Battery cell charging and discharging expansion stress measuring device

Abstract

The invention provides a cell charging and discharging expansion stress measuring device, which comprises a box body, the first surface of the box body is provided with an accommodating groove, and the box body comprises a first end plate and a second end plate which are oppositely arranged; the supporting plate is arranged in the containing groove, is parallel to the first end plate and can move along the inner wall of the box body in the direction perpendicular to the first end plate; the first end of the moving assembly penetrates through the second end plate and is connected with the supporting plate, the second end of the moving assembly is exposed out of the second end plate, and the moving assembly can move in the direction perpendicular to the first end plate; the pressure sensor is detachably connected with the inner wall of the box body and abuts against the surface of the side, facing the second end plate, of the supporting plate. The device can be suitable for square battery cells with different sizes; whether the battery cell is excessively expanded in the charging and discharging process or not and whether destructive influence is generated on the battery module or the battery pack or not can be judged, so that safe use of the battery cell is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of battery cell testing, and in particular to a device for measuring battery cell charging and discharging expansion stress. Background Art

[0002] During the charging and discharging process, the volume of the battery cell will change due to the combined effect of various factors. For example, since the expansion coefficient of the electrolyte inside the battery cell is large, the volume of the electrolyte will increase when the temperature rises; although the expansion coefficient of the positive and negative electrode materials of the battery cell is smaller than that of the electrolyte, they will also expand to a certain extent as the temperature rises; the positive and negative electrode materials of the battery cell will undergo different degrees of phase change during the charging and discharging process, that is, the change of lattice structure, which will also cause the volume of the positive and negative electrode materials to change. The combination of the above phenomena is the thermal expansion of the battery cell.

[0003] The thermal expansion of the battery cell has a certain impact on the battery performance and safety. It will cause the pressure inside the battery casing to increase, thereby affecting the strength and sealing of the battery casing, causing the gap between the positive and negative electrodes to become smaller, increasing the risk of internal short circuits, and changing the contact area between the positive and negative electrodes and the diaphragm, thereby affecting the internal resistance and capacity of the battery.

[0004] By measuring the expansion stress generated during the charging and discharging process of the battery cell, it can be inferred whether the expansion stress within this range will cause excessive thermal expansion of the battery cell and further produce destructive effects, and whether the normal operation of the battery cell can be guaranteed. Therefore, it is very important to measure the expansion stress during the charging and discharging process of battery cells of different specifications. Summary of the invention

[0005] In view of this, the present invention provides a device for measuring the expansion stress of battery cells during charge and discharge, so as to measure the expansion stress of battery cells of different specifications.

[0006] The battery cell charge and discharge expansion stress measuring device provided by the present invention comprises:

[0007] A box body, wherein a first surface of the box body is provided with a receiving groove, and the box body comprises a first end plate and a second end plate which are arranged opposite to each other;

[0008] A support plate, the support plate is disposed in the accommodating groove, is parallel to the first end plate, and can move along the inner wall of the box body in a direction perpendicular to the first end plate;

[0009] A moving component, wherein a first end of the moving component passes through the second end plate and is connected to the support plate, a second end of the moving component is exposed from the second end plate, and the moving component can move in a direction perpendicular to the first end plate;

[0010] A pressure sensor is detachably connected to the inner wall of the box body and abuts against a side surface of the support plate facing the second end plate.

[0011] Optionally, the moving component includes:

[0012] A positioning tube, wherein a first end of the positioning tube passes through the second end plate and is rotatably connected to the support plate, a second end of the positioning tube is exposed from the second end plate, and an outer wall of the positioning tube is at least partially provided with an external thread;

[0013] A nut is fixed to a side surface of the second end plate facing away from the accommodating groove, and the positioning tube is threadedly connected to the nut.

[0014] Optionally, the battery cell charge and discharge expansion stress measurement device also includes: a guide plate, which is arranged between the support plate and the second end plate and fixedly connected to the inner wall of the box body, and the positioning tube passes through the guide plate and is movably connected to the guide plate.

[0015] Optionally, a positioning hole is formed through the side wall of the box body, and a positioning pin passes through the positioning hole and abuts against the guide plate.

[0016] Optionally, the battery cell charge and discharge expansion stress measurement device further includes: a support tube, wherein the support tube is mounted in the accommodating groove between the first end plate and the support plate.

[0017] Optionally, the battery cell charge and discharge expansion stress measurement device further includes: a bracket, which is arranged between the support plate and the second end plate and is detachably connected to the inner wall of the box body, and the pressure sensor is fixedly connected to the bracket.

[0018] Optionally, a blind hole is formed on a surface of one side of the support plate facing the second end plate, and the pressure sensor is inserted into the blind hole.

[0019] Optionally, the battery cell charge and discharge expansion stress measurement device further includes: a reinforcing plate, the reinforcing plate is fixedly connected to a side surface of the second end plate facing the accommodating groove, and the moving component passes through the reinforcing plate.

[0020] Optionally, a avoidance hole is opened on the second end plate, and the connecting line of the pressure sensor passes through the avoidance hole.

[0021] Optionally, a plurality of the movable components are provided, and the plurality of the movable components are arranged at intervals, and the first end of each of the movable components passes through the second end plate and is connected to the support plate.

[0022] Compared with the prior art, the above technical solution provided by the present invention has at least the following beneficial effects:

[0023] By adopting the battery cell charge and discharge expansion stress measuring device of the present invention, the support plate is driven to move relative to the first end plate by means of a moving component, and the space range between the first end plate and the support plate is adjusted, so that it can be suitable for square battery cells of different sizes; by means of the first end plate and the support plate tightly clamping the square battery cell, a pressure sensor is used to monitor the expansion stress applied to the support plate by the square battery cell at different stages of the charge and discharge process, so that the degree of expansion deformation of the square battery cell during the charge and discharge process can be inferred, and then it can be judged whether the battery cell of the manufacturing specification will produce excessive expansion during the charge and discharge process, and whether it will have a destructive effect on the battery module or battery pack, thereby ensuring the safe use of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A three-dimensional diagram of a device for measuring expansion stress of a battery cell during charging and discharging according to an embodiment of the present invention;

[0025] Figure 2 for Figure 1 Another angle schematic diagram of the battery cell charging and discharging expansion stress measurement device.

[0026] Reference numerals:

[0027] 1: box body; 101: receiving groove; 102: first end plate; 103: second end plate; 2: support plate; 3: moving component; 301: positioning tube; 302: nut; 4: pressure sensor; 5: guide plate; 6: positioning pin; 7: support tube; 8: bracket; 9: reinforcement plate; 10: avoidance hole. DETAILED DESCRIPTION

[0028] The embodiments of the present invention will be further described below in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only simplified descriptions for the convenience of describing the present invention, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0029] Figure 1 A three-dimensional diagram of a device for measuring expansion stress of a battery cell during charging and discharging according to an embodiment of the present invention; Figure 2 for Figure 1Another angle diagram of the battery cell charge and discharge expansion stress measurement device is shown. Figure 1 and Figure 2 As shown, the battery cell charge and discharge expansion stress measuring device includes a box body 1, a support plate 2, a moving component 3 and a pressure sensor 4. A receiving groove 101 is provided on the first surface of the box body 1, and the box body 1 includes a first end plate 102 and a second end plate 103 arranged opposite to each other; the support plate 2 is arranged in the receiving groove 101, parallel to the first end plate 102, and can move along the inner wall of the box body 1 in a direction perpendicular to the first end plate 102; the first end of the moving component 3 penetrates the second end plate 103 and is connected to the support plate 2, and the second end of the moving component 3 is exposed from the second end plate 103, and the moving component 3 can move in a direction perpendicular to the first end plate 102; the pressure sensor 4 is detachably connected to the inner wall of the box body 1, and abuts against a side surface of the support plate 2 facing the second end plate 103.

[0030] When in use, the moving assembly 3 is adjusted to move the moving assembly 3 away from the first end plate 102, thereby driving the support plate 2 connected thereto to move in the same direction, thereby expanding the range between the first end plate 102 and the support plate 2, and leaving a sufficiently large space between the first end plate 102 and the support plate 2. The square battery cell is placed in the receiving groove 101 between the first end plate 102 and the support plate 2, so that one side of the square battery cell abuts against the first end plate 102, and the moving assembly 3 is adjusted to move the moving assembly 3 toward the first end plate 102, thereby driving the support plate 2 connected thereto to move in the same direction, until the support plate 2 abuts against the other side of the square battery cell, and the pressure sensor 4 is fixedly connected to the inner wall of the box body 1, and the probe of the pressure sensor 4 abuts against the support plate 2, and the connecting line of the pressure sensor 4 is connected to an external device capable of reading pressure data, at which time, the pressure sensor 4 can detect the reverse force exerted by the square battery cell on the support plate 2. After the pressure sensor 4 is installed, continue to apply external force to the mobile component 3 to increase the reverse force of the support plate 2 on the square battery cell until the pressure data monitored by the pressure sensor 4 reaches the range required for measuring the battery cell expansion stress. At this time, the square battery cell is charged and discharged. With the different stages of the charging and discharging process, the square battery cell expands to different degrees, and then generates different degrees of expansion stress on the support plate 2. The pressure sensor 4 monitors the expansion stress applied by the square battery cell to the support plate 2 in real time, and transmits the expansion stress data to the external device. According to the change of the expansion stress during the charging and discharging process of the square battery cell, the degree of expansion deformation that may occur in the square battery cell during the charging and discharging process can be analyzed, and then it can be determined whether the square battery cell under test will be over-expanded.

[0031] By using the battery cell charge and discharge expansion stress measuring device of the present invention, the support plate 2 is driven to move relative to the first end plate 102 with the help of the moving component 3, and the space range between the first end plate 102 and the support plate 2 is adjusted, so that it can be suitable for square battery cells of different sizes; by means of the first end plate 102 and the support plate 2 tightly clamping the square battery cell, the pressure sensor 4 is used to monitor the expansion stress applied by the square battery cell to the support plate 2 at different stages of the charge and discharge process, and the degree of expansion deformation of the square battery cell during the charge and discharge process can be inferred, and then it can be judged whether the battery cell of the manufacturing specification will produce excessive expansion during the charge and discharge process, and whether it will have a destructive effect on the battery module or battery pack, thereby ensuring the safe use of the battery cell.

[0032] like Figure 1 and Figure 2 As shown, in this embodiment, the box body 1 is a hollow rectangular parallelepiped. Figure 1 The U-shaped plate in the middle is surrounded by the first end plate 102 on the left and the second end plate 103 on the right, and the middle part encloses a receiving groove 101. The middle plate of the U-shaped plate is a rectangular plate body, and vertical plates are vertically extended upward at the edges of the front and rear sides. The first end plate 102 and the second end plate 103 are respectively fixedly connected to the opposite ends of the two vertical plates, thereby blocking the openings on the left and right sides of the U-shaped plate, and the first end plate 102 and the second end plate 103 are respectively perpendicular to the middle plate of the U-shaped plate, so that the two are parallel to each other and have the same height as the U-shaped plate. The overall length of the box body 1 is 300mm and the height is 115mm. Each plate is made of rigid thin plates. The support plate 2 is a rectangular thin plate that matches the cross-section of the accommodating groove 101. The left end of the movable component 3 passes through the box body 1 and is connected to the right side surface of the support plate 2, and the right end is exposed from the box body 1. The movable component 3 can move back and forth in a direction perpendicular to the first end plate 102, thereby driving the support plate 2 to move back and forth in a direction perpendicular to the first end plate 102, thereby adjusting the size of the space between the first end plate 102 and the support plate 2 to be suitable for battery cells of different sizes or battery cells of different stacking numbers. The movable component 3 can be of any structural form, as long as it can drive the support plate 2 to move back and forth and adjust the size of the space between the support plate 2 and the first end plate 102. The pressure sensor 4 is a mature prior art, and its specific working principle will not be repeated here. The connecting line of the pressure sensor 4 extends to the outside of the box body 1, and can be connected to the controller and the display screen to convert the monitored pressure data and expansion stress data into intuitive digital pressure values ​​for the operator to read and analyze.

[0033] Optionally, the moving assembly 3 includes a positioning tube 301 and a nut 302. The first end of the positioning tube 301 penetrates the second end plate 103 and is rotatably connected to the support plate 2, the second end of the positioning tube 301 is exposed from the second end plate 103, and at least part of the outer wall of the positioning tube 301 is provided with an external thread; the nut 302 is fixed to the side surface of the second end plate 103 facing away from the receiving groove 101, and the positioning tube 301 is threadedly connected to the nut 302. This arrangement simplifies the structural composition of the moving assembly 3 and facilitates assembly and operation.

[0034] like Figure 1 and Figure 2 As shown, in this embodiment, the second end plate 103 is penetrated with a connecting hole, and a nut 302 is fixedly connected to the right side of the second end plate 103, and the nut 302 is coaxially arranged with the connecting hole, and the inner diameter of the connecting hole is slightly larger than the inner diameter of the nut 302. The positioning tube 301 is a cylindrical tube with a total length of 300 mm, and the outer wall of the length range of the left part of the center is a smooth surface, and the outer wall of the length range of 140 mm to the right of the center is provided with an external thread. The left smooth outer wall part of the positioning tube 301 penetrates the nut 302 and the connecting hole to the box body 1, and is rotatably connected with the support plate 2 by means of a bearing. The right external thread part of the positioning tube 301 is threadedly connected with the nut 302. By rotating the positioning tube 301, the screw connection position of the positioning tube 301 and the nut 302 is adjusted, thereby adjusting the length of the positioning tube 301 screwed into the box body 1, that is, adjusting the relative distance between the support plate 2 and the first end plate 102, so that it can be suitable for battery cells of different sizes or different numbers of stacked batteries.

[0035] Optionally, the battery cell charge and discharge expansion stress measuring device further includes a guide plate 5, which is disposed between the support plate 2 and the second end plate 103, and is fixedly connected to the inner wall of the box body 1, and the positioning tube 301 passes through the guide plate 5 and is movably connected to the guide plate 5. The guide plate 5 is provided, and the positioning tube 301 passes through the guide plate 5 and is then connected to the support plate 2, so that when the positioning tube 301 is long, the guide plate 5 supports and guides the positioning tube 301, so that after the positioning tube 301 passes through the second end plate 103 and the guide plate 5, under the common load of the two, it stably extends into the box body 1 in a direction perpendicular to the first end plate 102, and is connected to the support plate 2 in the box body 1, so as to prevent the positioning tube 301 from being deviated in direction during the process of extending into the box body 1.

[0036] like Figure 1As shown, in this embodiment, the guide plate 5 is configured as a rectangular plate body, fixedly connected to the circumferential inner wall of the receiving groove 101, and its shape matches the cross section of the receiving groove 101. A connecting hole is also provided on the guide plate 5 at the position corresponding to the position where the positioning tube 301 passes through the second end plate 103, so that the positioning tube 301 can pass through, and the inner diameter of the connecting hole is slightly larger than the outer diameter of the positioning tube 301, so that the positioning tube 301 can smoothly reciprocate relative to the guide plate 5, so as to drive the support plate 2 to reciprocate relative to the first end plate 102. According to the actual application, the specific shape and size of the guide plate 5 can be adjusted, and the specific fixed position in the receiving groove 101 can also be adjusted.

[0037] Optionally, a positioning hole is formed through the side wall of the box body 1, and the positioning pin 6 passes through the positioning hole and abuts against the guide plate 5. The abutment of the positioning pin 6 against the guide plate 5 further fixes the guide plate 5 to prevent the guide plate 5 from moving when the positioning tube 301 moves back and forth.

[0038] like Figure 1 and Figure 2 As shown, in this embodiment, positioning holes are respectively opened on the side walls of the box body 1 on both sides of the extension direction of the guide plate 5, corresponding to the position of the guide plate 5, and the positioning pins 6 pass through the positioning holes on both sides until they abut against the end faces of the guide plate 5 at both ends, thereby further limiting the guide plate 5.

[0039] Optionally, the battery cell charge and discharge expansion stress measurement device further includes a support tube 7, and the support tube 7 is arranged in the receiving groove 101 between the first end plate 102 and the support plate 2. When the support tube 7 is arranged between the first end plate 102 and the support plate 2, when the battery cell is placed in the receiving groove 101 between the two, the battery cell no longer contacts the bottom of the receiving groove 101, but contacts the support tube 7. The support tube 7 supports the battery cell, so that the surface contact between the battery cell and the bottom of the receiving groove 101 is changed to line contact between the battery cell and the support tube 7, thereby reducing the contact area and further reducing the friction between the battery cell and the support tube 7.

[0040] like Figure 1 and Figure 2As shown, in this embodiment, through holes are respectively provided at corresponding positions on the second end plate 103, the guide plate 5 and the support plate 2, and a nut is coaxially fixed at the position corresponding to the through hole on the right side wall of the second end plate 103. Two support tubes 7 are provided, which penetrate the nut, the second end plate 103, the guide plate 5 and the support plate 2 respectively, and finally are rotatably connected with the first end plate 102 by means of a bearing. The outer wall of the support tube 7 near the second end plate 103 is provided with an external thread, and the support tube 7 is fixedly connected with the second end plate 103 by means of the screw connection between the support tube 7 and the nut, that is, the position of the support tube 7 in the box body 1 is fixed. The two support tubes 7 are arranged in parallel at the same horizontal height to facilitate the joint loading of the battery cell. The support tube 7 can also be arranged parallel to the first end plate 102, or arranged obliquely with the first end plate 102, or can be arranged only in the space between the first end plate 102 and the support plate 2, as long as it can load the battery cell.

[0041] Optionally, the battery cell charge and discharge expansion stress measuring device further includes a bracket 8, which is disposed between the support plate 2 and the second end plate 103, and is detachably connected to the inner wall of the box body 1, and the pressure sensor 4 is fixedly connected to the bracket 8. This arrangement can achieve flexible arrangement of the pressure sensor 4 while achieving connection with the inner wall of the box body 1 by means of different structural forms of the bracket 8.

[0042] The bracket 8 can be detachably connected to the inner wall of the box body 1 in any manner. According to the different structural forms of the pressure sensor 4 and the different angle requirements for the connection with the support plate 2, the bracket 8 can be set to facilitate connection with the box body 1 and to facilitate fixing any structural form of the pressure sensor 4. Figure 1 As shown, in this embodiment, the bracket 8 is arranged perpendicular to the bottom of the accommodating groove 101, the lower end is connected to the bottom of the accommodating groove 101, and the upper end is connected to the pressure sensor 4.

[0043] Optionally, a blind hole is formed on one side of the support plate 2 facing the second end plate 103, and the pressure sensor 4 is inserted into the blind hole. In this arrangement, the pressure sensor 4 is limited by the blind hole to prevent relative displacement between the pressure sensor 4 and the support plate 2, which affects the accuracy of the monitoring data.

[0044] The battery cell is placed in the receiving groove 101 between the first end plate 102 and the support plate 2, and after the moving assembly 3 is adjusted and the support plate 2 is driven to apply a satisfying external force to the battery cell, the probe of the pressure sensor 4 is inserted into the blind hole and the pressure sensor 4 is fixed. When a bracket 8 is provided, after the probe of the pressure sensor 4 is inserted into the blind hole, the bracket 8 is fixed to the inner wall of the box body 1, and the fixed position is suitable for carrying and fixing the pressure sensor 4, and then the pressure sensor 4 is fixedly connected to the bracket 8.

[0045] Optionally, the battery cell charge and discharge expansion stress measuring device further includes a reinforcing plate 9, which is fixedly connected to a surface of the second end plate 103 on one side facing the receiving groove 101, and the moving component 3 passes through the reinforcing plate 9. The reinforcing plate 9 is provided to reinforce the position where the moving component 3 passes through the second end plate 103, thereby improving the stability of the second end plate 103 and further improving the stability of the entire measuring device.

[0046] like Figure 1 and Figure 2 As shown, in this embodiment, corresponding to the position where the movable component 3 passes through the second end plate 103, a rectangular reinforcement plate 9 of a certain thickness is fixed on the inner wall of the second end plate 103. After the movable component 3 passes through the second end plate 103 and the reinforcement plate 9, it extends to the interior of the box body 1.

[0047] Optionally, a relief hole 10 is provided on the second end plate 103, and the connecting wire of the pressure sensor 4 passes through the relief hole 10. The relief hole 10 is provided to facilitate the connecting wire of the pressure sensor 4 to pass through the side of the box body 1.

[0048] like Figure 1 As shown, in this embodiment, an avoidance hole 10 is opened at the center of the second end plate 103 and the center of the guide plate 5. The connecting line of the pressure sensor 4 passes through the box body 1 through the avoidance hole 10 and is connected to an external device to transmit the monitored pressure data and expansion stress data to the external device.

[0049] Optionally, a plurality of moving components 3 are provided, and the plurality of moving components 3 are arranged at intervals, and the first end of each moving component 3 penetrates the second end plate 103 and is connected to the support plate 2. In this arrangement, the plurality of moving components 3 provide stable support to the support plate 2, and a balanced external force is applied at the same time, so that the support plate 2 moves stably in the box body 1, and further a stable and balanced external force is applied to the battery cell.

[0050] like Figure 1 and Figure 2 As shown, in this embodiment, a total of four moving components 3 are provided, each two forming a group, respectively close to the front and rear side walls of the box body 1 in the figure, and the two moving components 3 in each group are arranged at intervals along the support plate 2. According to actual application conditions, the number of moving components 3 and the specific connection position with the support plate 2 can be adjusted.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for measuring expansion stress during charge and discharge of a battery cell, characterized in that: include: A box body, wherein a first surface of the box body is provided with a receiving groove, and the box body comprises a first end plate and a second end plate which are arranged opposite to each other; A support plate, the support plate is disposed in the accommodating groove, is parallel to the first end plate, and can move along the inner wall of the box body in a direction perpendicular to the first end plate; A moving component, wherein a first end of the moving component passes through the second end plate and is connected to the support plate, a second end of the moving component is exposed from the second end plate, and the moving component can move in a direction perpendicular to the first end plate; A pressure sensor is detachably connected to the inner wall of the box body and abuts against a side surface of the support plate facing the second end plate.

2. The battery cell charge and discharge expansion stress measuring device according to claim 1, characterized in that: The mobile assembly comprises: A positioning tube, wherein a first end of the positioning tube passes through the second end plate and is rotatably connected to the support plate, a second end of the positioning tube is exposed from the second end plate, and an outer wall of the positioning tube is at least partially provided with an external thread; A nut is fixed to a side surface of the second end plate facing away from the accommodating groove, and the positioning tube is threadedly connected to the nut.

3. The battery cell charge and discharge expansion stress measuring device according to claim 2, characterized in that: Also includes: The guide plate is arranged between the support plate and the second end plate and is fixedly connected to the inner wall of the box body. The positioning tube passes through the guide plate and is movably connected to the guide plate.

4. The battery cell charge and discharge expansion stress measuring device according to claim 3, characterized in that: A positioning hole is formed through the side wall of the box body, and a positioning pin passes through the positioning hole and abuts against the guide plate.

5. The battery cell charge and discharge expansion stress measuring device according to any one of claims 1 to 4, characterized in that: Also includes: A support tube is mounted in the receiving groove between the first end plate and the support plate.

6. The battery cell charge and discharge expansion stress measuring device according to any one of claims 1 to 4, characterized in that: Also includes: A bracket is arranged between the support plate and the second end plate, and is detachably connected to the inner wall of the box body; and the pressure sensor is fixedly connected to the bracket.

7. The battery cell charge and discharge expansion stress measuring device according to any one of claims 1 to 4, characterized in that: A blind hole is formed on a surface of one side of the support plate facing the second end plate, and the pressure sensor is inserted into the blind hole.

8. The battery cell charge and discharge expansion stress measuring device according to any one of claims 1 to 4, characterized in that: Also includes: A reinforcing plate is fixedly connected to a surface of the second end plate on one side facing the accommodating groove, and the moving component passes through the reinforcing plate.

9. The battery cell charge and discharge expansion stress measuring device according to any one of claims 1 to 4, characterized in that: The second end plate is provided with an avoidance hole, through which the connecting wire of the pressure sensor passes.

10. The battery cell charge and discharge expansion stress measuring device according to any one of claims 1 to 4, characterized in that: There are multiple movable components, which are arranged at intervals. The first end of each movable component passes through the second end plate and is connected to the support plate.

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