Yes, 7.4 is correct. I was working while I replied last time and 7.2 was a typo. It's an old holdover from when Li-ion cells used to be regarded as 3.6V. It's one of those grey areas. If you ever take a voltmeter to a brand new, fully charged cell, it will read in the neighborhood of 4.2V. It's one of those things I guess.