Electrolyte additive, electrolyte and lithium ion battery

Abstract

The invention belongs to the technical field of lithium ion batteries, and particularly relates to an electrolyte additive, an electrolyte and a lithium ion battery. According to the invention, the film-forming additive participates in the construction and regulation of the components of the interfacial film through the preferential oxidation-reduction reaction, so that the stability and firmness of the interfacial film are effectively improved. According to the present invention, by using the spontaneous adsorption of the leveling agent on the negative electrode surface and the strong coordination ability of the leveling agent and Li < + >, especially at the tip of the protrusion, the leveling agent-Li < + > complex can push Li < + > to the adjacent region through the repulsive force so as to avoid the random nucleation of Li < + > at the position, such that the growth of the lithium dendrites is inhibited; according to the electrolyte additive, a novel additive combination is provided, through the synergistic effect of the film-forming additive and the leveling agent, a stable interfacial film is constructed through the film-forming additive, uniform lithium deposition is induced through the leveling agent, and when the film-forming additive and the leveling agent are added into an electrolyte system at the same time, the film-forming additive and the leveling agent do not interfere with each other; and good cycle performance and good safety of the lithium ion battery can be realized.