Collection and recycling of Li-ion batteries
Among all the challenges and opportunities related to Li-ion batteries, recycling is an important subject. In a world where resources are not unlimited and the amount of wastes grows bigger by the day, recycling can indeed bring positive change. Li-ion batteries exist in different shapes and composition; common components are copper, aluminium, graphite, lithium, nickel, cobalt… . All these different components can have at least a second life if they are recycled and they all have interesting economic value. As previously mentioned, those resources are not inexhaustible even if their extraction should still be possible in the near future. However, there are other reasons to avoid extracting these resources:
- The extraction and purification processes cost a lot of energy.
- The different processes are harmful to the environment; they release a consequent amount of CO2 and affect the local ground. In the case of Li-ion batteries, extracting the cathode and anode minerals accounts for most of the environmental impact .
- The materials are not evenly distributed around the planet which can be a source of tensions. Especially for cobalt whose reserves are already smaller than the rest of materials: half of the cobalt used in Li-ion batteries comes from the Democratic Republic of Congo, where its extraction causes armed conflicts, human right abuses and damage to the environment . Moreover, countries wishing to reduce their energy and resource foreign dependency should opt for more recycling in general.
In 2025, the demand for lithium alone could reach 80150 t/year according to the IRENA . In 2030, used lithium batteries could represent up to 2 million tons per year . Only extracting lithium and the other resources to match the demand would have a consequent impact on global warming and is contradictory to CO2 reduction objectives. If no recycling scheme is implemented, it will be hard to match the demand and to dispose all of the used batteries without contaminating the ground.
However today, if 99% of lead acid batteries are recycled in Japan and in Europe, most Li-ion batteries are not recycled . Li-ion batteries are very complicated to recycle because of different reasons related to both collecting and recycling phases. In many countries such as Japan, collection of Li-ion batteries is complicated because of logistic issues, regulatory gaps and not enough information being spread to raise awareness. Large-scale Li-ion batteries from electric cars or storage plants are able to be collected because they usually follow a different way than the domestic waste collection. Because the people who dispose this kind of batteries are not as numerous as the small Li-ion batteries users, organising the collection is easier among them. This is not the case for smaller Li-ion batteries. One big problem is that such Li-ion batteries exist in too different forms and there are no general rule as to which product uses them or not, so it has to be treated case by case when considering products for collection. Even if most mobile phones and computers use Li-ion batteries today, this is not the case of all electronic equipment in which Li-ion can be found as much as other types of batteries . In Japan, there is no law directly related to recycling batteries but the 2001 Law for the Promotion of Utilization of Recyclable Resources (link) requires manufacturers to handle the collection of small independent Li-ion batteries and organise the recycling process to recover the components. In other cases, the focus for collection and recycling is more on the type of equipment (computers, phones, cameras…) under the 2013 Act on Promotion of recycling of small waste electrical and electronic equipment (link) .
But this process is unclear for many consumers and manufacturers. A major source of problems is the question of removing the battery before the disposal. Because it is not always clear to consumers or manufacturers, batteries tend to be left in the product: up to 40% of Li-ion batteries could be incinerated or disposed with the product . When Li-ion batteries are removed, up to 1/3 of them still end with the other MSW (Municipal Solid Waste) and can either be incinerated or disposed. It seems that Li-ion batteries from mobile phones and laptops usually have a different treatment than other electronic equipment: because of better return policies and warranties, they are more often collected by the retailer, a recovery operator or sent to a shop to be reused if they are still working .
In the EU, the collection and recycling of batteries follows a different process because of 2 factors:
- The 2006 Battery directive (link) asks designer to ensure removal of batteries from the equipment and that it should be separated and recycled apart from the rest of the WEEE (Waste from Electrical and Electronic Equipment).
- There are targets to improve collection and recycling rates of batteries because even if the process is organised, it is not always effective: currently only 50% of the battery weight has to be recycled .
However, for both the EU and Japan, it seems to me that the real problem remains the lack of clear information. As long as the process is not widely recognized, collecting used Li-ion batteries will remain a complicated task.
As for the recycling process, the task is also complicated. Because the battery is not inert when it is disposed, disassembling manually is dangerous and requires qualified technicians which can be expensive. Automating the process could solve his issue but there are a lot of different Li-ion battery manufacturers and each of them follows a different model: there is no universal model for Li-ion batteries today so recycling has to be done case per case. Because Li-ion batteries were first designed to be efficient and energy dense, cathode, anode, electrolyte and separator already contain a lot of different materials bound physically together. In order to prevent overheating and fires from happening, some designers add sensors, circuitry and safety devices to monitor the battery activity which makes separating the components even more difficult. In order to do efficient recycling, separating and sorting components would be necessary but most of them have similar densities so processes like RedOx electromagnetic migration or solubility are required . Applying these processes to Li-ion batteries is very new and quite expensive however. Pyrometallurgy is a cheaper and practical option but it is not environmentally friendly and doesn’t enable to recover all the materials too: only cobalt, copper and nickel are usually recovered . According to C&En, less than 5% of Li-ion batteries were properly recycled in 2019, the rest would mostly go to pyrometallurgy as a backup solution . The hydrometallurgical recycling treatment seems to be a promising option to extract more materials. It is still expensive and complex but countries like China have already implemented it.
Overall, there are 3 main technical challenges in recycling Li-ion batteries:
- Deactivating the battery to make inert and safe.
- Separate the different components and extract the materials while preserving their grade quality.
- Make the whole process sustainable by limiting emissions of pollutants and energy consumption; avoid creating more wastes.
However, there are also economic challenges because of raw materials’ cost: if the price of minerals drops, manufacturers will prefer to use mined materials instead of recycled ones because of the cheaper price. There is an investment risk too: if new batteries like flow or solid state batteries become more interesting in the future, demand for recycling Li-ion will be reduced. The market is very new so its future is not very clear yet it can be very profitable. Some private firms like Li-Cycle, Fortum or NRCC have jumped on the current opportunities and came up with ingenious solutions to recycle Li-ion batteries.
If mined resources become more expensive, recycling will play an important role in the future to match the demand. Because Li-ion batteries were not designed considering the recycling phase, creating a new universal design for batteries would help a lot to recycle all components properly. Using less glue and weld for example would enable to separate all components more efficiently. If the process is complicated to standardize, then algorithms could be used in order to find the best way to approach dismantling. As the battery sectors grow bigger every year, there will be many more opportunities but one sure thing is that change is needed today to ensure sustainable growth.
-  Jacoby, M. (2019, July 14). It’s time to get serious about recycling lithium-ion batteries. C&En. https://cen.acs.org/materials/energy-storage/time-serious-recycling-lithium/97/i28
-  Md Mustafizur R., Abayomi O.O., Eskinder G., Amit K. (2020, November 1st). Assessment of energy storage technologies: A review. Energy Conversion and Management, Volume 223, 2020, 113295, ISSN 0196-8904, https://doi.org/10.1016/j.enconman.2020.113295 –https://www.sciencedirect.com/science/article/abs/pii/S0196890420308347
-  IRENA (2017, October). Electricity Storage and Renewables: costs and market to 2030. https://www.irena.org/-/media/Files/IRENA/Agency/Publication/2017/Oct/IRENA_Electricity_Storage_Costs_2017_Summary.pdf?la=en%26hash=2FDC44939920F8D2BA29CB762C607BC9E882D4E9
-  Asari, M. Sakai, S. (2013, October). Li-ion battery recycling and cobalt flow analysis in Japan. Resources, Conservation and Recycling, Volume 81, 2013, Pages 52-59, https://www.sciencedirect.com/science/article/abs/pii/S0921344913001924
-  Harper, G. Sommerville, R. Kendrick, E. Driscoll, L. Slater, P. Stolkin, R. Walton, A. Christensen, P. Heidrich, O. Lambert, S. Abbott, A. Ryder, K. Gaines, L. Anderson, P. (2019, November 6). Recycling lithium-ion batteries from electric vehicles. https://www.nature.com/articles/s41586-019-1682-5