Dry powder brick pressing preparation method of lithium ion battery pole piece

Abstract

The invention relates to a dry powder brick pressing preparation method of a lithium ion battery pole piece. The dry powder brick pressing preparation method comprises the following steps of: (1) preparing a dry mixed material, namely performing dry mixing on a negative electrode material raw material or a positive electrode material raw material, and adding a hot melt adhesive into the dry mixture to obtain the dry mixed material; (2) feeding the dry mixed material into a mold, namely adding the prepared dry mixed material into a battery pole piece mold which is internally provided with a base material sheet and is divided into an upper mold and a lower mold, placing the base material on the lower mold, and after the dry mixed material is placed on the base material, carrying out cavity closing pressing on the upper mold; and (3) conducting compaction, namely extruding the pole piece dry mixed material containing the hot melt adhesive in the die cavity, and heating the dry mixed material in the extrusion process to obtain the lithium ion battery pole piece. Compared with the prior art, the dry powder brick pressing preparation method has the advantages of being simple in process, low in investment cost, high in investment benefit, capable of greatly reducing the cost of the power battery, beneficial to electric automobiles and the like.

Description

technical field [0001] The invention relates to the field of lithium ion batteries, in particular to a method for preparing dry powder pressed bricks of lithium ion battery pole pieces. Background technique [0002] In recent years, the application range of lithium-ion batteries has become more and more extensive. Lithium batteries are widely used in energy storage power systems such as water power, fire power, wind power and solar power stations, as well as power tools, electric bicycles, electric motorcycles, electric vehicles, military equipment, Aerospace and other fields. However, the cost of lithium batteries remains high, and processing costs and raw material costs are the main factors. The manufacturing process of lithium batteries is complicated, the process route is long, the equipment investment is large and the operation is difficult. [0003] The main process of manufacturing the existing lithium-ion battery pole piece needs to go through batching system, mixe...

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Problems solved by technology

[0004] In the existing manufacturing process of lithium-ion battery pole pieces, the active material, conductive agent, adhesive, etc., and solvent are mixed and dispersed uniformly through a mixer or disperser to form a free-flowing electrode slurry, and the conductive agent is uniformly dispersed in the solvent. It is difficult to control the stability and fluidity of the electrode slurry, and there are problems such as agglomeration and sedimentation in the long-distance transportation of the slurry, and it is difficult to clean when changing batches; the slurry is coated on the substrate, and the membrane The thickness of the layer is uneven, which affects the thickness uniformity of the battery pole piece produced by the subsequent process

[0005] In addition, during the drying process, the solvent in the electrode slurry will volatilize, resulting in dry cracking of the film layer formed on the surface of the pole piece substrate; there are problems such as broken tape, stripping and sticking to the roll during the rolling process , the compaction density consistency of the film layer is poor; after slitting and die-cutting, due to the exposure of the base material of the pole piece, there are a lot of burrs on the edge of the pole piece of the ion battery

The entire manufacturing process of battery pole pieces is tedious and cumbersome, the process is complicated, the equipment is large and large, and the investment cost is very high

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