纳米自组装制备纳-微复合球形磷酸铁锂及其电化学性能研究

Lithium iron phosphate as the cathode material in the lithium-ion power battery, has prominent advantages in the production cost, the service life and safety performance. However, its wide application have always been limited by the bottlenecks of the poor charge-transfer ability and low tap-density. In this project, the nano-micro complex spherical morphology was designed to meet the morphological requirements in high conductivity (the nano-flake morphology along [010] face direction) and high tap-density (the micro spherical morphology). Here, the accurate-specific regulation mechanism and controllable fabrication method would be clarified by studying on the influence of the template molecular, solvent, concentration, temperature and other factors on the nano-micro complex structure evolution process. On the basis of the regulation mechanism, the process parameters would be further optimized to prepare the nano-micro spherical LiFePO4 sample with the exellent performance for the application in HV lithium-ion batteries. In addition, the electrochemical properties, dynamics and interfacial reaction characteristics of the nano-micro spherical LiFePO4 would also be investigated. Through the implementation of this project, it will contribute to promote the industrial technology of LiFePO4 HV lithium-ion batteries.

磷酸铁锂作为锂离子动力电池正极材料，在生产成本、使用寿命和安全性能方面具有突出的优势，但也存在电荷传输能力差、振实密度低的问题。本项目针对高导电性（沿着[010]面方向的纳米片状形貌）与高振实密度（颗粒尺寸微米化的球形形貌）在形貌要求上存在的明显矛盾，从理论上提出并设计了一种新型纳-微复合球形形貌。通过模版分子、溶剂、浓度、温度等因素对纳-微复合结构演变过程及影响规律研究，阐明纳-微结构的精确调控机理和可控构筑方法，优化目标纳-微复合球形磷酸铁锂的制备工艺参数，并对其界面反应特性、电化学性能以及在大型动力锂离子电池中的应用进行系统研究，最终获得能满足动力锂离子电池正极材料高性能需求的纳-微复合球形磷酸铁锂。通过本项目的实施，为提升我国磷酸铁锂动力锂离子电池的产业技术水平提供研究基础与技术支撑。

磷酸铁锂作为锂离子动力电池正极材料，在生产成本、使用寿命和安全性能方面具有突出的优势，但也存在电荷传输能力差、振实密度低的问题。本项目针对高导电性（沿着[010]面方向的纳米片状形貌）与高振实密度（颗粒尺寸微米化的球形形貌）在形貌要求上存在的明显矛盾，从理论上提出并设计了一种新型纳-微复合球形形貌。通过模版分子、溶剂、浓度、温度等因素对纳-微复合结构演变过程及影响规律研究，阐明纳-微结构的精确调控机理和可控构筑方法，优化目标纳-微复合球形磷酸铁锂的制备工艺参数，并对其界面反应特性、电化学性能以及在大型动力锂离子电池中的应用进行系统研究，最终获得能满足动力锂离子电池正极材料高性能需求的纳-微复合球形磷酸铁锂。通过本项目的实施，为提升我国磷酸铁锂动力锂离子电池的产业技术水平提供研究基础与技术支撑。