The chemistry of the batteries is what determines the voltage. I very very seriously doubt those are 1.5 volt batteries.. Epically from the language you used to describe the capacity..
Also. 1100mWh is not ridiculous as you suggest. IF the batteries are, in fact, 1.5 volt that is 733 mAH.. Kind of like a trick Wal*mart uses on it's 12 volt automotive size batteries.. If you look at the labels at Wal*mart a group 24 is over 100 amp hours capacity AT THE ONE AMP RATE
At the C/20 rate that's 75 amp hours.
They used a non-standard method of rating the battery (A DIShonorable practice) in order to make them look better than they really are.
