LAUSR

Abstract The study exploits the functional advantages of vanadium with variable oxidation states to extract maximum energy from Li3V2(PO4)3/HHC composite containing human hair derived carbon. Vanadium, present in the form of V3+ in Li3V2(PO4)3 stabilizes itself electrochemically as V4+ by forming LiV2(PO4)3 through oxidation in the potential range 3.0–4.5 V and as V1+ by forming Li7V2(PO4)3 due to the reduction of V3+ into V1+ in the 0.01–3.0 V region, thus qualifying LVP as a rocking chair electrode. In other words, Li3V2(PO4)3/HHC composite demonstrates itself as anode and as cathode for lithium-ion batteries. Li3V2(PO4)3/HHC cathode exhibits ultra high capacity, excellent rate capability at 50C and retains about 99% capacity up to 1000 cycles. As anode, Li3V2(PO4)3/HHC delivers a capacity of 428 mAh g−1 at 50 mA g−1 and tolerates 5 A g−1 condition up to 1000 cycles with a negligible capacity fade. The dual electrode behavior of Li3V2(PO4)3/HHC may be attributed to the unique architecture of HHC that provides high electronic conductivity, facilitates rapid diffusion of lithium ions and admits volume changes during intercalation/deintercalation. More importantly, HHC is a cheap and eco-friendly carbon additive derived from filthy human hair, which in turn offers ample scope for the commercial exploitation of title electrode.