| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery with high durability, capable of exhibiting excellent battery performance (for example, high energy density and high input/output density) over a long period of time.SOLUTION: There is provided a nonaqueous electrolyte secondary battery comprising: a positive electrode; a negative electrode 20; and a nonaqueous electrolyte. The negative electrode 20 comprises a negative electrode collector 22 and a negative electrode active material layer 24 formed on the collector. The negative electrode active material layer 24 includes: (i) a main negative electrode active material layer 242 formed on the surface of the negative electrode collector 22 and mainly composed of a carbon material; and (ii) an LTO layer 244 formed on the main negative electrode active material layer 242 and including a lithium titanium composite oxide and other negative electrode active material that is the same kind with or different from a negative electrode active material in the main negative electrode active material layer 242. The content X of the lithium titanium composite oxide contained in the LTO layer 244 and the content Y of the negative electrode active material satisfy an expression: 40<Y/(X+Y)×100<90. |
