Adsorption Component for Stacking Lithium Batteries, Auxiliary Tooling for Stacking Lithium Batteries, and Stacking Method

Abstract

An adsorption component for lithium battery stacking, an auxiliary tooling for lithium battery stacking, and a stacking method. The auxiliary tooling for lithium battery stacking includes a suction cup and a suction cup seat. The suction cup seat includes a cylinder body and a fixture. There is a support shaft in the middle of the cylinder body. The middle of the connecting rod is slidably inserted into the middle of the support shaft. There is a telescopic element between the upper end of the connecting rod and the bottom of the cylinder body of the cylinder. The lower end of the connecting rod is connected to the suction cup. There are suction cup ventilation holes on the suction cup. The lower end opening of the cylinder body is an open structure. There is an air inlet on the side wall of the cylinder body above the support shaft. There is a mounting hole on the fixture. The lower part of the mounting hole is a receiving chamber for accommodating the suction cup. The suction cup is in clearance fit with the receiving chamber. The gap between the connecting rod and the support shaft forms a transition channel. The transition channel, the inner cavity of the lower part of the support shaft, and the gap between the suction cup at the opening and the receiving chamber communicate to form a gas channel. An air outlet channel is formed between the bottom surface of the fixture and the electrode sheet. The present invention can effectively eliminate the imprints caused by the negative pressure suction cup on the electrode sheet and prevent the accumulation and blockage of dust in the vacuum pipeline.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium-ion batteries, and specifically relates to an adsorption component for lithium battery lamination, an auxiliary tooling for lithium battery lamination, and a lamination method. Background Art

[0002] A lithium-ion battery is an energy storage device with lithium-ion compounds such as lithium nickel cobalt manganese oxide and lithium iron phosphate as the positive electrode, graphite as the negative electrode, and a microporous separator in the middle. It has the advantages of high energy density, long service life, wide temperature adaptability, and good rate performance. It has been increasingly widely used in power systems, energy storage systems, wind and solar power generation, emergency power supplies, etc. According to the assembly process, lithium batteries are usually divided into two manufacturing methods: winding type and lamination type. Among them, the laminated lithium battery has the advantages of good electrode sheet adhesion, high space utilization rate, uniform internal interface reaction, good consistency, and high energy density. It has been widely used in the field of passenger cars with high requirements for battery safety performance and rate performance. With the increasing market requirements for battery consistency, the optimization of the lamination process is imminent.

[0003] The existing lithium battery lamination technology usually is that the positive and negative electrode sheets are respectively sucked onto the lamination platform by a negative pressure suction cup connected by a robotic arm, with a separator between the positive and negative electrode sheets. After multiple stackings, a bare battery cell is assembled. The negative pressure suction cup is as Figure 1 shown. However, after sucking the electrode sheet through the suction nozzle on the suction cup, usually a convex mark of the same size as the suction nozzle will be left on the electrode sheet. This convex mark is not in the same plane as the normal electrode sheet plane. This will cause an imprint of the same size on the aluminum-plastic film during the subsequent vacuum packaging process, having an adverse effect on the battery appearance. Since the convex mark does not fit well with the normal electrode sheet, during the use of the battery, the convex mark part is extremely prone to risks such as insufficient reaction, an insufficiently dense SEI film formation, lithium deposition, and even local failure, seriously affecting the safety and consistency of the battery; at the same time, due to negative pressure suction, the dust on the electrode sheet will be sucked into the vacuum pipeline. As the dust accumulates, the vacuum degree in the pipeline will decrease or even be blocked, resulting in a decrease in the suction force and even the phenomenon that the electrode sheet cannot be sucked up. Summary of the Invention

[0004] Aiming at the deficiencies of the existing lamination type electrode sheet suction method, the present invention provides an adsorption component for lithium battery lamination and an auxiliary tooling for lithium battery lamination, which can effectively eliminate the imprint caused by the negative pressure suction cup on the electrode sheet, reduce the problems of poor battery appearance and poor consistency, quickly clean the dust on the surface of the electrode sheet, and completely prevent the accumulation and blockage of dust in the vacuum pipeline.

[0005] Another object of the present invention is to provide a lithium battery lamination method.

[0006] The technical solution of the present invention is: an adsorption component for lithium battery stacking, including a suction cup and a suction cup seat. The suction cup seat includes a cylinder body. There is a support shaft in the middle of the cylinder body. The middle part of the connecting rod is slidably inserted into the middle part of the support shaft. There is a telescopic element between the upper end of the connecting rod and the bottom of the cylinder body of the cylinder. The lower end of the connecting rod is connected to the suction cup. There are suction cup ventilation holes on the suction cup. The lower end opening of the cylinder body is an open structure. There is an air inlet connected to compressed air on the side wall of the cylinder body above the support shaft. When compressed air is introduced into the inner cavity of the upper part of the support shaft from the air inlet, the gap between the connecting rod and the support shaft forms a transition channel for compressed air, and the compressed air in the inner cavity of the upper part of the support shaft flows to the opening through the transition channel.

[0007] An auxiliary tooling for lithium battery stacking, including a suction cup and a suction cup seat. The suction cup seat includes a cylinder body and a fixture. There is a support shaft in the middle of the cylinder body. The middle part of the connecting rod is slidably inserted into the middle part of the support shaft. There is a telescopic element between the upper end of the connecting rod and the bottom of the cylinder body of the cylinder. The lower end of the connecting rod is connected to the suction cup. There are suction cup ventilation holes on the suction cup. The lower end opening of the cylinder body is an open structure. There is an air inlet connected to compressed air on the side wall of the cylinder body above the support shaft. There is a mounting hole on the fixture that matches the cylinder body. The lower part of the mounting hole is a receiving chamber for accommodating the suction cup. The suction cup is in clearance fit with the receiving chamber. When the telescopic element is in a natural stress state, the bottom surface of the suction cup is higher than the fixture.

[0008] The gap between the connecting rod and the support shaft forms a transition channel for compressed air. The transition channel, the inner cavity of the lower part of the support shaft, and the gap between the suction cup at the opening and the receiving chamber are connected to form a gas channel. The bottom surface of the fixture and the pole piece form an air outlet channel. When compressed air is introduced into the inner cavity of the upper part of the support shaft from the air inlet, the compressed air flows out through the gas channel and the air outlet channel. The lower port of the gas channel is the air outlet. The compressed air in the inner cavity of the upper part of the support shaft flows to the inner cavity of the lower part of the support shaft through the transition channel, and then flows out through the gap between the suction cup and the receiving chamber at the opening.

[0009] The bottom surface of the fixture has a tooling bottom plate, and the tooling bottom plate is made of Teflon material.

[0010] A stop block is installed under the tooling bottom plate.

[0011] The cylinder body is a metal sleeve, and the connecting rod is a metal connecting rod. The suction cup is made of silicone, nitrile rubber, styrene-butadiene rubber, or fluororubber. The reason for using metal materials is that the sliding between the metal connecting rod and the support shaft is relatively smooth, with little wear and good stability.

[0012] There is a sliding hole on the middle part of the support shaft that matches the connecting rod, and there are ventilation slits at the support shaft around the sliding hole.

[0013] The telescopic element is a spring or a cylinder.

[0014] A method for lithium battery stacking

[0015] When not in operation, the spring is in its natural stress state, and the bottom surface of the suction cup is 0.5 - 1.5 mm higher than the tooling base plate;

[0016] When in operation, it includes the following steps:

[0017] First, move the auxiliary tooling for stacking lithium batteries to a position 15 - 20 mm above the electrode sheet, and introduce compressed air with a pressure of 0.1 - 0.2 MPa at the air inlet. Under the action of the compressed air, the edge of the suction cup bends. At this time, the air flow sprays onto the electrode sheet from the air outlet at the lower port of the gas channel at an angle a with the horizontal plane, and cleans the dust on the electrode sheet; a = 45 ± 10°;

[0018] Lower the auxiliary tooling for stacking lithium batteries to a position 4 - 6 mm above the electrode sheet, and adjust the air pressure at the air inlet to 0.4 - 0.5 MPa. At this time, the suction cup drives the spring to move downward under the action of the air pressure, and the high-speed gas sprays out from the air outlet channel. Due to the Bernoulli principle, a low-pressure area is formed between the tooling base plate and the electrode sheet, sucking the electrode sheet onto the suction cup;

[0019] Due to the adsorption of the electrode sheet, the edge of the silicone suction cup will attach to the electrode sheet and tend to be horizontal. At this time, the air flow will diffuse horizontally in all directions. While the horizontal air flow forms a low pressure, it cleans the dust on the edge of the electrode sheet; there are ventilation holes on the suction cup to prevent a vacuum from being generated between the suction cup and the electrode sheet when sucking the electrode sheet, causing imprints on the electrode sheet;

[0020] Move the auxiliary tooling for stacking lithium batteries to the stacking platform, and close the compressed air at the air inlet. At this time, the low-pressure area will disappear, and at the same time, the suction cup moves upward under the action of the spring. When the edge of the suction cup moves inside the tooling base plate, the electrode sheet is blocked by the tooling base plate and thus falls onto the stacking platform;

[0021] Repeat the above steps for the positive electrode sheet and the negative electrode sheet respectively to complete the production of the stacked battery cell.

[0022] The spring is replaced by a cylinder.

[0023] The features of the present invention are as follows:

[0024] 1. The metal connecting rod is connected to the spring, and the up and down position of the suction cup can be controlled by controlling the size of the air flow. In the absence of air flow, the bottom surface of the suction cup is 1 mm higher than the tooling base plate, preventing it from being contaminated by dust.

[0025] 2. The suction cup is made of silicone material, having certain strength and flexibility. Its edge can bend under the action of the air flow to control the air outlet direction by itself. The function of the bent edge is that it can bend downward under the impact of the air flow, guiding the air flow to spray downward, thereby removing the dust on the surface of the electrode sheet.

[0026] 3. The suction cup has ventilation holes to prevent the formation of a vacuum between the suction cup and the electrode plate during suction, which may cause imprints on the electrode plate. If there are no ventilation holes, when the electrode plate is sucked up, a negative pressure area may be formed between the electrode plate and the suction cup (because the suction cup is made of deformable material). When the electrode plate is put down again, imprints of the suction cup may be formed on the surface of the electrode plate. In the present invention, the suction cup is similar to an air flow guiding device and is not used as the main adsorption device.

[0027] 4. The bottom plate of the tooling is coated with Teflon material to further reduce the friction with the electrode plate.

[0028] 5. The suction cup is made of other types of rubber materials such as nitrile rubber, styrene-butadiene rubber, and fluororubber.

[0029] 6. The spring is replaced by a cylinder.

[0030] 7. Blocks are added to the bottom surface of the fixture to prevent the electrode plate from directly contacting the bottom surface. Description of the Drawings

[0031] Figure 1 is a schematic structural diagram of the prior art;

[0032] Figure 2 is a schematic structural diagram of the present invention;

[0033] Figure 3 is one of the working state diagrams of the present invention;

[0034] Figure 4 is the second working state diagram of the present invention;

[0035] Figure 5 is a schematic diagram of the block installation. Embodiment

[0036] Figure 2-5 In the embodiment, the present invention includes a suction cup 25 and a suction cup seat. The suction cup seat includes a cylinder body 21 and a fixture 31. There is a support shaft 24 in the middle of the cylinder body. The middle part of the connecting rod 23 is slidably inserted into the middle of the support shaft. An expansion element is provided between the upper end of the connecting rod and the bottom of the cylinder body of the cylinder body. The lower end of the connecting rod 23 is connected to the suction cup 25. There is a suction cup ventilation hole 251 on the suction cup 25. The lower end opening of the cylinder body is an open structure. There is an air inlet on the side wall of the cylinder body above the support shaft, which is connected to compressed air (i.e., the positive pressure air source 11). There is a mounting hole on the fixture 31 that matches the cylinder body. The lower part of the mounting hole is a receiving chamber for accommodating the suction cup 25. The suction cup 25 is in clearance fit with the receiving chamber. When the expansion element is in a natural stress state, the bottom surface of the suction cup 25 is higher than the fixture.

[0037] The gap between the connecting rod 23 and the support shaft forms a transition channel for compressed air. The transition channel, the inner cavity of the lower part of the support shaft, and the gaps between the barrel mouth suction cup 25 and the accommodating chamber are connected to form a gas channel. An air outlet channel is formed between the bottom surface of the fixture 31 and the pole piece. When compressed air is introduced into the inner cavity of the upper part of the support shaft from the air inlet, the compressed air flows out through the gas channel and the air outlet channel, and the lower port of the gas channel is the air outlet.

[0038] There is a tooling bottom plate 32 on the bottom surface of the fixture. The tooling bottom plate 32 is made of Teflon material. A stop block 33 is installed below the tooling bottom plate 32.

[0039] A method for stacking lithium battery sheets

[0040] 1. When not working, the spring 22 is in a natural stress state, and the bottom surface of the suction cup 25 is 1 mm higher than the tooling bottom plate, as Figure 2 shown.

[0041] 2. When working, first move the tooling to a position 15 - 20 mm above the pole piece, and introduce 0.1 - 0.2 MPa of compressed air into the air inlet. Under the action of the compressed air, the edge of the suction cup 25 bends slightly. At this time, the air flow sprays onto the pole piece from the air outlet at the lower port of the gas channel at an angle of 45° to the horizontal plane, and the dust on the pole piece is cleaned up, as Figure 3 shown.

[0042] 3. Lower the tooling to about 5 mm above the pole piece, and adjust the air pressure at the air inlet to 0.4 - 0.5 MPa. At this time, the suction cup 25 drives the spring 22 to move downward under the action of the air pressure, and high-speed gas sprays out from the air outlet channel. Due to the Bernoulli principle, a low-pressure area will be formed between the tooling bottom plate 32 and the pole piece 41, and the pole piece 41 is sucked onto the suction cup 25, as Figure 4 shown.

[0043] 4. Due to the adsorption of the pole piece 41, the edge of the suction cup 25 will adhere to the pole piece 41 and tend to be horizontal. At this time, the air flow will spread around horizontally along the air outlet directions 12 and 13. While the horizontal air flow forms a low pressure, it can also clean the dust on the edge of the pole piece 41, as Figure 4 shown.

[0044] 5. Move the tooling to the stacking platform, and close the compressed air at the air inlet. At this time, the low-pressure area will disappear, and at the same time, the suction cup 25 moves upward under the action of the spring 22. When the edge of the suction cup 25 moves inside the tooling bottom plate 32, the pole piece 41 is blocked by the tooling bottom plate 32 and thus falls onto the stacking platform.

[0045] 6. Repeat the above steps for the positive and negative pole pieces respectively to complete the production of the stacked battery core.

Claims

1. An auxiliary tooling for stacking lithium batteries, characterized in that: It includes a suction cup (25) and a suction cup seat. The suction cup seat includes a cylinder body and a fixture (31); there is a support shaft in the middle of the cylinder body, the middle of the connecting rod (23) is slidably inserted in the middle of the support shaft, a telescopic element is provided between the upper end of the connecting rod and the bottom of the cylinder body of the cylinder body, the lower end of the connecting rod (23) is connected to the suction cup (25), there are suction cup ventilation holes (251) on the suction cup (25), and the lower end opening of the cylinder body is an open structure; there is an air inlet connected to compressed air on the side wall of the cylinder body above the support shaft; the fixture (31) has a mounting hole that matches the cylinder body, and the lower part of the mounting hole is a receiving chamber for accommodating the suction cup (25), and the suction cup (25) is in clearance fit with the receiving chamber; when the telescopic element is in a natural stress state, the bottom surface of the suction cup (25) is higher than the fixture; The gap between the connecting rod (23) and the support shaft forms a transition channel for compressed air. The transition channel, the inner cavity of the lower part of the support shaft, and the gap between the suction cup (25) and the receiving chamber are connected to form a gas channel, and an air outlet channel is formed between the bottom surface of the fixture (31) and the pole piece; when compressed air is introduced into the inner cavity of the upper part of the support shaft from the air inlet, the compressed air flows out through the gas channel and the air outlet channel, and the lower port of the gas channel is the air outlet; there is a tooling bottom plate (32) on the bottom surface of the fixture; there is a sliding hole on the middle part of the support shaft that matches the connecting rod (23), and there are ventilation slits at the support shaft around the sliding hole; the telescopic element is a spring (22) or a cylinder.

2. The auxiliary tooling for lithium battery stacking according to claim 1, characterized in that: The tooling bottom plate (32) is made of Teflon material.

3. The auxiliary tooling for lithium battery stacking according to claim 1, characterized in that: A stop block (33) is installed below the tooling bottom plate (32).

4. The auxiliary tooling for lithium battery stacking according to claim 1, wherein: The cylinder body (21) is a metal sleeve, and the connecting rod is a metal connecting rod; the suction cup (25) is made of silica gel, nitrile rubber, styrene-butadiene rubber or fluororubber.

5. A method for stacking lithium battery laminations, which uses the auxiliary tooling for stacking lithium batteries as described in any one of claims 1-4, and is characterized in that: When not working, the spring (22) is in a natural stress state, and the bottom surface of the suction cup (25) is 0.5-1.5 mm higher than the tooling bottom plate; When working, it includes the following steps: First, move the auxiliary tooling for stacking lithium battery laminations to 15-20 mm above the pole piece, and introduce 0.1-0.2 MPa of compressed air into the air inlet. Under the action of the compressed air, the edge of the suction cup bends. At this time, the air flow sprays onto the pole piece from the air outlet at the lower port of the gas channel at an angle a with the horizontal plane, and the dust on the pole piece is cleaned; Lower the auxiliary tooling for stacking lithium battery laminations to 4-6 mm above the pole piece, and adjust the air pressure at the air inlet to 0.4-0.5 MPa. At this time, the suction cup (25) drives the spring (22) to move downward under the action of the air pressure, and the high-speed gas sprays out from the air outlet channel. Due to the Bernoulli principle, a low-pressure area is formed between the tooling bottom plate (32) and the pole piece (41), and the pole piece (41) is sucked onto the suction cup (25); Due to the adsorption of the pole piece, the edge of the suction cup will adhere to the pole piece and tend to be horizontal. At this time, the air flow will diffuse horizontally in all directions. While the horizontal air flow forms a low pressure, it cleans the dust at the edge of the pole piece; there are suction cup ventilation holes (251) on the suction cup (25) to prevent a vacuum from being generated between the suction cup and the pole piece when sucking the pole piece, causing imprints on the pole piece; Move the auxiliary tooling for lithium battery stacking to the stacking platform, and close the compressed air at the air inlet. At this time, the low-pressure area will disappear, and at the same time, the suction cup (25) will move upward under the action of the spring (22). When the edge of the suction cup (25) moves inside the tooling bottom plate (32), the electrode sheet (41) is blocked by the tooling bottom plate (32) and thus falls onto the stacking platform; Repeat the above steps for the positive electrode sheet and the negative electrode sheet respectively to complete the production of the stacked battery cell.

6. The lithium battery laminating method according to claim 5, wherein: The spring (22) is replaced by a cylinder.

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