Recovery of Electrode Materials from a Spent Lithium-Ion Battery through a Pyrolysis-Coupled Mechanical Milling Method

The recycling of spent lithium-ion batteries is in urgent demand, while organic binders hinder the recovery of electrode materials. In this study, a pyrolysis-coupled mechanical milling method was proposed to recover electrode materials from a spent lithium-ion battery. The results showed that pyrolysis removed the organic binders inside the spent battery, and after the mechanical milling, the total recovery ratio of electrode materials increased from 38.91 to 93.70% under the conditions with a pyrolysis temperature of 650 degrees C, milling duration of 15 min, and grinding ball ratio of 2:3. Meanwhile, the recovery ratios of cathode metals and anode graphite reached 97.89 and 86.90%, respectively. On the basis of the characterization results, it was determined that the chemical valences of the recovered metals were reduced by the reductive pyrolysis gases, whereas the graphitization degree of the recovered graphite decreased dramatically as a result of the presence of pyrolysis char. The findings presented herein offered a simple and eco-friendly option for the recovery of electrode materials from a spent lithium-ion battery as well as recycling noble metals and graphite resources.