The Influence of Copper Current Collector Crystal Orientation on Long and Short Term Lithium Metal Plating

Lithium metal is a practical anode of choice for beyond lithium ion battery technologies due to its high capacity and low potential. However, recharging (plating) lithium metal has proven difficult because of the formation of lithium dendrites and an unstable solid electrolyte interphase (SEI). Both are root causes of poor performance and safety issues such as internal short circuits, fire, and thermal runaway. To mitigate these undesirable qualities of lithium anodes for secondary battery applications, more uniform lithium plating is necessary. Here we investigate the performance and lithium morphology on single crystal (111, 100, and 110) and polycrystalline copper current collectors to control Li plating, especially in early cycles. The 111 orientation was determined by cryo scanning electron microscopy (with focused ion beam cross sections) and energy-dispersive X-ray spectroscopy to lead to a more compact lithium morphology and uniform SEI. Platting/stripping experiments supported that this improved morphology also manifested in a greater coulombic efficiency in early cycles in lithium-copper cells.