Yeah, In "Joules" mode there isn't anything to indicate the charge level of the battery. If you shifted back over to Power mode, it would tell you.
That is a bit of an annoyance. It would be nice if it showed the battery level at all times. Personally, I could do without the "Joules" meter in the bottom left of the display. That seems about as gimmicky as a puff counter. Not really sure of it's usefulness other than to loosely determine how much you're getting out of a battery charge...
Are you saying there is no battery voltage indication at all in temp mode, what about the battery bar graph, is it gone?
The joules counter in the bottom left is not really needed IMO but it sure seems a great way to compare the health of your batteries, if you drain each one to the same voltage, it'll tell you if any are weak. Great for brand A/brand B comparisons too I would think. Could be wrong since I don't own one...yet.