Pollutant control and material conversion of the waste graphite recovered from spent lithium-ion batteries: Preparation of building composite materials

The development of sustainable methods for the recycling and disposal of spent lithium-ion batteries (LIBs) has become a research priority. A large amount of waste graphite containing metals, such as Ni, Co, and Cu, was produced in the recycling process of LIBs. It was classified as hazardous waste due to its high metal leaching concentration and requires safe disposal. In this study, the concentration leaching of Ni, Co, and Cu was inhibited to less than 2 mg/L in the toxicity characteristic leaching procedure through the preparation of concrete composite materials. It showed that 1% graphite incorporation can increase compressive strength by 7.75% and stiffness by 4.53% after 7 days of curing. Scenario and cost-effect analysis showed that under the optimistic scenario, the net income of 2400 yuan per ton can be achieved through the disposal subsidy and product income. This study provides a solution with both environmental and economic benefits for the safe disposal of waste graphite and promotes the collaborative development of LIBs recycling and green building materials.