ERI: A Fundamental Investigation of the Effectiveness of Cathode Regeneration Process for Spent Lithium Ion Batteries

该奖项的全部或部分资金来自《2021年美国救援计划法案》(公法117-2)。随着交通和消费电子行业锂离子电池(LIB)消费量的快速增长，到2030年，需要处理或回收的废LIB数量预计将达到1100多万吨。然而，目前只有不到5%的废LIB被回收利用。因此，迫切需要开发一种环境友好和经济上可行的LiB回收技术，以管理大量危险的、尽管有价值的LiB。该项目将系统地探索一种直接回收工艺，该工艺可能最大限度地提高废弃锂离子电池的回报价值，旨在回收和再利用废锂离子电池中最有价值的正极材料，用于新的锂离子电池制造。该项目的成果将促进直接阴极回收的发展，有助于将锂离子电池废物对环境的影响降至最低，确保未来电池原材料的供应，降低锂离子电池的生产成本，并提高锂离子电池行业的可持续性。研究成果将通过学术期刊、会议、科学节和教育视频广泛传播，启发锂离子回收技术的新想法，并提高人们对锂离子回收的经济和环境影响的了解。此外，各种教育水平的学生，特别是STEM领域中代表性不足的少数群体和妇女，将通过提供动手实验室体验来接受培训。该项目的首要目标是建立对不同降解程度的废阴极直接回收的有效性的基本理解。考虑到寿命结束的锂离子电池是在不同的循环条件下产生的，废阴极预计会表现出不同程度的降解，包括锂损失、不可逆相变、晶间/晶内破裂、过渡金属的溶解和表面层的形成。为了模拟不同降解条件下的废阴极以及它们如何通过直接循环过程再生，合成了不同类型的化学脱硫化阴极，并对其进行了表征和再生。该项目旨在通过追求两个具体目标来实现其主要目标：(1)在基于溶剂的分离过程中检查化学脱硫化阴极的化学、结构和电化学稳定性；(2)确定直接阴极再生对不同降解程度的化学脱硫化阴极进行再生的有效性。这项研究的结果将促进我们对直接阴极回收背后的机理的理解，并加速工艺的开发。从这个项目中获得的新知识将为指导在不同健康状况下有效地从废锂离子电池中再生阴极材料的策略的制定奠定坚实的基础。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).As the consumption of lithium-ion batteries (LIBs) in the transportation and consumer electronic sectors rapidly increases, the volume of spent LIBs requiring disposal or recycling is expected to reach more than 11 million metric tons by 2030. However, less than 5% of spent LIBs are currently recycled. Thus, there is an urgent need to develop an environmentally friendly and economically viable LIB recycling technology to manage the hazardous, albeit valuable, large volumes of spent LIBs. This project will systematically explore a direct recycling process that could potentially maximize the return value from end-of-life LIBs, aiming to recover and reuse the most valuable cathode material in spent LIBs for new LIB manufacturing. The outcomes of the project will facilitate the development of direct cathode recycling that contributes to minimizing the environmental impacts of LIB wastes, securing the future supply of battery raw materials, lowering the cost of LIB production, and improving the sustainability of the LIB industry. The research results will be broadly disseminated through academic journals, conferences, science festivals, and educational videos, inspiring new ideas for LIB recycling technologies and improving people’s understanding of the economic and environmental impacts of LIB recycling. Furthermore, students of various education levels, especially underrepresented minorities and women in the STEM fields, will be trained by providing hands-on laboratory experiences. The overarching goal of this project is to establish a fundamental understanding of the effectiveness of direct recycling on spent cathodes at different degrees of degradation. Given the fact that end-of-life LIBs are generated under different cycling conditions, the spent cathodes are expected to exhibit various levels of degradation that involve lithium loss, irreversible phase transformation, inter/intragranular cracking, dissolution of transition metals, and surface layer formation. To simulate the spent cathodes at various degradation conditions and how they are regenerated by a direct recycling process, different types of chemically delithiated cathodes are synthesized, characterized, and regenerated. This project seeks to attain its primary goal by pursuing two specific aims: (1) to examine the chemical, structural, and electrochemical stabilities of chemically delithiated cathodes during solvent-based separation processing and (2) to determine the effectiveness of direct cathode regeneration for rejuvenating chemically delithiated cathodes at different degradation extents. The findings from this research will advance our understanding of the mechanisms behind direct cathode recycling and accelerate the process development. The new knowledge gained from this project will lay a solid foundation to guide the formulation of strategies for effectively regenerating cathode materials from spent LIBs at different state-of-health conditions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.