Luqi Zhang, Hongpeng Gao, Yuwei Zhu, Ich Tran, Wei Tang, Jiao Lin, Anthony U. Mu, Junlin Wu, Wei Li, Dennis Nordlund, Linqin Mu, Zheng Chen
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引用次数: 0
Abstract
Direct regeneration offers a promising alternative to recycling End-of-Life (EoL) batteries by restoring metal elements and preserving the material structure, yet scaling these technologies to handle practical cathode black mass (CBM) with impurities remains challenging. This study investigates the evolution of impurities, including aluminum (Al), polyvinylidene difluoride (PVDF) binder, and residual carbon (C), during direct recycling of spent LiFePO4 (LFP) cathodes and their impact on electrochemical performance. Using various ex situ and in situ analyses, it is shown that the formation of lithium fluoride (LiF) during the traditional direct recycling process hinders lithium diffusion and deteriorates the reversible capacity. To address this major challenge, the combination of pH-controlled hydrothermal purification and the two-step sintering process is proposed effectively to regenerate spent LFP cathodes, eliminating the negative effect of Al and fluorine (F) impurities while mitigating any potential impacts of carbon residuals. The regenerated LFP from spent CBM achieves superior performance, retaining 152.5 mAh g−1 at 0.1 C and 133 mAh g−1 at 1 C with 98.7% capacity retention after 200 cycles. This approach is further validated using three distinct waste feedstocks from battery modules, enhancing impurity management and scalability in direct recycling. These findings present a sustainable and economically viable solution for large-scale LFP regeneration.
通过恢复金属元素和保留材料结构,直接再生为回收报废电池(EoL)提供了一种很有前途的替代方案,但扩展这些技术来处理含有杂质的实际阴极黑质量(CBM)仍然具有挑战性。本研究研究了废LiFePO4 (LFP)阴极直接回收过程中,铝(Al)、聚偏氟乙烯(PVDF)粘结剂和残碳(C)等杂质的演变及其对电化学性能的影响。通过各种非原位和原位分析表明,在传统的直接回收过程中,氟化锂(liff)的形成阻碍了锂的扩散,并降低了可逆容量。为了解决这一重大挑战,提出了ph控制水热净化和两步烧结工艺相结合的有效再生废LFP阴极,消除了Al和氟(F)杂质的负面影响,同时减轻了碳残留的任何潜在影响。废CBM再生的LFP具有优异的性能,在0.1℃和1℃下分别保持152.5 mAh g - 1和133 mAh g - 1,在200次循环后保持98.7%的容量。该方法使用来自电池模块的三种不同的废物原料进一步验证,增强了杂质管理和直接回收的可扩展性。这些发现为大规模LFP再生提供了可持续和经济可行的解决方案。
期刊介绍:
Established in 2011, Advanced Energy Materials is an international, interdisciplinary, English-language journal that focuses on materials used in energy harvesting, conversion, and storage. It is regarded as a top-quality journal alongside Advanced Materials, Advanced Functional Materials, and Small.
With a 2022 Impact Factor of 27.8, Advanced Energy Materials is considered a prime source for the best energy-related research. The journal covers a wide range of topics in energy-related research, including organic and inorganic photovoltaics, batteries and supercapacitors, fuel cells, hydrogen generation and storage, thermoelectrics, water splitting and photocatalysis, solar fuels and thermosolar power, magnetocalorics, and piezoelectronics.
The readership of Advanced Energy Materials includes materials scientists, chemists, physicists, and engineers in both academia and industry. The journal is indexed in various databases and collections, such as Advanced Technologies & Aerospace Database, FIZ Karlsruhe, INSPEC (IET), Science Citation Index Expanded, Technology Collection, and Web of Science, among others.