Electric vehicles are becoming more common on Scotland’s roads, but the power that powers them has left an environmental headache.
Efforts are now underway to explore how engineered bacteria could be used to recover critical metals from electric vehicle batteries, in what would be a major advance in bio-based recycling.
Sustainable biotechnology experts at the University of Edinburgh are exploring the concept of using bacteria to extract metal compounds from lithium-ion batteries.
Once recovered and processed, valuable elements such as cobalt, manganese, nickel and lithium could feed a new UK-based supply chain to produce more rechargeable vehicle batteries.
Similar microorganisms are used in the mining industry to extract valuable metals from ores. And bacteria have been used to recover e-waste materials such as printed circuit boards, solar panels, and contaminated water.
However, identifying the right bacteria to effectively tackle lithium-ion batteries and applying the process to what will eventually become a glut of waste EV batteries would solve one of the main problems related to the shift towards green automotive. .
It could also potentially be very lucrative: As the first wave of electric vehicle batteries begin to reach the end of their estimated 10-year useful life, the race is on among technology companies to find effective ways to recycle them.
Second-life EV batteries can be used for stationary energy storage in offices and commercial settings (although home use has raised safety concerns), but finding a way to extract rare metals and reuse them is considered a much better option. , as it helps avoid further extraction and diversion of old batteries from landfills.
In Chile, where large quantities of the world’s lithium lie beneath the Atacama Desert, the water-intensive lithium extraction process has put pressure on local people and ecosystems, and has been blamed for causing drought in the natural waterways, affecting communities and wildlife.
While the nickel present in two-thirds of electric vehicle batteries is extracted from the rainforests of Indonesia, which also raises environmental problems there.
The Industrial Biotechnology Innovation Center (IBioIC) is supporting the University of Edinburgh’s project to achieve industrial capacity using its FlexBio center facilities to refine the process in a larger bioreactor.
Meanwhile, bacteria have been selected and engineered using the Edinburgh Genome Foundry, based at the University of Edinburgh, to ensure their effectiveness at scale.
Using a fermenter, bacteria are added to the battery leachate (the liquid left after the initial processing stages) to simulate a natural biological reaction.
During the process, bacteria produce nanoparticles of metal compounds, resulting in a sediment that can be separated and filtered from the residual liquid.
Tests are being carried out on material recovered from an electric vehicle battery previously used in a Nissan Leaf.
Professor Louise Horsfall leads the research team at the University of Edinburgh. (Image: Contributed)
The latest research forms part of the wider Reuse and Recycling of Lithium-Ion Batteries (ReLiB) initiative, led by the University of Birmingham and funded by the Faraday Institution, the UK’s independent institute for the science of energy storage. electrochemistry, skills development and market analysis. and early stage commercialization.
According to the European Automobile Manufacturers Association (ACEA), battery electric vehicles accounted for 16.1% of total new cars between January and June 2023, making the UK one of the top ten European countries in electric vehicle sales.
While the UK Government has confirmed that 80% of new vehicle sales by 2030 must be fully electric, or another alternative, and carmakers face high charges for every petrol or diesel engine above that threshold.
The growing market and dwindling reserves of metals used in batteries are likely to fuel a race to find new ways to deal with discarded batteries as they reach the end of their useful lives.
While most metals used in electric vehicle batteries are currently imported, the development of alternative recycling routes could open up a more sustainable materials pipeline based in the UK.
Professor Louise Horsfall, chair of sustainable biotechnology at the University of Edinburgh, who is leading the research, said: “We often read about initiatives to reduce the costs of electric vehicle batteries and improve their performance, but as the green transportation market grows, we must also consider what happens to the technology once it is no longer fit for purpose. use.
“This project is about using cutting-edge sustainable biotechnology to find ways to address that challenge and, in turn, extract some of the most valuable metals that can be returned to the sector in the early stages of vehicle production.
“The work of the Edinburgh Genome Foundry to select the best performing bacteria, combined with the scale-up expertise we have been able to access through IBioIC, means we are heading in a positive direction to turn the idea of research into an industrial reality.” . “
IBioIC was set up in 2014 to stimulate the growth of industrial biotechnology (IB) in Scotland. It is a key driver of Scotland’s National Industrial Biotechnology Plan, which recently set a new target of £1.2 billion in associated turnover and 4,000 direct employees by 2025 for the industry in Scotland.
Dr Liz Fletcher, head of business engagement at IBioIC, said: “This project is a great example of how biotechnology can be used to make everyday products and services such as cars and transport more sustainable.
“No one wants lithium-ion batteries to end up in landfills, so it’s important to explore different ways to reuse and recycle them.
“The method being developed here has dual value: in addition to being a petrochemical-free way of treating waste, it could also help ‘reshoring’ the supply chain for rare metals and future battery manufacturing.”