Simple battery pack question
Multiplying the amp hours by the voltage is does not give you Watt hours. This is because the voltage of the pack drops during discharge, meaning it's not a flat 3.7v over the whole 0.75Ah. To figure out the exact Watt hours the pack would need discharged while recording the current and voltage of the pack. The readings would then be integrated to give you the packs Watt hours.