Constructing Co O Nanowires on Carbon Fiber Film as a Lithiophilic Host for Stable Lithium Metal Anodes.

Lithium metal has been considered as the most promising anode electrode for substantially improving the energy density of next-generation energy storage devices. However, uncontrollable lithium dendrite growth, an unstable solid electrolyte interface (SEI), and infinite volume variation severely shortens its service lifespan and causes safety hazards, thus hindering the practical application of lithium metal electrodes. Here, carbon fiber film (CFF) modified by lithiophilic Co O nanowires (denoted as Co O Nws) was proposed as a matrix for prestoring lithium metal through a thermal infusion method. The homogeneous needle-like Co O nanowires can effectively promote molten lithium to infiltrate into the CFF skeleton. The post-formed Co-Li O nanowires produced by the reaction of Co O Nws and molten lithium can homogeneously distribute lithium ions flux and efficaciously increase the adsorption energy with lithium ions proved by density functional theory (DFT) calculation, boosting a uniform lithium deposition without dendrite growth. Therefore, the obtained composite anode (denoted as CFF/Co-Li O@Li) exhibits superior electrochemical performance with high stripping/plating capacities of 3 mAh cm and 5 mAh cm over long-term cycles in symmetrical batteries. Moreover, in comparison with bare lithium anode, superior Coulombic efficiencies coupled with copper collector and full battery behaviors paired with LiFePO cathode are achieved when CFF/Co-Li O@Li composite anode was employed.