| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery of high capacity and excellent in cycle characteristics. <P>SOLUTION: The nonaqueous electrolyte secondary battery is provided with a cathode containing a cathode mixture, an anode containing an anode mixture, and a nonaqueous electrolyte containing a nonaqueous solvent as well as first and second lithium salt dissolved in it. The anode mixture contains a material capable of storing and releasing lithium ions and carbon fiber with a diameter of 1 μm or less. The material capable of storing and releasing lithium ions has an area ratio A/B of an area A at a charged state to an area B at a discharged state of 1.2, the first lithium salt is at least a kind selected from a group of LiBF<SB>4</SB>and LiB(C<SB>2</SB>O<SB>4</SB>)<SB>2</SB>, the second lithium salt is one other than the first lithium, a volume of the first lithium salt contained in the nonaqueous electrolyte is 10<SP>-4</SP>or more in a weight ratio to carbon nanofiber, and a concentration of the first lithium salt contained in the nonaqueous electrolyte is not more than 0.05 mol/dm<SP>3</SP>. <P>COPYRIGHT: (C)2007,JPO&INPIT |
