Methyl Methacrylate (MMA)-Grafted Polypropylene (PP) Separator for Rechargeable Lithium Metal Battery

In this article the polypropylene (PP) separator grafted by methyl methacrylate (MMA) functional groups with plasma technique has been primarily investigated. The MMA groups are expected to form a stable interface with lithium metal electrode. In addition, the effect of the surface functional group MMA on the graphite and the LiFePO4 electrode has been also primarily examined. The cyclic voltammetry (CV) tests have exhibited faster deposition/dissolution reaction kinetics of lithium on stainless steel electrode. The impedance measurements have shown a smaller interface resistance between the electrolyte (PP-MMA separator) and the lithium metal electrode. The interface reaction kinetics of the electrolyte (separator)/lithium electrode can be effectively enhanced by the MMA surface functional groups. It is also found that the existence of the MMA-groups at the separator surface can increase the reversible capacity of both LiFePO4 and graphite electrode. (c) 2012 The Electrochemical Society. All rights reserved.