| 摘要 |
PROBLEM TO BE SOLVED: To provide an organic solvent electrolyte having self-extinguishing capability by dissolving a lithium salt of solute in a mixed solvent containing a cyclic phosphate and a cyclic carbonate in the specified ratio. SOLUTION: As a lithium salt used as a solute, LiPF6 , or the like is listed. The concentration of the lithium salt is 0.1-1.5 mole/1. The mixed solvent contains 20-55 vol.% of cyclic phosphate represented by the formula and 10-80 vol.% of cyclic carbonate. In the formula, R<1> represents a 2-8C alkylene group, R<2> represents a 1-4C alkyl group. The cyclic phosphate has self-extinguishing capability, and its capability is increased with decrease in the number of carbon atoms and the content of hydrogen. Preferably, methyl ethylene phosphate, ethylene phosphate, and the like are listed. As the cyclic carbonate, ethylene carbonate, propylene carbonate, and the like are listed. |
