PNNL

Abstract

Stationary electric energy storage devices have gained increasing prominence due to great market needs, such as smoothing availability of renewable energy resources and supporting the reliability of the electric grid. Among various battery technologies, with regard to raw materials availability, sodium based batteries are better positioned than lithium batteries due to the abundant resource of sodium in the earth’s crust. However, the sodium-metal halide (Na-MH) battery, one of the most attractive stationary battery technologies, is hindered from further market penetration by fast material degradation at high operating temperature, and high manufacturing cost. This work focuses on developing advanced Na-MH battery technologies by lowering the operating temperature less than 200°C for longer cycle life and adopting low cost cathode materials. Particularly, lowering the operating temperature of a Na-MH battery opens great opportunities to adopt cost-effective sealing technologies (polymer seals) for the cell architecture to replace high cost sealing methods.