Coating gasket for battery pole piece production

Abstract

The utility model discloses a coating gasket for producing a battery pole piece, which comprises a first gasket, the first gasket is provided with a plurality of first coating areas and a plurality of second coating areas, and the first coating areas and the second coating areas are adjacent and alternately arranged; a separation strip capable of generating elastic deformation after being extruded is arranged between the first coating area and the second coating area. According to the utility model, the first coating area and the second coating area are arranged on the first gasket at the same time, so that the pole piece with a complete coating layer and alternating coating layers and blank areas can be obtained at the same time; meanwhile, the separation strip which can generate elastic deformation when being extruded is used between the first coating area and the second coating area, and the elastic deformation characteristic of the separation strip allows finer pressure adjustment, so that more accurate coating weight control is realized. In addition, different coating modes can be realized without frequently replacing the gasket, so that the downtime in production is obviously reduced, and the production efficiency of the pole piece is improved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to lithium ion battery production technical field especially relates to a coating gasket for battery pole piece production. BACKGROUND

[0002] Lithium ion batteries are the core components of modern energy storage systems, and their production processes directly affect the performance and safety of the batteries. In the production process of lithium ion batteries, the coating of the pole piece is a critical step that not only determines the capacity and power characteristics of the battery but also affects the consistency and reliability of the battery.

[0003] In traditional pole piece coating processes, a tab area is usually reserved at the head of the battery cell pole piece for welding the tab. This coating method achieves the division of the coating area and the blank area by installing a gasket in the die head and controlling the coating of the die head. However, with the continuous advancement of battery technology and the increasing demand for high-performance batteries in the market, this traditional coating method has been unable to meet the current technical requirements.

[0004] To reduce the internal resistance of the battery cell and improve its performance and safety, some manufacturers have begun to try to place the tab area in the middle of the pole piece. Although this design improves the performance of the battery in some ways, it also brings new challenges. The large area of blank area in the middle of the pole piece cannot be fully utilized, which leads to a decrease in the energy density of the battery cell and affects the overall performance of the battery.

[0005] To address this issue, the inventors have previously developed a new coating method, such as using a double-chamber coating die head for coating. This method can effectively reduce the tab area and fully utilize the pole piece area, thereby improving the energy density of the battery cell. However, this coating method still has some shortcomings in controlling the coating amount. Specifically, this coating method controls the size of the coating amount by adjusting the gap between the pressure block and the gasket groove with a micrometer; the larger the gap, the greater the flow of electrode slurry; the smaller the gap, the smaller the flow of electrode slurry. However, the existing gaskets are generally made of steel with a uniform thickness, and when the pressure block acts on the partition strip of the gasket, the gap between the pressure block and the gasket groove cannot be further adjusted due to the thickness of the partition strip, which further prevents the accurate adjustment of the coating amount.

[0006] This limitation not only affects the flexibility of the coating process but also may lead to uneven distribution of electrode materials, which further affects the performance consistency of the battery. In large-scale production, this slight inconsistency may accumulate into significant quality differences, affecting the performance and reliability of the entire batch of batteries.

[0007] Furthermore, as new electrode materials are continuously developed and applied, the precision control requirements for the coating process are also increasing. For example, certain high-capacity electrode materials can require more precise or thinner thickness control, or different coating thicknesses in different areas of the electrode sheet to optimize battery performance. Existing coating shim structures are difficult to meet these increasing fine-tuning needs.

[0008] Another issue of concern is the efficiency and cost of the coating process. Existing coating methods can require frequent replacement or adjustment of the shim, which not only increases production time but also increases production costs.

[0009] Therefore, it is an urgent need in the industry to develop a new type of coating shim structure that can quickly and accurately adjust the coating amount while taking into account production efficiency. Invention content

[0010] The purpose of the present application is to address the shortcomings of the prior art and provide a coating shim for battery electrode sheet production that can quickly and accurately adjust the coating amount while taking into account production efficiency.

[0011] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0012] A coating shim for battery electrode sheet production, comprising a first shim, the first shim is provided with a plurality of first coating areas and a plurality of second coating areas, the first coating areas and the second coating areas are adjacent and alternately arranged; a separation strip that can produce elastic deformation when extruded is arranged between the first coating areas and the second coating areas.

[0013] When the first coating area is coated, continuous coating is adopted, and an electrode sheet with a complete coating layer can be obtained; when the second coating area is coated, intermittent coating is adopted, and an electrode sheet with alternating coating layers and blank areas can be obtained.

[0014] Preferably, the separation strip is elastic silicone or elastic rubber.

[0015] Preferably, the first coating area is provided with a plurality of reinforcing ribs, and the plurality of reinforcing ribs are evenly arranged along the first coating area.

[0016] Preferably, the length of the first coating area is greater than the length of the second coating area.

[0017] Preferably, the first coating area has a shape of being wider in front and narrower at the back along the longitudinal direction, and the second coating area has a shape of being narrower in front and wider at the back along the longitudinal direction.

[0018] Preferably, the bottom height of the first coating area is lower than the bottom height of the second coating area.

[0019] Preferably, the coating pad further comprises a second pad arranged in a stack with the first pad, the second pad is respectively provided with a first opening and a second opening, the first opening corresponds to the bottom of the first coating area, and the second opening corresponds to the bottom of the second coating area.

[0020] Preferably, the length of the first opening is matched with the length of the first coating area, and the length of the second opening is matched with the length of the second coating area.

[0021] Preferably, the opening area of the first opening is greater than the opening area of the second opening.

[0022] Preferably, the top of the separation strip is a sharp corner structure, and the upper edge of the separation strip is 0.1-2.5mm lower than the upper edge of the second pad. That is, the upper edge of the separation strip does not exceed the upper edge of the second pad, and the distance between the upper edge of the separation strip and the upper edge of the second pad is 0.1-2.5mm.

[0023] Preferably, the first pad is provided with a plurality of first fixing holes, the second pad is provided with a plurality of second fixing holes, and the first fixing holes correspond to the second fixing holes.

[0024] Compared with the prior art, the utility model has at least the following beneficial effects:

[0025] 1) The first coating area and the second coating area are arranged in the first pad simultaneously, when the first coating area is coated, continuous coating is adopted, and a pole piece with a complete coating layer can be obtained, when the second coating area is coated, intermittent coating is adopted, and a pole piece with a coating layer and a blank area alternately can be obtained.

[0026] 2) The separation strip which can be elastically deformed by extrusion is used between the first coating area and the second coating area, so that the gap between the two can become smaller by extruding the elastic separation strip, therefore, the elastic deformation characteristics of the separation strip allow more precise pressure adjustment, so that more accurate coating amount control is realized. In addition, different coating modes can be realized without frequent replacement of the pad, which significantly reduces the downtime in production and improves the production efficiency of the pole piece. BRIEF DESCRIPTION OF DRAWINGS

[0027] Fig. 1 It is a structure schematic view of the first pad of the coating pad of an embodiment of the utility model;

[0028] Fig. 2 It is a structure schematic view of the second pad of the coating pad of an embodiment of the utility model;

[0029] Fig. 3The first gasket and the second gasket of the coating gasket according to an embodiment of the present application are stacked.

[0030] In the figure: 1, first gasket; 11, first coating area; 12, second coating area; 13, separation strip; 14, reinforcing rib; 15, first fixing hole; 2, second gasket; 21, first opening; 22, second opening; 23, second fixing hole. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be apparently and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0032] Please refer to the drawings Figs. 1-3 The coating gasket for battery pole piece production provided in the present application comprises a first gasket 1, the first gasket 1 is provided with a plurality of first coating areas 11 and a plurality of second coating areas 12, the first coating areas 11 and the second coating areas 12 are adjacent and alternately arranged; a separation strip 13 capable of being elastically deformed by extrusion is arranged between the first coating areas 11 and the second coating areas 12.

[0033] Among them, the first coating area 11 and the second coating area 12 are arranged on the first gasket 1 at the same time; when the first coating area 11 is coated, continuous coating is adopted, so that a pole piece with a complete coating layer can be obtained; when the second coating area 12 is coated, intermittent (jump gap) coating is adopted, so that a pole piece with a coating layer and a blank area alternately arranged can be obtained.

[0034] In addition, the separation strip 13 capable of being elastically deformed by extrusion is used between the first coating area 11 and the second coating area 12, so that the gap between the two can become smaller by extruding the elastic separation strip 13, and therefore the elastic deformation characteristics of the separation strip 13 allow more precise pressure adjustment, so as to realize more accurate coating amount control.

[0035] The first gasket 1 of the embodiment includes a gasket body and a partition strip 13. The gasket body is generally made of steel material. In order to enable the partition strip 13 to be elastically deformed by being partially extruded, the partition strip 13 is made of an elastic material. The end of the elastic partition strip 13 is fixedly connected to the gasket body by clamping or bonding. For example, a clamping protrusion is arranged at the position of the gasket body corresponding to the partition strip 13. The end of the elastic partition strip 13 is provided with a groove. The partition strip 13 is fixed to the gasket body by the concave-convex matching mode. Of course, other fixing modes can also be used to fixedly connect the elastic partition strip 13 to the gasket body.

[0036] In an embodiment according to the application, the first gasket 1 is entirely made of an elastic material. In this way, the first gasket 1 is integrally formed by injection molding. This facilitates production and processing and meets the elastic deformation requirement.

[0037] In an embodiment according to the application, the partition strip 13 is made of an elastic material such as elastic silica gel or elastic rubber, preferably ethylene-propylene-diene rubber. These materials have good elasticity and durability and can maintain stable performance in long-term use, ensuring the consistency and reliability of the coating amount adjustment. It should be noted that other materials capable of elastic deformation can also be used.

[0038] In an embodiment according to the application, the first coating area 11 is provided with a plurality of reinforcing ribs 14. The reinforcing ribs 14 are uniformly arranged along the first coating area 11. The uniformly distributed reinforcing ribs 14 enhance the structural strength of the first coating area 11, prevent deformation under high pressure, and ensure the uniformity and stability of the coating.

[0039] In an embodiment according to the application, the length of the first coating area 11 is greater than the length of the second coating area 12. In this way, the area ratio of the complete coating layer of the pole piece can be larger, and the energy density of the pole piece and the battery cell can be improved.

[0040] In an embodiment according to the application, the first coating area 11 has a shape of being wider in front and narrower at the back along the longitudinal direction, and the second coating area 12 has a shape of being narrower in front and wider at the back along the longitudinal direction. In this way, the slurry flow of the two coating areas can be better controlled. It should be noted that the first coating area 11 and the second coating area 12 can be adjusted in width and narrowness in front and back according to actual needs to control the coating flow.

[0041] In an embodiment according to the present application, the bottom of the first coating area 11 is lower than the bottom of the second coating area 12. Since the first coating area 11 is used for coating continuous coating layers, and the second coating area 12 is used for coating intermittent coating layers (coating layers and blank areas are alternated), the coating height of the two different areas can be controlled to facilitate the control of the blank area. It should be noted that the first coating area 11 and the second coating area 12 can also be used reversely during coating; that is, the first coating area 11 is used for coating intermittent coating layers (coating layers and blank areas are alternated), and the second coating area 12 is used for coating continuous coating layers.

[0042] In an embodiment according to the present application, the coating spacer further comprises a second spacer 2 stacked with the first spacer 1, and the second spacer 2 is respectively provided with a first opening 21 and a second opening 22, the first opening 21 corresponds to the bottom of the first coating area 11, and the second opening 22 corresponds to the bottom of the second coating area 12. The first opening 21 is connected to the first material cavity of the coating die, and is used for guiding the slurry to the first coating area 11 of the first spacer 1; the second opening 22 is connected to the second material cavity of the coating die, and is used for guiding the slurry to the second coating area 12 of the first spacer 1.

[0043] In an embodiment according to the present application, the length of the first opening 21 is adapted to the length of the first coating area 11, and the length of the second opening 22 is adapted to the length of the second coating area 12; the uniformity of the coating slurry introduced into the first coating area 11 and the second coating area 12 can be ensured.

[0044] In an embodiment according to the present application, the opening area of the first opening 21 is larger than the opening area of the second opening 22. During coating, the first coating area 11 coats a larger area, so a larger feeding space is required; the second coating area 12 coats a smaller area, so a slightly smaller feeding space can be used.

[0045] In an embodiment according to the present application, the top of the separation strip 13 is a sharp corner structure, and the upper edge of the separation strip 13 is 0.1-2.5mm lower than the upper edge of the second spacer 2. In this way, the slurry on both sides of the separation strip 13 (two coating areas) can be better fused at the joint, preventing uneven coating thickness at the joint.

[0046] In an embodiment according to the present application, the first spacer 1 is provided with a plurality of first fixing holes 15, the second spacer 2 is provided with a plurality of second fixing holes 23, and the first fixing holes 15 correspond to the second fixing holes 23; the fixing and assembly of the two spacers can be quickly realized, the accurate alignment of the two spacers is ensured, and the precision and consistency of coating are improved.

[0047] The coated gasket of the present application is used by placing the gasket between the upper die and the lower die of the double-cavity coating die; wherein the first opening 21 is connected to one of the cavities of the coating die for guiding the slurry to the first coating area 11 of the first gasket 1; the second opening 22 is connected to the other cavity of the coating die for guiding the slurry to the second coating area 12 of the first gasket 1. When the first coating area 11 is coated, continuous coating is adopted to obtain a pole piece with a complete coating layer; when the second coating area 12 is coated, intermittent coating is adopted to obtain a pole piece with coating layers and blank areas alternating.

[0048] It should be noted that the contents not described in detail in the specification belong to the prior art known to those skilled in the art, which will not be described here.

[0049] According to the disclosure and teaching of the above description, those skilled in the art of the present application can also make changes and modifications to the above embodiments. Therefore, the present application is not limited to the above specific embodiments, and any obvious improvements, replacements or modifications made by those skilled in the art on the basis of the present application all belong to the protection scope of the present application. In addition, although some specific terms are used in the specification, these terms are only for convenience of description and do not constitute any limitation on the present application.

Claims

1. A coating shim for battery electrode sheet production, characterized by: The first gasket is provided with a plurality of first coating areas and a plurality of second coating areas, the first coating areas are adjacent to and alternately arranged with the second coating areas; and a partition strip is arranged between the first coating areas and the second coating areas, and the partition strip can be elastically deformed by being extruded.

2. The coating shim for battery electrode sheet production according to claim 1, characterized by: The partition strip is made of elastic silica gel or elastic rubber.

3. The coating shim for battery electrode sheet production according to claim 1, characterized by: The first coating area is provided with a plurality of reinforcing ribs, and the reinforcing ribs are uniformly arranged along the first coating area.

4. The coating shim for battery electrode sheet production according to claim 1, characterized by: The length of the first coating area is greater than the length of the second coating area.

5. The coating shim for battery electrode sheet production according to claim 1, characterized by: The bottom height of the first coating area is lower than the bottom height of the second coating area.

6. The coating shim for battery electrode sheet production according to any one of claims 1 to 5, characterized by: The second gasket is arranged in a stack with the first gasket, the second gasket is respectively provided with a first opening and a second opening, the first opening corresponds to the bottom of the first coating area, and the second opening corresponds to the bottom of the second coating area.

7. The coating shim for battery electrode production according to claim 6, characterized by: The length of the first opening is matched with the length of the first coating area, and the length of the second opening is matched with the length of the second coating area.

8. The coating shim for battery electrode sheet production according to claim 6, characterized by: The opening area of the first opening is greater than the opening area of the second opening.

9. The coating shim for battery electrode sheet production according to claim 6, characterized by: The top of the partition strip is a sharp corner structure, and the upper edge of the partition strip is 0.1-2.5 mm lower than the upper edge of the second gasket.

10. The coating shim for battery electrode sheet production according to claim 6, characterized by: The first gasket is provided with a plurality of first fixing holes, the second gasket is provided with a plurality of second fixing holes, and the first fixing holes correspond to the second fixing holes.

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