METHOD FOR TREATING BATTERY WASTE

A method for treating battery waste includes: a first heat treatment step of heating the battery waste in an atmosphere containing at least one selected from the group consisting of nitrogen, carbon dioxide and water vapor; and after the first heat treatment step, a second heat treatment step of changing the atmosphere in the first heat treatment step and heating the battery waste in an atmosphere which is different from the atmosphere in the first heat treatment step and which contains a larger amount of oxygen than that in the first heat treatment step.