Pd/ MnO₂ air electrode catalyst for rechargeable lithium/air battery

The oxidation of a carbon binder that occurred during a charge in a carbon- MnO₂ air electrode for a Li-air battery resulted in an excessively high charge potential of 4.2 V. The air electrode activity for the Li-air battery was studied on various metals or metal oxides and the mixture of Pd and MnO₂ shows the high activity to oxidation and reduction of Li to form Li₂ O₂ or Li₂ O, respectively. Although the discharge capacity decreased, the application of Pd/ MnO2 without a carbon binder for the air electrode is effective to decrease the charge potential and to improve the energy efficiency from 60 to 89%.