Replacing one solvent could speed up EU gigafactory deployment

My friend Jean Gravellier once drove me around the Dunkirk area. I’ve seen the ArcelorMittal steel plant, the nuclear power station, and locations for future battery gigafactories.

“Why there?” I thought. So many polluting industries, all in one place? There are many reasons, but one is permitting - businesses with a higher environmental footprint go where it is easier to get approval from local governments. There is a reason that many battery companies in Europe are in Hungary.

There is one particular solvent used in making lithium-ion batteries that requires tens of millions of euros in capital expenditure, several million euros in operating costs, and many months or years to navigate permitting procedures. This is NMP (N-Methyl-2-pyrrolidone). It is used to bind together various components of the cathode, creating a slurry, and after pasting a cathode slurry on aluminium foil, you need to dry it and safely divert NMP.

The drying process is one of the two most energy-intensive stages in lithium-ion battery manufacturing. It is also hazardous to human health, so extreme caution is required. All gigafactories have dedicated systems for handling NMP - dedicated ventilation systems, solvent recovery units, wastewater treatment, additional permitting, and a permanent HSE burden.

NMP demonstrates that discussions about battery competitiveness, like LFP versus NMC, are incomplete. Some of the most consequential cost drivers sit much earlier in the process, in places that rarely make it into public announcements or pitch decks. Removing NMP from the equation would make battery making process much less toxic and eliminate tens of millions of euros in capital and operating costs, and speed up the roll-out of EU gigafactories.

But that’s not all. In the next post, I’ll look at why this solvent question becomes even more problematic once you factor in localisation and Europe’s dependence on imported battery chemicals.