...I really should leave the power supply connect to the main outlet all the time, with the fully charged battery installed....

(Yes, that's my first laptop I'm playing with here)

I'm pretty sure most laptops have fairly sophisticated battery charge management mechanisms that will prevent any possible damage that leaving the machine plugged in could cause. Someone will probably correct me if I'm wrong.

Yes, leave it connected!

Your laptop battery has a finite number of charge/discharge cycles, perhaps 500.  Disconnecting it and using it (perhaps only for 10-15 mins), then hooking it back up will actually use up one of your charge cycles.  Keeping it plugged in, on the other hand, and using it while it is plugged in, puts just enough charge onto the battery to keep it fully charged, but not enough to use up one of your cycles.

Keep the battery for long periods away from power.  Keep the cord for every-day use.

Even so, don't expect your battery to last more than 3 years if you mostly keep it plugged in, or one year if you cycle it frequently.

I use a laptop as my desktop computer.  It stays plugged in 90% of the time.  My last battery was still giving me 2 hours of operating time when I replaced the computer.  It was 3 years old. (And I only got 2.5 hours out of it when it was new.)

Leave it plugged in unless you [i]need[/i] to use the battery.  Plus, most machines have power management that will slow down the processor, stop the hard drive etc. when it's on battery to conserve power.  This means it will operate slower on the battery than when it is on outlet power.

OK, that about answers my question, thanks, guys.

I have a Gateway Solo 2150. My battery lasted EXACTLY 13 months. Yup 1 month over the warranty period. Coincidence? I really doubt it. I left mine plugged in all the time at work and rarely used the battery power. I'm just wondering if disconnecting the battery would have prolonged the dang thing. A new one is a 'C' note so I'm dragging my feet on getting another. I'd rather give Ammoman a 'C' note on some of his products than Gateway..[:D]

I would only add that if you use the battery, go ahead and use it all the way down and then recharge it. Unless your instruction manual specifically tells you your battery doesn't have memory, this will allow you to avoid that problem.

I had a Toshiba 470 and I kept the battery in pretty good shape with that strategy. I could still get about 1.5 hours out of it after 5 years.

Just about all laptop produced in the last 5 years or so have "intelligent" chargers that regulate charging current based upon the charge in the battery.  If the battery is fully charged and the computer is idle, it willjust get a maintenance "trickle" charge to keep it topped up.  The charger will supply extra current when the computer is no longer idle.

Check your battery's label for memory issues.  If it sez "NiCd," then memory is a problem.  Make sure to go thru a full discharge/charge cycle at least once per quarter.  Partial discharging and recharging can result in the dreaded "memory" effect.

If it sez "Li-ION" or "NiMH," then memory is a non-issue.  Li-ION is the Lithium Ion style, and the NiMH is the Nickel-Metal-Hydride.  Both batteries will not gein memory over time, and also are good for deeper discharge cycles and longer standby times (shelf life.)  Li-ION is preferable to NiMH, and either is sometimes available as an aftermarket replacement for OEM NiCd.  I have several NiMH AA cells that I use for HT radio gear...

Make sure - whatever battery you have - to take the spent batteries to a recycler rather than just throw them away.  Most - if not all - rechargable batteries have "heavy metals" in them, and they can leach into groundwater and the like.  Symptoms of heavy metal poisoning are similar to lead poisoning (it is called lead poisoning because that was the first heavy metal to be in common use.)  Good places to look for recyclers would be larger hardware stores and hobby shops that cater to RC enthusiasts...

FFZ