I want backpack battery packs for the bigger power users. Chainsaws and weed whackers and stuff in the gas engine range anyway. For smaller tools there could sensibly be a couple to 4? perhaps sizes of battery pack, "handheld" for screwdriver to toothbrush to "personal manipulation tools", a bit bigger for handheld drills; double that again for small saws and stuff... any bigger and it begins to become an an unwieldy…
It'd be crazy expensive
We have a Dyson vacuum running with like 12 molicell p42a’s in it & it’s insane. Can suck on max setting for like 20 minutes, & even then motor overheating is a larger issue than running out of battery.
Kweld & maletrics spot welders have turned making a custom Li-Ion/else pack into child’s play for the average person who’s turned a screwdriver in their life. Those two are a bit expensive, but older & clunkier spot welders can be found for extremely cheap at this point. They’re more than enough for making power tool packs for you & friends.