So, did we ever figure out where one could buy a 5v bat (mod) for KR808D-1 carts?
I just ordered Notcig's Buzz mod. Got the 901 connector which is 808 compatable as I understand it. All of my cartos are V4L 808's, both cool carts and the WOW carts. It's a pipe bomb sort of battery, adjustable voltage. Very sturdy, almost unbreakable design. Not a sleek looking mod, but something I will use out in a pub sort of thing.
NotCig also has another sleeker looking mod just introduced, the Infinity. Down the road I may buy one, I want to see more feedback on it first. That is 808 compatable too.
You can always buy an adapter from just about any connector to an 808 compatable, and they are pretty small. All the mods are bigger than single KR808's are. They keep getting smaller though.