Facile and economical synthesis for "plum pudding"-shaped porous LiFePO 4 /carbon composites for lithium ion batteries†
Facile and economical synthesis for "plum pudding"-shaped porous LiFePO 4 /carbon composites for lithium ion batteries†
复制标题
DOI：
10.1039/c4ra05342g
复制
发表时间：
2014-08
期刊：
影响因子：
3.9
通讯作者：
Hairong Xue;Jianqing Zhao;Tao Wang;Hu Guo;Xiaoli Fan;Jianping He
中科院分区：
文献类型：
--
作者：
Hairong Xue;Jianqing Zhao;Tao Wang;Hu Guo;Xiaoli Fan;Jianping He
以廉价的Fe 3+盐为原料，采用一步干球磨法，在碳热还原的辅助下，制备了“葡萄干布丁”状多孔LiFePO 4/C锂离子电池电极材料。与水球磨样品相比，干法球磨有利于LiFePO 4在干燥和后续热处理过程中的均匀形核。该材料显示出丰富的LiFePO 4纳米球（约200 nm）均匀地嵌入3D多孔碳结构中，作为由于干球磨过程而互连的导电框架。干磨样品具有纳米级活性电极材料（平均尺寸分布为约200 nm），具有增加的结晶度、高表面积（高达140 m2 g-1）和增强的电子电导率，有助于提高电池的倍率性能。这种“葡萄干布丁”状多孔LiFePO 4/C电极材料在0.1 C放电速率下的容量达到157.4 mA h g−1（理论容量的92.6%），并且在100次循环后达到实际充电容量154.4 mA h g−1。
A facile and economical template-free method has been developed to prepare “plum pudding”-shaped porous LiFePO4/C electrode materials for lithium ion batteries, which are synthesized by a one-step, dry ball milling with inexpensive Fe3+ salt as the raw material assisted by carbothermal reduction. Compared with a sample by ball milling with water, dry ball milling was beneficial to homogeneous nucleation of LiFePO4 in drying and subsequent thermal treatment processes. This material shows plentiful LiFePO4 nanospheres (∼200 nm) uniformly lodged in the 3D porous carbon architecture as an interconnected conductive framework due to the dry ball milling process. The dry-milling sample possessed nanoscale, active electrode materials (an average size distribution of ∼200 nm) with increased crystallinity, high surface area (up to 140 m2 g−1) and enhanced electronic conductivity contribute to improve the rate capability of the battery. The capacity of this “plum pudding”-shaped porous LiFePO4/C electrode materials achieved 157.4 mA h g−1 (92.6% of theoretical capacity) at the 0.1 C discharge rate and the practical charge capacity, 154.4 mA h g−1, has been achieved after 100 cycles.