So, are you saying that you've got the battery screwed into a USB charger dongle, then you had that plugged into a wall adaptor, and the LED on the end of the Volt battery never went out?
Is the USB dongle and/or the wall adaptor a SmokelessImage Volt brand or are both from other vendors? I'm asking because I don't know for certain if every USB dongle works with a Volt battery and I know for sure that the Ego wall adaptor does NOT work with the Volt battery, at least the Ego wall adaptor I got with my Ego. So which wall adaptor are you using? If the USB dongle is not a Volt, what was it used for before?
Like said before, when put on a charger, the LED of the Volt battery will come on. When it's done charging, that LED goes off.
And yes, anytime you remove charging power from a Volt battery, the Volt battery's LED will flash 3 times. That's normal.