Electrochemical Properties of Na0.66V4O10 Nanostructures as Cathode Material in Rechargeable Batteries for Energy Storage Applications

Description: 

After commercialization in the early 1990s, rechargeable Li-ion batteries (LIBs) are being widely investigated and used as energy storage to power portable electronic devices and hybrid electric vehicles. However, due to huge demand, high cost, safety concerns, and limited and nonuniform Li resources,5 Na-ion batteries have generated considerable interest as a most promising alternative (due to the uniform distribution and abundance of Na resources in the earth crust) to the LIBs for large-scale energy storage systems. Here, We report the electrochemical performance of nanostructures of Na0.66V4O10 as cathode material for rechargeable batteries. The Rietveld refinement of room-temperature X-ray diffraction pattern shows the monoclinic phase with C2/m space group. The cyclic voltammetry curves of prepared half-cells exhibit redox peaks at 3.1 and 2.6 V, which are due to two-phase transition reaction between V5+/4+ and can be assigned to the single-step deintercalation/intercalation of Na ion. We observe a good cycling stability with specific discharge capacity (measured vs Na+/Na) between 80 (±2) and 30 (±2) mAh g−1 at current densities of 3 and 50 mA g−1, respectively. The electrochemical performance of Na0.66V4O10 electrode was also tested with Li anode, which showed higher capacity but decayed faster than Na. Using density functional theory, we calculate the Na vacancy formation energies: 3.37 eV in the bulk of the material and 2.52 eV on the (100) surface, which underlines the importance of nanostructures.

Contact details: 

Rajendra S. Dhaka

Department of Physics

rsdhaka[at]physics.iitd.ac.in