context: A carbon nanotube film was used as the oxygen cathode and Li foil with 0.5 mm thickness as the anode for LOBs. A glass fiber separator wetted with a 100 μL electrolyte composed of 1.0 M LiTFSI in TEGDME was employed to separate the cathode and anode. All assembled cells were measured on a LAND electrochemical testing system at 25 °C. The cycling test was conducted with the capacity limited at 1000 mA h g−1 at a current density of 300 mA g−1.
answer: oxygen 