LITHIUM SECONDARY BATTERY, ELECTROLYTE FOR LITHIUM SECONDARY BATTERY, AND ADDITIVE AGENT FOR ELECTROLYTE OF LITHIUM SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide: a lithium secondary battery superior in initial capacity and cycle characteristic; an electrolyte for a lithium secondary battery; and an additive agent for an electrolyte of a lithium secondary battery.SOLUTION: A lithium secondary battery comprises: a positive electrode 10 capable of occluding and releasing lithium ions; a negative electrode 12 capable of occluding and releasing lithium ions; and a nonaqueous electrolyte in contact with the positive electrode 10 and the negative electrode 12. The nonaqueous electrolyte includes: a lithium hexafluorophosphate; and a boroxine compound which is in a liquid state at 25°C, and is expressed by (RO)(BO), where R's independently represent an organic group having a chain alkyl group of a straight chain with three or more carbon atoms, in which the chain alkyl group may have a branch. In the case of the chain alkyl group having a branch, the number of atoms of the chain alkyl group in a part forming the straight chain is three or more.SELECTED DRAWING: Figure 1