In Singapore and China, researchers are using fruit peel waste to recycle old lithium batteries. The method involves using orange peels to recover precious metals from battery waste, which could then be used in the production of new batteries. The work was done by a collaboration between Nanyang Technological University and NTU Singapore
“Current industrial recycling processes of e-waste are energy-intensive and emit harmful pollutants and liquid waste, pointing to an urgent need for eco-friendly methods as the amount of e-waste grows. Our team has demonstrated that it is possible to do so with biodegradable substances,” Professor Madhavi Srinivasan, co-director of the NTU Singapore-CEA Alliance for Research in Circular Economy (NTU SCARCE) lab, said in a statement.
The method involved drying and grinding the orange peel into a powder, then adding citric acid. The sugars, flavonoids, and phenolic acids in the mixture were able to extract 90% of cobalt, lithium, nickel and manganese from a spent lithium ion battery. The researchers then used the recovered materials to make a new battery, which showed similar capacity to a new battery.
“This waste-to-resource approach could also potentially be extended to other types of cellulose-rich fruit and vegetable waste, as well as lithium-ion battery types such as lithium iron phosphate and lithium nickel manganese cobalt oxide. This would help make great strides towards the new circular economy of e-waste, and power our lives in a greener and more sustainable manner,” adds Madhavi.