Battery

A battery, comprising:

• a positive electrode including a first positive electrode layer and a second positive electrode layer;
• a negative electrode;
• and
• an electrolyte layer located between the positive electrode and the negative electrode, wherein:
• the first positive electrode layer is located between the second positive electrode layer and the electrolyte layer,
• the first positive electrode layer includes a first positive electrode active material particle, a first solid electrolyte material particle, and a coating material located on a surface of the first positive electrode active material particle,
• the second positive electrode layer includes a second positive electrode active material particle and the first solid electrolyte material particle,
• the second positive electrode active material particle is not covered by the coating material,
• the first solid electrolyte material particle is a material represented by a composition formula LiαMβXγ,
• where
• M comprises Y and at least one selected from the group consisting of metalloid elements and metal elements other than Li,
• X is at least one kind selected from the group consisting of Cl and Br, and
• 2.5≤α≤3, 1≤β≤1.1, and γ=6 are satisfied,
• the coating material comprises an oxide solid electrolyte,
• the first solid electrolyte material particle does not include sulfur,
• the electrolyte layer includes a second solid electrolyte material particle, and
• the second solid electrolyte material particle is represented by a composition formula Li6-3dYdX′6,
• where
• 0<d<2, and
• X′ includes I and at least one kind selected from the group consisting of Cl and Br.