Designing efficient lithium metal battery using hybrid layered nanoparticles of graphene oxide and MXene and thermoplastic polyurethane-polyethylene oxide blend with high ionic conductivity and stable cycling

With continuous growth of electric vehicles, the graphite- based anodes cannot fulfill the need for higher energy densities. Lithium (\(Li\)) anode has shown to satisfy this requirement. However, the aggressive nature of \(Li\) towards liquid electrolytes and continuous growth of \(Li\) dendrites hinder its scalability. To resolve these issues, safer electrolytes including polymers and ceramics were studied. Polymer electrolytes, especially polyethylene oxide (PEO), have gained interest for their promising features. PEO shows the highest ionic conductivity (σ) among polymers but suffers from high crystallinity and temperature sensitivity of mechanical strength. On the contrary, thermoplastic polyurethanes (TPUs) show high mechanical stability at elevated temperature despite showing lower σ. Here, the two polymers were blended with the composition of TPU: PEO (30: 70) to improve PEO’s thermomechanical strength. Graphene oxide (GO) and MXene, as layered nanoparticles, were subsequently added to the blend to improve its σ and solubility of the \(LiTSI\) salt. The nanoparticles increased σ by two orders of magnitude from \({10}^{-5} S/cm\) to \({10}^{-3} S/cm\). The fast \({Li}^{+}\) transportation also led to a rise in \({Li}^{+}\) transference number from 0.329 to 0.501. The stable charge- discharge cycles also revealed the effective \({Li}^{+}\) transportation.