Nanoporous Graphene with Encapsulated Multicomponent Carbide as High‐Performance Binder‐Free Lithium‐Ion Battery Anodes

Abstract Metal carbides are considered attractive lithium‐ion battery (LIB) anode materials. Their potential practical application, however, still needs nanostructure optimization to further enhance the Li‐storage capacity, especially under large current densities. Herein, a nanoporous structured multi‐metal carbide is designed, which is encapsulated in a 3D free‐standing nanotubular graphene film (MnNiCoFe‐MoC@NG). This free‐standing composite anode with a high surface area not only provides more active Li + storage sites but also effectively prevents the agglomeration or detachment of active material in traditional powder‐based electrodes. Moreover, the free‐standing design does not require additional binders, conductive agents, or even current collectors when used as LIB anode. As a result, the MnNiCoFe‐MoC@NG anode exhibits a high specific capacity of 1129.2 mAh g −1 at 2 A g −1 and maintains a stable capacity of 512.9 mAh g −1 after 2900 cycles of 5 A g −1 , which is higher than most reported Mo x C‐based anodes. Furthermore, the anode exhibits superb low‐temperature performance at both 0 and −20 °C, especially at large current densities. These properties make the free‐standing anode very promising in fast charging and low‐temperature applications.