Environmental-Friendly LiCoO2 Recycling from Libs Under the Assistance of Ultrasonic and Supercritical CO2

Wednesday, 31 May 2017
Grand Ballroom (Hilton New Orleans Riverside)
C. Dai (Harbin Institute of Technology), D. Mu (Harbin Institute of Technology, Harbin University of Commerce), and Y. Liu (Harbin Institute of Technology)
The rising demand for lithium calls for fully processing and using of all viable resources. Different processes in vogue aiming at recycling spent LIBs can be mainly divided into pyro/hydrometallurgical technologies. Pyro-processes burn off the organic toxic and flammable electrolytes and binder, while Hydro-processes may produce amounts of wastewater which contains complex chemical substances for further treatment. Herein, we aim at recovery the LiCoO2 from LIBs directly without bringing secondary pollutant. The cathode was shredded ( ~1.5 cm2 size) to separate active metal materials from aluminum foil in NMP (N-methyl-2-pyrrolidone) at room temperature under the ultrasonic assistance for 30 mins. The electrolyte and binder were dissolved in NMP, and later were recovered by Supercritical CO2 .NMP was reused and eventually recycled back by evaporation. The active materials was dried in vacuum for 12 hours at 100 ℃. XRD and SEM analysis indicated that the recycling material was LiCoO2 with high purity, and the electrochemical properties were tested by assembling coin cell batteries. The initial specific discharge capacity was more than 150mAh/g. GC-FID was investigated to reflect the unchanging composition of NMP. Our research fully care about environmental benign and economic feasibility.This technological process realizes the recycling of flammable liquid electrolyte and cathode materals and avoides the environmental harzards.