Pete Gruber of Gruber Motor Company (the first commercial independent Tesla service organization providing engineering and aftermarket support) and Sandy Munro, the “Tear Down Titan”, (an automotive engineer who specializes in machine tools and manufacturing); had a conversation on Gruber Motors YouTube channel regarding the 4680 Tesla battery and the pink foam.

The pink foam / potting material covers the entire battery pack and  keeps a barrier between the 4 modules and acts to lessen thermal runaway. 

On Munro Live YouTube channel, Sandy reported “4680 Battery Pack: WHAT WE FOUND UNDER THE FOAM!” that the battery pack can be immersed in a vat of liquid nitrogen to dissolve the foam and the rest will be pulverized to extract pure ingredients including high-quality Ore. It will be floated and different densities will separate and sort the elements.  Everything that is in there can be recycled as if new.  

That is great news for battery recycling, except for the fact that they said that JB Straubel of Redwood Materials was going hungry because the batteries are lasting and there aren’t enough to be recycled. 

What happens when a module or cell needs to be replaced and can’t be identified or modified due to the “pink foam” material?

And is it possible to repair and/or isolate 1 cell? 

It’s possible to use the dry ice and an air compressor to remove and check and perhaps locate the bad cell. Pete even mentioned possible x-ray and drilling into the pink foam to get to a potentially bad bonding wire- like orthoscopic surgery.  You would need to find what you need and don’t touch the rest if you choose to go this route.

Likely, what could need fixing IS accessible, for example:

Battery Control Module  

Connectors to & from battery

Check out Recurrent: According to their research:

“Our team studied roughly 15,000 EV batteries in the Recurrent community and found several interesting things.

• Battery replacements are quite rare. Only 1.5% have registered a new battery (outside of publicized recalls like Chevy Bolt).
• Range loss is not linear. There’s some drop in the beginning, then it levels out for a long period. 
• Most replacements occur under warranty. These are typically the result of an issue with an individual pack, rather than premature aging or regular wear and tear”.

2 Things Unrelated To EVs…

1. Pete Gruber’s voice is so calming & peaceful. He’s like the Bob Ross of Roadsters
2. I love Sandy even more.  

(Sandy, I never went to a prom either)

There is so much more here:

Gruber Motor Company Youtube: https://www.youtube.com/watch?v=pcckH3-IVwg&t=1731s

Munro Live Youtube: https://www.youtube.com/watch?v=ozesI3OZEG0

Recurrent Info: https://www.recurrentauto.com/research/how-long-do-ev-batteries-last