Binding agent for lithium ion battery and lithium ion battery using binding agent

Abstract

The invention belongs to the technical field of lithium ion batteries, and particularly relates to a binding agent for a lithium ion battery and the lithium ion battery using the binding agent. The binding agent comprises a polymer containing a lithium salt branch; being as a conductive binding agent, besides relatively good binding strength, the binding agent has the outstanding characteristics that the conductivity is high; due to -COOLi contained in the branch, lithium ions can be separated out, the binding agent becomes a conductive polymer under the effect of an electric field, and the transmission of the ions can be accelerated, so that on the one hand, the ionic conductivity is improved, and on the other hand, the battery capacity under high-current charging and discharging conditions and the rate capability of the battery charging-discharging cycle are improved; and furthermore, relatively low viscosity can be kept at low temperature, and the binding resistance of the binding agent is accordingly reduced, so that the rapid conduction of Li<+> in the binding agent can be facilitated, and further the effect of improving the low-temperature performance can be achieved.

Description

technical field [0001] The invention belongs to the technical field of lithium ion batteries, and particularly relates to a binder for lithium ion batteries and a lithium ion battery using the same. Background technique [0002] Lithium-ion battery is one of the most widely studied and in-depth energy storage devices. Because of its high capacity density, high cycle life, green environmental protection, wide operating temperature range and high safety performance, it is widely used in smart phones, Tablet PCs, electric vehicles and other fields. The performance of the electrode sheet of the lithium-ion battery is one of the key factors that determine the performance of the lithium-ion battery, which is mainly composed of electrode active materials, conductive agents, binders and current collectors (copper foil or aluminum foil, etc.); It is used to bind electrode active material and conductive agent particles, and at the same time bind them to the surface of metal current c...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to provide a binder for lithium-ion batteries to improve the cycle performance, rate performance and low-temperature performance of lithium-ion batteries in view of the shortcomings of existing binders with poor conductivity and stability

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