Positive electrode current collector, positive electrode sheet and electrochemical device

Abstract

The invention discloses a positive electrode collector, a positive electrode sheet and an electrochemical device. The positive electrode collector includes: a support layer having two opposite surfaces in its own thickness direction; a conductive layer arranged on two sides of the support layer. On at least one of the surfaces; wherein, the thickness D of the conductive layer 1 300nm≤D 1 ≤2μm, preferably 500nm≤D 1 ≤1.5 μm; when the tensile strain of the positive current collector is 1.5%, the increase rate T of the sheet resistance of the conductive layer is T≤30%. The positive current collector provided by the present invention can simultaneously take into account high safety performance and electrical performance, so that the positive electrode sheet and electrochemical device using it can simultaneously take into account high safety performance and electrochemical performance.

Description

technical field [0001] The invention belongs to the technical field of electrochemical devices, and in particular relates to a positive electrode current collector, a positive electrode sheet and an electrochemical device. Background technique [0002] Due to the advantages of high energy density, high output power, long cycle life and low environmental pollution, lithium-ion secondary batteries are widely used in electric vehicles and consumer electronics products. However, when the lithium-ion secondary battery is subjected to abnormal conditions such as nail penetration, it is easy to cause a short circuit in the battery. At this time, the battery generates a large current and is accompanied by a large amount of heat generated by the short circuit, which is likely to cause the battery to smoke, catch fire, or even explode. Security risks. [0003] In the prior art, separators with high puncture strength are used to avoid internal short circuits in batteries, or the hazar...

AI Technical Summary

Problems solved by technology

However, the existing technology cannot effectively control the internal short circuit and short circuit heat generation of the battery, and the safety of the battery cannot meet the increasingly high requirements of the market.

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