Battery

A battery comprising:

• 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 selected from the group consisting of metal elements and metalloid elements other than Li, and
• X1 denotes at least one selected from the group consisting 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 selected from the group consisting of metal elements and metalloid elements other than Li, and
• X2 denotes at least one selected from the group consisting of F, Cl, Br, and I.