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 (similar to 1000 mAh g(-1)) and safe lithiation potential (similar to 0.65 V vs. Li+/Li). The Li+ diffusion coefficient of Co2VO4 is evaluated by theoretical calculation to be as high as 3.15 x 10(-10) cm(2) s(-1), proving (CoVO4)-V-2 a promising anode in fast-charging LIBs. A hexagonal porous (CoVO4)-V-2 nanodisk (PCVO ND) structure is designed accordingly, featuring a high specific surface area of 74.57 m(2) 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.

Automated summary

This article introduces a high-energy-density lithium-ion battery anode material Co2VO4 and its successful application in fast-charging LIBs. By designing a specific structure, the anode material possesses high capacity, safe lithiation potential, and excellent fast-charging performance.