CN219112051U - Gasket, coating die head and pole piece manufacturing device - Google Patents

Abstract

The application relates to a gasket, coating die head and pole piece manufacturing installation are provided with at least a set of runner group on the gasket, and runner group includes first runner and second runner, and first runner and second runner are laid in proper order along the length direction of gasket, and first runner is used for exporting first active slurry, and second runner is used for exporting second active slurry. The gasket, the coating die head and the pole piece manufacturing device provided by the application can relieve the problem of poor compatibility of coating, thereby being capable of meeting different coating demands.

Description

Gasket, coating die head and pole piece manufacturing device

Technical Field

The application relates to the technical field of batteries, in particular to a gasket, a coating die head and a pole piece manufacturing device.

Background

The coating of the pole piece is particularly important in the manufacturing process of the battery, and in the production practice, in order to further improve the production efficiency and meet special technical requirements, the coating requirements of various sizing agents are required to be met.

At present, the most widely used coating die heads are formed by combining and constructing a plurality of flow channels by an upper die head, a lower die head and a gasket clamped between the upper die head and the lower die head, so as to achieve the aim of simultaneously coating a plurality of slurries.

The conventional coating die has poor coating compatibility, and can not coat the first active slurry and the second active slurry with different coating width ratios according to different coating requirements.

Disclosure of Invention

In view of the above, the present application provides a gasket, a coating die head, and a pole piece manufacturing apparatus, which can alleviate the problem of poor compatibility of coating, thereby being capable of meeting different coating requirements.

In a first aspect, the present application provides a gasket for pole piece coating is provided with at least a set of runner group on the gasket, and runner group includes first runner and second runner, and first runner and second runner are laid in proper order along the length direction of gasket, and first runner is used for exporting first active slurry, and second runner is used for exporting second active slurry.

In this application, because the first runner that is used for exporting first active slurry and the second runner that exports second active slurry all are located the gasket, consequently, according to the battery monomer of different kinds, can design different kinds of gaskets, the width ratio of first runner and second runner on the different kinds of gaskets is different. Therefore, according to the requirements of pole piece manufacture, the gasket with the width ratio of the first runner and the second runner is selected to be clamped between the first die head and the second die head, namely, the first active slurry and the second active slurry with the width ratio of the first runner and the second runner are output, and then the first active slurry layer and the second active slurry layer with the width ratio of the first runner and the second runner are formed by solidification, so that the requirements of pole piece manufacture are met.

In some embodiments, the gasket has a first surface and a second surface disposed opposite to each other along a thickness direction thereof, and the first flow channel is disposed on the first surface or the second surface.

Compared with the first flow passage formed in the gasket, the first flow passage is arranged on the first surface or the second surface in a simpler and easier way, and the first flow passage is convenient to form.

In some embodiments, the first flow channel is configured as a groove structure formed by a depression of the first surface or the second surface.

On the one hand, the groove structure has a good flow guiding effect, so that the first active slurry can only flow in a defined area, and the risk of mixed flow of the first active slurry and other slurries is reduced; on the other hand, the groove structure is simpler to form, and the forming efficiency of the first flow channel is improved conveniently.

In some embodiments, the first flow channel has a groove depth H ₁ The thickness of the gasket is H ₂ ，H ₁ The conditions are satisfied: 60% H ₂ ≤H ₁ ≤80％H ₂ 。

Due to H ₁ The conditions are satisfied: 60% H ₂ ≤H ₁ ≤80％H ₂ In this range, when the gasket presss from both sides and locates between first die head and the second die head, the gasket sets up the position of first runner and is difficult for taking place deformation, and can satisfy the coating demand, therefore can compromise the demand of high energy density and high coating accuracy.

In some embodiments, H ₁ The conditions are satisfied: 65% H ₂ ≤H ₁ ≤75％H ₂ 。

Under this design, first runner groove depth sets up suitably, can satisfy the demand of pole piece coating. Meanwhile, in the thickness direction of the gasket, the remaining thickness of the part where the gasket is arranged at the first flow passage is thicker, so that the risk of deformation at the part can be further reduced.

In some embodiments, the discharge end of the first flow channel is disposed to protrude from the discharge end of the second flow channel in the width direction of the gasket.

Compared with the arrangement of the discharge end of the first flow channel and the discharge end of the second flow channel which are flush (i.e. the discharge end edge of the first flow channel is flush with the discharge end edge of the second flow channel), the discharge end of the first flow channel is arranged to protrude from the discharge end of the second flow channel, so that the possibility that the first active slurry and the second active slurry are mixed is lower, and the coating accuracy is improved.

In some embodiments, the gasket has a first surface and a second surface disposed opposite each other along a thickness direction thereof;

the second flow passage is configured as a groove structure formed by recessing the first surface or the second surface, or is configured as a notch provided through the first surface and the second surface in the thickness direction of the gasket.

Through setting up first runner and being groove structure, the second runner is the breach, can promote first runner and the fashioned simplicity of second runner to the preparation degree of difficulty of gasket is reduced.

In some embodiments, the gasket has a discharge front disposed along a width thereof, and the notch has a bottom wall formed by the inward shrinkage of the discharge front; along the width direction of the gasket, the discharge end of the first flow channel is arranged to protrude from the bottom wall.

The discharge end of the first runner is arranged to protrude from the bottom wall, so that the possibility that the first active slurry and the second active slurry are mixed before flowing out of the coating die head can be reduced, and the coating accuracy can be improved.

In some embodiments, the discharge end of the first flow channel has a discharge end edge formed by the inward tapering of a discharge leading edge, the discharge leading edge and the discharge end edge of the first flow channel defining a slurry diffusion zone.

In the actual coating process, the first active slurry flowing out of the first flow channel and the second active slurry flowing out of the second flow channel can be diffused and fused in the diffusion area and then output out of the coating die head. Therefore, after coating is completed, a first active slurry layer formed by curing the first active slurry on the pole piece substrate and a second active slurry layer formed by curing the second active slurry do not have a coating gap, so that the coating effect of the battery pole piece can be effectively improved.

In some embodiments, the gasket further has a third flow passage for outputting a third slurry; the third flow channel is arranged on at least one side of each flow channel group along the length direction of the gasket.

Through setting up the third runner, the coating die head can be simultaneously coated multiple kind thick liquids to satisfy diversified coating demand, and have higher coating efficiency.

In some embodiments, each side of each flow channel group is provided with a third flow channel, and each flow channel group and the third flow channel groups arranged at two sides and adjacent to the flow channel groups form a composite flow channel group;

along the length direction of the gasket, each end of the composite runner group comprises a third runner and a first runner from outside to inside.

By arranging the composite runner groups, each end of the composite runner group comprises a third runner and a first runner from outside to inside, one die can be used for multiple out, and pole pieces with symmetrical structures can be formed by coating.

In some embodiments, in the same flow channel group, at least two first flow channels are arranged, all the first flow channels are sequentially and alternately arranged along the length direction of the gasket, and at least one second flow channel is arranged between two adjacent first flow channels.

At least two adjacent first flow channels are provided with a second flow channel, so that one-die-out is realized, and the pole pieces with symmetrical structures can be formed by coating.

In a second aspect, there is provided herein a coating die comprising:

a first die;

a second die; and

the gasket according to any one of the embodiments, wherein the gasket is clamped between the first die head and the second die head and is matched with the first die head and the second die head to form first discharge holes corresponding to the first flow passages one by one and second discharge holes corresponding to the second flow passages one by one, and the width of each first discharge hole is smaller than the width of each second discharge hole.

The width of each first discharge hole is smaller than that of each second discharge hole, and then the first active slurry layer and the second active slurry layer with different widths can be coated and formed, so that the requirements of pole piece coating are met.

In some embodiments, a first cavity and a first feed port are disposed on the first die, the first cavity being in communication between the first feed port and the first flow channel; and/or

The second die head is provided with a second cavity and a second feeding hole, and the second cavity is communicated between the second feeding hole and the second flow channel.

Through setting up first cavity, first feed inlet, second cavity and second feed inlet for first active slurry source can be through first feed inlet continuous to first cavity internal feed, and the second active slurry source can be continuous to the internal feed of second cavity, and then, the coating die head can export first active slurry and second active slurry in succession, thereby helps realizing continuous coating's purpose.

In a third aspect, the present application provides a pole piece manufacturing device, including a coating die according to any one of the embodiments above, the coating die being used for coating a pole piece substrate.

In this application, according to the battery monomer of different kinds, can design the gasket of different kinds, the width ratio of first runner on the gasket of different kinds and second runner is different. Therefore, when the coating width ratio of the first active slurry to the second active slurry on the pole piece substrate is changed, different kinds of gaskets can be replaced to be clamped between the first die head and the second die head and coated, so that the requirement of pole piece manufacturing is met.

In some embodiments, in the same channel group, at least two first channels are arranged at intervals in sequence along the length direction of the gasket, one second channel is arranged between every two adjacent first channels, the gasket is further provided with a third channel, and the opposite two sides of each channel group arranged along the length direction of the gasket are respectively provided with a third channel, and the third channels are used for outputting third slurry.

Therefore, one-die-out can be realized by arranging one second runner between every two adjacent first runners, and arranging third runners on two opposite sides of each runner group along the length direction of the gasket.

In some embodiments, the first active paste has a swelling ratio greater than that of the second active paste, and the third paste is an insulating paste.

The swelling rate of the first active slurry is larger than that of the second active slurry, the first active slurry is coated on the skived area of the pole piece substrate, and the second active slurry is coated on the non-skived area of the pole piece substrate, so that the first active slurry layer formed by solidifying the first active slurry and the second active slurry layer formed by solidifying the second active slurry are expanded after contacting electrolyte in a battery monomer, and the expanded size of the first active slurry layer in the thickness direction of the pole piece substrate is larger than that of the second active slurry layer in the thickness direction of the pole piece substrate. In this way, the expanded volume of the first active slurry layer can effectively fill the gap to enable normal lithium deintercalation. The third paste is an insulating paste, and the main purpose of the arrangement is to realize edge insulation of the pole pieces so as to reduce the risk of edge short circuit between two pole pieces with opposite polarities, which are adjacently arranged in the electrode assembly.

In some embodiments, the thickness of the region of the pole piece substrate corresponding to the first flow channel is less than the thickness of the other regions along the thickness of the pole piece.

That is, the area of the pole piece substrate coated with the first active slurry needs to be thinned. Therefore, the risk of edge bulging of the pole piece in the battery cell in the charging and discharging process can be reduced.

The foregoing description is only an overview of the technical solutions of the present application, and may be implemented according to the content of the specification in order to make the technical means of the present application more clearly understood, and in order to make the above-mentioned and other objects, features and advantages of the present application more clearly understood, the following detailed description of the present application will be given.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:

FIG. 1 is a schematic view of the overall structure of a coating die according to an embodiment of the present application;

FIG. 2 is an exploded view of the coating die shown in FIG. 1;

FIG. 3 is a schematic view of a first die of the coating die of FIG. 1;

FIG. 4 is a schematic view of a second die of the coating die of FIG. 1;

FIG. 5 is a schematic view of the structure of a shim in the coating die of FIG. 1;

FIG. 6 is a bottom view of the coating die of FIG. 1 with a first die mated with a shim;

FIG. 7 is a top view of the coating die of FIG. 1 with a second die mated with a shim;

FIG. 8 is a left side cross-sectional view of the shim in the coating die of FIG. 7;

FIG. 9 is a schematic diagram of the configuration of a coating die mated with a pole piece substrate coating roller and pole piece substrate in an embodiment of the present application;

fig. 10 is a schematic structural diagram of a pole piece manufacturing apparatus according to an embodiment of the present application.

Description of the drawings:

1000. a pole piece manufacturing device;

100. a coating die head; 200. a pole piece substrate coating roller; 300. a pole piece substrate; 400. a first active slurry layer; 500. a second active slurry layer; 600. a third slurry layer; 700. a pole piece substrate release roller; 800. a pole piece substrate wind-up roll;

10. a first die; 20. A second die; 30. A gasket;

11. a first feed port; 12. A first cavity; 13. A feed channel;

21. a second feed inlet; 22. A second cavity;

31. a flow channel group; 311. a first flow passage; 312. a second flow passage; 313. a third flow passage; 32. a slurry diffusion zone; 33. a discharging front edge; 34. a bottom wall; 35. a sidewall; 36. the first discharging end edge; 37. a first surface; 38. a second surface;

400a, a first active slurry layer; 400b, a second first active slurry layer; 400c, a third first active slurry layer;

500a, a first second active slurry layer; 500b, a first second active slurry layer;

600a, a first third slurry layer; 600b, a second third slurry layer.

Detailed Description

In order to make the above objects, features and advantages of the present application more comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. This application is, however, susceptible of embodiment in many other forms than those described herein and similar modifications can be made by those skilled in the art without departing from the spirit of the application, and therefore the application is not to be limited to the specific embodiments disclosed below.

In the description of the present application, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," etc. indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be configured and operated in a particular orientation, and therefore should not be construed as limiting the present application.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present application, the meaning of "plurality" is at least two, such as two, three, etc., unless explicitly defined otherwise.

In this application, unless specifically stated and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

In this application, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

Currently, the more widely the battery is used in view of the development of market situation. The battery is not only applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles, electric automobiles, and the like, as well as a plurality of fields such as military equipment, aerospace, and the like. With the continuous expansion of the battery application field, the market demand thereof is also continuously expanding.

A battery refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. The battery cell comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a pole piece, and the prepared pasty viscous slurry is uniformly and continuously coated on a pole piece substrate of the pole piece, such as aluminum foil or copper foil, by adopting a coating die head to form the pole piece. It should be noted that the electrode sheet mentioned in the present application may be any one of a positive electrode sheet and a negative electrode sheet. That is, the positive electrode sheet and the negative electrode sheet can be formed by coating with a coating die.

The applicant has noted that the application of multiple slurries is often involved in the manufacturing process of pole pieces, and existing coating dies often employ modifications to the structure of the upper die, lower die and gasket to form multiple flow channels capable of simultaneously applying multiple slurries. However, such coating dies have poor compatibility and can be used only for coating different pastes having a fixed coating width ratio, and it is difficult to satisfy diversified coating requirements.

Based on the above-mentioned considerations, the applicant has made intensive studies to design a gasket on which a plurality of flow channels are designed, and different kinds of flow channels can be used for coating different kinds of slurries. Meanwhile, a plurality of gaskets can be arranged, the gaskets of different types are arranged, and the width ratio of each flow channel is different. In this way, according to the requirement of diversified coating width ratios, a gasket matched with the coating requirement can be selected to be clamped between the upper die head and the lower die head, so as to realize diversification of pole piece manufacture.

Referring to fig. 1, fig. 1 is a schematic diagram illustrating an overall structure of a coating die 100 according to an embodiment of the present application. The coating die 100 disclosed herein may be used, but is not limited to, for pole piece coating, but may also be used to coat non-battery components. The following examples are each illustrated with the application die 100 used for pole piece application.

Referring to fig. 2, 3 and 4 together, fig. 2 is an exploded view of a coating die 100 according to some embodiments of the present application, fig. 3 is a schematic view of a first die 10 according to some embodiments of the present application, and fig. 4 is a schematic view of a second die 20 according to some embodiments of the present application. In some embodiments of the present application, the coating die 100 includes a first die 10, a second die 20, and a gasket 30, wherein a plurality of flow channels are provided on the gasket 30, and the gasket 30 is sandwiched between the first die 10 and the second die 20 and cooperates with the first die 10 and the second die 20 to form discharge ports corresponding to the flow channels one by one. Each slurry corresponding to each runner one by one is output from the corresponding discharge port and coated on the pole piece substrate 300 to form a pole piece.

Referring to fig. 5, fig. 5 is a schematic structural diagram of a gasket 30 according to some embodiments of the present application. In some embodiments of the present application, at least one flow channel group 31 is disposed on the gasket 30, the flow channel group 31 includes a first flow channel 311 and a second flow channel 312, the first flow channel 311 and the second flow channel 312 are sequentially disposed along a length direction X of the gasket 30, the first flow channel 311 is used for outputting a first active slurry, and the second flow channel 312 is used for outputting a second active slurry.

The number of the flow channel groups 31 on the same gasket 30 and the number of the first flow channels 311 and the second flow channels 312 in the same flow channel group 31 are not limited to one or more, and may be set according to specific production requirements. For example, a plurality of runner groups 31 are formed on the same gasket 30, and the runner groups are sequentially arranged along the length direction X of the gasket 30, so as to achieve the purpose of one-die-multiple-out.

The first flow channel 311 and the second flow channel 312 each extend in the width direction Y of the gasket 30. The specific manner of forming the first flow channel 311 and the second flow channel 312 may be various, for example, the first flow channel 311 and the second flow channel 312 may be formed by a through groove structure penetrating the gasket 30 in the thickness direction Z of the gasket 30, or may be formed by a groove structure recessed in the thickness direction Z of the gasket 30, or may be formed by a hollow flow channel structure located inside the gasket 30. The first flow channel 311 and the second flow channel 312 may be configured in the same manner or may be configured in different manners.

The first active paste and the second active paste may be designed such that there are different active pastes for silicon content, swelling ratio, etc. according to the improved performance required for the battery. For example, the first reactive slurry may be designed to have a greater silicon content than the second reactive slurry. For another example, the swelling ratio of the first active slurry may be designed to be less than the swelling ratio of the second active slurry.

Considering that the width ratio set by the first active paste layer 400 formed by the first active paste and the second active paste layer 500 formed by the second active paste on the pole piece in the different kinds of battery cells is different, and the width of the first flow channel 311 is related to the coating width of the first active paste layer 400 and the width of the second flow channel 312 is related to the coating width of the second active paste layer 500, the coating width ratio of the first active paste to the second active paste should also be changed according to the different kinds of battery cells in the coating process, so the gasket 30 in the present application is designed.

In the present application, since the first flow channel 311 for outputting the first active slurry and the second flow channel 312 for outputting the second active slurry are both located on the gasket 30, different kinds of gaskets 30 can be designed according to different kinds of battery cells, and the width ratio of the first flow channel 311 to the second flow channel 312 on the different kinds of gaskets 30 is different. For example, there is a battery cell having a pole piece with a width ratio of the first active slurry layer 400 to the second active slurry layer 500 of 1:3, the width ratio of the first flow channel 311 to the second flow channel 312 may be set to be 1:3. for another example, there is a battery cell having a pole piece with a width ratio of the first active slurry layer 400 to the first active slurry layer 400 of 1:4, the width ratio of the first flow channel 311 to the second flow channel 312 may be set to be 1:4. in this way, according to the requirements of pole piece manufacturing, the gasket 30 with the width ratio of the first runner 311 and the second runner 312 is selected to be clamped between the first die head 10 and the second die head 20, i.e. the first active slurry and the second active slurry with the width ratio being adapted can be output, and then the first active slurry layer 400 and the second active slurry layer 500 with the width ratio being adapted can be formed by curing, so as to meet the requirements of pole piece manufacturing.

In addition, since the flow channels for outputting the slurry are all arranged on the gasket 30 in a concentrated manner in the present application, the first die head 10 and the second die head 20 can be commonly used, and thus, the manufacturing difficulty of the coating die head 100 is also reduced.

Referring to fig. 6 and fig. 7 together, fig. 6 is a schematic structural diagram of the first die 10 and the gasket 30 in some embodiments of the present application, and fig. 7 is a schematic structural diagram of the second die 20 and the gasket 30 in some embodiments of the present application. In some embodiments, the gasket 30 has a first surface 37 and a second surface 38 disposed opposite to each other along a thickness direction Z thereof, and the first flow channel 311 is disposed on the first surface 37 or the second surface 38.

The first die 10 supplies the first active slurry to the first flow path 311 when the first flow path 311 is formed on the first surface 37, and the second die 20 supplies the first active slurry to the first flow path 311 when the first flow path 311 is formed on the second surface 38.

The provision of the first flow channels 311 on the first surface 37 or the second surface 38 is simpler and easier to operate than forming the first flow channels 311 on the inside of the gasket 30, facilitating the formation of the first flow channels 311.

In some embodiments of itself, the first flow channel 311 is configured as a groove structure formed by recessing the first surface 37 or the second surface 38.

That is, the first flow passage 311 may be formed by a groove structure configuration in which the first surface 37 is concavely formed, or may be formed by a groove structure configuration in which the second surface 38 is concavely formed.

On the one hand, the groove structure has a good flow guiding effect, so that the first active slurry can only flow in a defined area, and the risk of mixed flow of the first active slurry and other slurries is reduced; on the other hand, the formation of the groove structure is simpler, so that the forming efficiency of the first flow channel 311 is improved.

Referring to fig. 8, fig. 8 is a left side cross-sectional view of some embodiments of the gasket 30 according to the present invention. In some embodiments of the present application, the first flow channel 311 has a groove depth H ₁ The thickness of the gasket 30 is H ₂ ，H ₁ The conditions are satisfied: 60% H ₂ ≤H ₁ ≤80％H ₂ 。

Wherein the thickness of the spacer 30 refers to the spacing between the first surface 37 and the second surface 38. The groove depth of the first flow path 311 refers to the distance from the surface forming the first flow path 311 to the bottom wall of the groove of the first flow path 311. Taking the structure of the first flow channel 311 with the recess formed by recessing the first surface 37 as an example, the groove depth of the first flow channel 311 refers to the distance between the first surface 37 and the bottom wall of the groove of the first flow channel 311.

If the groove depth of the first flow channel 311 is too large, the remaining thickness of the gasket 30 where the first flow channel 311 is provided is small in the thickness direction Z of the gasket 30. The remaining thickness of the gasket 30 where the first flow channel 311 is provided means a difference between the thickness of the gasket 30 and the groove depth of the first flow channel 311. The spacer 30 has a smaller residual thickness at the position where the first flow channel 311 is provided, so that the position where the first flow channel 311 is provided is more easily deformed, and the first flow channel 311 may be offset or deformed, thereby reducing the coating accuracy. If the groove depth of the first flow channel 311 is too small, the first active slurry is coated thinner, and thus the requirement of high energy density of the battery cell cannot be satisfied.

In the present application, however, due to H ₁ The conditions are satisfied: 60% H ₂ ≤H ₁ ≤80％H ₂ In this range, when the gasket 30 is sandwiched between the first die 10 and the second die 20, the gasket 30 is not easily deformed at the position where the first flow passage 311 is provided, and the coating requirement can be satisfied, so that the requirements of high energy density and high coating accuracy can be satisfied.

In some embodiments of the present application, H ₁ The conditions are satisfied: 65% H ₂ ≤H ₁ ≤75％H ₂ 。

Under this design, the first runner 311 groove depth sets up suitably, can satisfy the demand of pole piece coating. At the same time, in the thickness direction Z of the gasket 30, the remaining thickness of the gasket 30 where the first flow passage 311 is provided is thicker, so that the risk of deformation at this point can be further reduced.

Referring again to fig. 5, in some embodiments of the present application, along the width direction Y of the gasket 30, the discharge end of the first flow channel 311 is disposed to protrude from the discharge end of the second flow channel 312.

The first flow channel 311 and the second flow channel 312 each have a discharge end edge disposed along the width direction Y of the gasket 30, and the discharge end edge refers to an end edge of the slurry flowing out of the flow channel. The discharge end of the first flow path 311 means an end including a discharge end edge of the first flow path 311, and the discharge end of the second flow path 312 means an end including a discharge end edge of the second flow path 312.

The gasket 30 has a discharge front 33 disposed along its width direction Y.

The discharge end edge of the first flow channel 311 is defined as a first discharge end edge 36, and the discharge end of the first flow channel 311 is arranged to protrude from the discharge end of the second flow channel 312, which may be arranged flush with the discharge front edge 33 of the gasket 30, or may also be arranged with the first discharge end edge 36 retracted relative to the discharge front edge 33 of the gasket 30, specifically, may be arranged as required.

Compared to the arrangement of the discharge end of the first flow channel 311 flush with the discharge end of the second flow channel 312 (i.e., the discharge end edge of the first flow channel 311 flush with the discharge end edge of the second flow channel 312), the discharge end of the first flow channel 311 is arranged to protrude from the discharge end of the second flow channel 312, so that the mixing possibility of the first active slurry and the second active slurry is lower, thereby helping to improve the coating accuracy.

In some embodiments of the present application, the spacer 30 has a first surface 37 and a second surface 38 disposed opposite along a thickness direction Z thereof; the second flow channel 312 is configured as a groove structure formed by recessing the first surface 37 or the second surface 38, or the second flow channel 312 is configured as a notch provided through the first surface 37 and the second surface 38 in the thickness direction Z of the gasket 30.

Wherein the first die 10 supplies the first active slurry to the first flow path 311 when the first flow path 311 is disposed at the first surface 37. When the first flow path 311 is disposed on the second surface 38, the second die 20 supplies the first active slurry to the first flow path 311. Since the second flow path 312 penetrates the first die 10 and the second die 20, the second flow path 312 may select either one of the first die 10 and the second die 20 to be fed.

By arranging the first flow channel 311 as a groove structure and the second flow channel 312 as a notch, the simplicity of molding the first flow channel 311 and the second flow channel 312 can be improved, so that the manufacturing difficulty of the gasket 30 can be reduced.

In some embodiments of the present application, gasket 30 has a outfeed leading edge 33 disposed along its width direction Y, and the gap has a bottom wall 34 formed by the inward contraction of outfeed leading edge 33; the discharge end of the first flow passage 311 is disposed to protrude from the bottom wall 34 in the width direction Y of the gasket 30.

Wherein, the discharging front edge 33 of the gasket 30 is retracted to form two side walls 35 of the notch, the two side walls 35 are arranged at intervals along the length direction X of the gasket 30, and the bottom wall 34 of the notch is connected between the two side walls 35.

In some embodiments, the discharging end edge of the first flow channel 311 may be flush with the discharging front edge 33 of the gasket 30, or the discharging end edge of the first flow channel 311 may be retracted relative to the discharging front edge 33 of the gasket 30, which may be specifically set according to needs.

The discharge end of the first flow channel 311 is arranged to protrude from the bottom wall 34, and for example, the discharge end edge of the first flow channel 311 is arranged to be flush with the discharge front edge 33 of the gasket 30, so that the first active slurry and the second active slurry are not mixed before being output from the coating die 100; taking the example that the discharge end edge of the first flow channel 311 is retracted relative to the discharge front edge 33 of the gasket 30, the first active slurry and the second active slurry may diffuse in the area defined by the discharge end edge of the first flow channel 311 and the discharge front edge 33 of the gasket 30 before the first active slurry is output from the coating die 100, and the length of the area is shorter than the interval between the bottom wall 34 of the notch and the discharge front edge 33, so that the probability of mixing after the first active slurry and the second active slurry diffuse in the area is also reduced.

In summary, the discharge end of the first flow channel 311 protrudes from the bottom wall 34, so that the possibility of mixing the first active slurry and the second active slurry before exiting the coating die 100 can be reduced, thereby improving the coating accuracy.

In some embodiments of the present application, the discharge end of the first flow channel 311 has a discharge end edge formed by the inward shrinkage of the discharge front edge 33, and the discharge front edge 33 and the discharge end edge of the first flow channel 311 define the slurry diffusion zone 32.

In the actual coating process, the first active slurry flowing out of the first flow channel 311 and the second active slurry flowing out of the second flow channel 312 may be diffused and fused in the diffusion region and then output out of the coating die 100. In this way, after coating is completed, the first active slurry layer 400 formed by curing the first active slurry on the pole piece substrate 300 and the second active slurry layer 500 formed by curing the second active slurry have no coating gap, so that the coating effect of the battery pole piece can be effectively improved.

In some embodiments of the present application, the gasket 30 further has a third flow channel 313, the third flow channel 313 for outputting a third slurry; the third flow channels 313 are disposed on at least one side of each flow channel group 31 along the length direction X of the gasket 30.

For example, the third flow passages 313 may be provided on either side of each of the flow passage groups 31 along the length direction X of the gasket 30, or the third flow passages 313 may be provided on either side of each of the flow passage groups 31 along the length direction X of the gasket 30, and may be provided as needed.

The third flow channel 313 may be formed by a groove structure provided on the first surface 37 or the second surface 38, a through groove structure penetrating the first surface 37 and the second surface 38 in the thickness direction Z of the gasket 30, a hollow flow channel structure provided inside the gasket 30, or the like.

Specifically, the width of the second flow channel 312 > the width of the first flow channel 311 > the width of the third flow channel 313, or the width of the first flow channel 311 > the width of the second flow channel 312 > the width of the third flow channel 313 may be set, and specifically, the widths of the first flow channel 311, the second flow channel 312, and the third flow channel 313 may be set according to different coating requirements.

The third slurry may be an active slurry, and may be the same as or different from any of the first active slurry and the second active slurry. Alternatively, the third paste may be an insulating paste, such as a ceramic paste. The specific type of the third slurry may be set as desired.

By providing the third flow channel 313, the coating die 100 can simultaneously coat various kinds of slurries to meet diversified coating requirements and has high coating efficiency.

In some embodiments of the present application, each side of each flow channel group 31 is provided with a third flow channel 313, and each flow channel group 31 and the third flow channels 313 arranged on both sides and adjacent to the flow channel group 31 are configured to form a composite flow channel group; along the length direction X of the gasket 30, each end of the composite runner set includes a third runner 313 and a first runner 311 from outside to inside.

The outward-inward direction refers to a direction in which the outer edge of the gasket 30 in the longitudinal direction X thereof points toward the center of the gasket 30 along the longitudinal direction X of the gasket 30.

Referring to fig. 5 again, and referring to fig. 9, for example, the gasket 30 has a composite flow channel set, and the composite flow channel sets are sequentially arranged along the length direction X of the gasket 30: the third flow channel 313, the first flow channel 311, the second flow channel 312, the first flow channel 311 and the third flow channel 313 are exemplified, and the slurry layers formed after the single coating and curing of the coating structure are sequentially a first third slurry layer 600a, a first active slurry layer 400a, a first second active slurry layer 500a, a second first active slurry layer 400b and a second third slurry layer 600b. In this way, a structurally symmetrical pole piece can be coated on pole piece substrate 300.

As shown in fig. 9, fig. 9 is a schematic view of the structure of coating die 100 coated on a pole piece substrate 300. For example, the gasket 30 has two sets of composite flow channel groups sequentially arranged along the length direction X of the gasket 30, and each set of composite flow channel groups sequentially arranged along the length direction X of the gasket 30 is: the third flow channel 313, the first flow channel 311, the second flow channel 312, the first flow channel 311 and the third flow channel 313 are exemplified, and the slurry layers formed after the single coating and curing of the coating structure are sequentially a first third slurry layer 600a, a first active slurry layer 400a, a first second active slurry layer 500a, a second first active slurry layer 400b, a second active slurry layer 500, a third first active slurry layer 400c and a second third slurry layer 600b.

In such an embodiment, the second first active slurry layer 400b is cut into the second first active slurry layer 400b and the pole piece substrate 300 along the longitudinal direction of the pole piece substrate 300, then half of the second first active slurry layer 400b disposed adjacent to the first second active slurry layer 500a will form a pole piece with the first second active slurry layer 500a, the first active slurry layer 400a, the first third slurry layer 600a and the pole piece substrate 300 carrying it, and the other half of the second first active slurry layer 400b disposed adjacent to the second active slurry layer 500 will form a pole piece with the second active slurry layer 500, the third first active slurry layer 400c, the second third slurry layer 600b and the pole piece substrate 300 carrying it. It follows that this form of shim 30, after coating is complete, can achieve a one-die four-out.

Therefore, by arranging the third flow channel 313 and the first flow channel 311 at each end of the composite flow channel group from outside to inside, one-die-out can be realized, and the pole pieces with symmetrical structures can be formed by coating.

Referring to fig. 5 again, in some embodiments of the present application, in the same flow channel group 31, at least two first flow channels 311 are provided, all the first flow channels 311 are sequentially arranged at intervals along the length direction X of the gasket 30, and at least one second flow channel 312 is provided between two adjacent first flow channels 311.

Preferably, a second flow channel 312 is provided between each adjacent two of the first flow channels 311.

For example, the gasket 30 has a set of flow channel groups 31, and the flow channel groups 31 are sequentially arranged along the length direction X of the gasket 30: the first flow channel 311, the second flow channel 312 and the first flow channel 311 are exemplified, and slurry layers formed after single coating and curing of the coating structure are sequentially a first active slurry layer 400a, a first second active slurry layer 500a and a second first active slurry layer 400b. In this way, pole pieces of symmetrical structure can also be coated on pole piece substrate 300.

For another example, the gasket 30 has two flow channel groups 31 sequentially arranged along the length direction X of the gasket 30, and each flow channel group 31 is sequentially arranged along the length direction X of the gasket 30: the slurry layers formed by single coating and curing of the coating structure are, for example, a first flow channel 311, a second flow channel 312 and a first flow channel 311, and the slurry layers formed by single coating and curing of the coating structure are a first third slurry layer 600a, a first active slurry layer 400a, a first second active slurry layer 500a, a second first active slurry layer 400b, a second active slurry layer 500, a third first active slurry layer 400c and a second third slurry layer 600b in sequence. In this embodiment, one die four out can be achieved after coating is completed.

Therefore, at least two adjacent first channels 311 are provided with a second channel 312, which also realizes one-die extrusion, and can be coated to form a pole piece with a symmetrical structure.

Referring to fig. 2, 3 and 4, and also referring to fig. 5, 6 and 7, the application further provides a coating die 100, where the coating die 100 includes a first die 10, a second die 20 and a gasket 30, the gasket 30 is sandwiched between the first die 10 and the second die 20 and cooperates with the first die 10 and the second die 20 to form first discharge holes corresponding to the first flow channels 311 one by one and second discharge holes corresponding to the second flow channels 312 one by one, and the width of each first discharge hole is smaller than the width of each second discharge hole.

Alternatively, the first die 10 and the second die 20 may have a square body structure or a columnar body structure, which is not limited in the embodiment of the present application. The first die 10 and the second die 20 may be made of metal materials such as cast iron, aluminum, etc., or nonmetal materials such as plastic, polyester fiber, etc., which are not limited in this embodiment.

Wherein, the number of the first discharging holes is equal to and corresponds to the number of the first flow channels 311, and the number of the second discharging holes is equal to and corresponds to the number of the second flow channels 312. The width of the first flow channel 311 is equal to the width of the first discharge port, and the width of the second flow channel 312 is equal to the width of the second discharge port.

The width of each first discharge hole is smaller than that of each second discharge hole, so that the first active slurry layer 400 and the second active slurry layer 500 with different widths can be formed by coating, and the requirements of pole piece coating are met.

In some embodiments of the present application, a first cavity 12 and a first feeding port 11 are disposed on the first die 10, and the first cavity 12 is communicated between the first feeding port 11 and the first flow channel 311; and/or the second die 20 is provided with a second cavity 22 and a second feeding port 21, and the second cavity 22 is communicated between the second feeding port 21 and the second flow channel 312.

The first cavity 12, the first feed port 11, the second cavity 22, and the second feed port 21 may all be disposed on the first die 10 or the second die 20, or the first cavity 12 and the first feed port 11 may be disposed on the first die 10, and the second cavity 22 and the second feed port 21 may be disposed on the second die 20. The following embodiments will be described taking the example that the first cavity 12 and the first feed port 11 are disposed on the first die 10, and the second cavity 22 and the second feed port 21 are disposed on the second die 20. In such an embodiment, the first die 10 and the second die 20 are identical, and the first die 10 and the second die 20 may be common, thus reducing difficulty in die fabrication. The following examples will each be described by taking the first die 10 as the upper die and the second die 20 as the lower die.

The first cavity 12 may store the first active slurry, and the first feed port 11 allows the first active slurry of the first active slurry source to enter the first cavity 12 and be stored. The second chamber 22 may store a second active slurry, and the second feed port 21 allows the second active slurry of the second active slurry source to enter the second chamber 22 and be stored.

Through setting up first cavity 12, first feed inlet 11, second cavity 22 and second feed inlet 21 for first active slurry source can be through first feed inlet 11 continuous feed to first cavity 12 in, and the second active slurry source can be continuous feed to second cavity 22 in, and then, coating die 100 can export first active slurry and second active slurry in succession, thereby helps realizing continuous coating's purpose.

In some embodiments of the present application, a gasket 30 is interposed between the first die 10 and the second die 20 and cooperates with the first die 10 and the second die 20 to form each third discharge port in one-to-one correspondence with each third flow channel 313. The first die 10 or the second die 20 is provided with feed channels 13 in one-to-one correspondence with the third flow channels 313, and each feed channel 13 is communicated between a third slurry source and the corresponding third flow channel 313 and is used for inputting the third slurry into the corresponding third flow channel 313.

The following examples are given by taking the first die 10 provided with the feed passage 13 as an example.

Wherein, first discharge gate, second discharge gate and third discharge gate all locate the ejection of compact side of coating die 100, and at the in-process of coating, first discharge gate is used for exporting first active thick liquids, and the second discharge gate is used for exporting second active thick liquids, and the third discharge gate is used for exporting third thick liquids.

Referring to fig. 10, and simultaneously referring to fig. 5, fig. 10 is a schematic structural diagram of a pole piece manufacturing apparatus 1000 in the present application. In some embodiments of the present application, the present application also provides a pole piece manufacturing device 1000, the pole piece manufacturing device 1000 comprising a coating die 100, the coating die 100 for coating a pole piece substrate 300.

The pole piece manufacturing device 1000 further comprises a slurry conveying device and a pole piece substrate conveying device. The slurry delivery device is configured to deliver the first active slurry and the second active slurry into the coating die 100. For example, the slurry delivery device may include a first active slurry source, a first delivery pump for delivering the first active slurry from the first active slurry source into the first chamber 12 through the first feed port 11, and a second delivery pump for delivering the second active slurry from the second active slurry source into the second chamber 22 through the second feed port 21. The pole piece substrate conveying device comprises a pole piece substrate release roller 700, a pole piece substrate winding roller 800 and a pole piece substrate coating roller 200 arranged between the pole piece substrate release roller 700 and the pole piece substrate winding roller 800 along the conveying direction of the pole piece substrate 300. The pole piece substrate release roller 700 is used for releasing the wound pole piece substrate 300, the pole piece substrate wind-up roller 800 is used for winding the pole piece substrate 300 after the sizing agent is solidified, and the pole piece substrate coating roller 200 stretches and supports the pole piece substrate 300 in the process of moving the pole piece substrate 300, so that the coating die head 100 can coat the pole piece substrate 300.

In the present application, according to different kinds of battery cells, different kinds of gaskets 30 may be designed, and the width ratio of the first flow channel 311 to the second flow channel 312 on the different kinds of gaskets 30 is different. Thus, when the coating width ratio of the first active paste and the second active paste on the pole piece substrate 300 is changed, the different kinds of gaskets 30 can be replaced and coated by being clamped between the first die head 10 and the second die head 20, so as to meet the requirements of pole piece manufacturing.

In some embodiments of the present application, in the same flow channel group 31, at least two first flow channels 311 are provided, all the first flow channels 311 are sequentially arranged at intervals along the length direction X of the gasket 30, one second flow channel 312 is disposed between every two adjacent first flow channels 311, the gasket 30 further has a third flow channel 313, two opposite sides of each flow channel group 31 disposed along the length direction X of the gasket 30 are provided with third flow channels 313, and the third flow channels 313 are used for outputting third slurry.

The slurry conveying device further comprises a third slurry source and a third conveying pump, wherein the third conveying pump is used for conveying the third slurry in the third slurry source into the third flow channel 313 through the feeding channel 13.

Specifically, the third slurry may be an active slurry, which may be the same as any one of the first active slurry and the second active slurry, or may be different from both the first active slurry and the second active slurry. Alternatively, the third paste may be an insulating paste, such as a ceramic paste. The specific type of the third slurry may be set as desired.

Wherein each flow channel group 31 and the third flow channel 313 group 31 arranged at both sides and adjacent to the flow channel group are configured to form a composite flow channel group.

For example, the gasket 30 has a plurality of composite flow channel groups, and the composite flow channel groups are sequentially arranged along the length direction X of the gasket 30: for example, the third flow channel 313, the first flow channel 311, the second flow channel 312, the first flow channel 311 and the third flow channel 313 are used as examples, and the coating structure can be coated on the pole piece substrate 300 to form a pole piece with symmetrical structure after single coating and solidification.

As shown in fig. 9, for example, the gasket 30 has two sets of composite flow channels sequentially arranged along the length direction X of the gasket 30, and each set of composite flow channels sequentially arranged along the length direction X of the gasket 30 is: the third flow channel 313, the first flow channel 311, the second flow channel 312, the first flow channel 311, and the third flow channel 313 are exemplified, and the gasket 30 of this type can realize one-die four-out after coating is completed.

It can be seen that one-die-out can be achieved by providing one second flow channel 312 between each adjacent two first flow channels 311, and providing third flow channels 313 on opposite sides of each flow channel group 31 along the length direction X of the gasket 30.

In some embodiments of the present application, the swelling ratio of the first active paste is greater than the swelling ratio of the second active paste, and the third paste is an insulating paste.

The insulating paste is coated to form an insulating paste layer. The width of the second active slurry layer 500 formed by curing the second active slurry in the same pole piece is the largest, and the width of the second active slurry layer 500 can be in the range of 60mm to 80mm, and the second active slurry layer 500 is the main active slurry layer on the pole piece. The width of the first active slurry layer 400 formed by curing the first active slurry is smaller, and may be in the range of 1mm to 2mm, and the first active slurry layer 400 is mainly located at the edge of the pole piece. The third paste is an insulating paste, and the main purpose of the arrangement is to realize edge insulation of the pole pieces so as to reduce the risk of edge short circuit between two pole pieces with opposite polarities, which are adjacently arranged in the electrode assembly.

In the conventional pole piece manufacturing process, in order to prevent the edge of the pole piece from being raised, the pole piece substrate 300 is generally coated after the area on the pole piece substrate 300 where the edge of the pole piece is formed is thinned. However, after the electrode assembly is formed by winding the electrode sheet manufactured in this manner, gaps are easily formed inside the electrode assembly due to the presence of the thinned region, and lithium is easily separated, resulting in a decrease in the energy density of the battery cell.

By setting the swelling ratio of the first active slurry to be greater than that of the second active slurry, the first active slurry is coated on the thinned area of the pole piece substrate 300, and the second active slurry is coated on the non-thinned area of the pole piece substrate 300, so that the first active slurry layer 400 formed by curing the first active slurry and the second active slurry layer 500 formed by curing the second active slurry are expanded after contacting with the electrolyte in the battery cell, and the size of the first active slurry layer 400 expanded in the thickness direction of the pole piece substrate 300 is greater than the size of the second active slurry layer 500 expanded in the thickness direction of the pole piece substrate 300. As such, the expanded volume of the first active slurry layer 400 may effectively fill the gap to enable normal lithium deintercalation.

In some embodiments of the present application, the thickness of the region of the pole piece substrate 300 corresponding to the first flow channel 311 is smaller than that of other regions along the thickness direction of the pole piece manufacturing device 1000.

That is, the region of the pole piece substrate 300 to which the first active slurry is applied needs to be thinned. Therefore, the risk of edge bulging of the pole piece in the battery cell in the charging and discharging process can be reduced.

Referring to fig. 1 to 10 together, according to some embodiments of the present application, a gasket 30 is provided for pole piece coating, at least one flow channel group 31 is disposed on the gasket 30, the flow channel group 31 includes a first flow channel 311 and a second flow channel 312, the first flow channel 311 and the second flow channel 312 are sequentially arranged along a length direction X of the gasket 30, the first flow channel 311 is used for outputting a first active slurry, and the second flow channel 312 is used for outputting a second active slurry.

Since the first flow channel 311 for outputting the first active slurry and the second flow channel 312 for outputting the second active slurry are both located on the gasket 30, different kinds of gaskets 30 can be designed according to different kinds of battery cells, and the width ratio of the first flow channel 311 to the second flow channel 312 on the different kinds of gaskets 30 is different. In this way, according to the requirements of pole piece manufacturing, the gasket 30 with the width ratio of the first runner 311 and the second runner 312 is selected to be clamped between the first die head 10 and the second die head 20, i.e. the first active slurry and the second active slurry with the width ratio being adapted can be output, and then the first active slurry layer 400 and the second active slurry layer 500 with the width ratio being adapted can be formed by curing, so as to meet the requirements of pole piece manufacturing.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples only represent a few embodiments of the present application, which are described in more detail and are not to be construed as limiting the scope of the claims. It should be noted that it would be apparent to those skilled in the art that various modifications and improvements could be made without departing from the spirit of the present application, which would be within the scope of the present application. Accordingly, the scope of protection of the present application is to be determined by the claims appended hereto.

Claims (18)

1. The utility model provides a gasket for pole piece coating, its characterized in that is provided with at least a set of runner group (31) on the gasket, runner group (31) are including first runner (311) and second runner (312), first runner (311) with second runner (312) are followed length direction (X) of gasket is laid in proper order, first runner (311) are used for exporting first active slurry, second runner (312) are used for exporting second active slurry.

2. Gasket according to claim 1, characterized in that the gasket has a first surface (37) and a second surface (38) arranged opposite each other in the thickness direction (Z) thereof, the first flow channel (311) being provided at the first surface (37) or the second surface (38).

3. Gasket according to claim 2, characterized in that the first flow channel (311) is configured as a groove structure concavely formed by the first surface (37) or the second surface (38).

4. A gasket according to claim 3, characterized in that the first flow channel (311) has a groove depth H ₁ The thickness of the gasket is H ₂ ，H ₁ The conditions are satisfied: 60% H ₂ ≤H ₁ ≤80％H ₂ 。

5. The gasket of claim 4 wherein H ₁ The conditions are satisfied: 65% H ₂ ≤H ₁ ≤75％H ₂ 。

6. Gasket according to claim 1, characterized in that the discharge end of the first flow channel (311) is arranged to protrude beyond the discharge end of the second flow channel (312) in the width direction (Y) of the gasket.

7. A gasket according to claim 1, characterized in that the gasket has a first surface (37) and a second surface (38) arranged opposite in the thickness direction (Z) thereof;

the second flow channel (312) is configured as a groove structure formed by recessing the first surface (37) or the second surface (38), or the second flow channel (312) is configured as a notch provided through the first surface (37) and the second surface (38) in the thickness direction (Z) of the gasket.

8. Gasket according to claim 7, characterized in that it has a outfeed front edge (33) arranged in its width direction (Y), the gap having a bottom wall (34) formed by the inward shrinkage of the outfeed front edge (33); along the width direction (Y) of the gasket, the discharge end of the first flow channel (311) is arranged to protrude from the bottom wall (34).

9. The gasket according to claim 8, characterized in that the discharge end of the first flow channel (311) has a discharge end edge formed by the inward collapsing of the discharge front edge (33), the discharge front edge (33) and the discharge end edge of the first flow channel (311) defining a slurry diffusion zone (32).

10. The gasket according to claim 1, characterized in that the gasket further has a third flow channel (313), the third flow channel (313) being for outputting a third slurry; the third flow channels (313) are arranged on at least one side of each flow channel group (31) along the length direction (X) of the gasket.

11. Gasket according to claim 10, wherein each side of each of said sets of flow channels (31) is provided with a third flow channel (313), each set of flow channels (31) and said sets of third flow channels (313) arranged on both sides and adjacent thereto (31) being configured to form a composite set of flow channels;

Along the length direction (X) of the gasket, each end of the composite flow passage group comprises one third flow passage (313) and one first flow passage (311) from outside to inside.

12. Gasket according to any one of claims 1 to 11, characterized in that in the same flow channel group (31) at least two first flow channels (311) are provided, all first flow channels (311) being arranged at intervals in sequence along the length direction (X) of the gasket, at least one second flow channel (312) being provided between two adjacent first flow channels (311).

13. A coating die, comprising:

a first die head (10);

a second die (20); and

the gasket of any one of claims 1 to 12, wherein the gasket is sandwiched between the first die head (10) and the second die head (20) and cooperates with the first die head (10) and the second die head (20) to form first discharge ports corresponding to the first flow channels (311) one by one and second discharge ports corresponding to the second flow channels (312) one by one, and the width of each first discharge port is smaller than the width of each second discharge port.

14. The coating die according to claim 13, wherein a first cavity (12) and a first feed port (11) are provided on the first die (10), and the first cavity (12) is communicated between the first feed port (11) and the first flow channel (311); and/or

The second die head (20) is provided with a second cavity (22) and a second feeding port (21), and the second cavity (22) is communicated between the second feeding port (21) and the second flow channel (312).

15. A pole piece manufacturing apparatus comprising a coating die as claimed in any one of claims 13 to 14 for coating a pole piece substrate.

16. The pole piece manufacturing device according to claim 15, wherein in the same runner group (31), at least two first runners (311) are arranged at intervals in sequence along the length direction (X) of the gasket, one second runner (312) is arranged between every two adjacent first runners (311), the gasket further comprises third runners (313), and the third runners (313) are arranged on two opposite sides of each runner group (31) arranged along the length direction (X) of the gasket, wherein the third runners (313) are used for outputting third slurry.

17. The pole piece manufacturing device of claim 16, wherein the first active slurry has a swelling rate greater than a swelling rate of the second active slurry, and the third slurry is an insulating slurry.

18. The pole piece manufacturing apparatus according to claim 15, wherein a thickness of a pole piece base material region corresponding to the first flow passage (311) is smaller than that of other regions in a thickness direction of the pole piece.

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