Implications of CO2 Contamination in Rechargeable Nonaqueous Li-O2 Batteries.
In this Letter, the effect of CO2 contamination on nonaqueous Li-O2 battery rechargeability is explored. Although CO2 contamination was found to increase the cell's discharge capacity, it also spontaneously reacts with Li2O2 (the primary discharge product of a nonaqueous Li-O2 battery) to form Li2CO3. CO2 evolution from Li2CO3 during battery charging was found to occur only at very high potentials (>4 V) compared to O2 evolution from Li2O2 (∼3-3.5 V), and as a result, the presence of CO2 during discharge dramatically reduced the voltaic efficiency of the discharge-charge cycle. These results emphasize the importance of not only completely removing CO2 from air fed to a Li-air battery, but also developing stable cathodes and electrolytes that will not decompose during battery operation to form carbonate deposits.
†IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, United States.
S R
SR
Gowda
†IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, United States.|‡Phelma, Grenoble INP, Minatec, 3 Parvis Louis Néel, CS 50257, 38016 Grenoble Cedex 1, France.
A
A
Brunet
†IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, United States.
G M
GM
Wallraff
†IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, United States.
B D
BD
McCloskey