2024年9月24日出版的《美国化学会杂志》发表了中国科学家的一项最新研究成果。清华大学深圳国际研究生院的周光敏课题组，通过表面催化修复实现了废层状氧化阴极的高效再生。

据介绍，直接回收技术具有经济效益和环境友好性，被认为是下一代废旧锂离子电池回收技术。对于废层状氧化物正极材料，颗粒表面附近不可逆向岩盐结构的相变阻碍了锂离子的再嵌入，从而阻碍了锂补偿过程完全恢复成分缺陷和修复失效结构。

研究组引入了一种过渡金属氢氧化物前驱体，利用其在退火过程中产生的表面催化活性，将岩盐结构转化为层状结构，为锂离子提供快速迁移途径。材料修复和合成过程共享相同的加热程序，使废阴极和添加的前驱体经历拓扑转变，形成目标层状氧化物。

这种再生材料表现出优于商用阴极的性能，在1.3 Ah的袋状电池中循环1000次后，仍能保持其初始容量的88.4%。技术经济分析强调了表面催化修复，相对于火法和湿法修复的环境和经济优势，表明其具有实际应用潜力。

附：英文原文

Title: Surface Catalytic Repair for the Efficient Regeneration of Spent Layered Oxide Cathodes

Author: Nengzhan Zheng, Haocheng Ji, Junxiong Wang, Mengtian Zhang, Linlin Wei, Ruyu Shi, Kai Jia, Xinru Wu, Xiao Xiao, Zhaofeng Zhuang, Bo Li, Hui-Ming Cheng, Guangmin Zhou

Issue&Volume: September 24, 2024

Abstract: Direct recycling is considered to be the next-generation recycling technology for spent lithium-ion batteries due to its potential economic benefits and environmental friendliness. For the spent layered oxide cathode materials, an irreversible phase transition to a rock-salt structure near the particle surface impedes the reintercalation of lithium ions, thereby hindering the lithium compensation process from fully restoring composition defects and repairing failed structures. We introduced a transition-metal hydroxide precursor, utilizing its surface catalytic activity produced during annealing to convert the rock-salt structure into a layered structure that provides fast migration pathways for lithium ions. The material repair and synthesis processes share the same heating program, enabling the spent cathode and added precursor to undergo a topological transformation to form the targeted layered oxide. This regenerated material exhibits a performance superior to that of commercial cathodes and maintains 88.4% of its initial capacity after 1000 cycles in a 1.3 Ah pouch cell. Techno-economic analysis highlights the environmental and economic advantages of surface catalytic repair over pyrometallurgical and hydrometallurgical methods, indicating its potential for practical application.

DOI: 10.1021/jacs.4c10107

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c10107