Abstract: An electrode material includes an active material particle and a solid electrolyte particle. The solid electrolyte particle includes Li, M, and X, wherein M is at least one selected from the group consisting of metal elements excluding Li and metalloid elements, and X is at least one selected from the group consisting of F, Cl, Br, and I. The ratio R1 of the volume of the active material particle to the sum of the volume of the active material particle and the volume of the solid electrolyte particle is greater than or equal to 10% and less than 65% when expressed as percentage. The ratio R2 of the average particle diameter of the active material particle to the average particle diameter of the solid electrolyte particle is greater than or equal to 0.5 and less than or equal to 3.4.

Abstract: A battery includes a positive-electrode layer, a negative-electrode layer, and an electrolyte layer between the positive-electrode layer and the negative-electrode layer, wherein the negative-electrode layer includes a negative-electrode active material and a first solid electrolyte, the electrolyte layer contains a second solid electrolyte, the negative-electrode active material contains Li, Ti, and O, the first solid electrolyte contains a crystalline phase assigned to a monoclinic crystal and contains Li, M1, and X1, wherein M1 denotes at least one of metal elements and metalloid elements other than Li, and X1 denotes at least one of F, Cl, Br, and I, and the second solid electrolyte contains a crystalline phase assigned to a trigonal crystal and contains Li, M2, and X2, wherein M2 denotes at least one of metal elements and metalloid elements other than Li, and X2 denotes at least one of F, Cl, Br, and I.

Abstract: A negative-electrode material includes a negative-electrode active material and a solid electrolyte. The negative-electrode active material contains Li, Ti, M1, and O, wherein M1 denotes at least one selected from the group consisting of metal elements and metalloid elements other than Li and Ti. The solid electrolyte contains Li, M2, and X, wherein M2 denotes at least one selected from the group consisting of metal elements and metalloid elements other than Li, and X denotes at least one selected from the group consisting of F, Cl, Br, and I.