Li Heteroepitaxial Deposition on Single Crystalline Ni Substrates With Enhanced Cycling Stability

Lithium (Li) metal is recognized as a highly promising anode material for next-generation high-energy-density batteries. Nonetheless, dendrite growth and low coulombic efficiency (CE) significantly impede the practical application of Li metal anodes. The deposition morphology and chemical stability of Li are intricately linked to its crystallographic orientation. This study presents a substrate engineering approach that employs single-crystalline nickel (Ni) to facilitate epitaxial Li deposition due to their excellent lattice matching. The findings reveal that the Ni(110) substrate exhibits a more pronounced heteroepitaxial effect than Ni(111). A robust {110}-textured Li deposition was prepared on Ni(110) with a uniform planar morphology due to the lower Li self-diffusion barrier on the Li(110) plane. The {110}-textured Li epitaxial deposition improves the cycling stability in Ni-Li cells and full cells. Notably, the Li||LiFePO₄ full cell utilizing the {110}-textured Li anode exhibits a high capacity retention of 109.6 mAh cm^-2 over 350 cycles at 1 C under a low negative-to-positive capacity ratio of 1.26. This investigation highlights the crucial role of substrate-induced heteroepitaxy in improving Li plating/stripping dynamics and provides insights for the development of stable Li metal anodes by crystallographic orientation modification.