Recycling of spent lithium-ion batteries (LIBs) has emerged as an inevitable trend in promoting environmental sustainability and resource conservation. Lithium iron phosphate (LiFePO or LFP) battery, renowned for its unique stability and favorable price, has been the predominant focus for lithium-ion battery manufacturers, consequently resulting in a surge in the number of spent LIBs. In view of the failure mechanism, the direct regeneration technology presents a potential strategy for the closed-loop recycling of LFP. The aim is to retain the high added value and revitalize optimal state of the spent cathode materials through a non-destructive process that maximizes efficiency and ensures desirable profits. Hence, the existing technical challenges and recent progress in the separation pretreatment are reviewed and summarized. Subsequently, the current direct regeneration methods and advanced upcycling techniques for spent LFP cathode are outlined, along with an appraisal of their respective advantages and disadvantage. Specifically, a comprehensive analysis of environmental and economic benefits derived from three presentative examples is highlighted compared to traditional metallurgy process. The review also aims to provide an overview on direct regeneration of spent LFP cathode, making it favorable for further industry adoption.

中文翻译：

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废磷酸铁锂正极直接再生的挑战和前景

废旧锂离子电池（LIB）的回收已成为促进环境可持续发展和资源节约的必然趋势。磷酸铁锂（LiFePO或LFP）电池以其独特的稳定性和优惠的价格而闻名，一直是锂离子电池制造商的主要关注点，导致废锂离子电池数量激增。鉴于失效机制，直接再生技术为磷酸铁锂的闭环回收提供了一种潜在的策略。目的是通过非破坏性工艺保留高附加值并恢复废正极材料的最佳状态，从而最大限度地提高效率并确保理想的利润。因此，对分离预处理现有的技术挑战和最新进展进行了回顾和总结。随后，概述了当前废旧磷酸铁锂正极的直接再生方法和先进的升级回收技术，并评估了它们各自的优缺点。具体而言，与传统冶金工艺相比，重点对三个代表性实例的环境和经济效益进行了综合分析。该审查还旨在提供废磷酸铁锂阴极直接再生的概述，使其有利于进一步的行业采用。