Highly Reversible Li Plating Confined in Three-Dimensional Interconnected Microchannels toward High-Rate and Stable Metallic Lithium Anodes

Practical application of metallic Li anode in Li-ion batteries has been restricted because of dendrite growth of Li which induces poor stability and safety issues. Despite various hosts for Li having been developed to address these issues, it is still a challenge to achieve highly reversible and stable stripping/plating behavior of Li, especially at high-rate conditions. Herein, we propose a simple method of incorporating Li in commercial carbon fiber cloth (CFC) to realize high-rate and stable metallic Li anodes by confining stripping/plating of Li in microchannels of ZnO-decorated CFC (CFC/ZnO) and dissipating high current densities through conductive carbon fiber networks. The symmetrical cell using this novel anode can run stably for over 1800 h (900 cycles) under 1 mA cm–2 and even 320 h (800 cycles) at 5 mA cm–2, which has rarely been achieved previously through structural evolution of Li-metal anode. When it is paired with commercial activated carbon, the as-made Li-ion capacitor coin cell can deliver high-rate capability (up to 30 A g–1) and long-term cycling stability for over 5000 cycles at 10 A g–1, and a large pouch cell can operate as ultrafast charge (∼1 min) battery with high-energy density of ∼50 W h kg–1.