A positive electrode material includes a positive electrode active material and a solid electrolyte. The oxidation potential of the solid electrolyte is higher than or equal to 3.9 V versus Li/Li+. The ratio of the volume of the solid electrolyte to the volume of the positive electrode material is in a range of greater than or equal to 8% and less than or equal to 25%. A battery of the present disclosure includes a positive electrode containing the positive electrode material, a negative electrode, and an electrolyte layer disposed between the positive electrode and the negative electrode.