COVER STORY: THE TROUBLE WITH LITHIUM — RECYCLING Closed loop
For a truly closed-loop in lithium battery recycling, as much material value and structure must be retained. The technology that looks closest to a true closed loop is direct recycling, says Harper, where value is created rather than destroyed. However, there are questions. “For direct recycling, there remain substantial technical challenges in being able to disassemble batteries cost effectively — furthermore, there are also some social-business model questions that this approach would raise. “For example, if a recycling plant processes batteries from a range of different manufacturers, how might one manufacturer feel about making and warranting a ‘recycled’ battery that contains the recycled cathode material from another manufacturer? Surely there would need to be robust processes to ensure quality control and prevent contamination. “Where there is a more immediate opportunity to close the loop is in the short-loop recycling of production scrap and quality control fail cells. No process is perfect and manufacturing batteries results in production scrap. Because this could potentially be of known provenance, there is an opportunity to get closed loop processes right with scrap material within the manufacturing process.”
Removing disincentives
Lead acid battery construction and composition contribute to its ease and economy of recycling. lithium batteries require a more complex recycling process to recover the value from them. The value of lead acid batteries is also an incentive for collection. “If we can optimize the economics of LiB recycling, then we can ensure there are no disincentives to recycling, says Harper. Vasant Kumar has been working on lead acid battery recycling at the University of Cambridge and has developed a hydrometallurgical process, which enables regeneration and upcycling of end-of-life lead acid battery paste. He is sceptical about the chances of lithium battery recycling catching up. “The lithium battery supply chain is not as established when it comes to recycling. Battery chemistries are not harmonized, meaning that several different chemistries exist and are being developed — so a single process that can manage all lithium batteries from
52 • Batteries International • Autumn 2020
“We are recovering cathode material, which retains its value even as there is less and less value in the constituent elements. Other recycling technologies rely on cobalt content for profitability” — Linda Gaines, Argonne National Laboratory
a recycling point of view is not a realistic concept. “Moreover, lithium batteries possess several important elements, including lithium itself, that are not currently recycled, whereas lead can be recycled from end-of-life lead acid batteries with minimal loss.” Spiers is more optimistic: “Remember that lead acid had a very long time to get this far. With lithium-ion we are only just starting. So, I am confi-
dent that we will get there.” ‘Design for recycling’ may be the best way forward. This is where the batteries and packs are constructed to make them relatively easy to pull apart and to be recycled at the end of life, so reducing time and cost. However, the market is not communicating to manufacturers to do that now because it is too early. This may be an area where some regulation is likely and could be useful, says Goodridge.
“Lithium battery chemistries are not harmonized, meaning that several different chemistries exist and are being developed —a single process that can manage all lithium batteries from a recycling point of view is not a realistic concept” — Vasant Kumar, Cambridge University www.batteriesinternational.com