中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 27 No. 1 January 2017 |
（1. Liaoning Key Laboratory for New Energy Battery, Dalian Jiaotong University, Dalian 116028, China;
2. School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028, China）
Abstract:In order to enhance electrochemical properties of LiFePO4 (LFP) cathode materials, spherical porous nano/micro structured LFP/C cathode materials were synthesized by spray drying, followed by calcination. The results show that the spherical precursors with the sizes of 0.5-5 μm can be completely converted to LFP/C when the calcination temperature is higher than 500 °C. The LFP/C microspheres obtained at calcination temperature of 700 °C are composed of numerous particles with sizes of ~20 nm, and have well-developed interconnected pore structure and large specific surface area of 28.77 m2/g. The specific discharge capacities of the LFP/C obtained at 700 °C are 162.43, 154.35 and 144.03 mA·h/g at 0.5C, 1C and 2C, respectively. Meanwhile, the capacity retentions can reach up to 100% after 50 cycles. The improved electrochemical properties of the materials are ascribed to a small Li+ diffusion resistance and special structure of LFP/C microspheres.
Key words: LiFePO4/C cathode; nano/micro structure; porous material; spray drying; electrochemical properties
