Exploration of a Na3V2(PO4)3/C –Pb full cell Na-ion prototype

Abstract

Recent research focusses typically on sodium-ion half cells, and the progress of high performance and cost-effective full cells remains a critical obstacle to commercialize sodium-ion batteries. Here, we rationally design a full sodium-ion battery based on carbon coated Na3V2(PO4)3 (NVP-C) cathode and Pb anode materials. Carbon coated NVP is prepared via easy and one-step solid-state method. With 8 wt% carbon content, the obtained NVP-C core-shell structure provides an excellent reversible capacity of 104 mAh/g at C/10 rate, approaching towards its theoretical capacity. The NVP-C electrode even at a high 5 C rate delivers a primary reversible capacity of 87 mAh/g with 99.9% capacity retention almost after 3500 cycles. As an anode, Pb delivers an initial reversible capacity of 477 mAh/g at a fixed current density of 13 mA/g with a good cyclability and capacity retention of 98.5% over 50 cycles. The full cell constructed from the as-prepared materials exhibits a preliminary reversible capacity of 233 mAh/g at C/10 rate. In addition, the good rate capability including discharge energy density in the range of 170–180 Wh/kg makes the full cell a potential candidate in practical sodium-ion battery application. The excellent electrochemical behavior with simple, low-cost properties of fabricated full cell mark it as attractive option for high-energy energy storage applications.