Recycling Application of Li–MnO2 Batteries as Rechargeable Lithium–Air Batteries

Graphical Never say die : Depleted Li–MnO 2 batteries could be further utilized as rechargeable Li–O 2 batteries with admitted oxygen. Thus, when the manganese oxide electrode was lithiated in situ and exposed to air (see picture), the resulting battery showed superior performance, including high capacity, a low overpotential, high rate capability, and high cycling stability. The ever-increasing consumption of a huge quantity of lithium batteries, for example, Li–MnO 2 cells, raises critical concern about their recycling. We demonstrate herein that decayed Li–MnO 2 cells can be further utilized as rechargeable lithium–air cells with admitted oxygen. We further investigated the effects of lithiated manganese dioxide on the electrocatalytic properties of oxygen-reduction and oxygen-evolution reactions (ORR/OER). The catalytic activity was found to be correlated with the composition of Li x MnO 2 electrodes (0< x <1) generated in situ in aprotic Li–MnO 2 cells owing to tuning of the Mn valence and electronic structure. In particular, modestly lithiated Li 0.50 MnO 2 exhibited superior performance with enhanced round-trip efficiency (ca. 76 %), high cycling ability (190 cycles), and high discharge capacity (10 823 mA h g carbon −1 ). The results indicate that the use of depleted Li–MnO 2 batteries can be prolonged by their application as rechargeable lithium–air batteries.