LONDON: UK and US researchers have found ways to recycle electric vehicle batteries that can dramatically reduce costs and carbon emissions, boosting sustainable supplies for an expected increase in demand.
The techniques, which involve recovering parts of the battery so they can be reused, would help the auto industry respond to criticism that even though electric vehicles reduce emissions over their lifespan, they start with a high carbon footprint of extracted materials.
As national governments and regions scramble to secure supplies for an expected acceleration in demand for electric vehicles, advancements could move further into the valuable supply of materials such as cobalt and carbon. nickel. They would also reduce dependence on China and difficult mining jurisdictions.
“We cannot recycle complex products like batteries the same way we recycle other metals. Shredding, mixing of battery components and pyrometallurgy destroys value,” said Gavin Harper, researcher at the Faraday Institution in Great Britain, supported by the government.
Pyrometallurgy refers to the extraction of metals at high temperatures in blast furnaces, which analysts say is uneconomical.
Current recycling methods also rely on shredding batteries into very small pieces, called black masses, which are then turned into metals such as cobalt and nickel.
A shift to a practice known as direct recycling, which would preserve components such as the cathode and anode, could significantly reduce energy waste and manufacturing costs.
Researchers at the University of Leicester and the University of Birmingham working on the Faraday Institution’s ReLib project have found a way to use ultrasonic waves to recycle the cathode and anode without shredding and have applied for patent.
The technology recovers the cathode powder composed of cobalt, nickel and manganese from the aluminum foil, to which it is glued in the manufacture of the battery. The anode powder, which would typically be graphite, is separated from the copper foil.
Andy Abbott, professor of physical chemistry at the University of Leicester, said separation using ultrasonic waves would result in savings of 60% compared to the cost of virgin material.
Compared with more conventional technology, based on hydrometallurgy, which uses liquids, such as sulfuric acid and water to extract materials, he said ultrasonic technology can process 100 times more materials from battery over the same period.
Abbott’s team manually separated the battery cells to test the process, but ReLib is working on a project to use robots to separate batteries and packs more efficiently.
As supply and scrap levels take time to increase, Abbott said he expected the technology to initially use scrap from battery manufacturing facilities as the raw material and the recycled material to be fed back into the plant. battery production.
To make recycling lithium-ion batteries profitable, without requiring disposal costs for consumers, and to encourage the growth of the recycling industry, new methods that generate higher profit margins for recyclers must be developed.Jeff Spangenberger, ReCell, Chief
In the United States, a government-sponsored project at the Department of Energy called ReCell is in the final stages of demonstrating different, but also promising, recycling technologies that refurbish the battery cathode into a new cathode. .
ReCell, led by Jeff Spangenberger, studied many different methods, including ultrasound, but focused on thermal and solvent-based methods.
“The United States doesn’t make a lot of cathodes domestically, so if we use hydrometallurgy or pyrometallurgy, we have to send the recycled material to other countries to be made into cathodes and sent back to us.” , Spangenberger said.
“To make the recycling of lithium-ion batteries profitable, without requiring disposal costs for consumers, and to encourage the growth of the recycling industry, new methods that generate higher profit margins for recyclers must be developed. “
There are challenges for direct recycling, including constantly changing chemistries, Spangenberger said. “ReCell is working on the separation of different cathode chemistries.”
Early electric vehicle battery cells typically used a cathode with equal amounts of nickel, manganese, cobalt, or 1-1-1. That has changed in recent years as manufacturers seek to keep costs down and cathode chemistries can be 5-3-2, 6-2-2, or 8-1-1.
Faraday’s ReLib project approach is to mix recycled materials with virgin materials to achieve the required ratios of nickel, manganese and cobalt.