Nanocarbon Florets with Synthetically Tunable Porosity as High-Rate Anodes for Li-ion Batteries

Fast charging Li-ion batteries (LIBs) with graphite anodes presents challenges relating to Li plating on graphite, which can exothermally disrupt the solid-electrolyte interphase leading to shorter cycle life and safety concerns. Herein, we report superior high-rate Li+ storage performance in nanostructured carbon florets (NCF), that are hard carbon materials with synthetically tunable porosity and surface area, which in turn, influence Li+ diffusivity into the hierarchically porous carbon matrix. The NCF anodes with an average particle diameter of 75 nm showed excellent rate capability and Li+ cycling performance, yielding a specific capacity of ∼164 mAh/g over 1000 charge/discharge cycles at a high current density (0.74 A/g). The gradation in electrochemical properties as a function of the surface area and porosity of NCF was also established. Given their synthetic tunability and high-rate Li+ ion storage properties, NCFs can be efficient alternatives/additives to graphite anodes for fast charging applications.