Patent attributes
A secondary battery having a feature in which a positive electrode, a negative electrode and electrolyte are provided; the negative electrode includes a negative electrode active material layer which is alloying at least at a portion of a boundary face with a negative electrode current collector; an approximately tabular electrode body structure is formed by a constitution in which a laminated body of the lamellar positive electrode and the lamellar negative electrode is wound or folded; and in the approximately tabular electrode body structure, relation of B≦1.5A is satisfied when length in a perpendicular direction with respect to a bended portion of the laminated body is made to be A and length in a parallel direction with respect to the bended portion of the laminated body is made to be B.