So me and one of my roomates had this little discussion

He was using his laptop and when he plugs it into a power outlet, he takes the battery out. He claims that by doing this he can make the battery life last longer (he also fully understands that if someone trips over the power cord or w/e it will screw him over but that's besides the point.)

I believe that this is utter bs and does absolutely nothing, particularly if it's one of the newer laptops. I didn't see what model laptop he had but he got it new around fall 2007 so it should be pretty new... I've read that if you want to maintain the longevity of a laptop's battery then you should "exercise" it by letting it run only on battery power every couple weeks or so.


But... I could be wrong?


So, what's y'alls take on this? Does taking a battery out when the laptop is plugged into a power outlet help batteries last longer? Whatever the answer is, please show me a source supporting your answer so that I can show this to my roomate (or see for myself that I'm wrong.)

I do believe what your friend is saying, but let me tell you that the only reason I believe in this is because it has happened to all of my cellphones.

If I keep them connected all day, the batteries lifetime is ridiculously decreased, lasting about 4-5 hours off the charger w/o using it.

But I guess you can call me a liar because I never take the battery out of my laptop.

Personally I think your friend is correct because my laptop battery only goes to like 45 mins (use to last two hours) and its only a year old

This website says your friend is right.
http://www.batteryuniversity.com/parttwo-34.htm
"The speed by which lithium-ion ages is governed by temperature and state-of-charge."

Your friend is correct. My laptop battery died just a few months after I purchased my laptop because I always had the cord plugged in. Later I found out that I had to actually use the battery, meaning that I had to charge it and let it discharge by usage like any normal laptop user would do when the laptop is well... a laptop and not intended to use as main computer.

My thought was that if I had the chance of using AC feed why did I need to waste my battery? But yeah, he might actually be doing something good by taking off the battery just remind him to use the battery sometimes.

Whoops if true. I always have my laptop plugged in, it's basically my main computer. I read that website and it says you should do partial discharges and recharges, does this apply to iPods too?

I've had my laptop for like 3 years, and I always leave it plugged in. It would last a little less than two hours when I bought it (then I'd use it for like internet, editing maps or using notepad...), and it still lasts over an hour (now I have tons of programs running like music, various windows, internet, and various other things... I'm very hard on RAM and CPU usage. ... Sometimes it uses my battery slightly while plugged in. I'll see it dip down to like 97% charge. >.>)
About once or twice a week I'll go somewhere and unplug it to take it... And then there I'll use it until the battery is dead or almost dead and then plug it back in and leave it plugged in more.

Oh yeah, did I mention that mine is so messed up that it doesn't even last 5 mins unplugged?

Another friend of mine did the same thing and he has the same issue I have and it's pretty lulzy when we start mocking HP.

My first laptop had a charged state that lasted under 30 seconds at it's end of life.

My current one, I fully charge, then wander around the house, to keep it in good working order.

One of my friends does the remove battery thing.

personally, i know on my laptop that the power adapter actually bypasses the battery while it's plugged in, so it doesnt interact with the battery at all, therefore making it so the battery life isnt reduced. i'm pretty sure most other laptops nowadays do that too, but i could be wrong.

For lithium-ion batteries (which I'm assuming your laptop uses), the rate at which maximum charge decreases is affected by both temperature (hotter = faster loss of max charge) and current charge (more charged = faster loss of max charge).

it's not a good idea to keep your laptop fully charged, unless you're going to discharge it soon. You need a new battery about once every two years anyway. This applies to all batteries. My car's batteries typically run at about 50% charge most of the time, but that's also because it gives them a chance to recharge when I'm coasting.

I just inherited a new laptop, but the battery was destroyed cause my bro left it plugged ALL the time, almost from right after he got it. I just got my new battery, and it's excellent. I make sure it's constantly discharging from a fully charged state, or constantly charging from a fully discharged state.

Now I'm confused. ;o Having gotten my laptop 06/03/06 (I still have the receipt. ), I've always left it plugged in with the battery. Unless my laptop's battery/power configuration is better than I am expecting, shouldn't this mean my battery should last for like 15 minutes? My battery still goes a very long way (though definitely not as long as it used to.) and it's almost always fully charged.

Ya, but it's new. I used to be able to work like 4 or 5 hours without being plugged in.

Interaction isn't what ages Li-Ion. High charge and high temperature is.
Your power adapter charges the battery to 100% (bad) and the running laptop heats the battery (bad).

Ideally keep your battery at 40% charge and in the fridge at 6°C if you're not planning to use your laptop mobile soon.
Only put it in and load it before you want to use it mobile.

I've got a 7 year old laptop with a battery life of zero. Pulling the plug kills it. No joke. Leaving it in sleep lasts for practically ever, though. When I got it about a year ago the battery life was about 30 seconds.

So did my first one, but the difference is I always left that one plugged in.

(Also that I got it in 1999...)