I keep seeing posts about how much mining is needed for an EV battery, and that got me thinking.
Looking at the batteries I’m developing for our projects here means I can see exactly what goes into a full battery pack, I also have to deal with recycling cells that I have tested to destruction whilst checking they deliver what the manufacturer says they do.
I’m not going into how much resources are used in making the cells, maybe I’ll do a post about that some other time, but I wanted to see what happens to the stuff I send of for recycling and what that means for the environmental impact over a long time.
Firstly there’s a couple of things to get straight, batteries in EV’s last a long time, usually longer than the rest of the car. I drive a 2012 Nissan Leaf which is still going strong, we also have a 2012 Peugeot Ion which is at over 90% it’s original capacity.
The current crop of cars are experiencing battery capacity loss of less than 5% per 100k miles, so million mile EVs seem quite likely.
In the UK petrol and diesel cars last an average of 17 years, their life ending when crashed or uneconomic to repair, so it seems likely EV’s have the capability to exceed this.
Oh, and by the way, batteries are repairable contrary to popular belief. If you want to learn how to do this for a living I run IMI industry recognised short courses to show you how.
So batteries last a long time, and even if the car gets scrapped off the battery can be used in energy storage systems on your house or on the grid. This helps the grid out at peak times and also means we get much better use out of solar and wind power as the power can be stored and used when needed. Think about how many kWh you use at home each month, look on your electricity bill, many car batteries can store about 50kWh so if there was a power cut how long would that run your house? Couple that with solar on the roof and you’ve got a bit of energy independence.
But eventually everything ends up as scrap, in the case of our scrap batteries we use a place in Milton Keynes and I had a chat with them about what happens to our cells at their facility, which was really interesting.
One interesting point is that most cells have some energy left in them when going for scrap, so these guys use that remaining energy to power their factory! That also results in a cell with no energy at all, so no chance of sparking a fire as it goes through the plant.
The cells are then broken up and the component elements separated, aluminium, copper, nickel, manganese cobalt etc. are refined and sent for re-use. What’s left is a mix of lithium and graphite which looks like slightly damp mashed up pencil lead. This goes to another company for separating into graphite and lithium.
All these components are valuable to a greater or lesser extent, currently there are so few EV batteries coming out of service (they are still in use!) that the operation is relatively small scale which means I have to pay a small fee to get my ex-test battery cells recycled, but as volumes increase they expect to be able to pay me for the scrap cells in a few years time.
There are new battery recycling plants popping up now in the UK so it’s an industry that is growing.
This also means that the batteries I used and abused will be turned into new batteries.
Now here’s an interesting thing, battery manufacturing methods and designs are constantly improving, one of the type of cells I’m buying now are 15% better in energy storage capacity than the ones I bought last year. That’s an amazing change.
So the stuff I send for recycling gets made into batteries that are better than the ones they used to be.
It’s reckoned by people much cleverer than me that each recycling round results in improved battery efficiency by about 5%.
It also means that less and less mining is needed as the years go by, as more and more of the batteries are made from pure materials from recycled batteries.
There’s obviously some waste in the process but it looks like its about %5 of the mass, this is things like glue, stickers, some resins that don’t separate well, that sort of thing.
So even if the average battery life was only 10 years that would mean 50% of today’s mined materials would still be in batteries in 100 years time, and if they live as long as combustion cars that turns into 170 years.
Which I thought was interesting .
It’s also wrong. Because in 100 years we are unlikely to be still using lithium batteries. Look how far we’ve come in 30 years, from lead acid, to nickel metal hydride and now to lithium. So whats’ next? Sodium ion certainly, then maybe aluminium air (probably 10 times lighter, cheaper and smaller). Who knows.
But in terms of the current rapid expansion in the number of lithium based EV’s there is clearly a lot of mining to be done, this this won’t go on for ever, once we have enough for the growing fleet we can use a high percentage of recycled material. And a lot of that new material can be mined a lot closer to home, such as Cornish Lithium which is using the old tin mines. Maybe shipping huge quantities of material around the world isn’t really necessary after all? A lot of things are changing, and changing fast.