Electrolyte and battery

Abstract

The invention discloses an electrolyte which comprises a lithium salt, a non-aqueous organic solvent and an additive, and the additive comprises fluorophthalic anhydride. On the basis, the invention also discloses a battery comprising the electrolyte. The problem of how to improve the power and the energy density of the battery and prolong the service life of the battery can be solved.

Description

technical field [0001] This application relates to the field of electrochemistry, and more specifically, to electrolytes and batteries. Background technique [0002] For lithium batteries, there are very important technical improvement needs in terms of high power, energy density, long cycle life, safety, etc. It is generally believed that an advanced lithium battery should be a combination including a high-voltage cathode, a large-capacity anode, and a corresponding high-voltage electrolyte. However, the anodes of conventional carbonate solvent-based electrolytes begin to lose stability after exceeding 4.3 V, which makes them extremely unstable under high-voltage cathodes. [0003] For the above problems, the current solutions more or less have some defects. Specifically: (1) Use sulfone-based, fluorinated and other types of solvents to improve the pressure resistance, but these solvents have poor wettability with the battery separator due to their high viscosity, and the...

AI Technical Summary

Problems solved by technology

Specifically: (1) Use sulfone-based, fluorinated and other types of solvents to improve the pressure resistance, but these solvents have poor wettability with the battery separator due to their high viscosity, and their film-forming ability on the negative electrode is weak, which is not conducive to battery The overall improvement of performance; (2) adding an ionic liquid (such as imidazoline type or pyrrolidinyl, etc.) that can be used as a co-solvent or additive, the defect of this ionic liquid is the same as the previous solvent, and the viscosity is high; (3) using crystal Solid electrolytes such as state or amorphous, the disadvantage is that the electrolyte ionic conductivity is low, the interface resistance is large, which makes it difficult for the battery to cycle stably at a higher voltage in the ester electrolyte

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