Research Projects

The rapid global adoption of lithium-ion batteries (LIBs) for renewable energy and electric vehicles has created an urgent need to manage the growing volume of spent batteries. While recycling these batteries is critical for environmental protection and resource recovery, current methods such as pyrometallurgy and hydrometallurgy remain energy-intensive, relying on harsh chemicals, and produce by-products that limit direct reuse. Many countries, including China, the United States, Japan, and Europe, have enacted regulations to improve recycling rates, but available technologies still face significant challenges related to cost, efficiency, and environmental impact. This project investigates a novel approach to recover and restore valuable cathode materials from spent LIBs using an in-liquid plasma discharge system featuring an advanced multi-needle electrode array. Cathode materials, often lithium cobalt oxide (LiCoO₂), lithium manganese oxide, and ternary compounds, contain lithium, cobalt, nickel, and manganese that are vital but increasingly scarce. Compared to other battery components such as anodes and separators, cathode materials are more complex and economically important for recycling. Low-temperature plasma technology offers a unique advantage as it generates reactive species capable of breaking down metal oxides at room temperature and atmospheric pressure, without damaging the crystal structure of the cathode material. Unlike traditional chemical methods requiring strong acids, high temperatures, and long processing times, plasma treatment uses reactive oxygen species to selectively dissolve metal ions in a cleaner, faster, and safer manner. The multi-needle array enhances plasma generation and increases interaction surface area with the cathode slurry, boosting efficiency and throughput. Although plasma-assisted recycling has been explored in limited contexts, the application of a scalable multi-needle in-liquid plasma system to directly leach metals from spent cathodes remains largely untested. By increasing the number of plasma discharge needles, this project aims to intensify reactive species production and speed metal extraction under ambient conditions, without external heating or toxic chemicals. The main goal is to optimize plasma parameters and slurry composition to maximize recovery of lithium, cobalt, nickel, and manganese while maintaining the structural integrity of cathode materials for potential direct reuse. The project will also investigate downstream metal recovery and evaluate electrochemical performance of regenerated materials. If successful, this research will provide a greener, more economical alternative to existing LIB recycling methods, contributing to sustainable resource management and circular economy practices. It will deepen scientific understanding of plasma-liquid interactions in metal extraction and pave the way for environment-friendly recycling technologies implementable on an industrial scale.