Battery pole piece and preparation method and application thereof

Abstract

The invention provides a battery pole piece and a preparation method and application thereof. The battery pole piece comprises a current collector, at least two layers of pole piece membranes are laminated on at least one side surface of the current collector, the porosity of the pole piece membranes is sequentially increased along the direction far away from the surface of the current collector, and the pole piece membranes are prepared by a dry method. The active layer is provided with at least two layers of pole piece membranes, the porosity of the pole piece membranes is sequentially increased in the direction away from the surface of the current collector, the pole piece membranes with the large porosity can relieve the expansion effect of the pole piece membranes with the small porosity, the requirement for high energy density can be met, and enough lithium ion transmission channels can be provided, so that the rate capability of the pole piece is improved.

Description

technical field [0001] The invention belongs to the technical field of batteries, and relates to a battery pole piece, a preparation method and application thereof. Background technique [0002] Lithium-ion batteries, as one of the most important electrochemical energy storage devices at present, have been applied in small-capacity batteries in consumer electronics and power tools, and have gradually expanded to new energy electric vehicles, electric ships, electric aircraft, robots, etc. Emerging fields not only require lithium-ion batteries to have a larger capacity, but also continuously put forward higher requirements for their energy density. However, at present, the energy density of traditional lithium-ion battery materials has approached the theoretical value, and how to further increase the energy density has become a research hotspot. Therefore, under the premise of meeting safety and other comprehensive technical indicators, it is necessary to continuously improv...

AI Technical Summary

Problems solved by technology

Under the existing manufacturing process, the wet method is to apply the conductive paste on the current collector, the coating thickness is limited, and the multi-layer coating is difficult; if the dry method wants to achieve high energy density effect, it is necessary to The electrode layer is compacted thicker or tighter, but in the case of thicker or tighter compaction, the electrode layer will have a more serious expansion effect, affecting battery performance or even failure

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