DIY 100 KWh PowerWall. https://hackaday.io/project/169134-diy-100-kwh-powerwall
I'm actually considering doing EXACTLY this. I already have a couple of old data center UPS rack units I picked up a while back.
So it's nice to know you can make it work!
(My plan is to provide power to only a few house circuits: office computers/lights/TV, kitchen appliances and fridge/freezers, pellet stove.)
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