Si-Sn-M(M=Ni,Fe,Cu,Zr)体系合金相图及电化学性能

Silicon-based materials are promising anode materials for lithium ion batteries due to their high lithium storage capacity. However, the huge volume change, poor cycle life and low initial coulombic efficiency during the charge/discharge process can not meet the high energy electron equipment and power supply requirements. In the approved project, Phase diagrams and phase relations of the ternary Si-Sn-M systems will be studied experimentally. Refine the crystal structures of the compounds, calculate their atomic position, share space, combine with thermodynamic optimization to analyze their stability, look for the formation rule of the Si-Sn-M system alloy phases. Select the inert phased to buffer the volume change in the lithium insertiong-extraction process. Design the rational Si-based alloys anode material. Using XRD, SEM, electrochemical analysis motheds, deeply study the the preparation process and microstruture to influence on the electrochemical properties. Ascertain optimal preparation parameters, reveal the interaction principle between the inert and active phases. Explore the effective methods to buffer the volume change of the active phase Si and improve the cycle performance of the Si-based alloy anode. On this basis, research and develop new Si-based alloy anode for lithium ion batteries.

硅基材料具有高储锂容量，是一种非常有发展前途的锂离子负极电池材料。然而在充放电过程中体积变化大、循环寿命差、首次库伦效率低等问题导致其不能满足高能量电子设备和动力电源的要求。本项目拟开展Si-Sn-M体系相图和相关系的研究，对其化合物进行结构精修，计算各原子占位、占有率等空间结构，结合热力学优化来分析其稳定性，寻找Si-Sn-M体系合金的成相规律。遴选惰性相来缓冲锂在嵌脱过程中体积变化，合理设计Si基合金负极材料；利用XRD、SEM、电化学测试方法等分析手段深入考察Si基合金负极材料制备工艺、微观组织结构对电化学性能的影响规律，确定最佳制备工艺参数，揭示惰性相与活性相之间相互作用关系原理，探索缓冲活性相Si的体积变化和改善Si基合金负极循环性能的有效方法，获得高性能的Si基负极材料；在此基础上，研究和开发新型Si基合金负极锂离子电池。

硅基材料具有高储锂容量，是一种非常有发展前途的锂离子负极电池材料。然而在充放电过程中体积变化大、循环寿命差、首次库伦效率低等问题导致其不能满足高能量电子设备和动力电源的要求。 本项目研究了Si-Sn-M 体系相图和相关系，结合热力学优化来分析其稳定性，考察Si/Sn基合金负极材料制备工艺、微观组织结构对电化学性能的影响规律，确定最佳制备工艺参数,探索缓冲活性相Si的体积变化和改善Si基合金负极循环性能的有效方法。 在此基础上，根据我们研究发现的结果以及国际上该领域的最新进展，适当将研究内容扩展到锰酸锂正极材料、三元正极材料以及钠离子电池电极材料，分析了材料的合成、结构与电化学性能以及储能机理。