The Obstacle Course on the Path to Repurposing Used Electric Vehicle Batteries (EVB). Part I: EVBs aren’t designed to be taken apart!
Part I: EVBs aren’t designed to be taken apart!
As you may know, we secured a $3M grant from the California Energy Commission (CEC) to repurpose used electric vehicle batteries into a solar plus storage application. At the outset of the project, we knew there were going to be challenges. In fact, we even highlighted four of them and how we would tackle each one over the course of this 3 year project.
Steven presented our solution to the challenge of long testing times during our project kick-off meeting
When we got our first samples of used batteries, we quickly learned of a few new challenges.
First a reminder: EVBs are huge and heavy. We got a sample from 3 trucks where each truck had 3 packs and each pack had 20 modules - so we have a total of 180 modules. Each module is 45 lbs, so each pack is about 1,000 lbs! You cannot move this without the right equipment.
Now to our challenges which we’ll summarize in the 3 D’s
it’s Dirty. It makes sense because batteries are normally under a car, all the dirt and grime from driving around will build up over time. The amount was so overwhelming we could not easily work without dust getting everywhere so we had to sweep off as much as we could outside. Remember, hosing it down is not an option here!! 🙅🏻♀️
After we’ve cleaned it reasonably well, our next challenge: Damage. To remove the cover and access the batteries, there were about 20 screws we had to remove. Seems simple right? Well, these battery packs have undergone real-world driving conditions. A benign bump on the road can bend a screw out of place just enough to make it impossible to ever unscrew which took us an extra 20 minutes and resulted in our first casualty.
The batteries are designed to stay together. This presents a major challenge at end-of-life whether you want to repurpose or recycle because we must test them and get some idea of the battery’s health and charge.
Dangerous. Last but not least, each pack is ~360 volts and almost 300 amp hours. Even if you don’t hurt yourself you certainly don’t want to damage the batteries you seek to repurpose. In short, you must be skilled to know where and how to be careful. This is NOT something your average technician or mechanic should trifle with. One of our electrical engineers figured out how the system is designed and created instructions on the safest way to disassemble. He even planned for eventualities - like leaving the pack on a pallet in the event there’s a leak from the sink on the 2nd floor and covering up exposed terminals in case something falls.
The reason we had to create our own guide was that we received little to no instructions. While these batteries weren’t that old - think about how long you keep your car. Is it 5 years? 10? If there was documentation, the person who created it may not even be at the company anymore let alone in the same role.
You may not encounter all these problems if you buy a used battery from a third party. But know that someone along the supply chain had to find a way to deal with it, which takes time and money. We’re committed to finding ways to remove these obstacles in the future which is why we’re sharing some of the challenges today.
Thank you for reading. I invite you to follow us on social media (links) to stay up to date on when we have new posts. We’d love to hear from you as well. Have you had challenges you experienced that we didn’t cover? Or do you have some great ideas on how to overcome some of the ones we discussed in this blog?
Cheers,
The ReJouligans