Report: Sumitomo and Kyoto University developing lower temperature molten-salt battery; about 10% the cost of Li-ion
The Nikkei reports that Sumitomo Electric Industries Ltd., in partnership with Kyoto University, has developed a lower temperature molten-salt rechargeable battery that promises to cost only about 10% as much as lithium ion batteries. Sumitomo intends to commercialize the battery around 2015 and market it as an alternative to lithium-ion batteries used in automobiles and homes, according to the report.
Molten-salt batteries use highly conductive molten salts as an electrolyte, and can offer high energy and power densities. The ZEBRA battery is an example of a molten salt battery. A drawback to the general class of molten salt batteries has been high operating temperatures.
The new battery uses sodium-containing substances melted at a high temperature. The technology has been around for decades, but existing molten-salt batteries require keeping the electrolyte in a liquid state at a temperature higher than 300 C. Sumitomo Electric worked with researchers at Kyoto University to develop a sodium material that melts at 57 C.
Having roughly double the energy density of a typical lithium ion battery, the new battery would let an electric vehicle travel twice as far as a lithium ion battery of the same size. Automakers would be able to reduce the space taken up by batteries in their EVs. Molten-salt batteries also boast high heat and impact resistance and are said to be less susceptible to igniting than lithium ion batteries.
Unlike room-temperature lithium-ion battery, the new battery must be kept at 80 °C to output power; hence, Sumitomo Electric reportedly envisions it being used in applications where it is operating continuously, such as in homes and electric buses. The company and the university have applied for patents.