Enhanced Li-ion transport in divalent metal-doped Li2SnO3.

The improvement of Li-ion transport properties and doping engineering in Li-ion batteries are currently active research topics in the search for next-generation energy storage devices. In this theoretical work, the intrinsic defect formation and transport properties of divalent metal-doped Li2SnO3, which is being considered as an electrode and coating electrode material, are explored using atomistic simulations. Defect formation simulations reveal that all divalent dopants (Zn, Sc, Cd and Eu) occupy the Li site with charge compensation through Li vacancies. Molecular dynamics simulations show that the divalent dopants significantly reduce the activation energy for ionic diffusion and conduction compared to the undoped sample. The effects of both grains and grain boundaries on the Li-ion transport properties are investigated. Our calculated results demonstrate a marked improvement in the properties of Li2SnO3 that can be achieved either in current commercial and next-generation Li-ion battery technologies through divalent doping in mono- and polycrystalline Li2SnO3 samples.