Covalent interfacial coupling of vanadium nitride with nitrogen-rich carbon textile boosting its lithium storage performance as binder-free anode

Eliminating the usage of metal current collectors and binders in traditional battery electrode configuration is an effective strategy to significantly improve the capacities of lithium ion batteries (LIBs). Herein, we demonstrate the construction of porous vanadium nitride (VN) nanosheet network in situ grown on nitrogen-rich (N-rich) carbon textile (N-C@P-VN) as lightweight and binder-free anode for LIBs. The N-rich carbon textile is used both as the current collector and host to store Li⁺, thus improving the specific capacities of binder-free VN anode and meanwhile reducing the inert mass of the whole cell. Moreover, the open spaces in carbon textile and vertically aligned pores in VN nanosheet network can not only provide an expressway for Li⁺ and e⁻ transport, but also afford more active sites. As a result, the binder-free N-C@P-VN anode maintains a specific capacity of 1,040 mAh∙g⁻¹ (or an areal capacity of 2.6 mAh∙cm⁻²) after 100 cycles at 0.1 mA∙cm⁻² in half cell. Moreover, in an assembled N-C@P-VN//LiFePO₄ full cell, it exhibits an areal capacity of 1.7 mAh∙cm⁻² after 300 cycles at 0.1 C. The synergistic strategy of N-C substrate and porous VN network could be applied to guide rational design of similar N-C@nitride or sulfide hybrid systems with corresponding sulfur-doped carbon textile as the substrate.