Researchers are recycling old Nissan Leaf batteries using… bacteria?

Researchers at the University of Edinburgh in Scotland are investigating a way to recover the metallic content of EV batteries with bioengineered bacteria. The new method involves processing spent Nissan Leaf batteries into a “leachate” — a liquified battery slurry — and combining that slurry with said microbes.

The method isn’t described in a lot of detail, admittedly. Other than saying the bacteria used was selected and specifically engineered for the process, which occurs inside a bioreactor, we don’t really know how all this works. What is described is that the bacteria excrete the metallic content of the battery leachate as silt (read: the bacteria poop metal particles), which can then be isolated for use in whatever application it may be needed. Allegedly, this bioprocess yields silts of cobalt, manganese, nickel, and lithium.

The goal of the research at the Industrial Biotechnology Innovation Center is to scale up to a level that could conceivably be used to process a large number of batteries — though the question of cost scalability isn’t commented on (nor does that tend to be the main concern at this stage). Regardless, it’s fascinating research, and goes to show we’re probably still at the tip of the iceberg when it comes to creating a sustainable EV supply chain.

The use of bioengineering to break down materials isn’t a new concept — there’s similar research exploring bacteria to tackle the issue of microplastics and PFAS (non-degradable synthetics), though it’s all still in the very early stages. Now, it seems you can add batteries to that list.

For more, check out this article at The Institution of Mechanical Engineers.

Electrek’s take

Are bacteria the future of battery recycling? I mean, who really knows, but it goes to show the number of avenues we have left to explore. Unlike pulling carbon molecules belched from exhaust pipes and power plants back out of thin air, recycling batteries seems thoroughly feasible. And, eventually, it may even be cost-advantageous.

Recycling of EV batteries, in general, is a huge issue — Toyota recently signed a deal with Redwood Materials to commit to a more circular battery lifecycle. And given that there’s physically almost nothing lost when a battery is “used up,” creating this circular battery ecosystem should be a huge priority.

While advanced lithium extraction techniques are making the process less dirty, the cleanest raw material for your EV battery is one you didn’t have to pull out of the ground in the first place.