Dendrite-Free Lithium Deposition and Stripping Regulated by Aligned Microchannels for Stable Lithium Metal Batteries

Li metal is the ultimate choice for the anode in next-generation high energy density rechargeable batteries. However, undesired dendrite growth, dead Li formation, and a large volume change of the lithium metal anode lead to severe safety hazards such as short-circuiting, fire, or even explosion. Graphene oxide (GO) in large areas has been prepared as the Li metal host via a continuous centrifugal casting method. Aligned microchannels are then fabricated in it by a simple punching method using 3D printed templates. The GO matrix effectively regulates the lithium plating/stripping behavior while the aligned channels uniformly distributes the Li-ion flux and provides short Li-ion diffusion paths. The Li/ holey GO composite is flexible with a controllable thickness from 50 to 150 mu m, which corresponds to capacities from 9.881 to 27.601 mAh cm(-2). As a result, the anode has a low overpotential of 30 mV after 100 h, a high capacity of approximate to 3538 mAh g(-1) (91.4% of the theoretical capacity), and a superior rate ability of up to 50 C with a LiFePO4 cathode. The holey GO/Li electrode is also paired with other cathodes and used in pouch cells, indicating its suitability for various high-energy battery systems.

Automated summary

This study reports a graphene oxide (GO)-based lithium metal composite electrode, which achieves safe and efficient lithium metal anode by regulating lithium plating/stripping behavior and providing short lithium ion diffusion paths.