My black battery is bust as well. Plug it in, 10 minutes later it says it's charged. Had to switch to my older, whiter battery.
Spose I need a play and charge thing for that?
When the controller is off (with a battery pack in) 3 of the lights are still sort of faintly lit, is supposed to happen?

Yours are dead. Mine did this, (faint lights) just before it died. It lasted 2.5 years, so I just assume they lost their charge tbh.
The next stage after this is that they only work when plugged in with the recharge cable.
rp2000
My quick charge kit was pretty poor too. Was fine whilst it was charging but when it was sat idle it used to make a whistling sound making me have to pull the power lead out. Got rid of that pretty quickly, glad I didn't pay much for it.I bought the duel charge kit and and extra battery. Very first charge and it fried the 2 batteries leaving black marks on them.. I lol'd