废旧镍钴锰酸锂正极材料的固相直接修复再生技术

Solid-phase direct regeneration technique of spent nickel-cobalt-manganese lithium cathode materials

近年来,随着新能源汽车领域的快速发展,锂离子动力电池的出货量不断增加,三元锂离子电池因其优异的高能量密度性能已被广泛应用于便携式电子设备和新能源汽车等领域。随着锂离子电池即将迎来“退役”高峰,镍钴锰酸锂正极材料作为锂离子电池中最为关键的电极材料之一,其高效绿色循环利用具有重要的资源、环境、经济及战略意义。目前传统的镍钴锰酸锂正极材料回收技术以火法冶金和湿法冶金为主,这些方法可以从废弃的正极材料中提取高附加值金属,但普遍存在污染大、能耗高、循环周期长等问题。固相直接修复再生技术能够直接对废旧正极材料进行修复,实现正极材料的结构、组分及电化学性能的有效恢复,因其具有工艺简单、绿色高效等优势而受到广泛的关注。围绕固相直接修复再生技术,系统阐述镍钴锰酸锂正极材料的失效机制和修复机理,详细分析焙烧温度、焙烧气氛以及补锂工艺对固相修复再生镍钴锰酸锂正极材料结构和性能的影响及其作用机理,并指出了目前固相直接修复再生技术存在的问题,展望了该技术的未来前景。

In recent years,with the rapid development in the field of new energy vehicles,the produc‐tion shipment of lithium-ion power batteries has continued increasing.Among them,ternary lithium-ion batteries,due to their outstanding high-energy density performance,have been widely applied in portable electronic devices and the new energy vehicle.With the coming of the retirement peak of lithium-ion battery,lithium nickel cobalt manganese oxide cathode material,as one of the most critical electrode materials in lithium-ion batteries,has important resource,environmental,economic,and strategic significance for its efficient and green recycling.Presently,traditional recycling tech‐niques for spent lithium nickel cobalt manganese oxide cathode materials are mainly based on pyro‐metallurgy and hydrometallurgy.These methods extract high-value metals from discarded cathode materials.However,they commonly suffer from issues such as substantial pollution,high energy con‐sumption,and long process cycle times.The solid-phase direct restoration and regeneration technique offer a means to directly restore the depleted cathode materials,effectively reinstating their structure,composition,and electrochemical performance.Its advantages is that that the process is simple,effi‐cient and environmental friendly,and has received widespread attention.This paper focused on the solid-phase direct restoration and regeneration technique,systematically elucidating the failure mechanisms and restoration principles of lithium nickel cobalt manganese oxide cathode materials.It extensively analyzed the impact and mechanisms of calcination temperature,roasting atmosphere,and lithium fill processes on the structure and properties of solid-phase restored and regenerated lithium nickel cobalt manganese oxide cathode materials.Moreover,it highlighted the existing issues in the current solid-phase direct restoration and regeneration technique was prospected while provid‐ing an outlook on the future prospect of the technology.