| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electrolytic solution which can improve cycle characteristics, and a battery. <P>SOLUTION: The negative electrode 22 contains as a negative electrode active material a single substance, an alloy and a compound of a metal element or a semi-metal element capable of forming an alloy with lithium. The separator 23 is impregnated with an electrolytic solution in which an electrolyte salt is dissolved in a solvent. The electrolyte salt contains a first electrolyte salt made of LiB(C<SB>2</SB>O<SB>4</SB>)<SB>2</SB>and a second electrolyte salt made of at least one kind out of LiPF<SB>6</SB>, LiBF<SB>4</SB>, LiN(CF<SB>3</SB>SO<SB>2</SB>)<SB>2</SB>, LiN(C<SB>2</SB>F<SB>5</SB>SO<SB>2</SB>)<SB>2</SB>, LiClO<SB>4</SB>, LiAsF<SB>6</SB>, and LiC(CF<SB>3</SB>SO<SB>2</SB>)<SB>3</SB>. The solvent contains 4-fluoroethylene carbonate. A film is produced on the negative electrode 22 by the first electrolyte salt and a high ionic conductivity is obtained by the second electrolyte salt 22, and furthermore, oxidative degradation reaction of the electrolyte solution brought about at the positive electrode 21 is suppressed by 4-fluoroethylene carbonate. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
