To plug, or not to plug

Stickman

Stickman

Stickman

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Just read in another thread that leaving a laptop plugged into the mains all the time can damage the battery. Thing is, I run a high end 19in laptop and like to run folding/seti on 3 of 4 cores and the GPU all the time, so even brand new the battery would only last about 40 mins.... so the opposite (repeatedly fully discharging and recharging the battery) could also be damaging to it.

So my question is... how many times a week should I let it use up the battery and recharge it for the longest life: once a day? once a week? (mains power is always available, I just don't want to shorten the battery life by constant charging).

Suppose I could run it on mains with the battery removed but that would be a bit of a pain when I wanted to put it away unplugged or move it etc...

Any ideas?
 
Just heard in the other thread that it's not the constant charging, but the heat from the laptop that shortens the battery life.... if so I may be ok leaving mine plugged in as it's designed with the battery at the near (front) edge and the fans suck in air from behind here and blow it all out the back.... so no heat flow from CPU/GPU etc goes near the battery... maybe I'll be ok leaving it plugged in then?
 
Leaving it plugged in all the time is fine, as I said in the other thread, if you unplug it for even 1minute, you should really discharge it and fully charge it again to keep the battery peforming at its best.
 
Bubba said:
Leaving it plugged in all the time is fine, as I said in the other thread, if you unplug it for even 1minute, you should really discharge it and fully charge it again to keep the battery peforming at its best.
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But batteries only have a certain amount of cycles before they die? Would letting it discharge completely be okay? Since it will shorten the cycles?
 
I always take the battery out if I'm going to be using the laptop from the mains for an extended period. The laptop I sold recently was three years old and still giving over an hour on the battery.

I thought lithium ion batteries didn't suffer from 'memory' problems like NiCad and, to a lesser extent, NiMH so shouldn't need a deep discharge for every charging cycle. In fact, because they have a lower number of charging cycles than nickel-based batteries, partial charging was actually preferred.
 
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Fully discharging a lithium cell will reduce its lifespan. For maximum longevity keep the battery between 20-80% charged. Charging the final 90->100% is also detrimental to lifespan, more than say charging from 50->60%. Lithium cells self-discharge over time, so by keeping the battery permanently connected the laptop will sense when it gets just a couple of % below max and will dutifully resume charging until full. Remove the battery if you don't need it and only recharge it if you haven't used it for a couple of months. The cells should last for 3-5 years this way.
 
Leave it plugged in all the time, the battery is only good to protect you from a power cut in this type of huge laptop.
 
Leaving a Li-ion battery in a fully charged state also reduces it's life. Charge it around 70% and take the battery out, store it somewhere cool and run the laptop on the charger only.
 
Dogbreath said:
Leaving a Li-ion battery in a fully charged state also reduces it's life. Charge it around 70% and take the battery out, store it somewhere cool and run the laptop on the charger only.
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But the battery in a 19" is worthless, having the battery working as a UPS to protect against power cuts is a much better use even if it reduces its life.
 
POB said:
But the battery in a 19" is worthless, having the battery working as a UPS to protect against power cuts is a much better use even if it reduces its life.
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bull twang, even a big laptop still gets some life out of the battery, for instance if you need a PDF in view when working under a car in the garage, showing a quick homevideo/youtube at your old folks gaff etc.

Keep in on the shelf half charged for the win.
 
Hmmm. Seems there's no consensus on this.... Guess I'll just have to use it how I normally would and wait and see what happens. Thanks anyways. :)

edit: btw, if it helps, just took it out and noticed it's a 44Wh 10.8v Lithum-Ion battery.
 
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I've always removed the battery from my notebooks when I was using them on mains, something which was obvious when I came to sell them a year or two later and the batteries themselves were still perfectly healthy.
 
As far as I'm aware, you should use the mains as much as possible, when you can. That's in a mobile laptop, though.

Desktop replacements should indeed be left with a good charge and removed when plugged in for long periods.
 
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