Rapid recycling of spent lithium-ion batteries using microwave route

The discarded lithium-ion batteries containing valuable metals and graphite are excellent resources inthe context of urban mining. In the present study, electrode sheets of mixed spent lithium-ion batterieswere crushed, sieved, followed by froth flotation for physical separation of graphite values. The currentstudy investigates the carbothermal reduction of the active cathode material in a microwave furnaceunder ambient conditions using recovered graphite. The microwave response of as such active material (mixed anode and cathode), and separated active cathode material at 800 W, 2.5 GHz, was compared. The magnetic product at the optimum condition (850.C, 30 % C, 10 min) consists of 73 % Co, 13 % Mn, 6 % Ni, 8 % O and saturation magnetization of 108 emu/g, and lithium extraction rate: 93 %. Higher recovery of metal and graphite values are obtained by processing of separatedcathode material compared to assuch active materials. The effect of microwave treatment was found successful for metal dissolution in the hydrometallurgical route also. The average activation energy is 72 and 94 kJ/mol for separated and as such active materials, respectively. The cost calculations show that the process is economical. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Automated summary

This study focused on utilizing discarded lithium-ion batteries for valuable metal and graphite resources through processes like microwave treatment and froth flotation, achieving successful separation and recovery with high metal and graphite value recovery rates.