LiFePO4在碳包覆、晶格掺杂、复合改性及形貌优化方面已进行了较深入的研究，但利用晶体结构取向性和构筑同轴碳芯结构复合材料的研究还鲜见报道。本项目旨在以磁场诱导、取向生长为切入点，以结构均匀的多羟基植物纤维为基体，通过磁场诱导LiFePO4晶体择优取向生长，构筑具有结构取向的同轴碳芯结构LiFe1-xRexPO4/C复合材料，同时实现离子的快速扩散、电子的快速传输。研究LiFePO4在纤维上成核、生长情况，掌控其形貌和晶粒取向的关键技术；考察稀土金属离子掺杂对LiFePO4晶体的取向性的影响；分析LiFePO4纳米晶与无定形碳的结合方式，探讨LiFePO4纳米晶的诱导成核-取向生长机理；通过磁场控制实现复合材料在极片上的有序组装，提高其装载量；探索复合材料界面扩散及导电机制，建立界面扩散及导电模型。本项目的成功实施将为LiFePO4的改性研究提供理论指导和新的设计思路。

The modification of LiFePO4, such as carbon coating, lattice doping, multi-modification and optimization for its morphology, has been investigated deeply, but the research of its modification, utilizing the orientation of its crystal structure to construct the composite materials with coaxial carbon core structure, is rarely reported. This project aims to realize the fast diffusion of lithium ion and electron by constructing LiFe1-xRexPO4/C composite materials with a preferred structure orientation and coaxial carbon core structure, using uniform hydroxyl vegetable fibers as matrix and inducing the preferred orientation growth of LiFePO4 crystal through the magnetic field. The nucleation and growth of LiFePO4 on vegetable fibers will be investigated and the key technology of its morphology and crystal orientation will be controlled. The effect of doping rare earth metal ions on the crystal orientation of LiFePO4 will be investigated. The combination of LiFePO4 nanocrystalline and amorphous carbon will be analyzed and the induced nucleation and growth mechanism of LiFePO4 nanocrystalline will be discussed. The ordered assembly of composite materials through controlling the magnetic field will be realized to increase their loading capacity on current collector. The mechanism of interface diffusion and conduction will be explored and the model of interface diffusion and conduction will be found. The successful implementation of this project will provide theoretical guidance and new design ideas for the modification research of LiFePO4.