A battery pole piece bending tool and method

Abstract

This invention discloses a battery electrode bending fixture and method, belonging to the field of bending technology. It includes a base and an mounting platform. The base is fixedly connected to a cylinder and parallel grippers, with the cylinder positioned above the grippers. The mounting platform supports the mounting body and is fixedly connected to the base, located between the cylinder and the grippers. The mounting body has electrode pieces protruding from its bottom on both sides, the protruding portions being extensions. The telescopic end of the cylinder has a pressing block that abuts against the electrode pieces. The parallel grippers have two fingers that move synchronously away from or towards each other. The tops of the fingers have an upwardly inclined guide surface and a horizontal surface, with the guide surface facing outwards. This battery electrode bending fixture and method avoids the upward movement and bending position deviation that occurs with existing bending fixtures during electrode bending.

Description

Technical Field

[0001] This invention relates to the field of bending technology, specifically to a battery electrode bending fixture and method. Background Technology

[0002] As a key component of a battery, the manufacturing quality of battery electrodes directly affects the battery's electrochemical performance and safety. In some battery structural designs, it is necessary to bend the battery electrodes, typically by bending the tabs or edges, to meet the requirements of cell assembly, tab connection, or encapsulation structures.

[0003] Currently, the bending of battery electrodes is usually accomplished using bending fixtures. Existing bending fixtures generally employ an upper and lower die assembly method. The electrode is placed in the bending groove of the lower die, and the upper die applies bending force to the electrode, causing it to undergo plastic deformation along a predetermined bending line, thereby forming the required angle. However, due to the thinness and softness of the battery electrode sheets, the bending force applied by the upper die during the bending process of the existing bending fixture is not entirely along the bending direction. While the electrode sheet is subjected to the bending force, it will also experience a sliding component along the bending groove direction. The existing fixture lacks an effective anti-slippage limiting structure, which causes the electrode sheet to easily slide upward or shift laterally under the bending force. After the electrode sheet slides upward, its bending position shifts, and the bending line deviates from the predetermined position. At the same time, the electrode sheet material will generate significant elastic rebound after unloading, making the actual bending angle greater than the angle set by the die. When it is necessary to bend both sides of the electrode sheet at the same time, the above-mentioned upward sliding and rebound problems are superimposed, resulting in differences in the stress state and displacement of the two sides of the electrode sheet during the bending process. Ultimately, this leads to inconsistent bending angles and bending depths on both sides of the electrode sheet, which seriously affects the forming quality of the electrode sheet bending. This defect of inconsistent bending on both sides can easily lead to quality problems such as electrode alignment deviation, electrode interference, or even short circuits during subsequent cell winding or stacking assembly. This reduces the yield and reliability of the battery, while also increasing the cost of rework and manual correction, thus hindering the improvement of production efficiency.

[0004] Therefore, it is necessary to provide a battery electrode bending fixture and method to solve the above problems. Summary of the Invention

[0005] In view of the above-mentioned problems in the prior art, the purpose of the present invention is to provide a battery electrode bending fixture and method to solve the problems mentioned in the background art.

[0006] The technical solution adopted by the present invention to solve its technical problem is: a battery electrode bending fixture and method, including a base and an installation platform, wherein a cylinder and a parallel gripper are fixedly connected on the base, and the cylinder is located above the parallel gripper; The mounting platform is used to support the mounting body and is fixedly connected to the machine base. The mounting platform is located between the cylinder and the parallel gripper. The mounting body has pole pieces protruding from the bottom of the mounting body on both sides, and the protruding part is an extension; The cylinder's telescopic end has a pressure block that abuts against the electrode plate; The parallel gripper has two fingers that move away from or towards each other simultaneously. The top of each finger has a guide surface that slopes upwards and a horizontal surface, with the guide surface facing outwards. When the electrode is inserted into the mounting slot, the extension is bent once under the support of the guide surface, and when the finger moves outward, the horizontal surface bends the extension a second time.

[0007] Furthermore, the cylinder has an actuating end that slides up and down, the actuating end being fixedly connected to the top of the pressure block, and both sides of the bottom of the pressure block having arc-shaped portions that match the bending of the upper end of the battery electrode.

[0008] Furthermore, the material of the pressing block is stainless steel.

[0009] Furthermore, the mounting body has through battery slots on both sides, the electrode is located inside the battery slot, and the arc-shaped part is located directly above the battery slot.

[0010] Furthermore, one side of the electrode has an upwardly extending abutment portion, the root of which is elastic, and the abutment portion is configured to abut against the wall of the mounting groove when the electrode enters the mounting groove.

[0011] Furthermore, a gap is formed between the bottom of the mounting body and the top of the finger for the extension to pass through, the height of the gap being greater than the thickness of the extension.

[0012] Furthermore, the mounting platform has a hollow section, and the hollow section has limiting blocks around its perimeter. The mounting body is located inside the limiting blocks and is partially supported by the mounting platform between the hollow section and the limiting blocks.

[0013] Furthermore, this includes the following steps: Step 1: Place the device into the installation platform and adjust the finger position; Step 2: Insert the battery electrode and lower the pressure block to bend the extension once; Step 3: Move your fingers outward to bend the extension a second time; Step 4: After bending, reset each component.

[0014] The beneficial effects of the present invention are as follows: The present invention provides a battery electrode bending fixture and method. The bending fixture is equipped with a pressure block and parallel grippers, which allows the pressure block to simultaneously press down on two electrodes to restrict their position and ensure that the distance of the extension from the battery slot is consistent. By setting a guide surface on the fingers, a pre-bending is completed when the electrode is lowered, which improves the efficiency of subsequent secondary bending, reduces the rebound angle of the extension, and avoids the situation where the existing bending fixture moves upward and the bending position is offset during the electrode bending process. By opening an arc-shaped part, the contact area between the pressure block and the electrode sheet is increased, making the pressure block and the upper bending part of the electrode sheet fit more closely, improving the stability of the electrode sheet during bending, and ensuring that the positions of the electrode sheets on both sides are consistent, improving the consistency of the bending angle and bending depth of the two extensions, and having good force symmetry. The double bending process protects the active material coating on the electrode to the greatest extent. Bending makes the deformation process smoother, reduces the strain rate, and makes the stress distribution inside the material more uniform, avoiding local stress concentration. Large deformation at one time can easily lead to coating cracking, peeling or microcracks in the substrate.

[0015] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0016] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is an overall schematic diagram of the present invention; Figure 2 This is a schematic diagram of the installation platform of the present invention; Figure 3 This is a schematic diagram of the parallel gripper of the present invention; Figure 4 This is a schematic front view of the parallel gripper of the present invention; Figure 5 This is a schematic diagram of the pressing block of the present invention; Figure 6 This is a schematic diagram of the mounting body of the present invention; Figure 7 This is a schematic diagram of the bottom of the mounting body of the present invention; Figure 8 This is a schematic cross-sectional view of the present invention; Figure 9 For the present invention Figure 8 Enlarged diagram of area A in the middle; Figure 10 This is a schematic diagram of the position of the parallel gripper in step one of the present invention; Figure 11 This is a schematic diagram of the bending angle of the supporting part in step two of the present invention. Figure 12 This is a schematic diagram of the secondary bending angle of the supporting part in step three of the present invention; The following are the labeling elements in the figure: 1. Base; 2. Mounting platform; 201. Hollow section; 21. Limiting block; 3. Mounting body; 301. Battery slot; 302. Mounting slot; 31. Electrode; 311. Extension; 312. Supporting section; 4. Cylinder; 41. Actuating end; 42. Pressing block; 421. Arc-shaped section; 5. Parallel gripper; 51. Finger; 511. Guide surface; 512. Horizontal surface; 6. Gap. Detailed Implementation

[0017] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0018] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0019] like Figure 1-12 As shown, the present invention provides a technical solution: a battery electrode bending fixture and method, comprising: The base 1 is fixedly connected to a cylinder 4 and a parallel gripper 5, with the cylinder 4 located above the parallel gripper 5; Mounting platform 2 is used to support mounting body 3 and is fixedly connected to base 1. Mounting platform 2 is located between cylinder 4 and parallel gripper 5. The mounting body 3 has pole pieces 31 protruding from the bottom of the mounting body 3 on both sides, and the protruding part is an extension 311; The telescopic end of cylinder 4 has a pressure block 42 that abuts against electrode 31; The parallel gripper 5 has two fingers 51 that move away from or towards each other simultaneously. The top of the fingers 51 has a guide surface 511 that is inclined upward and a horizontal surface 512, with the guide surface 511 facing outward. When the electrode 31 is inserted into the mounting slot 302, the extension 311 is bent once under the support of the guide surface 511. When the finger 51 moves outward, the horizontal surface 512 bends the extension 311 a second time.

[0020] The cylinder 4 has an actuating end 41 that slides up and down. The actuating end 41 is fixedly connected to the top of the pressure block 42. Both sides of the bottom of the pressure block 42 have arc-shaped parts 421 that match the bending of the upper end of the battery electrode 31.

[0021] The material of the pressure block 42 is stainless steel.

[0022] The mounting body 3 has through battery slots 301 on both sides, the electrode 31 is located inside the battery slots 301, and the arc-shaped part 421 is located directly above the battery slots 301.

[0023] One side of the electrode 31 has a support portion 312 extending obliquely upward. The root of the support portion 312 is elastic. The support portion 312 is configured to abut against the wall of the mounting groove 302 when the electrode 31 enters the mounting groove 302.

[0024] A gap 6 is formed between the bottom of the mounting body 3 and the top of the finger 51 for the extension 311 to pass through, and the height of the gap 6 is greater than the thickness of the extension 311.

[0025] The mounting platform 2 has a hollow section 201, and the hollow section 201 has limiting blocks 21 around its perimeter. The mounting body 3 is located inside the limiting blocks 21 and is partially supported by the mounting platform 2 between the hollow section 201 and the limiting blocks 21.

[0026] In one embodiment, the method for bending the battery electrode is as follows: Specifically, it is divided into the following steps: Step 1: Place the installer onto the installation platform and adjust the finger position: The mounting body 3 is placed inside the hollow part 201, so that the opening area of ​​the battery slot 301 where the battery is installed faces upward and toward the pressure block 42. By controlling the parallel gripper 5, the finger 51 is positioned below the battery slot 301, the seam between the extension 311 and the supporting part 312 is located below the battery slot 301, and the highest point of the battery slot 301 and the extension 311 are directly opposite each other.

[0027] Step 2: Insert the battery electrode and lower the pressure block to bend the extension once: Place the electrode 31 into the mounting slot 302, so that both supporting parts 312 face the battery slot 301. Manually press down the battery electrode 31 so that the supporting parts 312 tilt at an angle towards the main body of the electrode 31. The far end of the supporting part 312 abuts against the wall at the bottom of the mounting slot 302. Install the other electrode 31 into the mounting slot 302 on the other side in the same way. The cylinder 4 is activated, causing the actuator 41 to drive the pressure block 42 to descend. The arc-shaped part 421 gradually approaches the upper bend of the electrode 31 until the arc-shaped part 421 covers the upper bend of the electrode 31. The pressure block 42 then moves the electrode 31 downwards. As the electrode 31 descends, the extension 311 gradually protrudes from the bottom of the battery slot 301 and contacts the guide surface 511. The back of the extension 311 continuously contacts the guide surface 511, so that the bending angle of the extension 311 is consistent with the tilt angle of the guide surface 511. When the cylinder 4 reaches its maximum stroke, the pressure block 42 presses the upper bent portion of the electrode 31 onto the housing of the battery slot 301, thus fixing the position of the electrode 31. At this time, the extension portion 311 of the electrode 31 completes one bend.

[0028] Step 3: Move your fingers outward to bend the extension a second time: Once again, control the fingers 51 on the parallel gripper 5 to move away from each other at both ends. At this time, the extension 311 held by the guide surface 511 gradually transitions from the guide surface 511 to the horizontal surface 512 and bends. The extension 311 is restricted in the gap 6 and forms a 90-degree angle with the electrode 31 of the mounting groove 302. After resting for a period of time, bring your fingers 51 close to each other. At this time, your fingers 51 do not resist the extension 311. The extension 311 gradually rebounds in a free state, and the bending angle rebounds from 90 degrees to about 135 degrees. At this time, the second bending is completed. During the two bending processes mentioned above, the electrode 31 is held by the pressure block 42, the holding part 312 abuts against one side of the mounting groove 302, and the back of the electrode 31 abuts against the other side of the mounting groove 302. This ensures that during bending, the vertical position of the electrode 31 is restricted by the pressure block 42, and the horizontal position is restricted by the holding part 312, so that the electrode 31 will not move in other directions during bending.

[0029] After bending is complete, reset all components: After bending is completed, the control cylinder 4 moves upward, so that the pressure block 42 is released from the restriction on the electrode 31. At this time, the electrode 31 is fixed to the mounting body 3 by the bent extension 311 and the holding part 312, and the bending of the battery electrode 31 is completed. Then the mounting body 3 is taken out from the hollow part 201 and enters the next process. Following the steps above, bend the battery electrode 31 inside the next mounting body 3.

[0030] In summary, this bending fixture, by setting up a pressure block 42 and parallel grippers 5, allows the pressure block 42 to simultaneously press down on two electrode sheets 31 to restrict their position, and ensures that the extension portion 311 extends out of the battery slot 301 at a consistent distance. By setting a guide surface 511 on the finger 51, a pre-bending is completed when the electrode sheet 31 descends, which improves the efficiency of subsequent secondary bending, reduces the rebound angle of the extension portion 311, and avoids the situation in existing bending fixtures where the electrode sheet 31 moves upward and the bending position is offset during the bending process. By providing an arc-shaped portion 421, the contact area between the pressure block 42 and the electrode 31 is increased, making the pressure block 42 and the upper bending portion of the electrode 31 fit more closely, improving the stability of the electrode 31 during bending, and ensuring that the positions of the electrode 31 on both sides are consistent, improving the consistency of the bending angle and bending depth of the two extension portions 311, and ensuring good force symmetry. The double bending process maximizes the protection of the active material coating on electrode 31. Bending makes the deformation process smoother, reduces the strain rate, and makes the stress distribution inside the material more uniform, avoiding local stress concentration. Large deformation at one time can easily lead to coating cracking, peeling or microcracks in the substrate.

[0031] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A battery electrode bending fixture, characterized in that: It includes a base (1) and a mounting platform (2). A cylinder (4) and a parallel gripper (5) are fixedly connected on the base (1). The cylinder (4) is located above the parallel gripper (5). The mounting platform (2) is used to support the mounting body (3) and is fixedly connected to the base (1). The mounting platform (2) is located between the cylinder (4) and the parallel gripper (5). The mounting body (3) has pole pieces (31) protruding from the bottom of the mounting body (3) on both sides, and the protruding part is an extension (311). The telescopic end of the cylinder (4) has a pressure block (42) that abuts against the electrode (31). The parallel gripper (5) has two fingers (51) that move away from or towards each other simultaneously. The top of each finger (51) has a guide surface (511) that slopes upward and a horizontal surface (512) that is horizontal. The guide surface (511) faces outward. When the electrode (31) is inserted into the mounting slot (302), the extension (311) is bent once under the support of the guide surface (511). When the finger (51) moves outward, the horizontal surface (512) bends the extension (311) a second time.

2. The battery electrode bending fixture according to claim 1, characterized in that: The cylinder (4) has an actuating end (41) that slides up and down. The actuating end (41) is fixedly connected to the top of the pressure block (42). Both sides of the bottom of the pressure block (42) have arc-shaped parts (421) that match the bending of the upper end of the battery electrode (31).

3. The battery electrode bending fixture according to claim 2, characterized in that: The material of the pressure block (42) is stainless steel.

4. The battery electrode bending fixture according to claim 2, characterized in that: The mounting body (3) has through battery slots (301) on both sides, the electrode (31) is located inside the battery slot (301), and the arc-shaped part (421) is located directly above the battery slot (301).

5. The battery electrode bending fixture according to claim 4, characterized in that: The electrode (31) has an upwardly extending abutment (312) on one side, the root of which is elastic, and the abutment (312) is configured to abut against the wall of the mounting groove (302) when the electrode (31) enters the mounting groove (302).

6. The battery electrode bending fixture according to claim 1, characterized in that: A gap (6) is formed between the bottom of the mounting body (3) and the top of the finger (51) for the extension (311) to pass through, the height of the gap (6) being greater than the thickness of the extension (311).

7. The battery electrode bending fixture according to claim 1, characterized in that: The installation platform (2) has a hollow part (201) and a limiting block (21) around the hollow part (201). The installation body (3) is located inside the limiting block (21) and is partially supported by the installation platform (2) between the hollow part (201) and the limiting block (21).

8. A method for bending battery electrode sheets using a fixture as described in any one of claims 1-7, characterized in that: Includes the following steps: Step 1: Place the device into the installation platform and adjust the finger position; Step 2: Insert the battery electrode and lower the pressure block to bend the extension once; Step 3: Move your fingers outward to bend the extension a second time; Step 4: After bending, reset each component.

Images