Reversible Calcium-Ion Insertion in NASICON-Type NaV<sub>2</sub>(PO<sub>4</sub>)<sub>3</sub>
Boosik Jeon, Jongwook W. Heo, Jooeun Hyoung, Hunho H. Kwak, Dongmin M. Lee, Seung‐Tae Hong
Abstract
The recent discovery of reversible plating and alloying of calcium has invoked considerable interest in calcium-based rechargeable batteries toward overcoming the limitations of conventional Li-ion batteries. However, only a few cathode materials have been tested thus far, and these exhibit low energy-storage capability and poor cyclability. Herein, the highly reversible Ca-intercalation capability of NASICON-type NaV2(PO4)3 makes it a potential cathode material for nonaqueous Ca-ion batteries, with high capacity and voltage and good cyclability (90 mA h g–1 and ∼3.4 V at 11.7 mA g–1 and 75 °C; 70 mA h g–1 and ∼3.2 V at 5.85 mA g–1 and 25 °C). Although this work shows only the capability of the cathode, not a full-cell performance, it does demonstrate experimentally that a poly-oxyanionic material can provide an outstanding host structure for Ca diffusion at room temperature with high energy-storage capability.