High tap-density Li3V2(PO4)3/C composite material synthesized by sol spray-drying and post-calcining method

The cathode material Li3V2(PO4)3/C composite is prepared by a sol spray-drying and post-calcining technology. XRD results show that the material is a well crystallized single phase. SEM and TEM observations reveal that the Li3V2(PO4)3/C powders have the spherical shape with a uniform particle size distribution from submicron to micron scale, and there is a homogenous carbon layer of 2.5 nm thick on the particle surface. The tap density of Li3V2(PO4)3/C is as high as 1.61 g cm−3. The electrochemical performance of the composite is excellent. At 0.1 C rate, the Li3V2(PO4)3/C sample exhibits high initial discharge capacities of 127.41 mAh g−1 between 2.5 and 4.3 V, and 161.30 mAh g−1 between 2.5 and 4.5 V, respectively. Even at a rate of 10 C, the composite can still deliver high discharge capacities of 102.27 and 111.64 mAh g−1 in the potential regions of 2.5–4.3 V and 2.5–4.5 V, respectively.

► The cathode material Li3V2(PO4)3/C is prepared using a novel sol spray-drying and post-calcining method. ► The Li3V2(PO4)3/C powders exhibit a high tap density of 1.61 g cm−3. ► The sample shows excellent rate capability and cycle performance.