Role of Oxygen Mass Transport in Rechargeable Li/O2 Batteries Operating with Ionic Liquids

The use of ionic liquid (IL)-based electrolytes and porous carbonaceous cathodes is today one of the most promising strategies for the development of rechargeable Li/O2 batteries. Enhancing Li/O2 battery cyclability at high discharge rate is a key issue for automotive applications. O2 reduction at a meso-macroporous carbon electrode in N-butyl-N-methyl pyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR14TFSI):LiTFSI 9:1 is here investigated. The study demonstrates that oxygen electrode response in IL at high discharge currents is dominated by O2 mass transport in IL. A novel configuration of flow-Li/O2 battery that operates at high discharge rate is reported.