Lithium Based Ionogel as Solid State Electrolyte: Dynamics of Confined Ionic Liquid, a Neutron Diffusion Study

Obtaining solid-state electrolytes with good electrochemical performances remain challenging. Ionogels, i.e. solid host network confining an ionic liquid, are promising as they keep the macroscopic properties of the confined liquid. However, confinement of an ionic liquid can imply important changes in its molecular dynamics, depending on the route of synthesis and on the confining network. We studied this effect on an imidazolium based ionic liquid with its Lithium salt confined in a biopolymer-silica matrix. Dynamics of bulk and confined solution was probed by quasi-elastic neutron scattering (QENS). The scattering function was modeled successfully with two Lorentzian functions in both cases and revealed a weakly slowed dynamics of imidazolium-based ionic liquid inside the polymer-silica host network.