Lithium-sulfur battery prototypes developed by OXIS Energy have been successfully tested at 471 Wh/kg, and the U.K.-based company has also engineered a standard battery module for electric vehicles that saves Source: OXIS Energyproduction time and cost.

The company plans to demonstrate an energy density target of 500 Wh/kg within the next year. The lightweight unit has been integrated and ground-tested in an aircraft battery system and is scheduled for flight trials.

Safety is enhanced by use of a ceramic lithium sulfide passivation layer and a non-flammable electrolyte that can withstand extreme abuse situations. Finely ground sulfur and carbon are combined with a polymer binder and applied to thin aluminum foil to form the cathode. The anode composed of a thin metal lithium sheet, and the two electrodes are separated by an electrolyte based on an organic solvent with lithium salts.

Ongoing R&D focuses on increasing gravimetric energy density to 600 Wh/kg, and boosting volumetric energy density to 800 Wh/liter.