A kind of additive for lithium-ion battery electrolyte, electrolyte and lithium-ion battery

Abstract

The present invention relates to the field of lithium-ion batteries, and discloses an additive for lithium-ion battery electrolyte, electrolyte and lithium-ion battery. The additive includes additive a, additive b and additive c; the structural formula of the additive a is as structural formula 1 As shown, the additive b is at least one of lithium difluorophosphate, lithium difluorooxalate borate and lithium bisfluorosulfonimide; the additive c is vinylene carbonate, 1,3-propanesulfonate At least one of acid lactone, fluoroethylene carbonate, vinyl vinylene carbonate, vinyl sulfite, vinyl vinyl sulfite, propylene sulfite, dimethyl sulfate, and propylene sulfate. Additives are mixed through several mixtures and applied to the electrolyte of lithium-ion batteries. The electrolyte has excellent overcharge performance, and the electrolyte has excellent flame retardancy; and the lithium-ion battery using this electrolyte has a small Internal resistance and K value, good room temperature cycle performance and high temperature storage performance.

Description

technical field [0001] The invention relates to the technical field of lithium ion batteries, in particular to an additive for the electrolyte solution of the lithium ion battery, the electrolyte solution and the lithium ion battery. Background technique [0002] Lithium-ion batteries have been widely used in portable devices, electric vehicles, energy storage and other fields. However, the most important issue restricting the further development of lithium-ion batteries is the safety of the batteries themselves. Tesla electric car batteries caught fire, Samsung mobile phones exploded, etc. Accidents constantly remind us that safety is a prerequisite for batteries. Especially in the future, lithium batteries will develop in the direction of high energy density and high power, and safety issues cannot be ignored. [0003] The current method to ensure battery safety is divided into internal and external protection mechanisms. External protection relies on electronic devices, w...

AI Technical Summary

Problems solved by technology

However, the addition of existing overcharge and flame retardant additives will increase the internal resistance and K value of the battery, thereby reducing the cycle and high and low temperature performance of the battery, which undoubtedly has a negative impact on the electrical performance of the battery, especially in When the use of flame retardant and overcharge additives increases, most of the existing technologies only consider increasing the safety of the battery, but at the expense of the electrical performance of the battery

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