US $1,258.00 26%OFF | GTK Waterproof li ion 12V 800AH lithium ion battery with BMS for golf cart backup power Solar energy storage MPPT + 20A Charger
https://a.aliexpress.com/ _mPqiuLE
Do not buy this unless your name is "Will Prowse" and you want to test this battery on your YouTube...
I started off saying do not purchase unless you are a reviewer on YouTube.
There are lots more of these, and 48vdc at 200ah.. I picked this one because the bad review that if you read it, it doesn't even make sense.
The more I think about it I have to make a custom battery anyways.