A kind of lithium ion battery electrolyte and lithium ion battery containing the electrolyte

Abstract

The invention relates to a lithium ion battery electrolyte and a lithium ion battery containing the electrolyte, belonging to the technical field of energy materials. The electrolyte contains lithium hexafluorophosphate, propylene carbonate, ethylene carbonate, diethyl carbonate and octylphenol polyoxygen vinyl ether. By reasonably controlling the content and type of octylphenol polyoxyethylene ether in the electrolyte, the resulting electrolyte has excellent lithiophilic properties, and combines with lithium ions to form a stable polyether / lithium complex, which can Regulated Li-ion uniform deposition. Meanwhile, the formed polyether / lithium complexes can also self-assemble to form templates for the construction of stable SEI films, thereby limiting the growth of lithium dendrites and prolonging the cycle life of lithium anodes. By controlling the content of octylphenol polyoxyethylene ether in the electrolyte, the viscosity of the electrolyte is reduced, and the Li + The transport during charge and discharge improves the tolerance of lithium anodes to high current densities. Lithium-ion batteries containing this electrolyte have excellent cycle performance and rate performance.

Description

technical field [0001] The invention belongs to the technical field of energy materials, in particular to a lithium-ion battery electrolyte and a lithium-ion battery containing the electrolyte. Background technique [0002] The rapid and in-depth research and development of lithium batteries with high energy density has been stimulated by the increasing demand for portable devices, electric vehicles, and large-scale grid energy storage in modern society. Li-O 2 and Li-S batteries have attracted more and more attention due to their high-capacity cathodes combined with the highest-capacity lithium metal anodes, but as Li-O 2 In-depth research on Li-S batteries and Li-S batteries have found that the huge obstacle to their commercialization is actually the problem of the metal lithium negative electrode, not its positive electrode. Among them, the main problems of metallic lithium anodes are the growth of lithium dendrites, infinite volume change, and extreme instability of so...

AI Technical Summary

Problems solved by technology

Li-O 2 and Li-S batteries have attracted more and more attention due to their high-capacity cathodes combined with the highest-capacity lithium metal anodes, but as Li-O 2 In-depth research on Li-S batteries and found that the huge obstacle to their commercialization is actually the problem of metal lithium negative electrode, not its positive electrode

Among them, the main problems of metal lithium anodes are the growth of lithium dendrites, infinite volume change and extreme instability of the solid-liquid interface (SEI).

However, due to the lack of a stable SEI film, the electrolyte is continuously consumed, so the assembled lithium battery cannot maintain a long cycle life.

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