6100 battery life question

Hi. Got a new 6100 and onto the 5th battery charge now. So far battery life
has been a bit disappointing. It last around 1-hr talktime + 80-hr standby
in generally . Is that normal?

A friend who bought a 6610i around the same time seems to be doing better.
So is the 6610i more efficient in battery usage?

Thanks.