A method for reducing the wrinkling of current collectors during the preparation of electrode pole pieces

Abstract

The invention relates to a method for reducing the wrinkling of the current collector in the preparation process of the electrode pole piece. The 6-8 μm current collector is sequentially coated, rolled and die-cut to prepare the electrode pole piece. The tension adjustment and rolling of the coating process The adjustment of the passing roll angle in the process and the roll gap adjustment of the main traction roll in the die-cutting process can reduce the wrinkling of the current collector. The present invention can stably produce pole pieces on the premise of preventing the current collector from wrinkling on the current collector of 6-8 μm by regulating the process of coating, rolling and die-cutting, thereby improving the energy density and yield of the battery . The main materials of the positive and negative electrodes in the present invention are all within the limit compaction range of the material, while ensuring the processing performance of the pole piece, the utilization rate of the internal space of the battery is improved, thereby increasing the energy density of the battery. The invention reduces the weight of the battery and improves the energy density while satisfying the safety performance of the battery by introducing the lightweight design structural parts.

Description

technical field [0001] The invention belongs to the field of battery preparation technology, and in particular relates to a method for reducing the wrinkling of a current collector in the preparation process of electrode pole pieces. Background technique [0002] Lithium-ion batteries have the advantages of high specific energy, high working voltage, and long cycle life, and have been developed rapidly since their commercialization. As people have higher and higher mileage requirements for new energy vehicles, high specific energy batteries have become an industry trend. The energy density of lithium-ion batteries is closely related to the selection of positive and negative electrode active materials and the entire preparation process. The existing lithium-ion The active materials of battery cathode materials include lithium iron phosphate, lithium manganese oxide, nickel cobalt lithium manganese oxide, etc. [0003] Compared with ternary materials, lithium iron phosphate h...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to provide a method for reducing the wrinkling of the current collector during the preparation of the electrode pole piece. The method can effectively solve the problem that the thickness of the current collector in the lithium-ion battery is too large (generally 8-16 μm), resulting in low energy density. , the current collector with a small thickness is easy to wrinkle, it is difficult to produce stably, and the yield is low, which further improves the energy density of the battery, and the preparation process is simple and can be industrialized.

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