Ester compound, and non-aqueous electrolyte solution and lithium secondary battery each using the ester compound
View Patent ↗The present invention includes (1) an ester compound having a specific structure, (2) a nonaqueous electrolytic solution for lithium secondary battery comprising an electrolyte dissolved in a nonaqueous solvent and containing an ester compound having a specific structure in an amount of from 0.01 to 10% by weight of the nonaqueous electrolytic solution, which is excellent in initial battery capacity and cycle property, and (3) a lithium secondary battery comprising a positive electrode, a negative electrode and a nonaqueous electrolytic solution of an electrolyte salt dissolved in a nonaqueous solvent, wherein the nonaqueous electrolytic solution contains an ester compound having a specific structure in an amount of from 0.01 to 10% by weight of the nonaqueous electrolytic solution.
1. A nonaqueous electrolytic solution for a lithium secondary battery, the solution comprising an electrolyte dissolved in a nonaqueous solvent and an ester compound represented by formula (III) in an amount of from 0.01 to 10% by weight of the nonaqueous electrolytic solution:
wherein:
R 11 , R 13 , R 14 and R 15 each independently represent a hydrogen atom or a fluorine atom;
R 12 represents a hydrogen atom, a fluorine atom, a methoxy group or an ethoxy group;
at least one of R 11 to R 15 is a fluorine atom;
L 2 represents an alkenyl group having from 2 to 6 carbon atoms, an alkynyl group having from 3 to 6 carbon atoms, or a biphenyl group.
2. The nonaqueous electrolytic solution of claim 1 , wherein L 2 is a vinyl group, an allyl group or a propargyl group.
3. The nonaqueous electrolytic solution of claim 1 , wherein at least two of R 11 , R 13 and R 15 are fluorine atoms.
4. The nonaqueous electrolytic solution of claim 1 , wherein the electrolytic solution further comprises at least two selected from the group consisting of ethylene carbonate, propylene carbonate, vinylene carbonate and fluoroethylene carbonate.
5. A lithium secondary battery, comprising a positive electrode, a negative electrode and a nonaqueous electrolytic solution of an electrolyte salt dissolved in a nonaqueous solvent, wherein the nonaqueous electrolytic solution comprises an ester compound of formula (III) in an amount of from 0.01 to 10% by weight of the nonaqueous electrolytic solution:
wherein:
R 11 , R 13 , R 14 and R 15 each independently represent a hydrogen atom or a fluorine atom;
R 12 represents a hydrogen atom, a fluorine atom, a methoxy group or an ethoxy group;
at least one of R 11 to R 15 is a fluorine atom;
L 2 represents an alkenyl group having from 2 to 6 carbon atoms, an alkynyl group having from 3 to 6 carbon atoms, or a biphenyl group.