[oppositelock]

There are companies attempting to recycle them into new batteries, such as Redwood Materials, but from what I know, recycled lithium is more expensive than fresh lithium today.

The problem with used EV batteries is that they've started to degrade, and they degrade in chaotic ways, so you can't offer a predictable product made from old cells. Some cells may have shorts internally, others may have evaporated some electrolyte, or the electrodes may have degraded. Right now, lithium recovery is quite primitive from used cells. I've tried to reuse used batteries myself for storage, and the unpredictable wear made me give up.

Also, EV batteries, which are optimized for power density, may not be the best choice for home storage, where you want the ability to deep cycle to buffer power usage as the NYT article describes. The NMC cells common in EV's don't like to sit at above 90% state of charge (this cutoff is arbitrary, but > 90% results in fast breakdown), and they don't like to go below 20%, so you have a useful range of 70% of the capacity. You can over-provision by 30% or you can use lithium-iron-phosphate cells, which are less power dense, but much more tolerant of deep cycling.

I set my home up like this a long time ago. I use 100% of my solar and export nothing to the CA grid due to batteries. It's not cost effective to do this given the cost of storage when I set this up, but it's really neat to someone of my nerdy predisposition. My goals originally were to have solar based backup power, because I lose power quite a lot despite living in silicon valley, and it's worked great for that too.