Synthesis and Performance Evaluation of a Solid Electrolyte and Air Cathode for a Rechargeable Lithium-Air Battery

Abstract

A tri-layered solid electrolyte and an oxygen permeable solid air cathode for lithium-air battery cells were synthesized in this investigation. Detailed fabrication procedures for solid electrolyte, air cathode and the assembly of real-world lithium-air battery cell are described. Fabrication of real-world lithium-air button cells was performed using the synthesized tri-layered solid electrolyte, an oxygen permeable air cathode, and a metallic lithium anode. The lithium-air button cells were tested under dry air with 0.1mA∼0.2mA discharge/charge current at different temperatures. It was found that interfacial contact resistances play an important role in Li-air battery cell performance. Experimental results suggested that the lack of robust interfacial contact among solid electrolyte, air cathode and lithium metal anode were the primary factors for the cell’s high internal resistances. It was also found that once the cell internal resistance issues were resolved, the discharge curve of the battery cell was much smoother and the cell was able to discharge at above 2.0V for up to 40 hours. It indicated that in order to have better performing lithium-air battery cell, interfacial contact resistances issue must be resolved very efficiently.