From my research the Tesla batteries are irrecoverable if they are run too low.
FWIW I love off grid. My shop is powered but not my home. Once you get use to the winters it’s not too bad.
L-ion batteries last a long time if properly cared for. That means controlled discharge rate and controlled charge rate with temperature sensors.
BUT, they eventually fail, when they do they are extremely dangerous. I would NEVER EVER use one in my home. (I will never own a car with them.)
I’ve been a Ham operator for close to 50 years and hold a GROL commercial license. I am old enough to have had Elmers teaching me how to fix/build things.
For home off grid use, old fashioned golf cart batteries are a simple solution and they are safe and forgiving of discharge rate. With solar panels and a wind generator they are a simple solution to powering a cabin for most things. Air conditioning is not one of them.
I suspect that most wrecked battery powered autos have a serious disposal problem.