| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lithium ion secondary battery that has high capacity and superior cycle characteristics when a lithium-containing complex oxide which can be charged and discharged at a high potential is used as a positive-electrode active material and a negative-electrode active material consisting principally of silicon is combined therewith. <P>SOLUTION: The lithium ion secondary battery comprises a positive electrode, a negative electrode and a nonaqueous electrolyte composition (electrolyte liquid). The positive electrode uses the positive electrode active material represented by aLi[Li<SB POS="POST">1/3</SB>M1<SB POS="POST">2/3</SB>]O<SB POS="POST">2</SB>(1-a)LiM2O<SB POS="POST">2</SB>(where M1 is one or more kinds of metal element selected from the group of Mn, Ti, Zr, and V, M2 is one or more kinds of metal element selected from the group of Ni, Co, Mn, Al, Cr, Fe, V, Mg, and Zn, and 0<a<1 is satisfied), the negative electrode uses the negative electrode material containing silicon, and the nonaqueous electrolyte composition contains lithium salt represented by (C<SB POS="POST">n</SB>F<SB POS="POST">2n+1</SB>SO<SB POS="POST">2</SB>)(C<SB POS="POST">m</SB>F<SB POS="POST">2m+1</SB>SO<SB POS="POST">2</SB>)NLi (where m, n are each an integer of equal to or larger than 2). <P>COPYRIGHT: (C)2012,JPO&INPIT |
