Red Wood Materials by former Tesla CTO is already reusing and recycling batteries at scale. Basically, they process all sorts of batteries. They've developed tools and electronics to monitor battery packs and cells. In their main facility in Nevada, they simply wire up the batteries and put them outside. They use solar power to charge the battery. The whole facility runs on that.

An interesting aspect with degraded EV batteries is that there's still plenty of life left in them. Also, they last longer if you limit their power output, charging speeds and cool them properly.

The batteries don't actually get recycled until they stop working. They have a few gwh of battery storage made out of repurposed EV batteries and a facility that processes expended cells to recover all sorts of materials. A lot of what they do boils down to inspecting and monitoring packs and cells and interfacing with existing battery management solutions.

Apparently, they are recovering a lot of material and selling it back to battery manufacturers already. Both the storage business and the material selling business have the potential to generate nice amounts of revenue.

The main limitation for growing the business isn't technical but the fact that there simply aren't that many batteries yet to recycle. It will be some years before supply of end of life EVs and batteries starts ramping up. And years more before their batteries stop being useful for storage. A lot of the batteries they process are discarded during the production process.