With the increased demand of renewable energy, its production, transportation and storage must be environmentally benign and sustainable. Lithium-ion batteries (LIBs) have been widely used in electric vehicles and renewable electricity grids due to their high energy density. However, LIBs reach their lifetime after a few years of service due to performance degradation. From an economic point of view, reuse of the battery metals used (e.g., lithium, cobalt, nickel) can significantly reduce their cost because a large portion of the cost is in the cathode electrode material (30-40%). From an environmental point of view, the organic solvent and metal wastes generated from disposal of used batteries require treatment and final storage. For economic and environmental benefits, it is desired to recycle, reuse and re-manufacture LIBs for sustainable energy storage. Through a close collaboration with the industrial partner MeecoTech, this GOALI award focuses on fundamental understanding and resolving the compositional and structural defects in high energy LIB cathodes during operation and the impacts of regeneration processes. Such knowledge can be used to develop an energy-efficient, non-destructive process towards a sustainable LIB re-use process technology. This project will also integrate graduate, undergraduate and pre-college education and training by providing facilities, tools, practical examples, hands-on laboratory experiences and industrial internships. A strong engagement in enhancing STEM diversity will also be made through broad-based outreach activities in the San Diego area.
The primary goal of this project is to establish a systematic understanding of the formation mechanisms of the compositional and structural defects in a variety of high-energy cathode materials during cell operation, as well as understanding of their evolution during non-destructive regeneration processes. Towards this goal, the specific objectives of the project include: (1) to characterize the compositional and structural formations during LIB cycling using model cathode materials; (2) to characterize and understand the compositional and structural evolution of degraded LIB cathodes during non-destructive regeneration; and (3) to fabricate new cells and fully characterize the electrochemical properties of regenerated electrode active particles based on the efficient non-destructive method. The results will provide fundamental knowledge of the correlation between their composition/structure defects and redox properties and stability. Such knowledge can not only be applied as the basis to further develop a general technology to allow an environmental benign, low-cost, and robust non-destructive strategy for effective regeneration of used LIB but also provide guidelines for better design of LIB active particles.
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.
