Short-cut and high-efficiency process to recycle copper from spent lithium-ion battery

Abstract

The booming flourish of information communication technology and electric vehicle industry has resulted in plenty of spent lithium-ion battery (LiB). Its recycling is recognized as the vital approach for resource sustainability and environmental improvement. However, the conventional recycling process was much complicated with a low recycling efficiency. We chose ionic liquid as heat medium to melt the binder and separate copper foil and anode material. Theoretical analysis based on Fourier’s law was adopted to determine the heat transfer mechanism of cathode material and to examine the relationship between heating temperature and retention time. All the experimental and theoretic results show that peel-off rate of copper foil from anode materials could reach 95% when major process parameters were controlled at 180°C heating temperature, 350 r/min agitator rotation, and 30 min retention time. The obtained results further imply that the application of ionic liquid for recycling copper and anode materials from spent LiBs is short cut and highly efficient, regardless of the application source of the LiBs or the types of anode material. The proposed process will smooth the high recycling rate for copper and aluminum, and enable the closed-loop supply chain for spent lithium-ion battery.