Negative electrode active material and negative electrode for sodium secondary battery using molten salt electrolyte, and sodium secondary battery using molten salt electrolyte

Abstract

An object of the present invention is to provide a negative electrode active material etc. which have a high capacity density and which can improve cycle characteristics of a sodium secondary battery using a molten salt electrolyte. The negative electrode active material for a sodium secondary battery using a molten salt electrolyte includes tricobalt tetroxide. In the negative electrode active material, the tricobalt tetroxide preferably has an average particle size d50 of 10 μm or less and a maximum particle size dmax of 30 μm or less.

Dependencies are inferred from the claim text.