Monday, 14 October 2019
Grand Ballroom (The Hilton Atlanta)
There is a critical impediment to the practical use of Li-ion batteries (LIBs) at low temperature conditions owing to the sluggish diffusion-controlled intercalation mechanism. Moreover, the metallic Li-plating issue on the graphite anode surface at low temperature results in the capacity deterioration and short circuits due to the dendrite growth. The promising strategy to resolve these hindrances is the transition of the charge storage mechanism from the diffusive intercalation to the surface-controlled capacitive charge storage mechanism that has fast charge storage kinetics. Herein, we assembled the structure-controlled 3D crumpled graphene electrode. We employ an aerosol drying process to synthesize the structure-controlled 3D crumpled graphene electrode by controlling the stacking process of graphene sheets. We first identify the key processing parameters that can control the stacking process of the graphene sheets, assembling structure-controlled 3D crumpled graphene with superior charge storage performance. Then, we quantitatively evaluate the portion of the surface-controlled and the diffusion-limited charge storage mechanisms of the graphene anodes as a function of potential and temperature. Based on this approach, the 3D structure of the graphene assembly is further optimized to maximize the low-temperature charge storage performance through the effective utilization of the surface-controlled charge storage mechanism.
