While electric vehicles certainly are more eco-friendly than their fuel-burning counterparts, their battery packs still aren't as recyclable as they could be. A new process could help, by more efficiently extracting reusable materials from old lithium-ion batteries.
The technique was developed by scientists from Britain's University of Leicester and University of Birmingham, as part of the UK-based Faraday Institution's ReLiB (Recycling of Lithium-ion Batteries) project.
It's intended to one day replace existing recycling processes, in which batteries are typically either fed into a shredder or placed in a high-temperature reactor. According to the Faraday Institution, not only are such approaches physically and chemically complex, but they're also energy-intensive, plus they're inefficient at harvesting reusable materials from the batteries.
The new technique involves feeding the metal-foil electrodes from lithium-ion batteries into a machine, where a device known as a sonotrode subjects them to pulses of focused ultrasound. Doing so causes the electrodes' coatings of active materials to delaminate from the underlying aluminum or copper base.
As a result, both the base metals and the active materials (such as lithium, nickel, manganese and cobalt) are recovered in a purer and more easily recyclable form. Importantly, the process is also reportedly much more energy-efficient than conventional techniques, and is claimed to be a whopping 100 times quicker.
"It essentially works in the same way as a dentist's ultrasonic descaler, breaking down adhesive bonds between the coating layer and the substrate," says the lead scientist, U Leicester's Prof. Andy Abbott. "It is likely that the initial use of this technology will feed recycled materials straight back into the battery production line. This is a real step change moment in battery recycling."
The Faraday Institution is currently negotiating with several recycling companies and battery manufacturers, with an eye towards commercially licensing the system. Plans call for a technology demonstrator to be set up at an industrial site later this year.
A paper on the research was recently published in the journal Green Chemistry.
