| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery in which the thickness of copper foil as a negative electrode collector is thin, battery capacity is difficult to fall even if a charge/discharge cycle is repeated, and swelling of a battery is small. <P>SOLUTION: In the nonaqueous electrolyte secondary battery including a wound electrode body obtained by winding a positive electrode plate and a negative electrode plate 12A in which both surfaces of copper foil 22 are coated with a negative electrode active material layer 23 through a separator, and a nonaqueous electrolyte having electrolyte salt in a nonaqueous solvent, a negative electrode collector exposing part 24 with a collector 22 made of copper foil exposed is provided on an outer circumferential side and an inner circumferential side of an end of a winding start side of the negative electrode plate 12A. In the negative electrode collector exposing part 24, an inner circumferential side exposure part 24b is formed longer than an outer circumferential side exposure part 24a, a one-side application part 25 of the negative electrode active material layer 23 is formed on the outer circumferential side exposure side 24a, and a reinforcement layer 27 is formed on the inner circumferential side exposure part 24b over a region from a position in contact with an application end 26 of the inner electrode active material layer 23 of an inner circumferential side beyond the outer circumferential one-side application part 25. <P>COPYRIGHT: (C)2013,JPO&INPIT |
