Battery cell detection device

Abstract

The utility model belongs to the technical field of power batteries, and discloses a battery cell detection device, which comprises a mounting rack, a clamp assembly, a displacement sensor and a cooling assembly, the clamp assembly comprises a fixed clamping piece, a movable clamping piece and an elastic piece, the fixed clamping piece is fixedly arranged on the mounting rack, the movable clamping piece and the fixed clamping piece are oppositely arranged, and the elastic piece is arranged on the movable clamping piece. The elastic piece is elastically connected with the fixed clamping piece and the movable clamping piece, and the elastic piece is used for driving the movable clamping piece to approach the fixed clamping piece so as to clamp the battery cell; the displacement sensor is arranged on the fixed clamping piece or the mounting frame, and the displacement sensor is used for detecting the distance between the movable clamping piece and the fixed clamping piece; the cooling assembly is matched with the clamp assembly and used for adjusting the temperature of the fixed clamping piece and the temperature of the movable clamping piece. The battery cell detection device can solve the problems that the detection result is inaccurate and the potential safety hazard of thermal runaway exists when the expansion of the battery cell is detected through a pressure sensor and a visual inspection method in the prior art.

Description

Technical Field

[0001] This utility model relates to the field of power battery technology, and in particular to a cell testing device. Background Technology

[0002] With the rapid development of new energy technologies, lithium-ion batteries, as the power source for new energy vehicles, have advantages such as large capacity, high density, and environmental friendliness, and have thus been widely used.

[0003] During the charging and discharging process of lithium-ion batteries, the active material on the positive electrode releases electrons and embeds them into the negative electrode, causing the positive electrode volume to decrease and the negative electrode volume to increase. Simultaneously, the electrolyte undergoes phase transitions and gas-generating side reactions during charging, also resulting in some volume changes. These factors combined cause the battery cell to experience expansion forces during charging and discharging. With each charge-discharge cycle, these expansion forces gradually accumulate, leading to changes in the cell's dimensions. These dimensional changes not only affect the battery's appearance and lifespan but may also impact its safety. Therefore, real-time monitoring and early warning of cell expansion are crucial.

[0004] Traditional expansion detection methods include pressure sensor methods and visual inspection. Pressure sensor methods suffer from insufficient accuracy and susceptibility to interference. Visual inspection methods are highly sensitive to lighting conditions; insufficient light, strong light, and large changes in light can all affect the monitoring results, and they are unsuitable for environments with low light levels inside energy storage batteries. Furthermore, the temperature rises during cell testing, posing a potential thermal runaway risk and thus increasing the overall testing hazard. Utility Model Content

[0005] The purpose of this invention is to provide a battery cell testing device that can solve the problems of inaccurate test results and potential thermal runaway safety hazards in existing methods of detecting battery cell expansion using pressure sensors and visual inspection.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A battery cell testing device, comprising:

[0008] Mounting rack;

[0009] A clamping assembly includes a fixed clamping member, a movable clamping member, and an elastic member. The fixed clamping member is fixedly disposed on the mounting frame. The movable clamping member is disposed opposite to the fixed clamping member. The elastic member elastically connects the fixed clamping member and the movable clamping member. The elastic member is used to drive the movable clamping member to move closer to the fixed clamping member to clamp the battery cell.

[0010] A displacement sensor is disposed on the fixed clamping member or the mounting bracket, and the displacement sensor is used to detect the distance between the movable clamping member and the fixed clamping member;

[0011] A cooling assembly, which cooperates with the clamping assembly, is used to regulate the temperature of the fixed clamping member and the movable clamping member.

[0012] As an optional solution for the aforementioned cell detection device, the displacement sensor is an eddy current sensor.

[0013] As an optional solution to the aforementioned cell testing device, the cooling assembly includes:

[0014] Cooling channels are provided in both the fixed clamping member and the movable clamping member;

[0015] A drive structure for driving the flow of medium within the cooling channel.

[0016] As an optional embodiment of the aforementioned cell testing device, the cell testing device further includes a temperature sensor, which includes multiple detection ends for contacting the cell to detect the temperature of the cell, and the temperature sensor is communicatively connected to the cooling assembly.

[0017] As an optional embodiment of the aforementioned cell detection device, the cell detection device further includes an alarm component, which is communicatively connected to the displacement sensor.

[0018] As an optional solution to the aforementioned cell detection device, the alarm component includes a warning light and / or a buzzer.

[0019] As an optional solution to the aforementioned cell testing device, the mounting bracket includes:

[0020] The seat body, wherein the elastic element is connected to or abuts against the seat body;

[0021] A support member is disposed on the base body and connected to the fixed clamping member. The movable clamping member is located between the base body and the fixed clamping member.

[0022] As an optional solution for the aforementioned cell testing device, the movable clamping member is slidably connected to the support member;

[0023] And / or, the cell testing device further includes a guide structure, which slidably connects the movable clamp and the base.

[0024] As an optional solution for the above-mentioned cell testing device, the guide structure is nested with the elastic element, or the elastic element is sleeved outside the support element.

[0025] As an optional solution for the above-mentioned cell testing device, the mounting frame includes an upper base plate and a lower base plate connected to each other, and the elastic element is connected to the upper base plate;

[0026] The cell testing device also includes a pressure sensor, which is clamped between the upper base plate and the lower base plate.

[0027] The beneficial effects of this utility model are:

[0028] The battery cell testing device provided by this utility model uses a displacement sensor to detect the expansion displacement of the battery cell, thereby calculating the expansion force, resulting in more accurate results. Furthermore, the displacement sensor does not need to contact the battery cell, thus preventing the battery cell from being punctured during the test and causing danger. By setting up a cooling component to control the temperature of the battery cell, thermal runaway due to overheating is avoided, thereby ensuring the safety of the operator. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the battery cell testing device provided by this utility model.

[0030] In the picture:

[0031] 10. Mounting bracket; 11. Base; 111. Lower base plate; 112. Upper base plate; 12. Support component; 13. Top plate; 14. Nut; 20. Clamp assembly; 21. Fixed clamping component; 22. Movable clamping component; 23. Elastic component; 24. Pipe connector; 25. Connecting pipe; 30. Displacement sensor; 40. Pressure sensor; 50. Guide structure; 51. First guide post; 511. Large diameter section; 512. Small diameter section; 52. Second guide post; 100. Battery cell. Detailed Implementation

[0032] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0033] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" 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. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0034] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0035] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0036] like Figure 1 As shown, this embodiment provides a battery cell testing device, including a mounting frame 10, a clamping assembly 20, and a displacement sensor 30. The clamping assembly 20 includes a fixed clamping member 21, a movable clamping member 22, and an elastic member 23. The fixed clamping member 21 is fixedly disposed on the mounting frame 10, and the movable clamping member 22 is disposed opposite to the fixed clamping member 21. The elastic member 23 elastically connects the fixed clamping member 21 and the movable clamping member 22. The elastic member 23 is used to drive the movable clamping member 22 to approach the fixed clamping member 21 to clamp the battery cell 100. The displacement sensor 30 is disposed on the fixed clamping member 21, and the eddy current sensor is used to detect the expansion displacement of the battery cell 100.

[0037] When testing the battery cell 100, it is placed between the fixed clamping member 21 and the movable clamping member 22. Under the action of the elastic member 23, the movable clamping member 22 and the fixed clamping member 21 cooperate to clamp and fix the battery cell 100. After the battery cell 100 expands, the force exerted by the battery cell 100 on the movable clamping member 22 increases, thereby pushing the movable clamping member 22 away from the fixed clamping member 21, and the elastic member 23 further deforms. By detecting the distance between the movable clamping member 22 and the elastic member 30, the expansion displacement and expansion force of the battery cell 100 can be obtained.

[0038] To prevent thermal runaway of the battery cell 100 during testing, the battery cell testing device also includes a cooling component. The cooling component works in conjunction with the clamping assembly 20 to regulate the temperature of the fixed clamping member 21 and the movable clamping member 22, thereby controlling the temperature of the battery cell 100 and preventing thermal runaway of the battery cell 100 due to overheating, thus ensuring the safety of the operator.

[0039] In some embodiments, the cooling assembly includes cooling channels and a driving structure. Cooling channels are provided within both the fixed clamp 21 and the movable clamp 22. The driving structure drives the flow of the medium within the cooling channels. When the cooling assembly is activated, the heat generated by the battery cell 100 is transferred to the medium through the fixed clamp 21 and the movable clamp 22 via the flowing medium, and is carried away with the outflowing medium. This achieves the effect of controlling the temperature of the battery cell 100, preventing thermal runaway due to excessive temperature, and ensuring testing safety.

[0040] In some embodiments, the cooling channels in the fixed clamp 21 and the movable clamp 22 are connected by a connecting pipe 25. The cooling channel in one of the fixed clamp 21 and the movable clamp 22 serves as the medium inlet channel, and the cooling channel in the other serves as the medium outlet channel. The medium is driven by a driving structure to enter through the medium inlet channel and exit through the medium outlet channel after passing through the connecting pipe 25, so as to ensure the cooling effect.

[0041] In some embodiments, both the fixed clamp 21 and the movable clamp 22 are provided with pipe joints 24, which are connected to the cooling channel to facilitate connection to external pipes or drive structures.

[0042] In some embodiments, the drive structure is a water pump.

[0043] In some embodiments, the displacement sensor 30 is an eddy current sensor. An eddy current sensor is a sensor that measures the displacement of an object using the principle of electromagnetic induction; it operates based on the eddy current effect. When a metal conductor approaches the sensor probe, eddy currents are generated in the conductor. The change in these eddy currents is related to the distance between the conductor and the probe. The sensor detects this change in eddy currents, converts it into a voltage signal, and thus calculates the change in displacement or distance. When detecting the displacement of several planes parallel to the metal conductor, the eddy current sensor can perform non-contact measurement on each plane separately. Due to its high resolution, high sensitivity, and wide measurement range, the eddy current sensor can accurately capture minute distance changes between the metal conductor and the sensor probe and convert these changes into readable electrical signals for output. Detecting expansion displacement using an eddy current sensor allows for non-contact measurement, eliminating the need for contact with the battery cell 100 and preventing the risk of puncturing the battery cell 100 during testing.

[0044] In addition, eddy current sensors have the characteristics of high reliability in long-term operation, high sensitivity, strong anti-interference ability, non-contact measurement, and fast response speed, which are beneficial to improving the reliability and accuracy of battery cell testing devices.

[0045] In some embodiments, the eddy current sensor is disposed on the side of the fixed clamp 21 opposite to the movable clamp 22 to avoid the eddy current sensor interfering with the movement of the elastic member 23 and the movable clamp 22.

[0046] Since eddy current sensors need to be used in conjunction with metal conductors for detection, in some embodiments, the structure of the mounting bracket 10, except for the movable clamp 22, can be made of non-metallic materials to avoid interfering with the detection accuracy of the eddy current sensor.

[0047] In some embodiments, the cell detection device further includes a control component, which is electrically connected to the displacement sensor 30 and the cooling component, respectively. The control component can receive the electrical signal from the displacement sensor 30, analyze and process it, and calculate the expansion displacement and expansion force of the cell 100 in combination with the parameters of the elastic element 23 to understand the working state of the cell 100. The control component can also control the start and stop of the cooling component to better control the temperature of the cell 100.

[0048] In some embodiments, the mounting bracket 10 includes a base 11 and a support member 12. An elastic member 23 elastically connects the base 11 and the movable clamping member 22. One end of the support member 12 is connected to the base 11, and the other end of the support member 12 is connected to the fixed clamping member 21. By providing the support member 12, the fixed clamping member 21 and the base 11 are spaced apart, so as to facilitate the placement of the elastic member 23 and the movable clamping member 22 between the fixed clamping member 21 and the base 11.

[0049] In some embodiments, the elastic member 23 is compressive elastic, and the elastic force applied by the elastic member 23 to the movable clamping member 22 is directed toward the fixed clamping member 21 to drive the movable clamping member 22 closer to the fixed clamping member 21, thereby cooperating to clamp the battery cell 100.

[0050] Optionally, the support member 12 can be a support column, which passes through the fixed clamping member 21 and is fixedly connected to the fixed clamping member 21.

[0051] For example, the fixed clamp 21 and the support column can be fixed by a threaded connection. By fixing the fixed clamp 21 and the support column by the threaded connection, the position of the fixed clamp 21 along the length of the support column can be adjusted, thereby adjusting the distance between the fixed clamp 21 and the base 11; the distance between the fixed clamp 21 and the base 11 will affect the initial deformation of the elastic member 23, thereby adjusting the clamping force of the movable clamp 22 and the fixed clamp 21 on the battery cell 100.

[0052] In some embodiments, multiple support members 12 are provided, and the multiple support members 12 are arranged along the circumference of the fixed clamping member 21 to improve the support effect on the fixed clamping member 21.

[0053] In some embodiments, the mounting bracket 10 further includes a top plate 13, which is located on the side of the fixing clamp 21 opposite to the mounting bracket 10, and the top plate 13 is fixedly connected to the support member 12. Optionally, a nut 14 is threaded onto the support member 12, and the support member 12 is threadedly engaged with the top plate 13. The nut 14 is located on the side of the top plate 13 opposite to the fixing clamp 21, and the nut 14 is threadedly connected to the support member 12.

[0054] To improve the stability of the movement of the movable clamping member 22, the movable clamping member 22 is slidably connected to the support member 12, thereby constraining the sliding direction of the movable clamping member 22 through the sliding engagement with the support member 12 and improving the stability of the movable clamping member 22.

[0055] In some embodiments, the movable clamping member 22 is slidably sleeved on the support member 12. When the cell 100 between the movable clamping member 22 and the fixed clamping member 21 expands, the movable clamping member 22 is forced to move away from the fixed clamping member 21, and the movable clamping member 22 slides in engagement with the support member 12.

[0056] In some other embodiments, the movable clamping member 22 is provided with a slider, and the support member 12 is provided with a slide groove or slide rail that slides with the slider. The movable clamping member 22 and the support member 12 are slidably connected through the cooperation of the slider and the slide rail.

[0057] In some embodiments, the cell testing device further includes a guide structure 50, which is slidably connected to the movable clamp 22 and the base 11 to guide the movement of the movable clamp 22 and improve the stability of the movable clamp 22.

[0058] In some embodiments, the guide structure 50 includes a first guide post 51 and a second guide post 52. The first guide post 51 is connected to the movable clamping member 22, and the second guide post 52 is connected to the base 11. The first guide post 51 and the second guide post 52 are nested together. When the battery cell 100 is placed between the fixed clamping member 21 and the movable clamping member 22, and when the battery cell 100 expands, the nesting depth of the first guide post 51 and the second guide post 52 increases; after the battery cell 100 is removed, the nesting depth of the first guide post 51 and the second guide post 52 decreases.

[0059] Optionally, the second guide post 52 is a hollow post, and the first guide post 51 is slidably inserted inside the second guide post 52.

[0060] In some embodiments, the base 11 is provided with a guide hole, the interior of the second guide post 52 is connected to the guide hole, and the first guide post 51 can slide through the guide hole. By providing a guide hole, sufficient movement space can be provided for the first guide post 51, avoiding interference between the first guide post 51 and the base 11, which would affect the expansion of the cell 100.

[0061] To limit the movement distance of the movable clamping member 22, the first guide post 51 includes a large-diameter section 511 and a small-diameter section 512. The outer diameter of the large-diameter section 511 is larger than the outer diameter of the small-diameter end. The small-diameter end of the large-diameter section 511, which is connected to the movable clamping member 22, passes through the second guide post 52. The outer diameter of the large-diameter section 511 is larger than the inner diameter of the second guide post 52, so that the large-diameter section 511 can abut against the end face of the second guide post 52, thereby limiting the maximum distance between the movable clamping member 22 and the fixed clamping member 21.

[0062] In some embodiments, the elastic element 23 is nested with the guide structure 50 to constrain the elastic element 23 through the guide structure 50, ensuring that the direction of the elastic force remains fixed. Specifically, the first guide post 51 is a hollow post, and the elastic element 23 is disposed inside the first guide post 51.

[0063] In some other embodiments, the elastic element 23 may be sleeved outside the second guide post 52, or the elastic element 23 may be sleeved outside the support post, so as to ensure that the direction of the elastic force of the elastic element 23 will not be deviated when it deforms.

[0064] To prevent excessive expansion of the battery cell 100 from affecting operator safety, in some embodiments, the battery cell detection device further includes an alarm component, which is communicatively connected to the displacement sensor 30. Specifically, the alarm component is electrically connected to the displacement sensor 30 via a control component. After receiving the electrical signal detected by the displacement sensor 30, the control component calculates and analyzes the expansion displacement and expansion force of the battery cell 100. When the expansion force exceeds a preset force or the expansion displacement exceeds a preset displacement, the control component activates the alarm component to alert the operator to the status of the battery cell 100.

[0065] In some embodiments, the alarm component includes at least one of a warning light and a buzzer to alert the operator to the status of the battery cell 100 through light information and a buzzer.

[0066] To prevent thermal runaway of the battery cell 100 during testing and ensure operator safety, in some embodiments, the battery cell testing device further includes a temperature sensor. The temperature sensor includes a temperature detection end that contacts the outer surface of the battery cell 100 to detect its temperature. By detecting the temperature of the battery cell 100, its operating temperature can be monitored to reflect its internal state.

[0067] Optionally, the temperature sensor is communicatively connected to the control component so as to control the alarm component to sound an alarm when the temperature of the battery cell 100 exceeds a preset temperature, so as to remind the operator to pay attention to the status of the battery cell 100.

[0068] In existing technologies, temperature monitoring of the battery cell 100 typically involves placing a temperature sensor on its surface. However, this sensor only has one detection point, meaning it can only capture the temperature at the location in direct contact with the sensor. Since a battery cell 100 failure could occur at any point within the cell, further temperature increases could lead to the entire cell 100 becoming uncontrollable. Using only a single detection point can result in missed detections and fails to comprehensively reflect the battery's condition.

[0069] To address the aforementioned issues, in some embodiments, the temperature sensor includes multiple detection terminals for connection to the outer wall of the battery cell 100 to detect the temperature at multiple locations on the battery cell 100, thereby avoiding missed detections.

[0070] Optionally, the temperature sensor is a thin-film multi-point thermocouple sensor. Thin-film multi-point thermocouple sensors have high detection accuracy and multiple temperature measurement points, and can be designed according to the size of the battery cell 100 to ensure that there are enough temperature measurement points on the surface of the battery cell 100 for temperature monitoring.

[0071] For example, the temperature sensor can have 16 or more temperature measurement points.

[0072] In some embodiments, the control component can control the cooling component to start and stop based on the detection results of the temperature sensor. For example, when the temperature sensor detects that the temperature of the battery cell 100 is higher than a first preset temperature, the control component controls the cooling component to start; when the temperature sensor detects that the temperature of the battery cell 100 has dropped to a second preset temperature, the control component controls the cooling component to stop, wherein the second preset temperature is less than or equal to the first preset temperature. Through the cooperation of the temperature sensor, the control component, and the cooling component, the temperature of the battery cell 100 can be accurately controlled, which can both prevent thermal runaway of the battery cell 100 and avoid energy waste.

[0073] In some embodiments, the mounting frame 10 includes an upper base plate 112 and a lower base plate 111 connected together, and the elastic element 23 is connected to the upper base plate 112. The cell detection device also includes a pressure sensor 40, which is clamped between the upper base plate 112 and the lower base plate 111, wherein the pressure sensor 40 is electrically connected to the control component. This configuration enables the pressure sensor 40 to detect the magnitude of the force applied by the elastic element 23 to the upper base plate 112, and to obtain the force exerted by the elastic element 23 on the mounting frame 10 when the cell 100 is clamped in the movable clamping member 22 and the fixed clamping member 21 before detection. In other words, the pressure sensor 40 can detect the initial force applied by the clamping assembly 20 to the cell 100, facilitating the control component's analysis and calculation of the cell 100's expansion displacement and expansion force, thereby improving the accuracy of the expansion displacement and expansion force results.

[0074] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A battery cell testing device, characterized in that, include: Mounting bracket (10); The clamp assembly (20) includes a fixed clamping member (21), a movable clamping member (22), and an elastic member (23). The fixed clamping member (21) is fixedly disposed on the mounting frame (10). The movable clamping member (22) is disposed opposite to the fixed clamping member (21). The elastic member (23) elastically connects the fixed clamping member (21) and the movable clamping member (22). The elastic member (23) is used to drive the movable clamping member (22) to approach the fixed clamping member (21) to clamp the battery cell (100). A displacement sensor (30) is disposed on the fixed clamp (21) or the mounting bracket (10). The displacement sensor (30) is used to detect the distance between the movable clamp (22) and the fixed clamp (21). The displacement sensor (30) is an eddy current sensor. The displacement sensor (30) is located on the side of the fixed clamp (21) away from the movable clamp (22). A cooling assembly, which cooperates with the clamp assembly (20), is used to regulate the temperature of the fixed clamp (21) and the movable clamp (22); A temperature sensor, comprising a plurality of detection terminals for contact with the battery cell (100) to detect the temperature of the battery cell (100), the temperature sensor being communicatively connected to the cooling assembly.

2. The cell testing device according to claim 1, characterized in that, The cooling assembly includes: Cooling channels are provided in both the fixed clamp (21) and the movable clamp (22); A drive structure for driving the flow of medium within the cooling channel.

3. The cell testing device according to claim 1 or 2, characterized in that, The cell detection device also includes an alarm component, which is communicatively connected to the displacement sensor (30).

4. The cell testing device according to claim 3, characterized in that, The alarm components include warning lights and / or buzzers.

5. The cell testing device according to claim 1 or 2, characterized in that, The mounting bracket (10) includes: The seat (11) is connected to or abuts against the elastic element (23); A support member (12) is disposed on the base (11), the support member (12) is connected to the fixed clamping member (21), and the movable clamping member (22) is located between the base (11) and the fixed clamping member (21).

6. The cell testing device according to claim 5, characterized in that, The movable clamp (22) is slidably connected to the support (12); And / or, the cell testing device further includes a guide structure (50) that slidably connects the movable clamp (22) and the base (11).

7. The cell testing device according to claim 6, characterized in that, The guide structure (50) is nested with the elastic element (23), or the elastic element (23) is sleeved outside the support element (12).

8. The cell testing device according to claim 1 or 2, characterized in that, The mounting bracket (10) includes an upper base plate (112) and a lower base plate (111) connected to each other, and the elastic element (23) is connected to the upper base plate (112); The cell testing device also includes a pressure sensor (40), which is clamped between the upper base plate (112) and the lower base plate (111).

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