A 3D conducting scaffold with lithiophilic carbon nanoparticles for stable lithium metal battery anodes

Abstract

Li metal anode with high capacity, negative potential and low density is regarded as the most promising anode material. Unfortunately, its commercialization is greatly limited by Li dendrites. Here, a 3D carbon paper scaffold with lithiophilic carbon nanoparticles is synthesized as a Li host via the carbonization of metal-organic framework and the doping of oxygen atom. Carbon nanoparticles effectively improve the specific surface area of carbon paper that can low the local current density and provide rich internal spaces for Li reservoir. In addition, the rich lithiophilic groups (such as ZnO, nitrogen atom and oxygen atom) can regulate a uniform Li+ flux and achieve a controllable Li deposition. Based on these structural advantages, uniform nucleation and growth of Li metal have been realized. Especially, the symmetric cell renders an outstanding cyclic stability for 750 h with an ultra-low polarization voltage of 14 mV at 1 mA/cm2. Additionally, the full cell partied with a LiFePO4 cathode displays an initial specific capacity of 138.1 mAh/g, and even maintains 97.7 % capacity retention after 120 cycles at 0.5C. Therefore, this strategy presents a universal approach to construct porous hosts with abundant lithiophilic sites for long-lifespan Li metal batteries.