Crumpled Graphene balls makes better batteries

•Crumpled graphene particles can readily assemble to yield a scaffold
•The scaffold can stabilize scalable Li loading within tolerable volume fluctuation
•High Coulombic efficiency and plating/stripping capacity were achieved

Context and Scale
With its high theoretical capacity and low electrochemical potential, Li would be the ideal anode for Li-ion batteries. However, practical use of the Li anode has been hindered by its tendency for dendritic growth, which leads to unstable solid electrolyte interphase, volume fluctuation, and even shorting of the battery. Here we report an effective scaffold based on crumpled paper ball-like graphene particles. Since they do not aggregate, crumpled graphene balls can readily form a closely packed, continuous solid, which has highly uniform thickness and pore-size distribution. They are lithiophilic and can support fast Li-ion diffusion. Indeed, crumpled paper ball-like graphene particles have scalable Li loading up to 10 mAh cm−2 within tolerable volume fluctuation. High Coulombic efficiency of 97.5% over 750 cycles (1,500 hr) was achieved. Plating/stripping Li up to 12 mAh cm−2 on crumpled graphene scaffold does not experience dendrite growth.

Summary
With its high theoretical capacity and low electrochemical potential, Li metal itself would be the ideal anode for Li-ion batteries. However, practical use of the Li anode has been hindered by its tendency for dendritic growth, which leads to unstable solid electrolyte interphase, volume fluctuation during cycling, and even shorting of the battery. This problem can be solved by employing a conducting, lightweight, and lithiophilic scaffold that can stabilize high loading of Li during cycling and avoid its dendritic filament growth. Here we report that crumpled paper ball-like graphene particles can readily assemble to yield a scaffold with scalable Li loading up to 10 mA hr cm−2 within tolerable volume fluctuation. High Coulombic efficiency of 97.5% over 750 cycles (1,500 hr) was achieved. Plating/stripping Li up to 12 mA hr cm−2 on crumpled graphene scaffold does not experience dendrite growth.

Joule Journal – Crumpled Graphene Balls Stabilized Dendrite-free Lithium Metal Anodes