| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery which is superior in cycle characteristic. SOLUTION: A negative electrode 1, a separator 3, a positive electrode 2 and a separator 3 are laminated in this order and wound around a center pin 14 to form an electrode body. This electrode body is stored in a battery can 5, and insulating plates 4 are disposed at both the upper end lower faces of the electrode body. A positive electrode lead 13 is led out of a positive electrode current collector 11 and welded to a battery lid 7, and a negative electrode lead 12 is led out of a negative electrode current collector 10 and welded to the battery can 5. After an electrolyte in the battery can 5 has been filled, the battery can 5 is caulked through a sealing gasket 6. A safety valve device 8 and the battery lid 7 are therefore fixed so as to constitute a cylindrical nonaqueous electrolyte secondary battery. Polyvinylidene fluoride is used for positive electrode and negative electrode binders, and polyimide of 20% or less in the coefficient of cubic expansion is further mixed in the positive electrode binder at a composition of 5 wt.% to 90 wt.% or less, while aromatic polyamide is mixed in the negative electrode binder at the composition ratio of 1 wt.% or higher to 90 wt.% or lower. |
