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.

中文翻译：

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用于废层状氧化物阴极高效再生的表面催化修复


直接回收因其潜在的经济效益和环境友好性而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，颗粒表面附近向岩盐结构的不可逆相变阻碍了锂离子的重新嵌入，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。我们引入了过渡金属氢氧化物前体，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体能够经历拓扑转变，形成目标层状氧化物。这种再生材料表现出优于商业阴极的性能，并且在 1.3 Ah 软包电池中循环 1000 次后仍保持其初始容量的 88.4%。技术经济分析强调了表面催化修复相对于火法冶金和湿法冶金方法的环境和经济优势，表明了其实际应用的潜力。