Is it alright to keep the battery in the battery compartment even if it's fully charged or I have to remove it when using AC power?

It's time for you to replace your battery.

how old is your laptop? and how do u use it - do u leave it plugged into the wall socket all the time? It's common for batteries to die out after a couple of years. however, if the computer overheats or if you leave it plugged in all the time, it's life cycle will decrease. Charge - discharge cycles. That's how you are suposed to do it.

Is the battery fully charged? Has their been any damage to the AC jack due to pulling on the cord? If the battery is fully charged, remove the cord from AC outlet. Damage, from a power surge, and a battery malfunction, MAY/COULD result in a fire hazard.

If the battery appears to be charging, the drop in the time it sustains power is likely due to a faulty or old battery. Eventually it will appear 100% charged and drop to zero in 5 minutes or less. I would think you need to replace the battery.

If you want to maintain the battery properly, it is best to remove it once fully charged and use on ac power alone. If using the laptop on battery, remove the AC connection and allow the battery to fully discharge before recharging it ( there is some debate on this method, other may disagree)

RTFM You can download the manual by googling "acer travelmate 2480 manual" (without the quotes). Or just click here

According to the Acer manual:

"Conditioning a new battery pack
Before you use a battery pack for the first time, there is a
"conditioning" process that you should follow:
1 Insert the new battery without turning the computer on.
2 Connect the AC adapter and fully charge the battery.
3 Disconnect the AC adapter.
4 Turn on the computer and operate using battery power.
5 Fully deplete the battery until the battery-low warning appears.
6 Reconnect the AC adapter and fully charge the battery again.

Follow these steps again until the battery has been charged and
discharged three times.
Use this conditioning process for all new batteries, or if a battery hasn't
been used for a long time. If the computer is to be stored for more
than two weeks, you are advised to remove the battery pack from the
unit.

Warning: Do not expose battery packs to temperatures below 0°C
(32°F) or above 60°C (140°F). Extreme temperatures may adversely
affect the battery pack.

By following the battery conditioning process you condition your
battery to accept the maximum possible charge. Failure to follow this
procedure will prevent you from obtaining the maximum battery
charge, and will also shorten the effective lifespan of the battery.
In addition, the useful lifespan of the battery is adversely affected by
the following usage patterns:
• Using the computer on constant AC power with the battery
inserted. If you want to use constant AC power, you are advised to
remove the battery pack after it is fully charged.
• Not discharging and recharging the battery to its extremes, as
described above.
• Frequent use; the more you use the battery, the faster it will reach
the end of its effective life. A standard computer battery has a life
span of about 500 charges."

The first time you charge the battery allow 12 to 16 hours, after that 2 to 4 hours or when battery is charged. If you go on battery frequently drain it right down before charging it, this will give the maxi-um performance and longevity.

I had the same problem. This procedure from the "Technical Questions" section of http://shopdelphi.com/consumers/support/faqs/myfi/ worked for me:
"My MyFi won't power up, how do I reset it?
To reset your MyFi, start by turning the receiver off and removing it from its (car, home, audio system) cradle. Then remove the back cover and battery. Using a small paperclip, press the reset button located on the top left corner of the battery compartment. Now plug the AC power adapter into a wall outlet and plug the power port directly into the bottom of the MyFi (battery stays removed). Wait 10 seconds and listen for a beep. After you hear the beep the message "insert battery" will appear. Cycle the MyFi to ensure it powers up and powers down. If the power cycle is normal, then turn off the MyFi, unplug the power adapter, and reinstall the battery. Re-plug the AC power adapter directly into the bottom of the MyFi. Wait 10 seconds and listen for a beep. After the beep you will see the message "battery charging". Leave the MyFi plugged in until it's fully charged. You will see the message "charging complete" displayed. After the MyFi is fully charged, turn it on and reset to the factory defaults. Unplug the MyFi from the AC power adapter and using the battery power leave it on until it fully discharges (approximately 2-5 hours). Plug the MyFi in using the AC power adapter to recharge the unit and resume normal use. If you need help at any point during this process contact us at 1-877-463-3574 for technical support."

I hope it works for you too.

Clean the metal contacts on the Battery and in the compartment. Then, reset the BIOS to its default settings.
Next, plug in the AC Adaptor to charge the Battery.

If the issue persists then the problem may be related to the power circuitry.

Since, the Battery is not inserted in the Computer and it turns off automatically even with a slight movement when running on the AC Adaptor, it shows that the issue is with the DC-in jack on the Computer.

Now, to ensure if the issue is with the DC-in jack or internal power circuitry, it's required to diagnose the Computer after running it on the Battery power.

Remove the Battery pack from the Computer and clean the metal contacts on the battery and the compartment then, reinsert the Battery and check if it's charging. If not, try using a replacement battery.

If the Computer keeps turning off even if running on the battery power then the issue is with internal power circuitry.

Bye and take care.

I have a similar issue, it does not even power on even connected to ac adapter.

From Toshiba, try step-charging the battery or Battery conditioning procedures:

Batteries don't last forever. All types of batteries gradually lose their ability to hold an electrical charge as they age. Eventually, the computer's battery charge indicator may show that the battery contains less than a full charge, even though the battery has just been fully charged. The computer will then not run for as long a time from the battery as when the battery was brand new.
You may prefer to simply replace the battery if this happens, but you may also wish to try 'step-charging' the existing battery per the following instructions.
This procedure should work for the battery in any Toshiba notebook. Follow it only when you find that the computer will run from the battery for just a short while.
Check the User's Guide for more specific information about charging the battery in your computer .

Procedure

Step-charging the computer's battery

1. Unplug the AC adapter from the computer, and turn ithe computer on. Let the computer run from battery power until the computer turns off, indicating that the battery is fully discharged. Time this interval, but not with a software clock running on the same computer.
   
   
2. Remove the battery pack from the computer.
   
   
3. Unplug the AC adapter from the computer.
   
   
4. Wait at least 30 seconds. The first time through this procedure, use a soft cloth to wipe the battery pack's contacts and the AC adapter's plug.
   
   
5. Re-insert the battery pack.
   
   
6. Plug into the AC adapter into the computer again and check the fit of its plug in the wall outlet, making sure the connection is secure.
   
   
7. With the computer turned off, let the battery charge until the battery status light or icon glows green, or otherwise indicates a full charge.
   
   
8. Unplug the AC adapter from the computer.
   
   
9. Remove the battery.
   
   
10. Wait at least 30 seconds, then re-insert the battery.
    
    
11. Plug the AC adapter back into the computer.
    
    
12. Let the battery charge again until the battery status light turns green or otherwise indicates a full charge, again.

Repeat this procedure, starting from step 1, at least three times. Each time, check to see if the computer runs longer from its battery than the previous time.

Battery Conditioning:
IMPORTANT!! Interruptions in the charging cycle can be responsible for an issue called "memory effect" which may reduce the battery's charging capacity. Whenever you suspect the battery performance is not at it's optimum you should try using the following "Battery Conditioning" procedure.

Before you start: Turn off your battery saving features temporarily.

***IMPORTANT*** Repeat the following steps 2-3 times!

1. Unplug the power cord from the computer
2. Turn the computer on and let it run until it shuts itself off.
   Note: Using the CD-ROM to play an Audio CD will speed the discharge.
3. Plug in the power cord (While the system is off) charge the battery until the battery light changes from flashing green to solid green
4. Remove the battery for 30 seconds and then replace it.
   Note: If the battery light isn't lit, wait a few moments, if it still does not light check your power connections.
5. Continue charging the battery until the battery light turns solid green once again.
   **REPEAT THIS PROCEDURE 3 TIMES**
   

If I could be of further assistance, let me know. If this helps or solves the issue, please rate it.
Thanks, Joe


I’m happy to assist further over the phone at https://www.6ya.com/expert/joe_8b8c2cd6ce148309