Tips to Extend PDA Battery :

1. Make sure to use the AC adapter. Make sure you connect your PDA to the AC adapter (or put it in the cradle) whenever you are close to a power outlet. This will not only recharge the battery, but also help extend its life.
2. Always power down when you are not use your PDA. You have the option of setting your device to turn off automatically after a specific period of time, if you do not use it. The time can vary from 1 to 5 minutes - or more, depending on your brand. On most PDA's, you can adjust this setting by going to "On battery power".
3. Adjust LCD brightness as you need, not so bright. A very bright screen consumes a lot of power and it is probably more than you need. In most cases, you won't even notice the difference if you adjust the brightness down a little bit. This will work wonders on your battery though, it won't have to work so hard, therefore it will last longer! You can adjust this by going to Start>Settings>System>Backlight>Brightness. Adjust the bar named "On Battery".
4. Set backlight time as you need. As with powering it down, you have the option to have the backlighting turn off automatically after a certain period of time (if you don't use it). You can have a lapse time of 10 seconds up to 5 minutes. Go to Start>Settings>System>Backlight>Battery Power. Check the box labeled "Turn off backlight." and select your time.
5. Becareful of using memory card. Get rid of them when you don't use them! If you are not using PC and CF cards, remove them from your system. This includes file storage cards and I/O cards like modems and wireless LAN cards. Moral of the story: set your PDA on the lowest settings (or the lowest that is comfortable for you). Remove any unused devices, as they consume power that could be used otherwise.
6. Do not overclock the PDA. Some of PDA user do this to make the faster speed usually with software tweak and sometimes with hardware. This will drain the battery faster and may even void your warranty if you open the circuit.

This is 5 signs that Your PDA Battery Might Be Dying:

1. Your use time on a full charge decreased. (for example from 4-5 hours, now you get 1-2 hours).
2. After a full night charge, your PDA will not come up at all.
3. When you press the power, you just get some vertical lines.
4. Your picture dims.
5. You had your PDA for over a year.