NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery in which safety at the time of over-charging is enhanced by making various kinds of additives for securing safety at over-charging react rapidly. SOLUTION: The nonaqueous electrolyte secondary battery has a capacity ratio of a negative electrode plate to a positive electrode exceeding 1 and, in the opposed face of the positive electrode plate and the negative electrode plate, has a region where the capacity ratio of the negative electrode plate to the positive electrode plate per unit area is made smaller by 1% or more partially than the other portion is formed. The region where the capacity ratio of the negative electrode plate to the positive electrode plate per unit area is made smaller by 1% or more partially than the other portion is 5% or more and 95% or less of the whole area of the opposed portion of the positive electrode plate and the negative electrode plate. The nonaqueous electrolyte contains 1,3-dioxane and at least one kind of aromatic compound selected from a cycloalkyl benzene compound and a compound having a quaternary carbon adjoining benzene ring. COPYRIGHT: (C)2011,JPO&INPIT