PFI-TT: Development of Next Generation Sulfur-based Batteries for Enhanced Run Time and Reduced Weight

Award ID: 1919177

The broader impact/commercial potential of this Partnerships for Innovation - Technology Translation (PFI-TT) project is to help all market sectors where lithium ion (Li-ion) batteries are currently used, such as aerospace & defense, transportation, medical, oil & gas, and consumer electronics. Li-ion, the highest-performing commercially available battery technology, currently accounts for 37% of the $23.5 billion battery market. However, it has currently reached the maximum performance that physics and chemistry allow. For the electric vehicle market, these performance limits would require a 1200 lb, $15,000 battery pack in an all-electric sedan, and therefore broad deployment in SUVs, pickup trucks or heavy-duty military or commercial vehicles would be commercially and economically impractical. The envisioned battery technology uses a different chemistry that potentially offers four times better storage capability than Li-ion batteries and is much lighter, leading to new economically feasible electric cars. Through unique partnerships with industry and technology commercialization, this PFI-TT project will enable testing, evaluation & refinement of the proposed technology, production scale-up and a battery prototype. The proposed project focuses on development of Li-S batteries using a commercially-viable carbonate electrolyte, the liquid responsible for transporting Li+ ions between electrodes. The past R&D efforts for Li-S use ether electrolytes that have low boiling point (~42 degrees C) making them extremely flammable and commercially non-viable. Fundamental investigations on the role of the sulfur phase in altering the reaction mechanism have led to the development of sulfur cathodes that successfully function in carbonate electrolytes - like those used in commercial Li-ion batteries for three decades - with a stable four-fold higher capacity at the material level for 1000+ cycles. This PFI-TT project will undertake development activities to reduce battery weight and increase sulfur loading based on success metrics provided by potential partners during preliminary customer discovery, with the objective to achieve four-fold improvement in the "device-level" specific capacity. The proposed technology will also eliminate dead weight (up to 25% of electrode weight) of binders and current collectors' passive components used in current devices and consequently eliminate slurry processing, a necessary processing step needed for current powder-based electrodes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NSF Program Director: Samir Iqbal