EAGER: CET: Advancing Sustainable Cathode Recycling of Spent Lithium-Ion Batteries using Deep Eutectic Solvents

这个早期概念的探索性研究（EAGER）赠款奖是为了回应亲爱的同事信23-109，作为NSF范围内的清洁能源技术倡议的一部分。可靠和强大的能源储存系统在国家向碳中和经济过渡中发挥着至关重要的作用。锂离子电池在能源生产和储存领域带来了范式转变，特别是在电动交通领域。然而，到2030年，每年产生的废旧锂离子电池废物预计将超过500万吨，全球只有5%被回收利用。虽然现有的回收工艺已经在工业上实施，但它们面临着重大挑战，例如高能耗、低金属分离效率、有限的可回收性和大量废物的产生。为了促进循环经济，建立废物资源化供应链，必须开发高效和可持续的锂离子电池回收冶金技术。EAGER研究项目的目标是通过开发基于使用低共熔溶剂的良性浸出和电沉积的下一代回收技术，推进废旧锂离子电池的回收。该项目将开发一个闭环过程，最大限度地减少废物，同时最大限度地提高金属回收率。该项目将实现废旧锂离子电池的可持续回收，从而节省能源，减少污染物，加速电气化。此外，研究的内在跨学科性质将促进多样化的培训环境，为研究生和本科生提供培训和指导的机会。通过本研究获得的知识将被纳入现有的课程，从而将实验设计方法扩展到教育活动中，每年有80多名本科生和研究生受益。本研究项目将阐明使用低共熔溶剂回收电池金属的机制和化学，并提供回收和再利用报废产品的创新方法。综合研究方法需要实验测试，操作诊断和统计分析，以开发可持续的电池回收工艺，包括在深共熔溶剂中的浸出和电沉积。该过程的物理化学机制沿着其对过程效率的影响将通过各种条件下的溶解度测量和配位络合物鉴定来揭示，并辅以形态表征、定量元素图谱和微观结构分析。这些努力将提供有价值的见解，各种深共晶溶剂的溶剂化能力，在深共晶溶剂电解质中的电池金属的传输性能，以及在不同的深共晶溶剂环境中的电池金属的配位行为。通过探索不同的溶液化学和微调工艺操作参数，将实现更高的选择性和产品纯度。该项目还将揭示反应途径、速率决定步骤和表观活化能，并提供一个强大的框架，用于根据操作参数准确预测过程响应，从而促进从废锂离子电池中有效回收金属。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

This EArly-concept Grants for Exploratory Research (EAGER) award is made in response to Dear Colleague Letter 23-109, as part of the NSF-wide Clean Energy Technology initiative. Reliable and robust energy storage systems play a crucial role in the national transition towards a carbon-neutral economy. Lithium-ion batteries have brought a paradigm shift in the field of energy generation and storage, particularly in electric transportation. However, the annual generation of spent lithium-ion battery waste is projected to exceed 5 million tons by 2030, with only 5% being recycled worldwide. While existing recycling processes have been implemented industrially, they face significant challenges such as high energy consumption, low metal separation efficiency, limited recyclability, and substantial waste generation. To promote a circular economy and establish a waste-to-resource supply chain, it is imperative to develop efficient and sustainable metallurgical technologies for lithium-ion battery recycling. The objective of this EAGER research project is to advance the recycling of spent lithium-ion batteries through the development of next-generation recycling technologies based on benign leaching and electrodeposition using deep eutectic solvents. This project will develop a closed-loop process that minimizes waste while maximizing metal recovery. The project will enable sustainable recycling of spent lithium-ion batteries thereby saving energy, reducing pollutants, and accelerating electrification. Furthermore, the intrinsically interdisciplinary nature of the research will foster a diverse training environment, providing opportunities for training and mentorship for both graduate and undergraduate students. Knowledge gained through this study will be incorporated into existing courses, thus extending the experimental design approach to education activities, and benefiting more than 80 undergraduate and graduate students annually.This research project will elucidate the mechanisms and chemistry involved in the recovery of battery metals using deep eutectic solvents and provide an innovative approach to recycling and reusing end-of-life products. The integrated research approach entails experimental testing, operando diagnostics, and statistical analysis, to develop a sustainable battery recycling process comprising leaching and electrodeposition within deep eutectic solvents. The physicochemical mechanisms of the process along with their impact on process efficiency will be revealed through solubility measurements and coordination complex identification under various conditions, complemented by morphological characterization, quantitative elemental mapping, and microstructural analysis. These efforts will offer valuable insights into the solvating capabilities of various deep eutectic solvents, transport properties of battery metals in deep eutectic solvent electrolytes, and coordination behaviors of battery metals in diverse deep eutectic solvent environments. Enhanced selectivity and product purity will be realized by exploring different solution chemistries and fine-tuning process operating parameters. The project will also unveil reaction pathways, rate-determining steps, and apparent activation energies, and provide a robust framework for accurately predicting process responses based on operating parameters, thus facilitating effective metal recovery from waste lithium-ion batteries.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.