Novel multi-valent rechargeable ion battery: An organic nickel ion battery with Li3V2(PO4)3 cathode

Organic nickel ion battery using Ni2+ as a charge carrier has yet to be explored due to the lack of workable electrolytes and high-performing Ni2+ storage cathode materials to couple with the nickel metal anode. Herein, a feasible rechargeable organic nickel ion battery with an ether base electrolyte is demonstrated for the first time, in which Li3V2(PO4)3 and nickel foam as cathode and anode materials, respectively. The Li3V2(PO4)3 can demonstrate a high reversible specific capacity of 124 mAh g−1 at the rate of 1C and a stable cycle performance with 84% capacity retention after 50 cycles. In addition, a reversible insertion and extraction of Ni2+ ions into the cathode structure is confirmed by XRD, XPS, and EDX studies. Finally, using in-situ X-ray diffraction technology and Rietveld refinement, the reaction mechanism and structural changes during the cycle process are analyzed in detail. Therefore, the results provide an avenue to explore the organic nickel ion battery as a novel energy storage technique for renewable energies.