Cambridge battery recycling technology set to disrupt global market
Car batteries will get sustainability built in
A new new method of recycling, improving and reusing battery paste has resulted in a Cambridge-based company being awarded a £465,000 grant from the Innovate UK-Newton Fund to develop the technology in Brazil’s urban environments.
In partnership with the University of Cambridge, Aurelius Technologies has introduced a patented hydrometallurgical process for the recycling of waste battery paste. The process is energy-efficient, non-polluting, low-cost and scalable. The firm’s Brazilian partner, Antares Reciclagem, secured £210,000 as part of the same bid.
Aurelius’ technology director Dr Athan Fox said: “The global lead-acid battery market is forecast to reach $84 billion by 2025. This is driven largely by expansion of the automotive industry in developing countries, including Brazil.
“More batteries on the road means an ever-increasing amount of battery waste, so our process for the recycling of lead-acid battery paste could not be more timely. The Innovate UK-Newton Fund is allowing academia and industry to join forces, taking Brazil and the UK a step closer to clean, economic and sustainable recycling of lead-acid battery waste.”
Electrochemical processes take place in the engine room of the battery, where the paste meets the electrolyte. At the start of its life the paste is made up primarily of lead oxide. At the end of the battery’s life it is no longer lead oxide, it’s lead sulphate. What happens to this paste – how it’s disposed of – and making a more efficient paste are some of the issues Aurelius’ technology is addressing.
The method is both eco-friendlier and performance-enhancing: creating the battery paste with Aurelius’ hydrometallurgical process reduces its carbon footprint by more than 80 per cent compared to treatment with the pyrometallurgical process – the incumbent method. The hydrometallurgical process developed by Aurelius also eliminates noxious gases such as sulphur dioxide and nitrogen dioxide without having to deploy gas abatement technologies.
Current lead acid battery recycling requires huge plants and massive scale to work cost effectively. This typically means that heavy, toxic scrap batteries must be transported sometimes hundreds of miles to be recycled, with all the costs and environmental impact of waste migration.
In some parts of the world, even in Europe, whole batteries – including their plastic casing and electrolyte – are burnt to recycle lead metal. Even if the plastic and electrolyte are separated and removed before the rest of the battery is tossed in the furnace, the lead sulphate paste is expensive, difficult and environmentally hazardous to convert to new lead oxide, which requires an intermediate stage – the production of a lead ingot.
The Aurelius approach is to convert waste battery paste directly to lead oxide, without producing or handling a lead ingot. This offers advantages over the incumbent industry, including reduction in the carbon footprint (by more than 80 per cent), zero-emissions of noxious gases, an improved lead oxide (with potentially up to 30 per cent higher energy density compared to lead oxide made from virgin ore), and lower energy demand for the recycling process.
Aurelius and the University of Cambridge have teamed up with Antares Reciclagem, specialists in the treatment of waste battery acid, and Tudor Batteries, a lead-acid battery manufacturer, both in Brazil, to pilot this holistic approach to lead-acid battery recycling. Antares brings to the table a process for cleaning the electrolyte and re-using it in other industries, including the pulp and paper industry.
Almir Trindade, chief executive officer at Antares, said: “By recycling the waste battery acid we completely avoid neutralisation, saving 85kg of carbon dioxide for every tonne of electrolyte treated. Our process is not only green, but also saves money. This is why about 80 per cent of Brazilian lead smelters now use our technology.”
Miles Freeman, chief executive officer at Aurelius, said: “There is a great opportunity to combine the technological achievements of Aurelius and Antares to deliver cleaner, more economic and sustainable recycling for lead-acid batteries.”
Indeed, electrolyte recycling and battery paste recycling go hand in hand – both waste products come from spent batteries.
Involvement in the trade is split into two functions, says Dr Fox, who previously worked at Cambridge Enterprise. One service, funnelled through Aurelius Environmental’s Tipton site, involves addressing the needs of legacy battery recycling. The other, based in Cambridge, is to develop new technology for the recycling of lead-acid and lithium-ion batteries.
“Today, we collect over 10,000 tonnes of lead-acid batteries from all over the UK,” explains Dr Fox. “We are forecast to grow throughout and beyond 2018. We open these batteries and separate the individual components – and we hand the lead metal, plastics and electrolyte products to recyclers in the UK and the EU. We make profit from this operation – in fact it’s our financial muscle, greasing the wheels of innovation.
“As for the paste – we are indeed converting it to lead oxide but at the moment this is all used up in trials and testing. We do not yet have a market for the lead oxide. The Innovate UK project will help us get closer to this by putting the oxide in batteries and demonstrating the commercial benefits of the increased energy density.”
Aurelius Technologies has now successfully raised more than £2million in funding – through two Innovate UK awards, a Horizon 2020 SME (Phase 2) Instrument and EPSRC funding. The core technology is patented in the US, China, Russia and India. Technology extensions and improvements are being patented in more territories including the EU.