I've had a Dell Axim x3i for about two years now, and recently, I thought the battery was reaching the end of its life. The battery meter would say 100%, but within an hour of use, it'd be giving me a warning about being low on power. Over the course of a weekend, with three or four missed reminders, the thing would often be dead by the time I brought it back to work to recharge on Monday. Beam receive was off, wireless internet was off, but still, no more than an hour of juice. One change I made was to prevent button presses from turning on the power (the wireless-ON button is an easy bump in a pocket), but it didn't seem to help.
I figured I'd have to get a new battery, but a posting on PDAStreet.com got me to thinking. I'd been tossing it on the charger on Friday afternoon, letting it charge for an hour or so, and pulling it off the charger on the way out the door. The meter said 100%, but what if the meter, for some reason, was wrong? So, two Thursdays ago, I left it on the charger all day, and continued all Friday morning. I left for a "camping" trip on Friday at noon, but by the time Monday rolled around, I still had 40%+ power.
I got myself back in the habit of placing it on the charger for a full day, and when I checked the meter this morning, after a weekend of occassional use, it was still at 65%.
So, before you go out and buy a new battery, try leaving it on the charger, even when the charger says it's at 100%, 'cause it's not really at 100% when it says it is.
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