Microwave solid-state synthesis and electrochemical properties of carbon-free Li3V2(PO4)3 as cathode materials for lithium batteries

✍ Scribed by Gang Yang; Haidong Liu; Hongmei Ji; Zhongzhong Chen; Xuefan Jiang

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 873 KB
• Volume: 55
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/j.electacta.2009.11.102

✦ Synopsis

Monoclinic Li 3 V 2 (PO 4 ) 3 can be rapidly synthesized at 750 • C for 5 min (MW5m) by using microwave solid-state synthesis method. The refined cell parameters and atomic coordination of the sample MW5m show some deviations compared with those of the sample synthesized in conventional solid-state synthesis method, especially the coordinate of Li atoms. Compared with the electrochemical properties of the carbon-coating sample Li 3 V 2 (PO 4 ) 3 , the carbon-free sample MW5m presents well electrochemical properties. In the cut-off voltage of 3.0-4.3 V, MW5m sample presents a specific charge capacity of 132 mAh g -1 , almost equivalent to the reversible cycling of two lithium ions per Li 3 V 2 (PO 4 ) 3 formula unit (133 mAh g -1 ), and specific discharge capacity of 126.4 mAh g -1 . In the cut-off voltage of 3.0-4.8 V, MW5m shows an initial specific discharge capacity of 183.4 mAh g -1 at 0.1 C, near the theoretical discharge capacity. In the cycle performance, the capacity fade of Li 3 V 2 (PO 4 ) 3 is dependent on the cut-off voltage and the preparation method, more capacity lost at relatively higher charge/discharge voltage. The reasons for the excellent electrochemical properties of Li 3 V 2 (PO 4 ) 3 rapidly synthesized in microwave field are discussed in detail.