Moving towards a circular economy in battery recycling
Every year, millions of smartphones are upgraded and tossed aside — and with them, billions of old lithium batteries that typically end up in landfills or incinerators. But a team of researchers from Shenyang Agricultural University in China may have found a much better use for them.
Their new method takes discarded mobile phone batteries and combines them with lignin — a byproduct of the paper and biofuel industries — to create a high-performance electrode material for sodium-ion batteries. It’s a circular economy win on two fronts: tackling e-waste and giving industrial waste a meaningful second life simultaneously.
The process uses hydrothermal synthesis to extract nickel and cobalt from old batteries, then fuses these metals with carbon derived from lignin. The result is a composite material that punches well above its weight. During lab testing, the electrode achieved an initial discharge capacity exceeding 1,000 milliampere hours per gram — and crucially, it held up even under high power demands.
So why does this matter beyond the clever recycling angle? Sodium-ion batteries have long been seen as a promising alternative to lithium-ion technology. Sodium is far more abundant and cheaper than lithium, making it an attractive option for large-scale energy storage in electric vehicles and power grids. The main sticking point has always been finding efficient electrode materials — and this research takes a direct swing at that problem.
The study, published in the journal BiocharX, still has some distance to cover before it becomes commercially viable. Scaling the process from a lab setting to industrial production is never straightforward. But if it gets there, the implications are significant: cheaper batteries built from waste materials, less e-waste polluting the environment, and a more sustainable supply chain for the clean energy transition.
It’s a reminder that some of the most promising solutions to tomorrow’s energy problems might already be sitting in your junk drawer.
This topic was featured in Great News podcast episode 34.
Source: Interesting Engineering
