Green Large-Scale Preparation of Na<sub>3</sub>V<sub>2</sub>(PO<sub>4</sub>)<sub>3</sub> with Good Rate Capability and Long Cycling Lifespan for Sodium-Ion Batteries
Wenxue Yan, Xuejie Wang, Yang Han, Jiaguo Yu, Liuyang Zhang, Tao Liu
Abstract
Sodium-ion batteries are recognized as a more cost-effective choice for large-scale energy system storage compared to lithium-ion batteries. Na 3 V 2 (PO 4 ) 3 exhibits a structure as a Na superionic conductor, displaying outstanding thermal stability and notable energy density. Whereas conventional preparation process of Na 3 V 2 (PO 4 ) 3 emits harmful gases such as nitrogen oxides and sulfur dioxides, which not only pollute the environment but also escalate material production costs, rendering it unsuitable for large-scale industrial applications. In this work, we successfully synthesized a carbon-coated Na 3 V 2 (PO 4 ) 3 material via spray drying using vanadium oxide (V 2 O 5 ), oxalic acid (H 2 C 2 O 4 ), and sodium dihydrogen phosphate (NaH 2 PO 4 ). Importantly, our production process does not involve the emission of nitrogen oxides and sulfur dioxides, effectively mitigating environmental pollution. The NVP/C–Na sample demonstrates a noteworthy initial capacity of 109.3 mA h g –1 at 1 C. After 5000 cycles at a high rate of 10 C, the material exhibits exceptional cycling stability, maintaining a substantial capacity of 88.4 mA h g –1 . These results underscore its excellent electrochemical performance of the NVP/C–Na, indicating its promising potential for large-scale energy storage in sodium-ion batteries.