Low-temperature electrolyte and lithium ion battery containing same

Abstract

The invention discloses a low-temperature electrolyte, and relates to the technical field of lithium ion batteries, the low-temperature electrolyte comprises, by mass, 80-85% of an organic solvent, 10-15% of a lithium salt and 0.5-10% of a functional additive; the functional additive is (pyrrole-1-yloxy) methyl methanoate, and the structural formula of the functional additive is shown in the specification. The invention also provides a lithium ion battery containing the low-temperature electrolyte. Compared with the prior art, the method has the beneficial effects that the used functional additive is nitrogen-containing formate and still has relatively high ionic conductivity under the low-temperature condition of-40 DEG C, and oxygen-containing and nitrogen-containing formate can form a stable SEI film on the surface of an electrode material, so that rapid intercalation and deintercalation of lithium ions in the cycle process of the lithium ion battery are guaranteed, and the lithium ion battery has high electrochemical performance. The problem of lithium precipitation of the negative electrode under a low-temperature condition is effectively solved, and the negative electrode shows relatively excellent discharge curve and cycle performance in a low-temperature environment.

Description

technical field [0001] The present invention relates to the technical field of lithium ion batteries, in particular to a low-temperature electrolyte and a lithium ion battery containing the electrolyte. Background technique [0002] Science and technology are the primary productive forces for human development. With the advancement and development of modern science and technology, the thirst for energy is increasing day by day. As a result, problems such as the depletion of petroleum resources, the deterioration of the ecological environment and the general trend of green recycling development have led to the replacement of crude oil energy by new energy sources, which has become an exclusive topic of this century. Develop renewable resources, of which lithium-ion batteries are the primary development target, and electric vehicles will gradually replace fuel vehicles. [0003] Lithium-ion batteries mainly include positive electrode materials, separators, electrolytes and ne...

AI Technical Summary

Problems solved by technology

The publication number is a patent disclosing an ultra-low temperature electrolyte. By forming a low-impedance SEI film on the surface of the negative electrode, the electrolyte has good compatibility with the positive and negative electrode materials, and realizes the improvement of cycle performance in an ultra-low temperature environment. However, the electrolyte The additive still contains the additive vinylene carbonate, which will increase the internal resistance of the battery and hinder the further improvement of the low temperature performance of the battery

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