Synthesis of monocrystalline lithium for high-critical-current-density solid-state batteries

Lithium metal is the Holy Grail anode material for high-energy-density batteries. Unfortunately, applications of Li metal anodes are restricted by their inherent propensity to form dendrites at practical current densities. Here we present an approach that directly converts commercial polycrystalline Li (poly-Li) into various monocrystalline Li metal anodes with single facets via a recrystallization technique. By elucidating the diffusive kinetic and mechanical characteristics of different Li facets, we reveal that monocrystalline Li(110) exhibits the lowest diffusion barrier of 0.02 eV, an order of magnitude lower than poly-Li’s 0.2 eV, and a 71% reduction in Young’s modulus from 9.42 GPa to 2.71 GPa. The critical current density can be raised by an order of magnitude in solid-state batteries using monocrystalline Li(110), and the cycling stability of Li metal batteries is extended fivefold. We envision that the manipulation of the crystal plane will effectively tackle the pivotal challenges in achieving high-energy-density batteries.