What kind of batteries?
Do the LEDs stay on on the Wiimote?
I have the factory batteries in one Wiimote since about Christmas and the batteries still show three bars. (Doesn't get used much.) The ones we use more are filled with Energizer 2500mah NIMH batteries and they last days or weeks (used probably 10 hours/week.)
You should definitely see better.
If you're using rechargeables, are you sure they're recharging fully?
Have you tried other batteries?