NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery with high reliability that can place a current breaking mechanism in operation by raising battery internal pressure in a short time when the battery enters an overcharged state.SOLUTION: A nonaqueous electrolyte secondary battery includes an electrode body having a positive electrode plate having a positive-electrode substance layer, containing a positive electrode substance, formed on a surface of a positive electrode core body and a negative electrode plate, a nonaqueous electrolyte, and an exterior package body which houses the electrode body and nonaqueous electrolyte. A current breaking mechanism which breaks a conductive path as the pressure in the exterior package body rises is provided in at least one of a conductive path between the positive electrode plate and a positive electrode external terminal, and a conductive path between the negative electrode plate and a negative electrode external terminal. The nonaqueous electrolyte contains an overcharging suppressing agent. A specific surface area of the positive electrode active substance layer is 1.3 m/g or less, and the total surface area of the positive electrode active substance layer to the total mass of the overcharging suppressing agent in the nonaqueous electrolyte is 41 m/g or less.