Anyone ever seen these before?
 

So I was looking for some different battery packs for my Associated 18T and I came across this thing. Anyone ever seen anything like this before?
Would that work for an E-Maxx as well (obviously with larger cell to match.)
Thanks.

it will work but you just have to make sure your charger can charge low cell counts. my millinium can only charge 4 cells minimum

Wouldn't you just charge it at the same time with the others while it's plugged into them?
Thanks.

The problem with doing that is that 1 cell will be different from the others. Aswell as more resistance.

Better to just solder the cell directly onto your pack.