A Na/MnO 2 Primary Cell Employing Poorly Crystalline MnO 2

Abstract

© The Author(s) 2015. Presently Li/MnO2is one of the widely used primary battery for a variety of applications. As the global resources for Na are plentiful in relation to those for Li, Na/MnO2primary battery is expected to be an economical, viable alternate to Li/MnO2system. But marginal inferior properties of Na/MnO2, which arise due to the differences in properties between Li and Na, are inevitable. In the present work, Na/MnO2and Li/MnO2laboratory scale primary cells in non-aqueous electrolytes are assembled and their electrochemical properties are studied in similar experimental conditions. The MnO2used for these studies is prepared from KMnO4and it is in amorphous state. The discharge behavior of Na/MnO2cell is similar to that of Li/MnO2cell, but with nominal voltage less by about 0.35 V, as expected. The specific capacity of amorphous MnO2is 300 mAh g-1in both Na/MnO2and Li/MnO2cells. On heating the as prepared amorphous MnO2at temperature range 300-800°C, it converts to crystalline α-MnO2. The capacity of crystalline MnO2is significantly less than the amorphous MnO2. The results suggest that Na/MnO2is a viable, economical alternate to Li/MnO2primary cell.