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.

Resources

• 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