废旧磷酸铁锂电池正极材料的固相可控及优化再生基础研究

In view of present hydro-leaching methods with many reaction steps, complex rules of impurity migration and transformation in the field of spent power lithium iron phosphate battery recycling, this fund research will be attached great significance on controlled and optimized regeneration by solid phase method. The cathode materials of spent lithium iron phosphate battery will be separated with current collector using solvent combined with calcinations. The effects of various factors on the cathode material separation rate will be investigated and the significance of various factors and collaborative laws will be simultaneously explored. The influences of separation process on the material properties and distribution rules of residual binders after the separation will be attached great importance to be discussed. The spent cathode materials will be regenerated by solid sintering, rules between sintering product and morphology variation will be studied under different atmosphere and different sintering procedure. Meanwhile through adding different lithium, carbon sources and doping metal elements, the changes of phase composition, grain morphology, grain size distribution at different optimized sintering conditions will be discussed respectively. With the objective regenerated lithium iron phosphate, the electrochemical performance and battery performance will be tested, thus the correlation between solid phase sintering process and the electrochemical properties of recycled materials will be revealed. The basic research of this project will provide supports for the sustainable development in the field of lithium ion batteries.

本基金针对目前废旧磷酸铁锂电池回收以湿法浸出为主、反应步骤多、杂质迁移转化规律复杂等问题，开展固相法可控及优化再生研究。拟采用溶剂结合焙烧方式分离集流体与废旧磷酸铁锂正极材料，研究各因素对正极材料分离率的影响及其显著性与协同作用规律，并重点探讨分离过程对材料特性的影响规律和残余粘结剂在分离后材料中的分布规律。拟采用固相烧结法再生废旧电池材料，研究不同气氛及不同烧结程序下，烧结产物的失重变化规律以及形貌的变化规律。重点研究残余的粘接剂在烧结过程中对再生产物的影响规律。同时，通过添加不同锂源、碳源及掺杂金属元素，探讨不同优化条件下，烧结产物的晶相组成、晶粒形貌、晶粒尺寸分布的变化规律。在此基础上研究再生的磷酸铁锂材料的电化学性能和电池性能，从而揭示固相烧结过程对再生材料电化学性能的相关性。该项目基础研究将为锂离子电池领域的可持续发展提供支持。

本基金研究针对目前废旧磷酸铁锂电池回收以湿法浸出为主、反应步骤多、杂质迁移转化规律复杂等问题，开展了固相法可控及优化再生研究。采用溶剂结合焙烧方式分离集流体与废旧磷酸铁锂正极材料，研究了各因素对正极材料分离率的影响及其显著性与协同作用规律，并重点探讨了分离过程对材料特性的影响规律和残余粘结剂在分离后材料中的分布规律。采用固相烧结法再生废旧电池材料，研究了不同气氛及不同烧结程序下，烧结产物的失重变化规律以及形貌的变化规律。重点研究了残余的粘接剂在烧结过程中对再生产物的影响规律。同时，通过添加不同锂源、碳源及掺杂金属元素，探讨了不同优化条件下，烧结产物的晶相组成、晶粒形貌、晶粒尺寸分布的变化规律；在此基础上研究再生的磷酸铁锂材料的电化学性能和电池性能，从而揭示了固相烧结过程对再生材料电化学性能的相关性。该项目基础研究为锂离子电池领域的可持续发展提供支持。