Lithium electrodeposition for energy storage: filling the gap between theory and experiment

Lithium (Li) metal has been considered a promising anode material for high-energy-density rechargeable batteries, but its utilization is impeded by the nonuniform electrodeposition during the charging process which leads to poor cycling life and safety concerns. Thus, understanding the electrodeposition mechanism of Li-metal anode is of great importance to develop practical engineering strategies for rechargeable Li-metal batteries. The electrodeposition of Li is controlled by both thermodynamic and kinetic factors, such as the solvation free energy of Li-ions, the Li nucleation, the surface diffusion of Li atom, and the strength of the interaction between Li-ion and the electrolyte anion. The scale of the whole process from the Li-ion reduction to the growth of a Li nucleus goes from sub-nanometer up to a few micrometers, which poses an outstanding challenge to both experiments and simulation. In this perspective, we discuss the top-down, the bottom-up, and the middle-way approaches to this challenge and the possible synergies between them