AQUEOUS SOLUTION ELECTROLYTE SECONDARY BATTERY

An aqueous solution electrolyte secondary battery includes: a positive electrode including a positive electrode active material that reversibly occludes and releases lithium ions; a negative electrode including a negative electrode active material that reversibly occludes and releases lithium ions; and an aqueous solution electrolyte in which a lithium salt is dissolved. The negative electrode active material contains Mo, at least part of the Mo causes an oxidation-reduction reaction of Mo/Mo through charging and discharging, and a potential window for charging and discharging exceeds 2.0 V.