Lithium secondary battery and electrolyte solution for lithium secondary battery

Abstract

The present invention provides: a lithium secondary battery which is suppressed in deterioration of a negative electrode active material due to charging and discharging and has excellent cycle characteristics, while having a long service life especially for use in a high-temperature environment; and an electrolyte solution which is used in this lithium secondary battery. A lithium secondary battery according to the present invention contains an electrolyte solution, in which a positive electrode and a negative electrode that absorb and desorb lithium during charging and discharging are immersed, and has a negative electrode that contains a silicon-based negative electrode active material. The electrolyte solution contains an unsaturated phosphoric acid ester that is represented by formula (1) (wherein each of R1-R3 independently represents a direct bond or an alkylene group having 1-5 carbon atoms).

Description

technical field [0001] The present invention relates to a high-capacity lithium secondary battery that is particularly excellent in cycle characteristics for use in a high-temperature environment and has a long life, and an electrolyte solution for the lithium secondary battery used therein. Background technique [0002] Lithium secondary batteries are widely used in portable electronic devices, personal computers, etc., and require miniaturization and light weight. On the other hand, high energy density and degradation associated with charging and discharging are required to be used in high-function electronic devices and electric vehicles. It is suppressed and has excellent cycle characteristics and long life. A lithium battery has a structure in which a positive electrode active material layer containing a positive electrode active material and a negative electrode active material layer containing a negative electrode active material respectively formed on a current colle...

AI Technical Summary

Problems solved by technology

However, it is difficult to form a stable coating with a uniform thickness that can sufficiently suppress degradation of cycle characteristics associated with use on a silicon-based negative electrode active material.

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