61

Am I "hurting" my HP laptop by leaving it running, unplugging from outlet - walking a few feet and plugging it back in? My brother-in-law says I am.

Burgi
  • 6,493
  • 14
  • 39
  • 52
Donna
  • 531
  • 1
  • 4
  • 4
  • 81
    No, this is common practice. – Moab May 09 '16 at 00:05
  • 8
    There is a minuscule chance of damaging the power supply, just as there is every time you go through a power cycle. There is a lot more chance of damaging the laptop by dropping it than by changing the power outlets. – AFH May 09 '16 at 00:24
  • @AFH - no kidding - when I consider how many people I see wandering around my office building - going floor to floor via elevators or _stairs_ - while holding their laptop to their chest while it's _open_ - I just wonder how many cracked screens the company is paying for. (Don't these guys have laptops that _sleep_?) – davidbak May 09 '16 at 16:15
  • 12
    @davidbak I think that's the problem: they do not wish their computer to sleep (on some platforms, recovering from sleep is noticeably slower than not recovering from sleep, it interrupts wifi, or forces a lock screen [potentially requiring a domain controller to authorize the unlock]). Since the laptop sleeps, by default, every time they close the lid, they don't close it. Of course one can adjust the power setting, but that isn't known to all laptop users. – Calchas May 09 '16 at 16:24
  • 3
    Yes, if you're not on battery! (e.g. data corruption) – Andrew T. May 10 '16 at 03:55
  • Yep there is no probleme with this practice – David Ansermot May 10 '16 at 11:17
  • Omitting the debatable _memory effect_ I remember the problem of the [membrane](https://en.wikipedia.org/wiki/Separator_%28electricity%29) deterioration. It can be slightly accelerated by each inversion in the ions flux direction. When you pass from the charge phase to the discharge one, ions change the direction they pass through the membrane. Many inversions increase the hole sizes and their number. This accelerates the discharge rate of the battery, _from inside_, and increases the charging time (because it is discharging in the same time)... It should be nice to post updated references... – Hastur May 10 '16 at 17:38
  • @Moab _To be common does not make a practice good, not necessarily._ `:-)`. Nothing personal, just I've seen too many times common behaviours dictated by ease, indifference, laziness, momentary convenience, lack of knowledge or simply imitation... – Hastur May 10 '16 at 18:01
  • It is so normal behavior, that if you would do this and your laptop had a problem after that, it would be enough reason for a free repair / replacement in the warranty period. – peterh May 11 '16 at 01:54
  • I think a good question is if there's a difference between the computer being asleep or not. What if it's busy writing to the hard disk at the very moment you plug it in? Will there be a power spike that can affect things? – Mr Lister May 11 '16 at 06:49
  • @Donna I know someone practically always asks this question and it can get annoying, but why do you want to do this? We might help you find a better solution to the deeper problem (if there is one) if we know. I doubt there is a deeper pertinent problem, but just in case, I thought I'd ask. – Brōtsyorfuzthrāx May 11 '16 at 08:09

4 Answers4

72

Nope, it should be fine. Laptops are designed to switch between battery and mains power.

Stuff to watch out for? Tripping hazards. While barrel connectors are fairly robust, they've been known to fail — especially with a sideways force. Unplugging the power connector totally would mitigate both this and tripping risk. While there are special mechanisms for laptop HDDs that park the head, this is in case you drop it.

In essence, anything that can kill a laptop while moving it would kill it anyway. I've had a few desktop divas experience the same failure modes, so... it's not especially dangerous to move a laptop.

TRiG
  • 1,310
  • 1
  • 15
  • 33
Journeyman Geek
  • 127,463
  • 52
  • 260
  • 430
  • 2
    +1 I've busted 2 laptop power... ports? holes? whatever the term is... by dropping it sideways and it landing on the plugged in cord. In the same vein as tripped hazards, make sure you have a good grip on it; dropping has a very similar effect. – jpmc26 May 10 '16 at 00:10
  • 6
    I'd really move a laptop after unplugging everything. I'm a klutz – Journeyman Geek May 10 '16 at 00:41
  • 1
    "I've busted 2 laptop power... ports? holes? whatever the term is" DC jack is the proper term :-) – Moab May 10 '16 at 01:23
  • I've had both sides break on different systems. I've also gotten into massive amounts of pedantry with 'sockets' 'jacks' and so on. Connector seems reasonably gender neutral. – Journeyman Geek May 10 '16 at 01:27
  • Much care should be taken when handling a device with a running hard drive as it can hurt it. Moving a running laptop with a hard drive is a bad idea. – Julie Pelletier May 27 '16 at 06:12
25

Your brother-in-law has an outdated view of how rechargeable batteries work. Older laptops used NiCd batteries were susceptible to the memory effect. Their maximum charge could be reduced if they were repeatedly partially discharged and then charged. There were all sorts of attempts to mitigate this, including waiting until the battery was discharged before charging it again. It's debatable whether the memory effect was real.

Modern laptops use lithium-ion batteries which have no such problem. They also have sophisticated hardware and software to monitor the battery, keep it in good condition, and prevent anything a consumer is likely to do from harming it.

Schwern
  • 2,196
  • 1
  • 23
  • 37
  • 1
    Maaaan. I don't remember the last time I saw a NiCd powered laptop. Late 90s? – Journeyman Geek May 10 '16 at 06:51
  • There is not only the _"debatable memory effect"_ but even the _membrane deterioration_ one (eventually see above the comment to the question). Technique makes progresses and materials changes each day, but I shouldn't be so strict judging the brother-in-law, even if they always get wrong, by definition :-). – Hastur May 10 '16 at 18:09
  • 2
    For what it's worth, the old NiCd packs had such horrible problems with memory effects because the manufacturers were cheapskates. The packs were designed for the computer to work while each cell was in the 1.2-1.5v range. For NiCd batteries this is the "overcharge" zone and holds relatively little power. The vast majority of the cell's power storage is in the 1.2-1.0v range. I rebuilt a few packs and added one more cell so the pack was operating in its main range instead of overcharge and the run-time tripled, as well as being able to properly discharge the cells to avoid memory problems. – Perkins May 10 '16 at 18:58
  • I don't see any indication in OP's question that this is the source of the BIL's cluelessness. – R.. GitHub STOP HELPING ICE May 10 '16 at 22:16
  • 1
    @R.. Sure, the brother-in-law could think it will spook the electricity ponies that make the laptop go. I'm making an educated guess based on the rationale behind questionable advice I've heard about laptops over the last two decades. – Schwern May 10 '16 at 22:21
  • @JourneymanGeek NiCd?! Luxury! I remember the old mac portable that had a lead battery the size of something you'd pull out of a motorcycle. Mind you, if you did roast the battery in those days you could just pull out a set of jumper cables and bring the car around to give the laptop a boost. 0_o – J... May 11 '16 at 02:45
  • Dropping a lithium ion battery on the other hand, can reduce its charging capacity. – Brōtsyorfuzthrāx May 11 '16 at 08:15
5

Unless your laptop doesn't have a battery, you're fine. Leaving it plugged in all day, everyday can minutely reduce your battery's efficiency. But since your battery degrades overtime anyway, that's not really an issue. Lithium batteries don't last forever, nor retain their peak efficiency indefinitely.

NonCreature0714
  • 277
  • 2
  • 6
  • 11
    The control circuit for a Lithium Ion battery is such that leaving it plugged in is unlikely to noticeably degrade your device. I'd be more concerned about a fire from overcharging, if the circuit failed. – Gusdor May 09 '16 at 13:26
  • 7
    @Gusdor I think this has become conventional wisdom because it was much more likely to be true of Nickel-Cadmium batteries. – Random832 May 09 '16 at 14:22
  • 1
    Ah, true - she didn't specify whether she had a lithium or nickel cadmium battery. Or how recent her laptop is. The answer would change based on her laptop model, but still be mostly ok. – NonCreature0714 May 09 '16 at 14:31
  • @Random832 good shout. I wasn't aware of the distinction. – Gusdor May 09 '16 at 14:32
  • 4
    @Gusdor two of the many, many things that shorten the life of a Li-ion are being kept at full charge (for example because a laptop is keeping it topped off) and being kept at high temperature (for example because it's stuck inside a running laptop). It's a really sensitive chemistry. – hobbs May 09 '16 at 15:06
  • For more info about prolonging your Li-ion battery: http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries – Wayne Werner May 09 '16 at 18:25
  • LOL - The statement was both something I've actually seen – a network security person I once knew refused to keep a battery in their laptop, and ran kali linux from a disc (the person also replaced subcomponents daily, super paranoid) – and was an amusing illustration which was called to my mind because of it. No harm meant, but certainly a little humor. :) – NonCreature0714 May 10 '16 at 05:05
  • @NathanOsman Consumer laptop batteries usually don't last very long: 2 years, maybe 3. And when they are worn the laptop keeps recharging them continuously with eats a lot of power (without much benefit) and produces a lot of heat (which keeps the noisy fan going continuously and make using the laptop unpleasant). Buying a replacement battery usually doesn't make sense. Expensive and in some cases impossible (model gone out of production). In that case taking the battery out and running the laptop only from the mains starts looking attractive. – Tonny May 10 '16 at 15:07
  • 1
    @Tonny As someone who is currently replacing the battery in their still otherwise fine 2011 laptop, I must disagree. – Schwern May 10 '16 at 22:34
  • @Schwern I said usually, didn't I ? I've got a 2006 laptop myself for which I bought a new battery in 2012. In my case it did make sense as this laptop has a matte 1600x1200 screen (15.6", they don't make those anymore) and, with Linux, still has enough performance for my usage. At €90,- the battery was reasonably priced. – Tonny May 11 '16 at 10:53
0

Yes you are but not in the way you think. Unplugging it and replugging is fine however hard drives are not designed to be moved while in use and are extremely fragile and easily damaged by bumps that would be safe while the laptop is not in operation.

JamesRyan
  • 1,671
  • 1
  • 12
  • 20
  • 4
    Many modern laptops have an SSD today, which is not susceptible to heads crashing due to vibration or movement. – dotancohen May 10 '16 at 11:37
  • 3
    @dotancohen Surprisingly enough SSDs in laptops are still quite rare, in all but the higher end, because of the added cost. But what you say is right if it has one. – JamesRyan May 10 '16 at 11:47
  • 8
    Most every laptop I've seen in the past 10 years or so also has acceleration sensors and driver-level software to turn off spinning disks to prevent damage to the hard drive in the event of acceleration that would crash the disk heads, so this isn't likely to be an issue. – HopelessN00b May 10 '16 at 14:07
  • 1
    Modern spinning disk hard drives, especially 2.5", are not "extremely fragile". Laptops are designed to be moved while in use, otherwise they'd just be a portable desktop Their drives will not be easily damaged by a bump. Just don't drop your laptop, but [even that isn't so bad anymore](https://en.wikipedia.org/wiki/Active_hard-drive_protection). – Schwern May 10 '16 at 22:31
  • 1
    @Schwern "Laptops are designed to be moved while in use" no they are not. Look at your manual, all the main manufacturers currently advise against it. Active shock protection only works against a fall, it does not work against bumping it on a desk or the gyroscopic forces of tilting it. Laptop drives can withstand many G shocks while the heads are parked but not while the heads are active. – JamesRyan May 10 '16 at 23:22
  • 3
    @JamesRyan I'm pretty sure Apple will not void my warranty because I walk around with my Macbook open. Every hard drive has a shock (in g's over time) and vibration (in Hz and g's) tolerance while operating and not operating. For example, [this Toshiba drive](https://www.cdw.com/shop/products/Toshiba-DT01ACA100-hard-drive-1-TB-SATA-6Gb-s/2867314.aspx) can handle 70g's over 2ms and 5-500 Hz of vibration at 0.5g's while operating. [The specs for the Seagate Barracuda](https://www.seagate.com/files/staticfiles/support/disc/manuals/desktop/Barracuda%207200.8/100325576f.pdf) are similar. – Schwern May 10 '16 at 23:43
  • 1
    @Schwern sounds impressive until you consider that a laptop dropped from 10cm onto a ceramic floor experiences more than 300G over 2ms. Plonking a laptop heavily onto a desk can easily go above 70G and *will not* always activate the shock protection. So moving around a laptop is only fine when you treat it as fragile and put it down gently. The drive records the max shock it has been exposed to in operation so yes Apple will void your warranty when they can see damage caused by shock. – JamesRyan May 11 '16 at 11:36
  • I regularly am stuck with a long winded operations in Windows and Linux, and therefore move the laptop while in use, even with running and or copying to/from USB drives. No problem yet. On the other hand a small move of an internal harddrive (not attached with screws) while using dd on Linux resulted in a bricking of the (old, second hand) drive. Probably the age was partly at fault. – vinnief May 24 '16 at 05:46