Patent ID: 8440349

Claim:
A nonaqueous electrolytic solution for a lithium secondary battery, comprising an electrolyte salt that is dissolved in a nonaqueous solvent, comprising: fluoroethylene carbonate, which is an ethylene carbonate derivative, and 0.05 to 5% by weight of (A) at least one alkyne derivative represented by the general formulas (II) to (VII): wherein R 4 to R 10 each independently represents a hydrogen atom, a C 1 to C 12 alkyl group, a C 3 to C 6 cycloalkyl group or a C 6 to C 12 aryl group; and, R 5 and R 6 , and R 7 and R 8 may be taken in combination to each other to represent a C 3 to C 6 cycloalkyl group, Y 1 and Y 2 may be the same or different and each represent —COOR 10 , —COR 10 or SO 2 R 10 , and x represents an integer of 1 or 2, wherein R 11 to R 13 each independently represents a hydrogen atom, a C 1 to C 12 alkyl group, a C 3 to C 6 cycloalkyl group, a C 6 to C 12 aryl group or a C 7 to C 12 aralkyl group, or R 12 and R 13 may be taken in combination to represent a C 3 to C 6 cycloalkyl group, W represents a sulfoxide group, a sulfone group or an oxalyl group, Y 3 represents a C 1 to C 12 alkyl, alkenyl or alkynyl group, a C 3 to C 6 cycloalkyl group, a C 6 to C 12 aryl group or a C 7 to C 12 aralkyl group, and x has the same meaning as above, wherein R 4 has the same meaning as above, R 14 represents a C 1 to C 12 alkyl group, a C 3 to C 6 cycloalkyl group or a C 6 to C 12 aryl group, and p represents an integer of 1 or 2 wherein the mixing ratio of the ethylene carbonate derivative to the alkyne derivative is 96:4 to 25:75.