A battery includes a power generator and a covering body covering the power generator. The power generator includes a positive electrode layer, a negative electrode layer, and a solid electrolyte layer positioned between the positive electrode layer and the negative electrode layer. At least one selected from the group consisting of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer contains a halogen-containing solid electrolyte. The covering body includes a base material layer, a resin layer, and a metal layer positioned between the base material layer and the resin layer. The resin layer is disposed so as to face the power generator and contains a halogen-containing polymer.