| abstract |
A lithium secondary battery capable of increasing the capacity is provided. A positive electrode 3; a negative electrode 4 having a metal material such as Si, Sn, Al, Si alloy, Sn alloy, and Al alloy that can be alloyed with lithium; an acid, an alkali that dissolves an oxide of the metal material; The case 2 was sealed by immersing the negative electrode 4 made of an electrolyte containing an additive made of fluoride and the like, which was oxidized in a certain amount in the negative electrode oxidation step, together with the positive electrode 3 in the electrolyte. [Selection] Figure 3 |