Xu Minghang, Ma Jiaojiao, Niu Guiling, Yang Hongxun, Sun Mengfei, Zhao Xiangchen, Yang Tongyi, Chen Lizhuang, Wang Changhua
School of Environmental & Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, Jiangsu, China.
Marine Equipment and Technology Institute, Jiangsu University of Science and Technology, Zhenjiang 212003, Jiangsu, China.
ACS Omega. 2020 Jul 3;5(27):16440-16447. doi: 10.1021/acsomega.0c00686. eCollection 2020 Jul 14.
Silicon suboxide (SiO ) is one of the most promising anodes for the next-generation high-power lithium-ion batteries because of its higher lithium storage capacity than current commercial graphite, relatively smaller volume variations than pure silicon, and appropriate working potential. However, the high cost, poor cycling stability, and rate capability hampered its industrial applications due to its complex production process, volume changes during Li insertion/extraction, and low conductivity. Herein, a low-cost and high-capacity SiO /C@graphite (SCG) hybrid was designed and synthesized by a facile one-pot carbonization/hydrogen reduction process of the rice husk and graphite. As an advanced anode for lithium-ion batteries, the SiO /C@graphite hybrid delivers a high reversible capacity with significantly enhanced cycling stability (842 mAh g after 300 cycles at 0.5 A g) and rate capability (562 mAh g after 300 cycles at 1 A g). The great improvement in performances could be attributed to the positive synergistic effect of SiO nanoparticles as lithium storage active materials, the in situ-formed carbon matrix network derived from biomass functioning as an efficient three-dimensional conductive network and spacer to improve the rate capability and buffer the volume changes, and graphite as a conductor to further improve the rate capabilities and cycling stability by increasing the conductivity. The low-cost and high-capacity SCG derived from rice husk synthesized by a facile, scalable synthetic method turns out to be a promising anode for the next-generation high-power lithium-ion batteries.
次氧化硅(SiO )是下一代高功率锂离子电池最具潜力的负极材料之一,因为它比目前的商用石墨具有更高的锂存储容量,与纯硅相比体积变化相对较小,且工作电位合适。然而,由于其生产工艺复杂、锂嵌入/脱出过程中的体积变化以及低电导率,高成本、较差的循环稳定性和倍率性能阻碍了其工业应用。在此,通过稻壳和石墨的简便一锅法碳化/氢还原工艺设计并合成了一种低成本、高容量的SiO /C@石墨(SCG)复合材料。作为锂离子电池的先进负极,SiO /C@石墨复合材料具有高可逆容量,循环稳定性显著提高(在0.5 A g下300次循环后为842 mAh g),倍率性能良好(在1 A g下300次循环后为562 mAh g)。性能的大幅提升可归因于作为锂存储活性材料的SiO 纳米颗粒的正协同效应、源自生物质的原位形成的碳基体网络作为高效的三维导电网络和间隔物以提高倍率性能并缓冲体积变化,以及石墨作为导体通过提高电导率进一步改善倍率性能和循环稳定性。通过简便、可扩展的合成方法由稻壳制备的低成本、高容量SCG有望成为下一代高功率锂离子电池的负极材料。