Metal oxide/sulfur composite cathodes for room temperature lithium-sulfur and sodium-sulfur batteries

Alkali metal-sulfur batteries (such as Li-S and Na-S batteries) theoretically can store 3-5 times higher energy-density in comparison to commercial lithium-ion batteries. However, alkali metal-sulfur batteries are plagued with a fundamental problem of gradual dissolution of polysulfide intermediates into the liquid electrolyte from the cathode, which causes inferior cycling stability. My dissertation describes development of various metal oxide/sulfur composite cathodes to overcome the polysulfide dissolution issue. Metal oxides could immobilize the polysulfide intermediates through strong chemical interaction and thus control their gradual dissolution into. Several characterization techniques are employed to understand the chemical interaction between different metal oxides and the intermediate polysulfides.