I don't claim to be a battery expert, however, the owner of company that distributes a lot of batteres told me in person that the 2900 MAH AA is mostly a dream of the advertising department of the manufacturer to sell more units and that he didn't personally believe they provide that much capacity (Oh, he sells them of course but he doesn't beleive they are any better than the ones Uniden provides initially). BTW I purchasd my first HP-1 the day they were released to the public and have been using the original battereis daily since with no problem, but maybe I have just been lucky.