Maximizing Lithium–Air Battery Performance with Polystyrene Based Membranes in Humid Environments

Abstract

The lithium–air battery (LAB) is considered the most promising battery type due to its significantly high theoretical energy density, which is comparable to that of gasoline. Most LAB research takes place in pure oxygen environments, as operating them under normal conditions with moisture raises safety concerns. This study focuses on creating polystyrene (PS) based membranes with added graphite to enhance their properties. The quantity of graphite ranges from 0 to 1 wt.% of PS, and the resulting membrane undergoes characterization using Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), scanning electron microscopy (SEM), water contact angle (WCA), and moisture transmission rate (MTR). The investigation reveals that the 0.7 wt.% graphite infused PS membrane performs efficiently and is subsequently employed in LAB. Additionally, the use of MnO₂ as a catalyst in the cathode material is explored through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), showing promising results. When tested in a moist gas environment alongside the optimal membrane, the LAB behaves similarly to LAB without a membrane, akin to its performance in a pure oxygen setting.