Is a laptop damaged by always keeping it plugged in?

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If I keep the power cord plugged in all of the time, will it damage my laptop?

Will

Posted 2010-08-01T21:05:21.087

Reputation: 41

1Welcome to superuser.com! Please provide a meaningful title for your questions. "Laptops damage" does not tell anyone what the question is about. I took the liberty to fix this. – sleske – 2010-08-01T21:10:36.083

Answers

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No, quite the opposite. LiIon batteries (which all modern laptops use) wear out from being discharged, so using mains power when possible is advisable.

For more details see e.g. Is it better to use a laptop on battery or on AC power?

Edit:

Actually, the best thing for the battery is to charge it to ~%40, take it out and store it in a cool (not freezing) place, as it deteriorates quicker when it's warm. However, that may not be practical, because

a) some laptops don't work well without their battery and

b) This means you will have to remember to charge your battery before you can actually use its full capacity; this might be annoying if you often use it on the road.

In that case, best thing is to always keep the laptop plugged in, to avoid cycling the battery.

Actually, the best thing is to periodically plug and unplug the battery so it swings between 80-90% charge, but again this is probably not practical, as it has to be done manually.

sleske

Posted 2010-08-01T21:05:21.087

Reputation: 19 887

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If you keep it plugged in, the battery will not have a chance to discharge. This will cause increased temperature and chemical reactions will begin to shorten the life of the battery. This will affect the battery length in the long term, but batteries can be replaced.

It will not permanently damage any components other than the battery.

Basically if you want to keep it plugged in all of the time, remove the battery at about 40% charge and store it in a cool dry place.

MDMarra

Posted 2010-08-01T21:05:21.087

Reputation: 19 580

2-1 LiIon batteries will not deteriorate if they are not discharged (they deteriorate from being discharged). – sleske – 2010-08-01T21:12:40.010

@MarkM: LiIon batteries are mainly worn out by charge/discharge cycles, so avoiding these is important. See e.g. http://www.batteryuniversity.com/parttwo-34.htm

– sleske – 2010-08-01T21:16:16.260

@sleske - Perhaps you should read this - http://thisweekinbatteries.blogspot.com/2010/02/pull-plug-your-battery-will-thank-you.html

– MDMarra – 2010-08-01T21:16:33.170

@sleske - In the article you linked, they even recommend removing the battery if using the notebook on outlet power for extended periods of time... perhaps you should read your own material. – MDMarra – 2010-08-01T21:19:09.450

OK, I see your point, so I take back the -1. I still believe your advice is problematic: The article you link explains that it is better not to fully charge a battery because it will wear out faster. However, unplugging a laptop IMHO is not a good idea because that will actually completely discharge the battery, which will wear it out. As I understand, if you unplug power, drain the battery to ~80%, plugin, charge to ~%90, then repeat, you will indeed increase battery life. However, I don't think anyone will do this.[cont] – sleske – 2010-08-01T21:35:58.933

[...cont] And just unplugging, draining till the low-battery warning, then plugging in again (which is what most people will probably do) will do a full battery cycle, which reduces battery life. So while the advice might work in theory, I don't see it working in practice. – sleske – 2010-08-01T21:37:03.143

2Let's not get religious; it's a battery. Also, I up voted this answer. – James Watt – 2010-08-01T21:44:57.357

@MarkM: As a followup to my posts above: The next article in the series you link to (http://thisweekinbatteries.blogspot.com/2010/02/battery-rules.html) actually says just what I write, namely that deep discharges are bad ("don't swing too wide"). So unplugging is ok, but only for a short while.

– sleske – 2010-08-01T21:51:19.197

@MarkM: Actually, with the edit I now agree with your answer :-). – sleske – 2010-08-01T21:51:57.807