MOLTEN-SALT BATTERY, CHARGE-DISCHARGE METHOD, AND CHARGE-DISCHARGE SYSTEM

摘要

A molten-salt battery includes a positive electrode including a positive-electrode active material that reversibly occludes and releases sodium, a negative electrode including a negative-electrode active material that reversibly occludes and releases sodium, a separator disposed between the positive electrode and the negative electrode, and a molten-salt electrolyte. The molten-salt electrolyte contains an ionic liquid in an amount of 90% by mass or more. The ionic liquid contains a first salt and a second salt. The first salt contains a sodium ion which is a first cation, and a first anion. The second salt contains an organic cation which is a second cation, and a second anion. The positive-electrode active material contains a composite oxide having a layered O3-type crystal structure and containing Na, Fe, and Co. An amount of Co relative to a total of Fe and Co contained in the composite oxide is 40 to 60 atomic percent.

主权项

1. A molten-salt battery comprising:
a positive electrode including a positive-electrode active material that reversibly occludes and releases sodium; a negative electrode including a negative-electrode active material that reversibly occludes and releases sodium; a separator disposed between the positive electrode and the negative electrode; and a molten-salt electrolyte, wherein the molten-salt electrolyte contains an ionic liquid in an amount of 90% by mass or more, the ionic liquid contains a first salt and a second salt, the first salt contains a sodium ion which is a first cation, and a first anion, the second salt contains an organic cation which is a second cation, and a second anion, the positive-electrode active material contains a composite oxide having a layered O3-type crystal structure and containing Na, Fe, and Co, and an amount of Co relative to a total of Fe and Co contained in the composite oxide is 40 to 60 atomic percent.