3-D Nanofilm Primary Li Air Battery

NASA requires a new primary battery capable of providing specific energy exceeding 2000Wh/kg over an operating temperature range of 0oC to 35oC with a shelf life exceeding 2 years in support of Exploration Medical Capabilities. Metal/air chemistries such as aluminum/air or lithium/air are suggested due to their high theoretical specific capacity. Recent attempts by others at Li-air batteries have provided limited energy and unacceptably poor rate performance due to their use of composite air cathodes. Such composites combine sub-optimal micro-porous powder with low-surface area, poorly distributed, un-optimized electro-catalyst and non-electrochemically contributing binder. Ionova Technologies, Inc. proposes a new Li-air battery utilizing a binderless 3-D nanofilm air cathode comprising a networked mesoporous carbon structure decorated with novel, highly reactive, ultra-high surface area catalysts. Pore size/structure and catalyst distribution are optimized to promote oxygen diffusion and to reduce pore clogging from reaction products while maximizing reaction sites to increase capacity and current density. The proposed electro-catalyst exhibits specific capacity that exceeds what has been demonstrated by other catalyst materials in the research literature. Cumulatively, the 3-D nanofilm Li-air approach is anticipated to improve energy and power densities vs. other approaches by improving discharge capacity and current density. This project will investigate the feasibility of the 3-D nanofilm approach to improve diffusion and reaction kinetics in a primary Li-air battery through modeling and materials/lab cell characterization to TRL3. TRL4 will be achieved by mid-phase II and TRL6 will be achieved by end phase II.

The commercial realization of a battery with specific energy in excess of 2000Wh/kg would permit a mass reduction of ca. 5x vs. consumer Li/MnO2 and Zn-air batteries. Such improvements may permit the 3-D nanofilm Li-Air battery to supplant Li/MnO2 and other high-energy batteries in applications such as hearing aids, consumer electronics, military communications, transportation, automated meter reading, memory backup and RFID.

For this solicitation, NASA has sought advanced high-energy battery systems for use in Exploration Medical Capabilities mission applications such as power for mobile oxygen concentrators. The commercial realization of a battery with specific energy in excess of 2000Wh/kg would permit a mass reduction of ca. 3x vs. current state of the art Li/CFx and ca. 5x vs. consumer Li/MnO2 batteries. Given the sensitivity of space flight to weight, such a high-energy battery would enable increased mission time or increased payload.