高温固相修复再生磷酸铁锂正极材料研究进展

Research progress of lithium iron phosphate cathode materials regenerated by high temperature solid phase method

磷酸铁锂电池作为广泛应用的锂离子电池之一,其关键电极材料的高效回收循环利用在资源、环境、经济等方面具有重要的战略意义。高温固相修复技术能够实现磷酸铁锂正极材料短流程、低成本、高效率、绿色环保的循环利用,获得了广泛的关注和研究。针对高温固相修复再生磷酸铁锂正极材料,介绍了此类材料的电化学性能失效机理,从锂补充、缺陷修复和强化锂的迁移等方面对磷酸铁锂正极材料的修复机理进行了分析;阐述了焙烧温度、保温时间、补锂量等修复再生工艺参数对高温固相法修复磷酸铁锂正极材料的影响;分析了表面包覆和离子掺杂对提升磷酸铁锂正极材料电化学性能的影响和机理;并对高温固相修复法修复磷酸铁锂正极材料的可控制备、杂质控制和材料改性等方面的未来前景进行了展望。

As one of the widely used lithium ion batteries,the efficient recycling of the key electrode materials for lithium iron phosphate has important strategic significance in resources,environment and economy.High-temperature solid-state method,with characteristics such as short process,low cost,high efficiency and environmentally friendly,can directly regenerate the lithium ion phosphate cathode materials which has attracted great attention.In this review,the failure mechanisms of electrochemical properties of lithium iron phosphate cathode materials are introduced,and the repair mechanisms of lithium iron phosphate cathode materials are analyzed from the aspects of lithium replenishment,defect repair and enhancement of the lithium ions migration.The effects of regeneration process parameters such as calcination temperature,calcination time and lithium replenishment amount on the performance of lithium iron phosphate cathode materials are described.The modification method including surface coating and ion doping are introduced for the improvement of electrochemical performance of lithium ion phosphate cathode materials.Finally,the future prospects of controlled preparation,impurity control and material modification of regenerated lithium iron phosphate cathode materials are also proposed.