废旧锂电池回收过程中氟的迁移及其原位掺杂再生制备LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)正极材料  

Fluorine migration and in-situ doping for regeneration of Ni-rich LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2) cathode material from spent lithium-ion batteries

作　　者：王天宇 易晨星 葛鹏 王丽 孙伟 吴美容 张驰 杨越 Tianyu Wang;Chenxing Yi;Peng Ge;Li Wang;Wei Sun;Meirong Wu;Chi Zhang;Yue Yang(School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China;School of Chemical Engineering,Zhengzhou University,Zhengzhou 450001,China)

机构地区：[1]School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China [2]School of Chemical Engineering,Zhengzhou University,Zhengzhou 450001,China

出　　处：《Science China Materials》2023年第9期3433-3444,共12页中国科学（材料科学（英文版）

基　　金：supported by the National Natural Science Foundation of China (51904340);the Natural Science Foundation of Hunan (2021JJ2020066);the National Key Research and Development Program (2019YFC1907801, 2019YFC1907803 and 2019YFC1907804);the Central South University Innovation-Driven Research Programme (2023CXQD009)。

摘　　要：氟是废旧锂电池回收难以回避的典型杂质元素,其迁移转化行为复杂,制约了高品质正极材料的可控再生制备.本研究通过揭示废旧锂电池在热解、浸出及高镍LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)材料再生过程中氟的迁移转化规律,为氟的定向调控及材料的可控再生制备奠定理论基础实验结果表明:热解过程中部分氟(45.71%)以气态热解产物的形式释放到大气中,而另一部分氟(52.34%)则向废三元材料的晶格内发生迁移,并随着湿法浸出溶解到镍钴锰的浸出液中.浸出液中少量的氟会在共沉淀制备前驱体过程中迁移到Ni_(0.9)Co_(0.05)Mn_(0.05)(OH)2前驱体材料,并随着配锂烧结掺杂到再生LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)材料表面.进一步通过调控氟含量发现,当浸出液中氟浓度控制在0.30 g L^(-1)时,引入到再生LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)材料中的氟不仅不会引起不利相变,而且能够稳定材料结构,从而有效提升再生高镍材料的循环稳定性(1 C电流密度下循环100圈的容量保持率高达95.7%).因此,本研究不仅揭示了废旧锂电池回收过程中氟的迁移转化行为,而且可控再生制备了高性能氟掺杂高镍LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2)正极材料,为废旧锂离子电池回收过程中氟的调控提供了理论依据.Recycling of spent lithium-ion batteries(LIBs)has raised wide concerns vis-à-vis resource value and environmental protection.Benefiting from the short process and high added value of the recycled products,the regeneration of cathode materials from spent LIBs is a popular approach.However,due to the lack of studies on fluorine(F)migration and the impact thereof on recycled materials,F control relies on deep removal and becomes a considerable challenge,limiting the generation of high-quality cathode materials.Herein,the migration-transformation behaviors of F are investigated in the integrated pyrolysis-leaching-regeneration process of spent LIBs.It is indicated that 45.71%of the amount of F is released into the atmosphere during pyrolysis and some amount of F in the leaching solution is adsorbed into coprecipitated precursors through coordination with metal ions and then regularly entering the lattices of the regenerated LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2).Regarding the effects of F on the regenerated LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2),a moderate F concentration(approximately 0.30 g L^(−1))in the leaching solution can boost the regenerated LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2) material’s cycling stability(the capacity retention of 95.7%after 100 cycles at 1 C),due to the stabilizing effect of F-doping on the regenerated material’s structure.This study reveals the migration–transformation mechanisms of F during the recycling of spent LIB and provides a rational in-situ F-doping strategy for the regeneration of LiNi_(0.9)Co_(0.05)Mn_(0.05)O_(2).

关 键 词：正极材料 三元材料 废旧锂离子电池 高镍 回收过程 废旧锂电池 循环稳定性 氟掺杂 

分 类 号：X705[环境科学与工程—环境工程] TQ131.11[化学工程—无机化工]