Magnesium-Air Fuel Cell employing environmentally benign and highly porous phyllosilicate cathode capable of storing OH - ions

Abstract: Current state-of-the-art Mg-Air batteries or Mg-Air Fuel cells are interchangeably used and involve, Mg-Anode, highly porous carbon cathode as Gas Diffusion Layer (GDL) for air to flow in the cathode and reduces as hydroxyl ion (Oxygen Reduction Reaction) (ORR). The present studies aim at the development of hydroxyl ions doped Conducting Polymer and/or mixed metal oxide phyllosilicates-based cathode for Mg-Air Fuel Cells. This cathode directly supplies OH- ions to the anode for the formation of Mg(OH) 2 and subsequently MgO without involving ORR reaction. Thus, the internal resistance associated with ORR is eliminated and improves the performance of Mg-Air Fuel Cells (FCs). Two cells were fabricated were, Cell 1 with phyllosilicates and Mg-rich phyllosilicate as the cathode and Mg(OH) 2 soaked membrane respectively, Mg anode. Cell 2 with polyaniline cathode, Mg-enriched phyllosilicates as Mg(OH) 2 soaked membrane and Mg anode. The cell configurations are Cell1: SS/Phyllosilicate//Mg(OH) 2 soaked Mg-enriched phyllosilicate membrane//Mg/Al Cell2: SS/OH - ions doped Polyaniline//Mg(OH) 2 soaked Mg-enriched phyllosilicate membrane//Mg/Al Both the cells were subjected to Galvanostatic Charge/Discharge studies at room temperature at discharge rate of 50mA/g. Cell 1 with naturally occurring mixed oxide silicates (phyllosilicates) performed efficiently then the Cell 2 to conducting polymer cathode.