Nonaqueous electrolytic secondary battery

A nonaqueous electrolytic secondary battery of excellent characteristics is provided. The nonaqueous electrolytic secondary battery includes: a positive electrode case; a negative electrode case fixed to the positive electrode case, and that forms a storage space with the positive electrode case in between the negative electrode case and the positive electrode case; a positive electrode portion provided on the positive electrode case in the storage space, and that contains a lithium compound as positive electrode active material; a negative electrode portion provided on the negative electrode case in the storage space, and that contains SiO x (0 ¤ x < 2) as negative electrode active material; and a nonaqueous electrolyte stored inside the storage space. The negative electrode case includes a base layer, and a nickel layer disposed opposite the storage space with respect to the base layer, and that has a higher thermal conductivity than the base layer, and a thickness of 2.6 µm or more.