The electrochemical performance of transition metal and graphene added Li3V2(PO4)3 cathode material for Li-ion Batteries

• A transition metal and graphene added Li3V1.9M0.1(PO4)3/graphene composite was synthesized.
• The LVP composite decreased their primary particle size in the range of 19.9–29.1 µm.
• The conducting matrix in LVP plays a critical role in decreasing the charge transfer resistance.

In this paper, a transition metal and graphene-added Li3V1.9M0.1(PO4)3/graphene (LVP–M–G, M=Ag, Ni, Ti, and Zr) composite as a cathode material for lithium ion batteries (LIBs) was synthesized by a simple sol–gel method. The monoclinic structure and morphology of as synthesized composites were observed by a power X-ray diffraction (XRD) and a scanning electron microscopy (SEM). The content of carbon was about 1.5 wt% in the LVP composite measured by a CHNS Elemental Analyzer. An electrochemical performance of the LVP–M–G was also evaluated by a galvanostatic charge/discharge, a cycling performance, and an electrochemical impedance spectroscopy (EIS), respectively. The introduction of both transition metal and graphene in the LVP exhibited smaller particle size, higher discharge capacity, and lower charge transfer resistance compared to the pristine LVP.