Power battery cell detection workbench

Abstract

The invention discloses a power battery cell detection workbench, and relates to the field of new energy automobile battery cell detection, the power battery cell detection workbench comprises a battery cell transfer mechanism, a battery cell detection mechanism and a battery cell conveying mechanism, the battery cell detection mechanism comprises a placing table, a bearing platform, a pressing plate and a detection piece, the bearing platform can move in the vertical direction to be supported at the bottom of the electrode lug on the lowest layer, the detection piece comprises two detection heads, the detection heads can move in the vertical direction to abut against the top of the electrode lug on the uppermost layer, and during detection, the pressing plate firstly moves downwards to extrude the top of the battery cell body; then the two detection heads synchronously move downwards and are in contact conduction with the tabs, and the resistance value of the battery cell body is detected; the battery cell detection mechanism is matched with the battery cell transfer mechanism and the battery cell conveying mechanism, so that automatic battery cell detection is realized, the detection efficiency is improved, a strain gauge is mounted in a detection head (a probe or a test piece), the defects of tab folding or dislocation and the like are detected, and unqualified battery cells are prevented from flowing into a battery assembly link.

Description

Technical Field

[0001] The present invention relates to a new energy vehicle battery cell detection technology, and in particular to a power battery cell detection workbench. Background Art

[0002] In the manufacturing of new energy vehicle power battery cells, the stacking process is one of the core technologies. A multi-pole structure is formed by stacking positive and negative electrodes and diaphragms. The precise stacking of the pole tabs directly affects the conductivity and safety of the battery. The resistance value of the battery cell needs to be tested during the production process, and it needs to be tested through a full inspection. In the existing detection method, it is generally tested one by one manually, and the detection efficiency is low. It is easy to miss inspections due to human factors, causing some products with defects such as folded pole tabs to flow into subsequent processes. If not detected, the folded pole tabs may cause abnormal internal resistance of the battery and increase battery safety risks. Summary of the Invention

[0003] The purpose of the present invention is to provide a power battery cell testing workbench to solve the above-mentioned deficiencies in the prior art.

[0004] In order to achieve the above-mentioned purpose, the present invention provides the following technical solutions: a power battery cell detection workbench, comprising a cell transfer mechanism, a cell detection mechanism and a cell conveying mechanism, the cell detection mechanism comprising a placement table, a supporting platform, a pressure plate and a detection piece, the cell transfer mechanism is used to transfer the cell body to be detected to the top of the placement table, the supporting platform can move in the vertical direction to support the bottom of the lowest layer of pole ears, the detection piece includes two detection heads, the detection heads can move in the vertical direction to abut against the top of the uppermost layer of pole ears, during detection, the pressure plate first moves downward to squeeze on the top of the cell body, and then the two detection heads move downward synchronously and contact and conduct with the pole ears to detect the resistance value of the cell body, and the cell conveying mechanism moves the detected cell body out of the placement table.

[0005] Furthermore, the detection component includes a mounting frame and a protective cover, the detection head is mounted on the mounting frame, and the detection head is located at the bottom of the protective cover and can move relative to the protective cover.

[0006] Furthermore, a strain gauge is installed on the detection head to detect the deformation change of the detection head when the tab is under pressure.

[0007] Furthermore, the detection head is a columnar probe, the axial direction of the columnar probe is arranged in the vertical direction, the upper end of the columnar probe is connected to an elastic support arm, and the strain gauge is pasted on the maximum strain area of ​​the elastic support arm.

[0008] Furthermore, the detection head is a sheet-shaped test piece, which is arranged horizontally. The test piece is installed on a rotating seat, which is fixedly installed at the bottom of the rotating shaft. The surface of the rotating shaft is rotatably connected to the mounting frame and the inner wall of the protective cover. The rotating shaft is connected to a rotating part for driving its rotation, and the strain gauge is pasted on the maximum strain area of ​​the test piece.

[0009] Furthermore, the rotating part includes an L-shaped bracket, one end of the L-shaped bracket is fixedly connected to a sliding sleeve, the sliding sleeve is provided with a sliding pin, a guide groove is provided on the surface of the rotating shaft, and the sliding pin is slidably connected to the guide groove. When the detection head moves downward, the rotating shaft moves downward relative to the sliding sleeve, and is rotated 90° through the cooperation of the guide groove and the sliding pin, so that the end of the test piece moves from the protective cover to above the pole ear.

[0010] Furthermore, at least two test pieces are mounted on the rotating seat, each test piece on the same rotating seat is connected and conductive, and a strain gauge is pasted on the maximum strain area of ​​each test piece.

[0011] Furthermore, the cell transfer mechanism includes a clamping member and a transfer member, the clamping member is used to clamp the upper and lower surfaces of the cell body, and the transfer member is used to transport the cell body to a placement table, and the placement table has a channel for the clamping member to be moved out.

[0012] Furthermore, the battery cell detection mechanism further includes a support frame, the support frame is fixedly mounted with a crossbeam, and the crossbeam is mounted with a first driving member for driving the pressure plate to move in a vertical direction.

[0013] Furthermore, a fixing bracket is fixedly mounted on the top of the pressure plate, and a second driving member for driving the detection head to move in a vertical direction is provided on the fixing bracket, and one end of the L-shaped bracket is fixedly mounted on one side of the fixing bracket.

[0014] Compared with the prior art, the power battery cell testing workbench provided by the present invention has the following features:

[0015] Beneficial effects:

[0016] The power battery cell inspection workbench realizes automated cell inspection and improves inspection efficiency by cooperating with the cell inspection mechanism, the cell transfer mechanism, and the cell conveying mechanism. Strain gauges are installed in the inspection head (probe or test piece) to detect defects such as tab folding or misalignment, thereby preventing unqualified cells from entering the battery assembly process and improving the accuracy and reliability of the inspection results. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments described in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0018] Figure 1 A schematic diagram of the overall structure provided by an embodiment of the present invention;

[0019] Figure 2 A schematic diagram of the structure of a battery cell detection mechanism provided in an embodiment of the present invention;

[0020] Figure 3 A schematic diagram of the partial structure of a battery cell detection mechanism provided in an embodiment of the present invention;

[0021] Figure 4 A schematic diagram of the partial structure of a battery cell detection mechanism using a columnar detection head according to an embodiment of the present invention;

[0022] Figure 5 The embodiment of the present invention provides Figure 4 Enlarged view of point A in the middle;

[0023] Figure 6 A schematic diagram of the partial structure of a cell detection mechanism using a sheet-like detection head according to an embodiment of the present invention;

[0024] Figure 7 The embodiment of the present invention provides Figure 6 Schematic diagram of the local structure;

[0025] Figure 8 The embodiment of the present invention provides Figure 7 Schematic diagram of the rear structure;

[0026] Figure 9 A schematic diagram of a structure of setting multiple test pieces provided in an embodiment of the present invention;

[0027] Figure 10 A schematic structural diagram of a cell transfer mechanism provided in an embodiment of the present invention;

[0028] Figure 11 A schematic structural diagram of a battery cell conveying mechanism provided in an embodiment of the present invention.

[0029] Description of reference numerals:

[0030] 1. Battery cell transfer mechanism; 11. Clamping member; 12. Transfer member; 2. Battery cell detection mechanism; 21. Placement table; 211. Channel; 22. Support platform; 23. Press plate; 24. Detection member; 241. Detection head; 242. Mounting frame; 243. Protective cover; 244. Strain gauge; 245. Elastic support arm; 246. Rotating seat; 247. Rotating shaft; 248. Rotating member; 2481. L-shaped bracket; 2482. Slide sleeve; 2483. Guide groove; 25. Support frame; 26. Crossbeam; 27. First drive member; 28. Fixed frame; 29. ​​Second drive member; 3. Battery cell conveying mechanism; 31. Conveyor belt; 4. Battery cell body; 41. Tab; 5. Workbench. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0032] For examples, see Figures 1-11 , a power battery cell detection workbench, including a cell transfer mechanism 1, a cell detection mechanism 2 and a cell conveying mechanism 3, the cell detection mechanism 2 includes a placement table 21, a supporting platform 22, a pressing plate 23 and a detection member 24, the cell transfer mechanism 1 is used to transfer the cell body 4 to be detected to the top of the placement table 21, the supporting platform 22 can move in the vertical direction to support the bottom of the lowest layer of pole ear 41, the detection member 24 includes two detection heads 241, the detection head 241 can move in the vertical direction to abut against the top of the uppermost layer of pole ear 41, during detection, the pressing plate 23 first moves downward to squeeze on the top of the cell body 4, and then the two detection heads 241 move downward synchronously and contact the pole ear 41 to detect the resistance value of the cell body 4, and the cell conveying mechanism 3 moves the detected cell body 4 out of the placement table 21;

[0033] like Figure 1 and Figure 10 As shown, the battery cell transfer mechanism 1 includes a clamping member 11 and a transfer member 12. The clamping member 11 is used to clamp the upper and lower surfaces of the battery cell body 4, and the transfer member 12 is used to transport the battery cell body 4 to the placement table 21. The battery cell conveying mechanism 3 includes a conveyor belt 31. When in use, the battery cell transfer mechanism 1 clamps the stacked battery cell body 4, and then transfers the battery cell body 4 to the placement table 21 through the transfer member 12. The battery cell body 4 is inspected on the placement table 21. After the inspection is completed, the battery cell conveying mechanism 3 starts the conveyor belt 31 to smoothly move the inspected battery cell body 4 out of the placement table 21. It should be noted that the specific structure of the clamping member 11 and the transfer member 12 is not described in detail here. It can also be a general manipulator. In order to facilitate the accurate and stable placement of the battery cell body 4, a channel 211 for moving the clamping member 11 out is provided on the placement table 21, as shown Figure 3As shown, the clamp of the clamping member 11 is generally a plate-shaped structure. After the battery cell body 4 is placed on the placement table 21 , the clamping member 11 can be moved out of the channel 211 to avoid affecting the position of the battery cell body 4 .

[0034] Specifically, when the battery cell detection mechanism 2 is working, the supporting platform 22 first moves upward to a certain position, at which the top of the supporting platform 22 contacts the bottom of the lowest pole ear 41 in the stacked pole ears 41, to prevent the pole ear 41 from sagging due to gravity during the detection process, or being bent by the detection head 241, and then the pressing plate 23 moves downward to squeeze the top of the battery cell body 4 to prevent the battery cell body 4 from being displaced during the detection process and to ensure close contact between the layers after lamination. Finally, the two detection heads 241 move downward synchronously, so that the detection head 241 is pressed against the top of the uppermost pole ear 41, and the resistance value of the battery cell body 4 is detected to obtain the resistance value detection result, which is compared with the standard value to determine whether the battery cell performance meets the requirements. If the resistance value exceeds the preset range, the system automatically marks the unqualified battery cell and sends it to the processing area through the conveyor belt 31; it should be noted that the standard value can be entered into the battery cell detection mechanism 2 by the sample data of multiple battery cell bodies 4 that have passed the manual inspection as the basis for setting the standard value and the threshold range. When the test result exceeds the preset threshold, it is judged that the tab 41 has poor contact or internal defects, such as folding or breaking of the tab 41 when stacking, as well as the situation of multiple or insufficient stacking of batteries. Compared with the existing detection method, by replacing manual detection, not only the detection efficiency and accuracy are improved, but also the labor cost and operation risk are greatly reduced, so that the quality and consistency of the battery cell products are improved.

[0035] like Figure 2 and Figure 3 As shown, the detection member 24 includes a mounting frame 242 and a protective cover 243, the detection head 241 is mounted on the mounting frame 242, and the detection head 241 is located at the bottom of the protective cover 243 and can move relative to the protective cover 243. As an optional method, the protective cover 243 can be slidably mounted on the bottom of the mounting frame 242, and provides a downward sliding tendency by its own weight. When the second driving member 29 drives the mounting frame 242 to move downward, the mounting frame 242 and the protective cover 243 move synchronously. When the protective cover 243 moves to the top of the pole lug 41, as the second driving member 29 continues to drive, the protective cover 243 is pushed to the top of the pole lug 41, and then stops, the mounting frame 242 continues to move, and the detection head 241 is moved out to detect the pole lug 41;

[0036] When testing the battery cells, although the above method can detect defective products, when the tab 41 is folded, the test result cannot reflect whether the folding phenomenon occurs. When the folded tab 41 is in the middle of the stacked tabs 41, it is difficult to detect even through manual or machine vision inspection. If the folded tab 41 is transported to qualified products, there may be certain hidden dangers in subsequent use. The folded tab 41 will cause the thickness of the stacked tabs 41 to increase. This factor makes it impossible to identify the thickness data when the two probes detect the resistance of the battery cell at the same time, so as to determine whether the folding occurs. The difficulty here is that even if folding occurs, the thickness change it reflects is small, and it is usually impossible to identify it by directly detecting the thickness. It is necessary to set a method to identify this height difference to determine the possible folding situation.

[0037] In one embodiment of the present invention, a method for solving the above-mentioned problem is provided. Specifically, a strain gauge 244 is installed on the detection head 241 to detect the deformation of the detection head 241 or the change in contact force when the tab 41 is compressed. The strain gauge 244 generates an electrical signal by sensing the deformation, thereby identifying small thickness changes at the tab 41.

[0038] In one embodiment of the present invention, a structural design of a detection head 241 is provided. The detection head 241 is a cylindrical probe. The axial direction of the cylindrical probe is arranged in the vertical direction. The upper end of the cylindrical probe is connected to an elastic support arm 245. The strain gauge 244 is pasted on the maximum strain area of ​​the elastic support arm 245. The material of the elastic support arm 245 includes but is not limited to spring steel or titanium alloy to ensure that the tab 41 can be deformed when it is under pressure. The maximum strain area is usually the bending part of the elastic support arm 245. It should be understood that the strain gauge 244 is a sensor that works based on the strain effect principle of metal materials. The principle is that when a metal conductor undergoes mechanical deformation (stretching or compression), its resistance value will change with the deformation amount. By measuring the change in resistance value, the degree of deformation can be calculated. This is a prior art and will not be described in detail here.

[0039] During the test, the columnar detection head 241 (probe) presses the tab 41 downward, and the top of the probe transmits pressure through the elastic support arm 245. The strain gauge 244 senses the deformation and generates an electrical signal, accurately reflecting the slight change in the thickness of the tab 41. When testing the battery body 4 of the same specification, under the setting of the same movement stroke of the detection head 241, if the tab 41 is folded, the electrical signal output by the strain gauge 244 is different from the others, thereby effectively identifying the folding phenomenon and ensuring the accuracy of the test. Specifically, when the tab 41 is folded, the stacked tab 41 is folded. 1 When the thickness increases, the bending degree of the support arm increases, the deformation of the strain gauge 244 increases, the resistance change rate increases accordingly, and the output electrical signal has a difference (such as the deviation from the standard value after conversion into voltage); It should be noted that in order to improve the accuracy of the detection, the tabs 41 can be manually folded in the battery body 4 after stacking, and the electrical signal characteristics output by the strain gauge 244 are recorded according to the number and position of the folding, and a database is established for comparison during subsequent automatic detection; when there are too many or too few stacked chips, it can be identified through the data information of the probe.

[0040] In one embodiment of the present invention, another structural design of the detection head 241 is provided. The detection head 241 is a sheet-like test piece. The test piece is arranged horizontally. The test piece is mounted on a rotating seat 246. The rotating seat 246 is fixedly mounted on the bottom of the rotating shaft 247. The surface of the rotating shaft 247 is rotatably connected to the mounting frame 242 and the inner wall of the protective cover 243. The rotating shaft 247 is connected to a rotating member 248 for driving its rotation. Similarly, the strain gauge 244 is pasted on the maximum strain area of ​​the test piece. The working mode of the strain gauge 244 is the same as described above and will not be repeated here. The sheet-like detection head 241 (test piece) is on the rotating member 24 8, it can be moved into the protective cover 243 and above the pole ear 41. The protective cover 243 is to protect the detection head 241 and avoid interference from external factors, so that it is only moved to the top of the pole ear 41 for detection when in use. During detection, the test piece moves downward and adheres to the surface of the pole ear 41, and then the corresponding detection is performed. Compared with the aforementioned method, the strain gauge 244 is directly attached to the test piece for detection, which simplifies the structure, and the force change of the test piece is directly transmitted to the strain gauge 244. Compared with the indirect setting method of the elastic support arm 245, the strain gauge 244 has higher detection sensitivity and faster response speed.

[0041] By integrating the strain gauge 244 sensor, the change in the tab stack thickness is converted into a resistance / voltage signal, breaking through the limitations of traditional resistance detection and accurately identifying hidden defects such as tab folding and interlayer misalignment. Combined with the design of elastic support arms or sheet test pieces, the signal sensitivity is improved, thereby enhancing the accuracy and reliability of detection.

[0042] In one embodiment of the present invention, the rotating member 248 may be a servo motor, an output end of which is connected to the rotating shaft 247 , and the rotating shaft 247 is driven to rotate by the servo motor.

[0043] In one embodiment of the present invention, another structural design of a rotating member 248 is provided to solve the problem of lack of space for motor installation. Specifically, the rotating member 248 includes an L-shaped bracket 2481, one end of the L-shaped bracket 2481 is fixedly connected to a sliding sleeve 2482, the sliding sleeve 2482 is provided with a sliding nail, a guide groove 2483 is opened on the surface of the rotating shaft 247, the sliding nail is slidably connected to the guide groove 2483, when the detection head 241 moves downward, the rotating shaft 247 moves downward relative to the sliding sleeve 2482, and rotates 90 degrees through the cooperation of the guide groove 2483 and the sliding nail to enable the end of the test piece to move from the protective cover 243 to above the pole ear 41, the top of the pressure plate 23 is fixedly installed with a fixing frame 28, and the fixing frame 28 is provided with a second driving member 29 for driving the detection head 241 to move in the vertical direction, and one end of the L-shaped bracket 2481 is fixedly installed on one side of the fixing frame 28, as shown in FIG. Figure 7 As shown, the guide groove 2483 consists of two straight grooves and one oblique groove, and the arc of the projection of the oblique groove on the radial plane of the rotating shaft 247 is 90 degrees. The sliding pin (not shown in the figure) is located in the sliding sleeve 2482. When the mounting frame 242 moves downward, it drives the rotating shaft 247 to move downward. At this time, the rotating shaft 247 and the sliding sleeve 2482 move relative to each other, and the sliding pin slides along the oblique groove, driving the rotating shaft 247 to rotate 90°. The test piece is precisely aligned with the top of the pole ear 41. As the mounting frame 242 continues to move downward, the test piece will be pressed on the surface of the pole ear 41 for detection. Similarly, when problems such as the pole ear 41 folding occur, the detection head 241 can respond quickly, accurately measure the deformation data through the strain gauge 244, and promptly feedback abnormal conditions to ensure the accuracy and efficiency of the detection process.

[0044] In one embodiment of the present invention, at least two test pieces are mounted on the rotating base 246. Each test piece on the same rotating base 246 is connected and conductive, and a strain gauge 244 is attached to the maximum strain area of ​​each test piece. Figure 9 As shown, the test pieces work together to synchronously collect multi-point data, improve the overall detection coverage and accuracy, and improve the reliability of the detection results. It is worth mentioning that this method requires the position of the battery body on the placement table 21 to remain consistent each time, thereby ensuring that the position of the tab 41 is relatively fixed, avoiding the test piece from being unable to accurately align with the position of the tab 41 required for detection.

[0045] The battery cell detection mechanism 2 further includes a support frame 25 , on which a crossbeam 26 is fixedly mounted. A first driving member 27 for driving the pressing plate 23 to move in a vertical direction is mounted on the crossbeam 26 .

[0046] In one embodiment of the present invention, the first driving member 27 and the second driving member 29 are general linear motion mechanisms.

[0047] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the present invention.

Claims

1. A power battery cell testing workbench, characterized in that: The invention comprises a cell transfer mechanism (1), a cell detection mechanism (2) and a cell conveying mechanism (3), wherein the cell detection mechanism (2) comprises a placement platform (21), a supporting platform (22), a pressing plate (23) and a detection member (24), wherein the cell transfer mechanism (1) is used to transfer a cell body (4) to be detected to the top of the placement platform (21), wherein the supporting platform (22) can be moved in a vertical direction to be supported on the bottom of the lowest layer of the pole lug (41), and the detection member (24) comprises two detection heads (241), wherein the detection heads (241) can be moved in a vertical direction to abut against the top of the highest layer of the pole lug (41); During testing, the pressing plate (23) first moves downward to press on the top of the battery cell body (4), and then the two testing heads (241) move downward synchronously and contact and conduct with the tabs (41) to detect the resistance value of the battery cell body (4). The battery cell conveying mechanism (3) moves the tested battery cell body (4) out of the placement table (21).

2. A power battery cell testing workbench according to claim 1, characterized in that: The detection member (24) comprises a mounting frame (242) and a protective cover (243); the detection head (241) is mounted on the mounting frame (242); and the detection head (241) is located at the bottom of the protective cover (243) and is movable relative to the protective cover (243).

3. A power battery cell testing workbench according to claim 2, characterized in that: A strain gauge (244) is installed on the detection head (241) for detecting deformation changes of the detection head (241) when the tab (41) is under pressure.

4. A power battery cell testing workbench according to claim 3, characterized in that: The detection head (241) is a columnar probe, the axial direction of the columnar probe is arranged in the vertical direction, the upper end of the columnar probe is connected to an elastic support arm (245), and the strain gauge (244) is attached to the maximum strain area of ​​the elastic support arm (245).

5. A power battery cell testing workbench according to claim 3, characterized in that: The detection head (241) is a sheet-shaped test piece, which is arranged horizontally. The test piece is mounted on a rotating seat (246), and the rotating seat (246) is fixedly mounted on the bottom of a rotating shaft (247). The surface of the rotating shaft (247) is rotatably connected to the mounting frame (242) and the inner wall of the protective cover (243). The rotating shaft (247) is connected to a rotating member (248) for driving the rotating shaft (247). The strain gauge (244) is attached to the maximum strain area of ​​the test piece.

6. A power battery cell testing workbench according to claim 5, characterized in that: The rotating member (248) includes an L-shaped bracket (2481), one end of the L-shaped bracket (2481) is fixedly connected to a sliding sleeve (2482), the sliding sleeve (2482) is provided with a sliding pin, a guide groove (2483) is provided on the surface of the rotating shaft (247), and the sliding pin is slidably connected to the guide groove (2483). When the detection head (241) moves downward, the rotating shaft (247) moves downward relative to the sliding sleeve (2482), and rotates 90 degrees through the cooperation of the guide groove (2483) and the sliding pin, so that the end of the test piece moves from the protective cover (243) to the top of the pole ear (41).

7. A power battery cell testing workbench according to claim 5, characterized in that: At least two test pieces are mounted on the rotating seat (246), each test piece on the same rotating seat (246) is connected and conductive, and a strain gauge (244) is attached to the maximum strain area of ​​each test piece.

8. The power battery cell testing workbench according to claim 1, characterized in that: The battery cell transfer mechanism (1) comprises a clamping member (11) and a transfer member (12), wherein the clamping member (11) is used to clamp the upper and lower surfaces of the battery cell body (4), and the transfer member (12) is used to transport the battery cell body (4) to a placement platform (21), wherein the placement platform (21) has a channel (211) for the clamping member (11) to be moved out.

9. The power battery cell testing workbench according to claim 1, characterized in that: The battery cell detection mechanism (2) further comprises a support frame (25), a crossbeam (26) being fixedly mounted on the support frame (25), and a first driving member (27) for driving the pressing plate (23) to move in a vertical direction being mounted on the crossbeam (26).

10. A power battery cell testing workbench according to claim 6, characterized in that: A fixing frame (28) is fixedly mounted on the top of the pressure plate (23), and a second driving member (29) is provided on the fixing frame (28) for driving the detection head (241) to move in a vertical direction. One end of the L-shaped bracket (2481) is fixedly mounted on one side of the fixing frame (28).

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