Salt-tethered nanoparticles in solvent: A potential high conductivity, high lithium transference number electrolyte system

Improving the lithium transference number in electrolytes, while maintaining high ionic conductivity, is crucial for reliable and high-performing lithium-ion battery technologies. In this work, using computer simulations, we model a relatively new class of electrolyte system, reported in a recent work [Chem. Mater. 2013, 25, 6, 834-839], wherein nanoparticles cofunctionalized with polymeric ligands and tethered lithium salts, are dispersed in a solvent host. We employ a sequential combination of Molecular Dynamics and kinetic Monte Carlo simulations, to study ion transport in this system. Our results are qualitatively consistent with the experimental findings. Specifically, we explain the interesting dependence of ionic conductivity on nanoparticle composition and anion chemistry. Further, we predict significant improvement in conductivity with high dielectric constant solvents. These results suggest that such electrolyte systems can potentially exhibit high conductivity, along with high lithium transference number.