Run it on battery on power saving mode until it has somewhere less than 40% left ... charge it back up and see what it says.

Laptop batteries will slowly lose the ability to hold a charge if you use the laptop as a desktop replacement and keep it plugged in all the time. If you use it as a desktop replacement, you should take the battery out or unplug the laptop periodically and let the battery drain down fairly low, then recharge it.

The clerk who sold my laptop to me told me to let the battery drain completely every once in awhile to extend the life of the battery.

Most things you read say use the battery up once a month and recharge back up.
Most newer laptops say leave the battery installed as they only charge when needed.

Some laptop / battery engineer I saw somewhere wrote.. if you're going to leave the battery out for storage, to drain it down somewhat and check it every now and then so not let it sit out at below 40% and also not let it sit out at anywhere near full charge for extended periods. He was talking about Li-Ions, which it seems almost everything uses now.

Vista learns how long battery life is... if you dont use the battery in a somewhat normal way, it will have not enough normal data, and will report non-normal run times.

Interesting....call me dumb, but I didn't know I could keep the battery out of my laptop and just use the power cord most times. DAH

Keep in mind if you have bad power or brown outs, or power blinks - that battery helps protect you from crashing or possibly even damaging some component on the motherboard.

Hi debi,
I was told that you should let the battery completely discharge through use from time to time.
Here's some information which says you should do exactly that - but ... I've also been told that that is not necessarily the case so it seems that opinions differ :

'Permanent capacity loss is greatest at elevated temperatures with the battery voltage maintained at 4.2V (fully charged). For maximum storage life, batteries should be stored with a 40 percent charge (3.6V) at 40°F (refrigerator). Perhaps one of the worst locations for a Li-ion battery is in a laptop computer when used daily on a desktop with the charger connected.

Laptops and portable devices typically run warm or even hot, raising the battery temperature, and the charger is maintaining the battery near 100 percent charge. Both of these conditions shorten battery life, which could be as short as 6 months to a year.

If possible, remove the battery and use the AC adapter for powering the laptop when the computer is used on a desktop. A properly cared for laptop battery can have a service life of two to four years, or more.'

This info was obtained through link below if you are interested.
Donna

Here is a link that might be useful: Battery Maintenance

Bought a MacBook last month. I keep it plugged in most of the time, but did recently let the battery drain down completely and then recharged. It's something I'll do once a month for maintenance sake.

Very confusing, I see I need to get my book out and read the battery maintenance again. Nothing is simple with electronics.

Thanks all. I do use the laptop as a desktop and keep it plugged in most of the time. And I let the battey drain a few times per week - down to where I only have several minutes of battery power left, then use the adaptor.

Yep...it is comfusing, Star.