Wang Jing, Bao Wurigumula, Ma Lu, Tan Guoqiang, Su Yuefeng, Chen Shi, Wu Feng, Lu Jun, Amine Khalil
School of Materials Science and Engineering, Beijing Key Laboratory of Environmental Science and Engineering, Beijing Institute of Technology, Beijing, 100081, China.
National Development Center of High Technology Green Materials, Beijing, 100081, China.
ChemSusChem. 2015 Dec 7;8(23):4073-80. doi: 10.1002/cssc.201500674. Epub 2015 Nov 9.
Silicon monoxide is a promising anode candidate because of its high theoretical capacity and good cycle performance. To solve the problems associated with this material, including large volume changes during charge-discharge processes, we report a ternary hierarchical silicon oxide-nickel-graphite composite prepared by a facile two-step ball-milling method. The composite consists of nano-Si dispersed silicon oxides embedded in nano-Ni/graphite matrices (Si@SiOx /Ni/graphite). In the composite, crystalline nano-Si particles are generated by the mechanochemical reduction of SiO by ball milling with Ni. These nano-Si dispersed oxides have abundant electrochemical activity and can provide high Li-ion storage capacity. Furthermore, the milled nano-Ni/graphite matrices stick well to active materials and interconnect to form a crosslinked framework, which functions as an electrical highway and a mechanical backbone so that all silicon oxide particles become electrochemically active. Owing to these advanced structural and electrochemical characteristics, the composite enhances the utilization efficiency of SiO, accommodates its large volume expansion upon cycling, and has good ionic and electronic conductivity. The composite electrodes thus exhibit substantial improvements in electrochemical performance. This ternary hierarchical Si@SiOx /Ni/graphite composite is a promising candidate anode material for high-energy lithium-ion batteries. Additionally, the mechanochemical ball-milling method is low cost and easy to reproduce, indicating potential for the commercial production of the composite materials.
一氧化硅因其高理论容量和良好的循环性能而成为一种有前景的负极候选材料。为了解决与该材料相关的问题，包括充放电过程中的大体积变化，我们报道了一种通过简便的两步球磨法制备的三元分级氧化硅-镍-石墨复合材料。该复合材料由嵌入纳米镍/石墨基体（Si@SiOx/Ni/石墨）中的纳米硅分散氧化硅组成。在复合材料中，通过球磨使SiO与Ni进行机械化学还原生成结晶纳米硅颗粒。这些纳米硅分散氧化物具有丰富的电化学活性，能够提供高锂离子存储容量。此外，球磨后的纳米镍/石墨基体与活性材料良好地粘结并相互连接形成交联框架，其作为电子传输通道和机械骨架，使所有氧化硅颗粒都具有电化学活性。由于这些先进的结构和电化学特性，该复合材料提高了SiO的利用效率，在循环过程中适应其大体积膨胀，并具有良好的离子和电子导电性。因此，复合电极在电化学性能方面有显著改善。这种三元分级Si@SiOx/Ni/石墨复合材料是一种有前景的高能锂离子电池负极候选材料。此外，机械化学球磨法成本低且易于重复，表明该复合材料具有商业化生产的潜力。
