Abstract:

With the rapid growth of the demand for lithium-ion battery (LIBs), a large number of waste LIBs will be produced. If not disposed of properly, it will bring serious environmental pollution problems. The cathode materials of spent LIBs contain a large number of rare valuable metals, and the recovery of these metals will produce both environmental and economic benefits. Compared with the traditional separation, purification and recovery technologies of metal components from cathode materials, the strategy of direct regeneration of cathode materials has attracted much attention due to its advantages of simple process, low energy consumption, short recycling cycle and high added value of products. Six direct regeneration technologies for cathode materials from spent LIBs such as coprecipitation method, sol-gel method, solid phase sintering method, hydrothermal method, ion thermal/molten salt method and electrochemical repair method were reviewed and their advantages and disadvantages were also summarized. Among them, coprecipitation method and sol-gel method had some limitations in industrial application because of their relatively complex steps, high equipment requirements and reagent cost. Solid phase sintering method, hydrothermal method, ion thermal/molten salt method and electrochemical repair method had great opportunities for development because of their convenience and economy. In addition, the prospect and development trend of direct recycling of cathode materials from spent LIBs were prospected in order to provide reference for the research in the field of spent LIBs recycling.

Key words: lithium-ion batteries (LIBs), cathode materials, direct regeneration, recycling

摘要：

随着锂离子电池（LIBs）需求量的急剧增长，必将产生大量废旧LIBs，如若处置不当，将带来严重的环境污染问题。废旧LIBs的正极材料中含有大量稀缺有价金属，对这些金属进行回收会产生环境和经济的双重效益。相较于传统的正极材料中金属组分的分离纯化回收技术，正极材料直接再生的策略因其具有工艺简单、能耗低、回收周期短、产品附加值高等优势而备受关注。本文综述了共沉淀法、溶胶-凝胶法、固相烧结法、水热法、离子热/熔盐法和电化学修复法6种废旧LIBs正极材料直接再生技术及其优缺点。其中共沉淀法和溶胶-凝胶法因其相对复杂的步骤、较高的设备要求和试剂成本，在工业化应用中具有一定的局限性；固相烧结法、水热法、离子热/熔盐法和电化学修复法因其便捷性和经济性，具有巨大的发展机会。同时展望了废旧LIBs正极材料直接再利用的前景和发展趋势，旨在为废旧LIBs回收领域研究提供参考。

关键词: 锂离子电池（LIBs）, 正极材料, 直接再生, 回收