The long read: What research is needed for the effective recycling of batteries?

What does battery recycling currently look like?

In Europe, batteries have been treated as e-waste, along with mobile phones and other electronics. Processes have not been optimized for batteries, but work for any kind of secondary scrap.

They have been good in recovery of base metals – nickel, cobalt and copper. But we have been losing a lot of valuable materials like lithium, aluminum, manganese, and graphite. Now because of increasing electrification, the game is totally changing. New policies will demand special operations for battery recycling, and there will be material targets, not only for the waste volume, but for recovery of cobalt, nickel, lithium, copper and so on.

Can existing processes that crush and shred the batteries still be practical with targets like these?

There are many different routes – one is to crush batteries and then put the remains into leaching. You can also crush and then smelt, you can put some types of battery directly into a smelter, or dismantle the batteries and use thermal heat treatment to remove some components, and then go to a hydrometallurgical treatment.

These have been quite successful, and there will be limits to what can be done economically and sustainably. However, innovations are needed to recover elements like lithium, manganese, graphite and the electrolyte materials, and also to develop more ‘direct’ recycling.

Lately, some battery manufacturers are moving away from nickel and cobalt chemistries to lithium-ferrous phosphate (LFP). Does this complicate things for recycling?

LFP batteries are much more challenging to recycle economically because they don’t contain the valuable metals like cobalt and nickel. There is no ‘treasure’ within an LFP battery. In Asia, where the manufacturers have been moving to LFP, there is more research into this. That is a true challenge, we think that NMC or NCO batteries are challenging, but they have valuable metals that are a big incentive for recyclers. One thing that speaks well for LFP is that it does contain lithium, and lithium is EU-critical. Regardless of price or impact, there is this question of raw material dependence, and that’s one motivation.

Is recovering lithium still challenging?

There has been a lot of focus on this recently, and a lot of new innovations. Five years ago, not much lithium was being recycled. Now, 70% or 75% will likely be a requirement in the EU’s upcoming battery directive. There are even some operators who have new innovations and are pushing for 90%. It is definitely possible; how economic and environmentally friendly … is something that still needs to be worked on and discussed.

Aalto University recently published work on a relithiation process to refurbish end-of-life cathodes, rather than stripping them down to raw materials. Where do things like this fit in?

There is a lot of research into processes like these, that we call ‘direct recycling’. There are different opinions, and it is not yet clear what the industrial limitations might be. In a laboratory it’s much easier to dismantle and try these processes. But at large scale, with thousands of tons of material, it’s much easier to throw it all into a furnace. Further research and innovations could result in a major decrease in processing and the economic and environmental footprint of recycling, at least for some applications.

How important is design for recycling? And do manufacturers still need to be convinced of this?

The topic is extremely important – not only design for recycling, but also for second use and for specific types of recycling – dismantling, chemical or metallurgical recycling.

I would say there is talk, but not much reality. And this needs to change – when we do research, we should look at raw materials, recycling, etc., from the start. Only very few researchers are really focused on this. I think it should be equally important as part of the economics, but it is not always the case. Recyclability and the environmental footprint of materials should be evaluated at the same time and give the same importance as performance. We don’t want to get too excited about something that could be much, much worse than the current situation.

Aalto University recently launched its BATCircle project, in collaboration with various industry players. Can you tell me a bit more about what the project is trying to achieve?

The project looks at the approach Finland could take at a national level, to be a hub for the processing of raw materials and recycling. What that means is also that we are very focused on the development of recycling and evaluating different recycling processes. We are not simply saying recycling is good, but looking to quantify and compare environmental and economic footprints of different recycling processes. And also encouraging companies and universities to publish their findings as well, to foster competition to reach the lowest environmental footprints or the best innovations. On the recycling side, we particularly want to look at how graphite and manganese behave, and whether they can be reused. We also want to study how best to recover lithium, and the environmental impacts of different processes.

Does the project also go beyond recycling?

The fact is, recycling alone will not be enough to cover raw material needs for a very long time. Primary production is still needed.

In the next 10 years, we will be able to get 10% maximum from recycled materials. It is truly important for Europe to also operate with primary raw materials. There is no way for electrification to happen without more mining. Finland has a crust that is very rich with raw materials, and our project will address making the most sustainable and efficient use of these.

We now have 16 companies and six research organizations on board. We study a wide value chain from mining to mineralogy, metallurgical refining, and the production of active materials up to the battery cells. It is highly technical and focused, but there is also this process simulation and evaluation of the environmental impacts that is considered alongside.