Co3(PO4)2-Coated LiV3O8 as positive materials for rechargeable lithium batteries

• Published in: Electronic materials letters 2012, 8(4), , pp.411-415
• Main Authors: Xie, Ling-Ling, You, Li-Qin, Cao, Xiao-Yu, Zhang, Chao-Feng, Song, Da-Wei, Qu, Ling-Bo
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed Matter Physics; Materials Science; Nanotechnology; Nanotechnology and Microengineering; Optical and Electronic Materials; 전자/정보통신공학
• ISSN: 1738-8090; 2093-6788
• DOI: 10.1007/s13391-012-2082-2

Co 3 (PO 4 ) 2 -coated LiV 3 O 8 has been successfully synthesized and used as positive material for rechargeable lithium batteries by a facile liquid phase method. The as-prepared powders were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and the galvanostatic discharge/charge experiments. As-prepared Co 3 (PO 4 ) 2 -coated LiV 3 O 8 forms a good layered structure with a poor cyrstallinity. SEM reveals that Co 3 (PO 4 ) 2 -coated LiV 3 O 8 has uniform particle distribution and reduced particle size when compared with bare one. The Co 3 (PO 4 ) 2 coating layer is about 33–59 nm forming a continuous lumps attached to LiV 3 O 8 particle surface. Co 3 (PO 4 ) 2 -coated LiV 3 O 8 electrode shows increased capacity and more stable cycling. The first and 35th discharge capacities of the Co 3 (PO 4 ) 2 -coated LiV 3 O 8 electrode are 322.8 mAh g −1 and 235.7 mAh g −1 in the range of 4.0–1.8 V at a current rate of 30 mA g −1 , respectively. The improved electrochemical performance is assigned to the greatly reduced LiV 3 O 8 particle with uniform morphology. Co 3 (PO 4 ) 2 -coating further benefits the phase transitions of LiV 3 O 8 during discharge/ charge while preventing parasite reactions between electrode surface and electrolyte.