I tried the locking cover that came with the extended 2050 Mah battery with my Mugen 1800 Mah and it works ok but not all of the time. Sometimes it will not switch on. I am guessing that it is more a locking mechanism than a battery problem but I could be wrong. My standard battery and cover always works ok.
I am beginning to think that the locking mechanism design on the Axim is nothing more than a poorly thought out gimmick. There would be no need for such a locking device if they designed a decent battery cover in the first place.
EDIT: Update, I managed to get the extended battery working once by fiddling around with the latch but since this only happened once, I think it is a battery latch problem as opposed to the actual battery. The latch looks fine though.
EDIT2: Update, I managed to fix the problem after reading a battery latch fix thread in this forum from a few months ago (I must have missed it in my earlier searches). Applying thin black masking tape to the legs of the battery latch fixed the issue. Thanks to this site
