Low battery indicator problem

I have a 20" iMac which is not even a year old. Yesterday, the low battery indicator started to flash so of course, I changed the batterys with new duracell's. Same problem. I constantly flashes with known good batteries (I tried various sets of known good ones). I clicked on the battery icon, and tried to rediscover my mouse but it couldn't be found after many tries. Help!!!! What can I try???? Your help is appreciated. Oh yes, the mouse works perfectly, but the blinking battery icon bugs me. Thanks

Try going to

System Preferences >Keyboard & mouse

it will show what it sees for battery strength. Try turning off mouse ....wait 5 seconds then turn on. It will reestablish a connection and in case it does not the same control panel use Set up device. BT devises are tricky items.

As it turned out, it wasn't the battys in the mouse that was the problem, but the keyboard battys. Replaced them and now no problem. Thanks for the help.
Stemo