Electrode pole piece and electrochemical device

Abstract

The invention relates to the field of batteries, in particular to an electrode pole piece and an electrochemical device. The electrode pole piece comprises a current collector and an electrode activematerial layer arranged on at least one surface of the current collector, wherein the current collector comprises a supporting layer and a conductive layer arranged on at least one surface of the supporting layer, the thickness D2 of a single surface of the conductive layer is greater than or equal to 30nm and less than or equal to 3mu m, the supporting layer is made of a high polymer material ora high polymer composite material, and the thickness D1 of the supporting layer is greater than or equal to 1mu m and less than or equal to 20mu m; wherein the electrode active material layer comprises an electrode active material, a binder and a conductive agent, the total thickness D < total > of the electrode active material layer satisfies 200 > = D < total > / D1 > = 1, and the binder content in the electrode active material layer is not less than 1 wt% based on the total weight of the electrode active material layer. The electrode pole piece has good machinability, and the electrochemicaldevice comprising the electrode pole piece has high energy density and good electrical performance and safety.

Description

Technical field [0001] This application relates to the field of batteries, in particular to an electrode pole piece and an electrochemical device. Background technique [0002] Lithium-ion batteries are widely used in electric vehicles and consumer electronic products due to their advantages of high energy density, high output power, long cycle life and low environmental pollution. With the continuous expansion of the application range of lithium ion batteries, the requirements for the weight energy density and volume energy density of lithium ion batteries are getting higher and higher. [0003] In order to obtain lithium-ion batteries with higher mass energy density and volumetric energy density, the following improvements are usually made to lithium-ion batteries: (1) Choose a positive electrode material or negative electrode material with a high specific discharge capacity; (2) Optimize the mechanical design of lithium-ion batteries , To minimize its volume; (3) Choose a posit...

AI Technical Summary

Problems solved by technology

[0005] For pole pieces and batteries using metal-coated plastic current collectors, although the energy density is improved, it may cause some performance degradation in terms of processability and electrochemical performance.

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