Extruding coating type die head gasket capable of eliminating coating edge effect

Abstract

The invention discloses an extruding coating type die head gasket capable of eliminating the coating edge effect and belongs to the technical field of lithium battery coating. The extruding coating type die head gasket comprises a die head gasket body, wherein a discharging hole is formed in the die head gasket body; the die head gasket body comprises a lower gasket and upper extending gaskets fixedly arranged at the left and right upper ends of the lower gasket; the space between the inner wall of the lower gasket and the two upper extending gaskets forms the discharging hole; and chamferingstructures for improving the fluid pressure when slurry flows to the edges of the upper extending gaskets via the discharging hole are arranged at mutually closed ends of the two upper extending gaskets, so that when the slurry is coated, the fluid pressure at the die head lip edge is stable, the speed of slurry extruded out of a slit is distributed uniformly, the edge thickness consistency of thecoated film surface is high, the coated edge film thickness and the range of the film edge abnormal area can be more effectively controlled to realize continuous coating of multiple films.

Description

technical field [0001] The invention relates to the technical field of lithium battery coating, in particular to an extrusion coating type die gasket capable of eliminating the coating edge effect. Background technique [0002] With the rapid development of new energy vehicles in recent years, the requirements for the safety, consistency, and energy density of lithium-ion power batteries are getting higher and higher. If you want to improve the safety of batteries, the consistency of batteries , Improving the energy density of the battery cell is very important for how to ensure the stability of the coating surface density and the consistency of the thickness during the manufacturing process of the battery cell. How to ensure the consistency of the surface density of the coating and the stability of the coating thickness directly affect the consistency of the battery cell and the safety of the battery system. [0003] As a high-precision, intelligent, and stable production ...

AI Technical Summary

Problems solved by technology

[0004] The electrode slurry is at the outlet of the lip of the coating die, and the edge of the die gasket is often where the fluid pressure is the highest. The electrode slurry is coated on the current collector, which is prone to bulging; if the positive electrode bulging is serious, it will easily cause roll Cracking on the edge of the pole piece during the pressing process, severe wavy edges on the pole piece edge after slitting, severe bulging of the negative electrode, excessive compaction density on the pole piece edge after rolling, and electrode cell edge cracking after cycling. Lithium, a safety hazard

[0005] Although the prior art has proposed a method of improving the flow of slurry inside the extrusion die by setting chamfers on the outer edge of the discharge port of the die gasket, this method can eliminate the dead zone of the slurry to a certain extent, Improve the coating effect on the edge of the discharge port so as to avoid the bulging phenomenon of the pole piece, but this type of gasket cannot effectively reduce the thickness of the coated edge material area in the actual application process, and the industrial coating process can reduce the thickness of the thinned area. Both thickness and width have certain requirements, and the thinning area cannot be effectively controlled

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