Stabilized covalent interfacial coupling design of Li3V2(PO4)3 with carbon framework for boosting lithium storage kinetics

Abstract

Designing interfacial chemical bonds in carbon-based composite materials is of importance to optimize both electronic and ionic conduction within the entire electrode, thus achieving high performance lithium ion batteries (LIBs). Herein, a facile strategy based on the organic–inorganic hybrid hydrogel is developed to immobilize Li₃V₂(PO₄)₃ particles in the carbon framework (LVP@C), in which LVP is chemically interacting with the carbon framework via P–C and P–O–C bonds. The robust carbon framework of LVP@C not only promotes the electronic/Li⁺ transport but also provides mechanical strength to support active electrode materials, which are beneficial for alleviating the volume change and maintaining the integration of the porous framework structure during repeated cycling. As a result, LVP@C exhibits superior electrochemical activity in LIBs by maintaining the high specific capacity of 95.4 mA h g⁻¹ after 2000 cycles at a high current density of 20 C with a superior capacity retention of 88.4%. The synergistic strategy of LVP@C could be applied to guide the rational design of carbon-based composite materials with stabilized interfacial chemical bonds.