Electrochimica Acta, Vol.180, 507-513, 2015
Porous spherical LiMnPO4 center dot 2Li(3)V(2)(PO4)(3)/C cathode material synthesized via spray-drying route using oxalate complex for lithium-ion batteries
Porous spherical LiMnPO4 center dot 2Li(3)V(2)(PO4)(3)/C composite was synthesized innovatively via spray-drying route using oxalate complex. X-ray diffraction patterns and energy dispersive X-ray results revealed that the composite was composed of LiMnPO4 and Li3V2(PO4)(3). Scanning electron microscopy results revealed the porous spherical structure, and transmission electron microscopy (TEM) results exhibited that the surface of the microsphere was coated with carbon layer of about 5.1 nm thickness. The mutual doping phenomenon between LiMnPO4 and Li3V2(PO4)(3) was also confirmed by high resolution TEM and Fourier transform observation. Porous spherical LiMnPO4 center dot 2Li(3)V(2)(PO4)(3)/C delivered an initial capacity of 132.6 mAh g(-1) at 0.1 C and noticeably enhanced high rate capacities at 1, 3 and 10 C. Compared with solid spherical LiMnPO4 center dot 2Li(3)V(2)(PO4)(3)/C, cycle performance, high-rate performance and lithium ion intercalation performance of porous spherical LiMnPO4 center dot 2Li(3)V(2)(PO4)(3)/C were all significantly improved. (C) 2015 Elsevier Ltd. All rights reserved.
Keywords:Lithium ion batteries;Spray-drying;Porous spherical structure;Lithium manganese phosphate;Lithium vanadium phosphate