Scalable Battery Packs
Battery packs, to keep them safe, should be the 48V human electrocution voltage.
It is useful to scale battery power by increasing current. For example - we can create a welder from cordless drill battery packs if we stack a few of them.
A welder from 22V cordless drill batteries, with 6 of 2A 18650 cells - can produce up to 20A for 6 minutes. This means that 10 of these yields a 200A welder for 6 minutes.