Recycling Lithium Can Help Stave Off Shortages

­Our reliance on lithium is growing at an unprecedented rate. Although other battery chemistries are getting closer to commercialisation, there’s unlikely to be one available in the immediate future that could replace lithium-based batteries in large scale applications. That means that the demand for lithium will continue to increase as electric vehicles replace ICE vehicles and more consumers buy domestic storage for renewable energy and purchase battery powered consumer goods.

There are currently initiatives around the world to mine more lithium, but that is an environmentally unfriendly business and it can take years before new mines come online. In the meantime, the first generation of electric vehicles have batteries that are coming to end of life. We also dispose of a multitude of phones, tablets and other electronic goods each year. If those batteries could be reclaimed and recycled, it would ease some of the pressure on the supply chain. There are many companies exploring that possibility at the moment, but the processes can be environmentally unfriendly, expensive or use so much energy in the reclamation process that it is commercially unviable. However, that could be about to change, as the Karlsruhe Institute of Technology (KIT) has developed a new method of reclaiming up to 70% of the lithium from battery without using corrosive chemicals, high temperatures or time-consuming material sorting before the recycling process. At the moment, nickel and cobalt, copper, aluminium and steel are the main elements recovered from battery waste for reuse, as recovering lithium tends to be so expensive that it is hardly profitable.

The new recycling method combines mechanical processes with chemical reactions, enabling cheap, energy-efficient, and environmentally friendly recycling of any type of lithium-ion batteries. The mechanochemical approach is based on using mechanical processes to induce chemical reactions for a higher yield, while being both more environmentally friendly and cheaper. The method was developed by the Energy Storage Systems Department of KIT’s Institute for Applied Materials (IAM-ESS), the Helmholtz Institute Ulm for Electrochemical Energy Storage (HIU), and EnBW Energie Baden-Württemberg AG. The results are reported in Nature Communications Chemistry (DOI: 10.1038/s42004-023-00844-2).

The technique uses the aluminium found in the battery’s cathode as a reducing agent in the mechanochemical reaction. Initially, the battery waste is ground. The resultant material then reacts with aluminium to metallic composites with water-soluble lithium compounds. Lithium is recovered by dissolving these compounds in water and evaporating the water through heating. As the mechanochemical reaction takes place at ambient temperature and pressure, the method is energy-efficient. The simplicity of the process also means that it should be easy to scale to an industrial level.

Initiatives like this are needed if we are to complete the electrical transformation process as soon as possible. The circular economy looks to be taking off quickly, which is good for society. If the reclamation process is cheap enough, then paying consumers for old batteries may even be possible to sustain the supply.