A team from Shandong University of Technology in China has proposed a new process to recycle anode materials from spent lithium-ion batteries and to reuse the graphite.
The graphite and copper foil of the anode are separated by an electrochemical method: copper foil coated graphite is the negative electrode, the inert electrode is the positive electrode, the electrolyte solution is Na2SO4. The graphite thoroughly separates from the copper foil; simultaneously, lithium was dissolved into the solution.
The copper foil can be directly reused without further treatment, the Cu2+ and Li+ in the electrolyte can be recovered by precipitation.
The purity of recovered graphite is about 95%, and the graphite can be reused to prepare the anode materials for lithium-ion batteries that exhibit excellent cycling stability and rate capability. The first discharge and charge specific capacities at a rate of 0.1 C are 427.81 mA h g−1 and 350.47 mA h g−1, respectively. The coulombic efficiency after the second cycle is observed to be about 98%.
A paper on the work is published in the Journal of Power Sources.
Ning Cao, Yali Zhang, Linlin Chen, Wei Chu, Yaoguo Huang, Yun Jia, Ming Wang (2020) “An innovative approach to recover anode from spent lithium-ion battery,” Journal of Power Sources, doi: 10.1016/j.jpowsour.2020.229163