| 摘要 |
PROBLEM TO BE SOLVED: To provide a power storage device that is able to sufficiently reduce the expansion of an active material layer.SOLUTION: A power storage device 1 comprises a positive electrode 10, a negative electrode 20, and a separator 30 arranged between the positive electrode 10 and the negative electrode 20. The negative electrode 20 has: a negative-electrode active material layer 22 provided on at least one face of a metal foil 21; and a protective layer 23 provided on the negative-electrode active material layer 22. The negative-electrode active material layer 22 includes an active material and a first binder. The protective layer 23 includes an insulating material and a second binder. If the tensile strength of the first binder is I, the tensile strength of the second binder is I, the thickness of the negative-electrode active material layer 22 is D, the thickness of the protective layer 23 is D, the volume percentage of the first binder in the negative-electrode active material layer 22 is V, and the volume percentage of the second binder in the protective layer 23 is V, I<Iand I×D×V<I×D×Vare satisfied. |
