| 摘要 |
PROBLEM TO BE SOLVED: To provide a power storage device which enables the suppression of an internal short circuit caused by an expected foreign material.SOLUTION: A power storage device 1 comprises: a positive electrode 10 having a metal foil 11, and a positive electrode active material layer 12 provided on at least one surface of the metal foil; a negative electrode 20 having a metal foil 21, a negative electrode active material layer 22 provided on at least one surface of the metal foil, and a protection layer 23 provided on the negative electrode active material layer 22; and a separator 30 disposed between the positive electrode 10 and the negative electrode 20. The protection layer 23 is harder than the positive electrode active material layer 12 in hardness. Supposing that of the thickness of the positive electrode active material layer 12 of the thickness of the negative electrode active material layer 22, a larger thickness is P, the hardness of the positive electrode active material layer 12 is x, the hardness of the protection layer 23 is y, the thickness of the protection layer 23 is T, and the thickness of the separator 30 is D, they satisfy the conditions given by: x/(x+y)×(P-D)<T, and P>D. |
