All-solid secondary battery with graded electrodes

An all-solid secondary battery comprising:

• a positive electrode body including a positive electrode current collector and a positive electrode active material layer that contains at least a positive electrode active material and a positive electrode electrolyte, and that is formed on the positive electrode current collector;
• a negative electrode body including a negative electrode current collector and a negative electrode active material layer that contains at least a negative electrode active material and a negative electrode electrolyte, and that is formed on the negative electrode current collector;
• and
• a solid electrolyte that is held between the positive electrode body and the negative electrode body, wherein
• in the electrode active material layer of at least one of the positive electrode body and the negative electrode body, a total content ratio, which is represented by a ratio of mass of the electrolyte contained in the electrode active material layer to mass of the active material contained in the electrode active material layer, is larger than 1;
• and
• the electrode active material layer of the at least one of the positive electrode body and the negative electrode body has a composition distribution in which a local content ratio, which is represented by a ratio of mass of the electrolyte contained in a portion of the electrode active material layer to mass of the active material contained in the portion of the electrode active material layer, increases from a solid electrolyte interface toward a current collector interface in a thickness direction of the electrode active material layer.