Figure 3: FTIR measurement.
From: A Rechargeable Li-Air Fuel Cell Battery Based on Garnet Solid Electrolytes

FTIR spectra of air cathodes after the 1 st and 5th discharge (black lines) and 1st and 5th charge (red lines) at 80 °C. Regions are highlighted by the dotted lines corresponding to the peaks of Li2CO3. The spectra of pristine air cathodes, pure Li2CO3 (olive line) and Li2O2 (dark cyan line) powders are provided for comparison.