Novel Separator for Electricity Storage Devices

Northwestern University researchers have developed a novel device to reduce thermal runaway or loss of energy through heat in lithium ion batteries. During operation as batteries discharge stored electricity some of it is lost as heat. Battery overheating can cause various devices to malfunction as well as lead to fire. Several methods for reducing thermal runaway exist but they either add complexity to the battery manufacturing process or cause damage to the battery once deployed. Professor Kung and colleagues have invented a reversible thermal control separator (RTCS) which solves both of these problems. RTCS is a graphene oxide based membrane coated with poly(sulfobetaine)polymer or PMABS. This membrane can easily be integrated into a lithium battery without the need for any additional components or changes in the manufacturing process. In laboratory tests RTCS was able to restrict ion flow at elevated temperatures indicating a reduction in thermal runaway. Applications: Lithium ion batteries