NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY

A non-aqueous electrolyte secondary battery, when using an aqueous binder as a binder for a negative electrode active material, effectively exhausts the gas generated from an electrode, and thus, even when using it for a long period of time, a decrease in battery capacity is low. The non-aqueous electrolyte secondary battery includes a positive electrode active material layer on a surface of a positive electrode current collector, a negative electrode active material layer comprising an aqueous binder on a surface of a negative electrode current collector, a separator for maintaining an electrolytic solution, and a gas releasing means for releasing a gas generated within the power generating element to an extra space inside of the outer casing, and in which the ratio value of a volume f the extra space to a volume of pores included in the power generating element is 0.5 to 1.0.