth movable end and has a fourth connecting portion. The third connecting portion is rotatably connected to the fourth connecting portion via the second rotating shaft. This achieves a rotatable connection between the third and fourth movable ends.

[0015] In one embodiment, a first gap is formed between the first movable end and the second movable end; a second gap is formed between the third movable end and the fourth movable end. This prevents collision interference between the first movable end and the second movable end, and between the third movable end and the fourth movable end, during relative rotation.

[0016] In one embodiment, the first elastic telescopic member includes a first telescopic rod and a first elastic element. One end of the first telescopic rod is fixed to the first movable end, and the other end of the first telescopic rod is fixed to the third movable end. The first elastic element is sleeved on the outside of the first telescopic rod, with one end of the first elastic element abutting against the first movable end and the other end of the first elastic element abutting against the third movable end. This allows the first movable end and the third movable end to rotate relative to each other, moving closer or further apart.

[0017] In one embodiment, at least two of the first elastic telescopic members are arranged at intervals along the length direction of the first movable end and the third movable end. This allows for adjustment of the clamping force at different positions in the central region of the battery cell.

[0018] In one embodiment, the second elastic telescopic member includes a second telescopic rod and a second elastic member. One end of the second telescopic rod is fixed to the second movable end, and the other end of the second telescopic rod is fixed to the fourth movable end. The second elastic member is sleeved on the outside of the second telescopic rod, with one end of the second elastic member abutting against the second movable end and the other end of the second elastic member abutting against the fourth movable end. This allows the second movable end and the fourth movable end to rotate relative to each other, moving closer or further apart.

[0019] In one embodiment, at least two second elastic telescopic members are provided, and these at least two second elastic telescopic members are arranged at intervals along the length direction of the second movable end and the fourth movable end. This allows for adjustment of the clamping force at different positions in the central region of the battery cell.

[0020] In one embodiment, at least two first fasteners are provided, spaced apart along the length of the first fixing end and the third fixing end; at least two second fasteners are provided, spaced apart along the length of the second fixing end and the fourth fixing end. This improves the connection strength between the first and third clamping plates and between the second and fourth clamping plates.

[0021] In one embodiment, the test fixture for the cell thermal runaway experiment further includes a heating element. The first clamping plate, the second clamping plate, the third clamping plate, and the fourth clamping plate cooperate to form a clamping cavity, and the heating element is mounted on the side wall of the clamping cavity. This simulates the thermal runaway experiment of the cell under unconstrained conditions. Attached Figure Description

[0022] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application.

[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is an assembly structure diagram of a test fixture for battery cell thermal runaway experiments according to an embodiment of this application.

[0025] Figure 2 for Figure 1 Side view structural diagram.

[0026] Figure 3 for Figure 2 Top view of the structure.

[0027] Figure 4 for Figure 1 A schematic diagram of the explosion structure.

[0028] Explanation of reference numerals in the attached figures:

[0029] 100. Test fixture for thermal runaway experiments of battery cells; 10. First clamping assembly; 11. First clamping plate; 111. First movable end; 112. First fixed end; 12. First hinge; 13. Second clamping plate; 131. Second movable end; 132. Second fixed end; 20. Second clamping assembly; 21. Third clamping plate; 211. Third movable end; 212. Third fixed end; 22. Second hinge; 23. Fourth clamping plate; 231. Fourth movable end; 232. Fourth fixed end; 30. Clamping cavity; 40. First elastic telescopic member; 41. First telescopic rod; 42. First elastic member; 50. Second elastic telescopic member; 51. Second telescopic rod; 52. Second elastic member; 60. First gap; 70. Second gap; 80. First fixing member; 90. Second fixing member. Detailed Implementation

[0030] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0031] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0032] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0033] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0034] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0035] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0036] See Figures 1 to 4 This application illustrates a test fixture 100 for conducting thermal runaway experiments on battery cells, comprising a first clamping assembly 10, a second clamping assembly 20, a first elastic telescopic member 40, and a second elastic telescopic member 50. For example, both the first clamping assembly 10 and the second clamping assembly 20 are designed as flat plates. One of the largest side surfaces of the first clamping assembly 10 and the second clamping assembly 20 are positioned opposite each other at a distance. It is understood that the two largest side surfaces facing each other form a clamping cavity 30, and when the battery cell to be tested is inserted into the clamping cavity 30, the two largest side surfaces press against the opposite two side surfaces of the battery cell to be tested.

[0037] The first clamping assembly 10 includes a first clamping plate 11, a first hinge 12, and a second clamping plate 13, while the second clamping assembly 20 includes a third clamping plate 21, a second hinge 22, and a fourth clamping plate 23.

[0038] The first clamping assembly 10 and the second clamping assembly 20 are stacked and spaced apart to form a clamping cavity 30. That is, the first clamping plate 11 and the second clamping plate 13 are arranged opposite to each other and spaced apart along the length direction, the third clamping plate 21 and the fourth clamping plate 23 are arranged opposite to each other and spaced apart along the length direction, the third clamping plate 21 and the first clamping plate 11 are arranged opposite to each other and spaced apart along the thickness direction, and the fourth clamping plate 23 and the second clamping plate 13 are arranged opposite to each other and spaced apart along the thickness direction. The first clamping plate 11, the second clamping plate 13, the third clamping plate 21 and the fourth clamping plate 23 cooperate to form a clamping cavity 30, which is used to install and clamp the battery cell to be tested.

[0039] In this application, the first movable end 111 of the first clamping plate 11 is rotatably connected to the second movable end 131 of the second clamping plate 13 via the first hinge 12, and the third movable end 211 of the third clamping plate 21 is rotatably connected to the fourth movable end 231 of the fourth clamping plate 23 via the second hinge 22; the first fixed end 112 of the first clamping plate 11 is connected to the third fixed end 212 of the third clamping plate 21 via the first fixing member 80, and the second fixed end 132 of the second clamping plate 13 is connected to the fourth fixed end 232 of the fourth clamping plate 23 via the second fixing member 90.

[0040] The first elastic telescopic member 40 connects the first movable end 111 and the third movable end 211, and can drive the first movable end 111 and the third movable end 211 to rotate relative to each other and move closer or further apart. The second elastic telescopic member 50 connects the second movable end 131 and the fourth movable end 231, and can drive the second movable end 131 and the fourth movable end 231 to rotate relative to each other and move closer or further apart.

[0041] Please continue reading. Figure 1 and Figure 4 The first fixing member 80 connects and fixes the first fixing end 112 of the first clamping plate 11 and the third fixing end 212 of the third clamping plate 21. The second fixing member 90 connects and fixes the second fixing end 132 of the second clamping plate 13 and the fourth fixing end 232 of the fourth clamping plate 23. By using the first fixing member 80 to connect the first fixing end 112 and the third fixing end 212, and by using the second fixing member 90 to connect the second fixing end 132 and the fourth fixing end 232, the connection strength between the first clamping assembly 10 and the second clamping assembly 20 can be further improved. When the battery cell undergoes thermal runaway expansion, the first clamping assembly 10 and the second clamping assembly 20 can reliably restrain the battery cell to prevent dangerous phenomena such as combustion and explosion, thereby improving test safety.

[0042] Preferably, there are at least two first fixing members 80, and the at least two first fixing members 80 are arranged at intervals along the length direction of the first fixing end 112 and the third fixing end 212; there are at least two second fixing members 90, and the at least two second fixing members 90 are arranged at intervals along the length direction of the second fixing end 132 and the fourth fixing end 232.

[0043] The first clamping plate 11, the second clamping plate 13, the third clamping plate 21, and the fourth clamping plate 23 are all rectangular in structure. Threaded holes are provided at the four apex corners of the first fixed end 112, the third fixed end 212, the second fixed end 132, and the fourth fixed end 232. The first fixing member 80 and the second fixing member 90 are both set as connecting screws. A connecting screw is installed in each set of two axially opposite threaded holes, thereby forming the first clamping assembly 10 and the second clamping assembly 20 connected and fixed by four connecting screws arranged at intervals in the circumferential direction. The connection method and structure are simple, the connection reliability is high, and the assembly and disassembly are convenient.

[0044] Furthermore, by turning the connecting screw, the distance between the first fixed end 112 and the third fixed end 212, as well as between the second fixed end 132 and the fourth fixed end 232, can be flexibly adjusted, thereby adjusting the clamping force on the top and bottom of the battery cell, so as to study the influence of the constraint expansion of the top and bottom of the battery cell under different binding force states on the thermal runaway process and results.

[0045] In summary, implementing the technical solution of this embodiment will have the following beneficial effects: When conducting cell thermal runaway experimental research using the test fixture of this solution, the cell to be tested is installed in the clamping cavity 30 formed by the first clamping component 10 and the second clamping component 20 for clamping and fixing. At this time, the middle region of the cell is exactly located between the first movable end 111 and the third movable end 211, and the second movable end 131 and the fourth movable end 231. Furthermore, the positions where the first movable end 111 and the third movable end 211 contact the middle region of the cell are different from the positions where the second movable end 131 and the fourth movable end 231 contact the middle region of the cell. Since the first movable end 111 is rotatably connected to the second movable end 131 through the first hinge 12, and the third movable end 211 is rotatably connected to the fourth movable end 231 through the second hinge 22, and the first fixed end 112 of the first clamping plate 11 is also connected and fixed to the third fixed end 132 of the third clamping plate 13 through the first fixing component 80, the... The second fixed end 132 of the second clamping plate 13 is also connected and fixed to the fourth fixed end 232 of the fourth clamping plate 223 through the second fixing member 90 to ensure the connection strength of each component and the structural stability of the test fixture. Therefore, when the first elastic telescopic member 40 and the second elastic telescopic member 50 are operated separately or simultaneously, the first movable end 111 and the third movable end 211 can be controlled to rotate towards or away from each other according to the test requirements, and / or the second movable end 131 and the fourth movable end 231 can be controlled to rotate towards or away from each other. When the first movable end 111 and the third movable end 211 and the second movable end 131 and the fourth movable end 231 are close to each other, the binding force applied to different positions in the middle region of the battery cell can be increased. Conversely, the binding force applied to different positions in the middle region of the battery cell can be reduced. In this way, the binding force at different positions in the middle region of the battery cell can be flexibly adjusted, which facilitates the study of the influence of constraint expansion at different positions under different binding force states on the thermal runaway process and results.

[0046] Understandably, when the first movable end 111 and the third movable end 211, as well as the second movable end 131 and the fourth movable end 231 rotate relative to each other, the relative angles between the first clamping plate 11 and the second clamping plate 13, as well as between the third clamping plate 21 and the fourth clamping plate 23, change.

[0047] The first hinge 12 provides rotational freedom between the first movable end 111 and the second movable end 131, and the second hinge 22 provides rotational freedom between the third movable end 211 and the fourth movable end 231, so that the first movable end 111 and the third movable end 211, as well as the second movable end 131 and the fourth movable end 231, can rotate relative to each other and move closer or further apart. Furthermore, by limiting the range of motion of the first hinge 12 and the second hinge 22, the magnitude of the change in the relative angle between the first clamping plate 11 and the second clamping plate 13, as well as between the third clamping plate 21 and the fourth clamping plate 23, can be limited.

[0048] It should be noted that the number of clamping plates in the test fixture 100 used for cell thermal runaway experiments should not be limited to only four. When the length of the cell to be tested is greater than the length of the test fixture 100 used for cell thermal runaway experiments, the number of clamping plates, hinges and elastic telescopic parts can be appropriately increased to meet the needs of effective clamping of the cell to be tested.

[0049] For example, in one embodiment, the first hinge member 12 includes a first rotating member and a second rotating member. The first rotating member is fixed to the first movable end 111 and has a first connecting portion. The second rotating member is fixed to the second movable end 131 and has a second connecting portion. The first connecting portion and the second connecting portion are rotatably connected.

[0050] Alternatively, as an alternative to the above embodiments, the first hinge member 12 includes a first rotating member, a first rotating shaft, and a second rotating member. The first rotating member is fixed to the first movable end 111 and has a first connecting portion. The second rotating member is fixed to the second movable end 131 and has a second connecting portion. The first connecting portion is rotatably connected to the second connecting portion through the first rotating shaft.

[0051] By connecting the first rotating component and the second rotating component, the first clamping plate 11 and the second clamping plate 13 of the split structure can be connected into one unit. Furthermore, the first connecting part and the second connecting part can be directly rotatably connected or indirectly rotatably connected through the first rotating shaft, thereby providing the required rotational freedom for the first clamping plate 11 and the second clamping plate 13. The connection method and structure are simple, and the rotational reliability is high.

[0052] In another embodiment, the second hinge member 22 includes a third rotating member and a fourth rotating member. The third rotating member is fixed to the third movable end 211 and has a third connecting portion. The fourth rotating member is fixed to the fourth movable end 231 and has a fourth connecting portion. The third connecting portion and the fourth connecting portion are rotatably connected.

[0053] Alternatively, as an alternative to the above embodiments, the second hinge member 22 includes a third rotating member, a second rotating shaft, and a fourth rotating member. The third rotating member is fixed to the third movable end 211 and has a third connecting portion. The fourth rotating member is fixed to the fourth movable end 231 and has a fourth connecting portion. The third connecting portion is rotatably connected to the fourth connecting portion through the second rotating shaft.

[0054] Similarly, by connecting the third rotating component and the fourth rotating component, the split structure of the third clamping plate 21 and the fourth clamping plate 23 can be connected into one unit. Furthermore, by directly rotating the third connecting part and the fourth connecting part or indirectly rotating them through the second rotating shaft, the required rotational freedom of the third clamping plate 21 and the fourth clamping plate 23 can be provided. The connection method and structure are simple, and the rotational reliability is high.

[0055] To facilitate understanding of the technical solution, the first hinge 12 and the second hinge 22 can specifically adopt rotating components such as hinges and hinges. Taking a hinge as an example, the two embodiments of the first hinge 12 and the second hinge 22 mentioned above correspond to hinge structures without a pivot and with a pivot, respectively.

[0056] Preferably, in this application, two of the first hinge member 12 and the second hinge member 22 are provided simultaneously, thereby strengthening the connection strength between the first clamping plate 11 and the second clamping plate 13 and between the third clamping plate 21 and the fourth clamping plate 23, and avoiding connection failure when subjected to the compressive force of thermal runaway expansion of the battery cell.

[0057] Please continue reading. Figure 2 and Figure 3 Based on any of the above embodiments, a first gap 60 is formed between the first movable end 111 and the second movable end 131; a second gap 70 is formed between the third movable end 211 and the fourth movable end 231. It is easy to understand that the purpose of setting the first gap 60 and the second gap 70 is to prevent interference caused by mutual contact when the first clamping plate 11 and the second clamping plate 13, and the third clamping plate 21 and the fourth clamping plate 23, rotate relative to each other. At the same time, it allows the first clamping assembly 10 and the second clamping assembly 20 to obtain a certain range of free deformation space, that is, to allow the clamping cavity 30 to have different sizes, thereby adapting to different battery cell clamping and different degrees of expansion when the battery cell experiences thermal runaway.

[0058] In another embodiment, at least two first elastic telescopic members 40 are provided, and the at least two first elastic telescopic members 40 are arranged at intervals along the length direction of the first movable end 111 and the third movable end 211. Further, at least two second elastic telescopic members 50 are provided, and the at least two second elastic telescopic members 50 are arranged at intervals along the length direction of the second movable end 131 and the fourth movable end 231.

[0059] Different first elastic telescopic members 40 are respectively connected to different positions of the first movable end 111 and the third movable end 211. Similarly, different second elastic telescopic members 50 are respectively connected to different positions of the second movable end 131 and the fourth movable end 231. When a single first elastic telescopic member 40 and second elastic telescopic member 50 are adjusted, or multiple first elastic telescopic members 40 and second elastic telescopic members 50 are adjusted simultaneously, the first movable end 111 and the third movable end 211, as well as the second movable end 131 and the fourth movable end 231, can rotate relative to each other and move closer or further apart. This allows for the application of different clamping forces to different positions in the middle region of the battery cell, thus facilitating the study of the influence of constraint expansion under different binding force states at different positions in the middle of the battery cell on the process and outcome of thermal runaway.

[0060] Please continue reading. Figure 1 and Figure 4Specifically, in one embodiment, the first elastic telescopic member 40 includes a first telescopic rod 41 and a first elastic member 42. One end of the first telescopic rod 41 is fixed to a first movable end 111, and the other end of the first telescopic rod 41 is fixed to a third movable end 211. The first elastic member 42 is sleeved on the outside of the first telescopic rod 41, with one end of the first elastic member 42 abutting against the first movable end 111 and the other end of the first elastic member 42 abutting against the third movable end 211. Further, the second elastic telescopic member 50 includes a second telescopic rod 51 and a second elastic member 52. One end of the second telescopic rod 51 is fixed to a second movable end 131, and the other end of the second telescopic rod 51 is fixed to a fourth movable end 231. The second elastic member 52 is sleeved on the outside of the second telescopic rod 51, with one end of the second elastic member 52 abutting against the second movable end 131 and the other end of the second elastic member 52 abutting against the fourth movable end 231.

[0061] Understandably, the first elastic telescopic member 40 and the second elastic telescopic member 50 adopt the same structural design and working principle. The following explanation uses the first elastic telescopic member 40 as an example. The first telescopic rod 41 has the function of extending and retracting. When the first telescopic rod 41 is retracted, it synchronously drives the first movable end 111 and the third movable end 211 to move closer together, thereby increasing the clamping force on the middle region of the battery cell. At this time, the first elastic member 42 undergoes compression deformation or the degree of compression deformation increases. When the first telescopic rod 41 is extended, the first movable end 111 and the third movable end 211 are pushed away from each other by the elastic force released by the first elastic member 42, thereby reducing the clamping force on the middle region of the battery cell. The working principle of the second elastic telescopic member 50 can be understood with reference to the first elastic telescopic member 40 described above, and will not be repeated here.

[0062] Depending on actual needs, the first telescopic rod 41 and the second telescopic rod 51 can adopt an electric telescopic rod structure or a manual telescopic rod structure. When a manual telescopic rod structure is adopted, both include a threaded rod and a threaded sleeve. The threaded rod is screwed into the threaded sleeve. One end of the threaded rod extending out of the threaded sleeve is connected to and fixed to the first clamping plate 11 and the second clamping plate 13. The end of the threaded sleeve away from the threaded rod is connected to and fixed to the third clamping plate 21 and the fourth clamping plate 23. Therefore, by rotating the threaded rod, the threaded rod can move linearly along the axial direction within the threaded sleeve, thereby achieving the purpose of driving the first movable end 111 and the third movable end 211, as well as the second movable end 131 and the fourth movable end 231, to rotate relative to each other and move closer or further away.

[0063] Furthermore, based on any of the above embodiments, the test fixture 100 for the cell thermal runaway experiment also includes a heating element, which is mounted on the side wall of the clamping cavity 30. During the experiment, the heating element is fixed between the first clamping assembly 10 and the support in the middle region of the cell and / or between the second clamping assembly 20 and the middle region of the cell. On the one hand, by energizing the heating element, the heating element can generate high temperature on the cell, thereby inducing thermal runaway of the cell; on the other hand, by adjusting the tension state of the first elastic element 42 and the second elastic element 52, a relatively low binding force in the middle of the cell can be achieved, thereby simulating a state in which the cell is unrestrained, and then conducting the cell thermal runaway experiment in this state.

[0064] The technical features of the above embodiments can be combined in any way. For the sake of brevity, 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.

[0065] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A test fixture for battery cell thermal runaway experiments, characterized in that, include: A first clamping plate and a second clamping plate are arranged opposite each other and spaced apart along the length direction. The first movable end of the first clamping plate is rotatably connected to the second movable end of the second clamping plate through a first hinge. A third clamping plate and a fourth clamping plate, the third clamping plate and the fourth clamping plate being arranged opposite each other and spaced apart along the length direction, the third clamping plate and the first clamping plate being arranged opposite each other and spaced apart along the thickness direction, the fourth clamping plate and the second clamping plate being arranged opposite each other and spaced apart along the thickness direction, the third movable end of the third clamping plate being rotatably connected to the fourth movable end of the fourth clamping plate via a second hinge, the first fixed end of the first clamping plate being fixedly connected to the third fixed end of the third clamping plate via a first fixing member, and the second fixed end of the second clamping plate being fixedly connected to the fourth fixed end of the fourth clamping plate via a second fixing member; and, The first elastic telescopic member and the second elastic telescopic member, the first movable end is connected to the third movable end through the first elastic telescopic member and can move closer or further away from each other, the second movable end is connected to the fourth movable end through the second elastic telescopic member and can move closer or further away from each other; The first clamping plate, the second clamping plate, the third clamping plate, and the fourth clamping plate cooperate to form a clamping cavity; A first gap is formed between the first movable end and the second movable end; a second gap is formed between the third movable end and the fourth movable end; the first movable end, the third movable end, the second movable end, and the fourth movable end are used to contact different positions in the middle region of the battery cell.

2. The test fixture for cell thermal runaway experiments according to claim 1, characterized in that, The first hinge includes a first rotating member and a second rotating member. The first rotating member is fixed to the first movable end and has a first connecting part. The second rotating member is fixed to the second movable end and has a second connecting part. The first connecting part and the second connecting part are rotatably connected. Alternatively, the first hinge member includes a first rotating member, a first rotating shaft, and a second rotating member. The first rotating member is fixed to the first movable end and has a first connecting portion. The second rotating member is fixed to the second movable end and has a second connecting portion. The first connecting portion is rotatably connected to the second connecting portion through the first rotating shaft.

3. The test fixture for cell thermal runaway experiments according to claim 1, characterized in that, The second hinge member includes a third rotating member and a fourth rotating member. The third rotating member is fixed to the third movable end and has a third connecting part. The fourth rotating member is fixed to the fourth movable end and has a fourth connecting part. The third connecting part and the fourth connecting part are rotatably connected.

4. The test fixture for cell thermal runaway experiments according to claim 1, characterized in that, The second hinge member includes a third rotating member, a second rotating shaft, and a fourth rotating member. The third rotating member is fixed to the third movable end and has a third connecting part. The fourth rotating member is fixed to the fourth movable end and has a fourth connecting part. The third connecting part is rotatably connected to the fourth connecting part through the second rotating shaft.

5. The test fixture for cell thermal runaway experiments according to claim 1, characterized in that, The first elastic telescopic member includes a first telescopic rod and a first elastic element. One end of the first telescopic rod is fixed to the first movable end, and the other end of the first telescopic rod is fixed to the third movable end. The first elastic element is sleeved on the outside of the first telescopic rod, and one end of the first elastic element abuts against the first movable end, and the other end of the first elastic element abuts against the third movable end.

6. The test fixture for cell thermal runaway experiments according to claim 1 or 5, characterized in that, The first elastic telescopic member is provided in at least two, and the at least two first elastic telescopic members are arranged at intervals along the length direction of the first movable end and the third movable end.

7. The test fixture for cell thermal runaway experiments according to claim 1, characterized in that, The second elastic telescopic member includes a second telescopic rod and a second elastic member. One end of the second telescopic rod is fixed to the second movable end, and the other end of the second telescopic rod is fixed to the fourth movable end. The second elastic member is sleeved on the outside of the second telescopic rod, and one end of the second elastic member abuts against the second movable end, and the other end of the second elastic member abuts against the fourth movable end.

8. The test fixture for cell thermal runaway experiments according to claim 1 or 7, characterized in that, The second elastic telescopic member is provided as at least two, and the at least two second elastic telescopic members are arranged at intervals along the length direction of the second movable end and the fourth movable end.

9. The test fixture for cell thermal runaway experiments according to claim 1, characterized in that, The first fixing member is provided in at least two, and the at least two first fixing members are arranged at intervals along the length direction of the first fixing end and the third fixing end; the second fixing member is provided in at least two, and the at least two second fixing members are arranged at intervals along the length direction of the second fixing end and the fourth fixing end.

10. The test fixture for cell thermal runaway experiments according to claim 1, characterized in that, The test fixture for the cell thermal runaway experiment also includes a heating element, which is mounted on the side wall of the clamping cavity.

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