Porous Co₂VO₄ Nanodisk as a High-Energy and Fast-Charging Anode for Lithium-Ion Batteries

High-energy-density lithium-ion batteries (LIBs) that can be safely fast-charged are desirable for electric vehicles. However, sub-optimal lithiation potential and low capacity of commonly used LIBs anode cause safety issues and low energy density. Here we hypothesize that a cobalt vanadate oxide, Co₂VO₄, can be attractive anode material for fast-charging LIBs due to its high capacity (~ 1000 mAh g^-1) and safe lithiation potential (~ 0.65 V vs. Li⁺/Li). The Li⁺ diffusion coefficient of Co₂VO₄ is evaluated by theoretical calculation to be as high as 3.15 × 10^-10 cm² s^-1, proving Co₂VO₄ a promising anode in fast-charging LIBs. A hexagonal porous Co₂VO₄ nanodisk (PCVO ND) structure is designed accordingly, featuring a high specific surface area of 74.57 m² g^-1 and numerous pores with a pore size of 14 nm. This unique structure succeeds in enhancing Li⁺ and electron transfer, leading to superior fast-charging performance than current commercial anodes. As a result, the PCVO ND shows a high initial reversible capacity of 911.0 mAh g^-1 at 0.4 C, excellent fast-charging capacity (344.3 mAh g^-1 at 10 C for 1000 cycles), outstanding long-term cycling stability (only 0.024% capacity loss per cycle at 10 C for 1000 cycles), confirming the commercial feasibility of PCVO ND in fast-charging LIBs.