Laptop Battery care - tips?

slash000

So, about 7 or so months ago, I got a new laptop. With it, a high-capacity battery. The thing was claimed to allow me to run the battery on moderate settings for 6.5 hours or so.

However, after about 6 or so months of use of the laptop, I noticed that my laptop would only run for about 2 hours on a 100% charge, and then only with wifi off and the screen totally dimmed.

Knowing that to be bullshit (my friend's laptop, which is 8 months old, same type, runs for 6.5 hours with wifi and screen turned on), I'm having the battery replaced.




Since this is my first laptop, I have to ask - What can I do to preserve my battery's maximum life?



All I know is that deep discharges are supposedly bad; and yet, I've read websites that recommend deep discharging once to "calibrate" the battery... (?)



What habits should I pick up to make sure that my new laptop battery doesn't drop from ~6 hours of life to ~2 hours of life in less than half a year?

The Dude With Herpes

Hmm....Don't charge it a lot if it's not empty.

I had a bad habit of using my laptop for like half hour at a time away from the plug, and when I put it back i'd just plug it back in. Ignoring the debate over "battery memory" I can say with certainty that this diminished the life of my battery; I noticed the exact same thing on my MP3 Player (then a Zen Xtra). So what I started doing is having 2 batteries; one I use when I'm plugged in and one I use when I'm away. I will swap the batteries out until the "away" battery is completely depleted then I'll make it my "home" battery and use the other as "away". Fully discharging the battery seems to make it last longer and not get the controversial "memory" stuck at a low fill.

This has worked great for me and I've had the batteries for 3 years, no problems, still get full use of them.

That's really my only suggestion.

Gihgehls

I'll just quote myself again on this one.

Gihgehls wrote: »

Lithium ion packs are limited to a (estimated) number of charge/discharge cycles. This number goes up as stress on the pack decreases. You will get far more life out of your lithium ion batteries if you just leave them on the damn charger, as charging from near zero is more stressful for the battery than charging up from 80%. The only possible downside of constantly charging a lithium ion battery is that the smart guage will slowly lose calibration. But that is only a meter, it isn't the actual capacity of your battery that is changing.

Also, lithium ion batteries cannot be taken down to 0% without permenant damage to the pack. This is why it is dangerous to let most lithium ion devices discharge too much. Eventually that little clock we all have in just about all devices will ruin the battery, and it will never hold as much power as it used to. (side note: if your Li-ion device shows no battery remaining, it is still probably hiding 5 or 10 percent from you, for its own safety.)

For what it is worth, lithium ion batteries also have a "shelf-life" which is usually a few years from their date of manufacture. Eventually they will just wear out, even if you don't use them, which is why it is also a good idea not to stress out too much about the number of charge/discharge cycles you have left, because the pack is going to die anyway no matter how much you baby it.

Most battery packs are made of seperate cells (think of those battery packs that look like a bunch of AA batteries strapped together.) The reason they tell you to charge it so long is to ensure that all the cells are balanced. Heat, age, and manufacturing variances affect the internal resistance of a cell, and the internal resistance affects how quickly current is drained from it. In a severely unbalanced pack, many of the cells might be doing no work at all and will drastically affect the appearent capacity of the battery.

tl;dr: Keep that shit plugged in as often as you can for the best possible performance from your battery.

astroboy

I figure this is as good a place to ask as any:

My boyfriend uses his laptop like a desktop PC, it's primarily his home computer. Everyday he turns it on to use it, then turns it off every night when he's done with it.

I've heard that it can wear on a laptop if you power it up and down so often. Is it harmful? Would it be better if he just put it into sleep mode, rather than turning it on and off every day? If it's always plugged in at home, should he ever fully turn it off?

DesertBox

My old Toshiba laptop came with instructions to discharge the battery as low as you can (like 5% capacity) at least once a month to preserve the battery life. The thing crapped out on me (system board, i was told) after a few years but its battery life never dropped significantly. So take that anecdote as you will.

slash000

The thing is, I've just about kept my Li-on battery plugged in at all times. It's just that when I first got it, it was ~6 hours, then several months later (6 or 7 months), I tried running it off the battery, and it gives me about ~2.5 hours. And that's actual hours, because I used it during a class until it ran down and asked me to save my work and shut it off.


What I think may actually be more useful is actual experience from people with laptops. What has worked for you? What do you do that keeps your laptop battery working at a decently long battery life?




Also, i read something that said if your battery gets funky like mine, then it might help to fully discharge it then fully recharge it to "reset" the internal "gauge" telling it how much charge it can hold... good/bad idea?

slash000

Indeed, I think practical real-life experience is just as useful as hearing the theory behind Li-ion technology. If you use your laptop a certain way and have never expereinced battery life problems, I want to hear it.

slash000

Personally, I fully charged my laptop on Day 1, and then only ran it down to near-zero a single time; after that it was plugged in virtually 100% of the time until the other day when I noticed it only runs for about 2 or 2.5 hours now.

Is it a good or bad idea to leave it plugged in and 'charging' even when the battery is at 100%?

Daedalus

slash000 wrote: »

Is it a good or bad idea to leave it plugged in and 'charging' even when the battery is at 100%?

As has been said before, yes, it's fine. When your battery is at 100%, your charger goes into "trickle" mode, where it only gives the battery as much power as it's using up.

Lithium ion batteries decay pretty linearly with time regardless of what you do with them as long as you don't a) drop the charge to 0% too often, or b) expose it to very low or very high temperatures. (They're really surprisingly sensitive to below-freezing temps, although I've noticed this much more with non-rechargable lithium cells). Did the UPS packagebreaker leave your laptop battery on a snowy doorstep for a day or two?

minor incident

Gihgehls wrote: »

I'll just quote myself again on this one.

Gihgehls wrote: »

Lithium ion packs are limited to a (estimated) number of charge/discharge cycles. This number goes up as stress on the pack decreases. You will get far more life out of your lithium ion batteries if you just leave them on the damn charger, as charging from near zero is more stressful for the battery than charging up from 80%. The only possible downside of constantly charging a lithium ion battery is that the smart guage will slowly lose calibration. But that is only a meter, it isn't the actual capacity of your battery that is changing.

Also, lithium ion batteries cannot be taken down to 0% without permenant damage to the pack. This is why it is dangerous to let most lithium ion devices discharge too much. Eventually that little clock we all have in just about all devices will ruin the battery, and it will never hold as much power as it used to. (side note: if your Li-ion device shows no battery remaining, it is still probably hiding 5 or 10 percent from you, for its own safety.)

For what it is worth, lithium ion batteries also have a "shelf-life" which is usually a few years from their date of manufacture. Eventually they will just wear out, even if you don't use them, which is why it is also a good idea not to stress out too much about the number of charge/discharge cycles you have left, because the pack is going to die anyway no matter how much you baby it.

Most battery packs are made of seperate cells (think of those battery packs that look like a bunch of AA batteries strapped together.) The reason they tell you to charge it so long is to ensure that all the cells are balanced. Heat, age, and manufacturing variances affect the internal resistance of a cell, and the internal resistance affects how quickly current is drained from it. In a severely unbalanced pack, many of the cells might be doing no work at all and will drastically affect the appearent capacity of the battery.

tl;dr: Keep that shit plugged in as often as you can for the best possible performance from your battery.

I spent quite a bit of time as a technician (for Apple), and I can attest to this being the ABSOLUTE BEST way to maximize your battery life. Fully discharging and fully charging is a BAD idea with current Li-Ion batteries, as it will only add "cycles" more quickly than just keeping it topped off.

slash000

Daedalus wrote: »

Did the UPS packagebreaker leave your laptop battery on a snowy doorstep for a day or two?

No, it was delivered to my apartment and I took it inside immediately. And like I said, initially, the charge was fine, I was getting ~6 hours.

Daedalus wrote: »

slash000 wrote: »

Is it a good or bad idea to leave it plugged in and 'charging' even when the battery is at 100%?

As has been said before, yes, it's fine. When your battery is at 100%, your charger goes into "trickle" mode, where it only gives the battery as much power as it's using up.

Lithium ion batteries decay pretty linearly with time regardless of what you do with them as long as you don't a) drop the charge to 0% too often, or b) expose it to very low or very high temperatures.

It's not that I don't believe this sentiment, it's just that I did leave my battery "topped off" for just about 6 straight months, fully charged, plugged in nearly any time it was in use.. Since it wasn't exposed to anything but room temperature, I'm afraid (but obviously not certain) that the cause of its now-very-low battery life was due to it always being plugged in and virtually never having been discharged..

I mean, I would use it for like, 20 minutes or something on the battery, then plug it back in. Rarely did I ever not have it plugged in..

slash000

I did deep discharge it one time, though. It didn't go to completely zero, because it gave me a blank-screen, no-operating-system, message that said, "Your battery is nearly depleted. Please plug into an AC Outlet to recharge."

That was once; I wouldn't think a single deep discharge could totally wreck a battery's life..?

slash000

This is all pretty confusing to me. I mean, with my DS and GBA and music device, I would always fully charge them, then use them until they were nearly empty - when the gba/ds would give me the orange LED, or my mp3 player indicator would say 10%. Then I would plug them in and fully charge them to maximum, and then use them again until they were nearly depleted. My GBA, DS, and MP3 player have had no problems maintaining battery lives largely the same as when they were new.

So I was shocked when I found out one day that my laptop would only run for ~2 hours.. I thought what I was doing was the best way to maintain the laptop battery - keep it plugged in and at 100% just about as much as possible.


So while I was considering running my laptop the way I run my GBA/DS/MP3, I know that you guys are pretty certain that doing things the way I had been is the best way..

But even if I can have my laptop fully charged, then run down, repeat, that might add to the cycles, but if it causes my battery to lose capacity down to 80% over 2 years, that's a million times better than going down to 40% in half a year..


this is why I'm concerned..

Nedo

i think it highly depends on the quality of the battery

i´ve put my laptop always on charge, never really let it work from battery and i´m stuck with 50 % battery life after ~ 2 years. the battery of my DSLR (Canon Eos 350ed) i discharge almost fully and then charge it, or charge it before a important day (work etc...) and it still runs fine.
been very carefull with my mobile, fully discharging it and fully loading it, like some people say and that didnt work out that well. i guess there is more influence to a battery in the actual quality of the fabrication instead of charge/recharge cycles

slash000

Well, I don't know if this is a 'quality' battery or not; it's an official Dell battery. My friend with the same laptop type and battery type hasn't had this problem. But she sort of runs off battery most of the time, but I don't think she ever really lets it get below 25% battery before recharging... maybe.. that's what I should start doing..?

DesertBox

Well I found something interesting in wiki

http://en.wikipedia.org/wiki/Lithium-ion_battery

At a 100% charge level, a typical Li-ion laptop battery that is full most of the time at 25 degrees Celsius or 77 degrees Fahrenheit will irreversibly lose approximately 20% capacity per year. However, a battery stored inside a poorly ventilated laptop may be subject to a prolonged exposure to much higher temperatures than 25 °C, which will significantly shorten its life. The capacity loss begins from the time the battery was manufactured, and occurs even when the battery is unused. Different storage temperatures produce different loss results: 6% loss at 0 °C (32 °F), 20% at 25 °C (77 °F), and 35% at 40 °C (104 °F). When stored at 40% - 60% charge level, these figures are reduced to 2%, 4%, 15% at 0, 25 and 40 degrees Celsius respectively.

Of course that's got a big "Citation Needed" above it, but it could be a hint. Does your laptop or the battery get hot while you use it?

I know my laptop gets hot even when its plugged in so I bought a laptop cooler, which I keep under it at all times.

slash000

I've read those same numbers at various tech websites..

My laptop gets warm, but not really ever hot, though.

0blique

What I took from that article is that it's better to keep your battery charged at 40-60% (ie, unplug and replug in your battery when it reaches the limits). Of course, I found that it was annoying to keep up, and easy to screw up (leading to a discharge cycle), so I don't bother anymore.

What I've heard that some people do is remove their laptop batteries, and run it from an outlet. Obviously, this is only practical if you're using it as a desktop.

elevature

0blique wrote: »

What I've heard that some people do is remove their laptop batteries, and run it from an outlet. Obviously, this is only practical if you're using it as a desktop.

This is what I do. My laptop is my main computer, it's on and plugged in pretty much all day every day. I have the battery in when I'm in class, but as soon as I get home I pop it out and just keep the laptop plugged in. I was told long ago that this was a good for the battery; I'm not sure if that's true or not, but it has about the same charge now as it had two years ago when I got it (which is around 2.5-3 hours depending on the settings).

ArcSyn

I have had a Dell Latitude for almost a year, and here's a few of my tips:

1: Use your battery.
It's not good to leave it plugged in all the time. It's not good to drain it to 0 before plugging it in all the time. Moderation is key, which could practically be said of almost anything. At work, my laptop is on a dock most of the time, but when I'm home it's on and off battery a lot as I usually use it unplugged until it gets low or if I know I'm going to be draining it quickly (gaming, video editing, etc).

2: No extremes.
I mentioned this above, but don't always leave it plugged in. Don't always drain it until it shuts off before charging it.

3: Expect some loss of capacity.
No battery is perfect, though they are much better now. When I first got my laptop, using Wifi and full brightness on the screen, but no CD or intense operations, I had about 3 hours of runtime. Now, a year later I'm looking at about 2.5 hours. I think that's acceptable.

4: Power (since it was asked above)
So long as it's shut down and powered on normally, powering it on and off is fine. I power my laptop on and off multiple times per day, and let it sleep (not hibernate - that is evil) multiple times as well. It's perfectly fine a year later.

So yeah, if you have a laptop, go and use it. It's not worth babying the thing. Though I do recommend getting the accidental coverage simply because it's worth it in my opinion with the price of laptops these days.

slash000

Hm. That sounds like good advice. it seems that most of you posting here with actual experience seem to agree that not using the laptop to the "extremes" of always-plugged-in or always-charged-down/recharged seem to have the best luck; whether you do so by switching between home/away batteries or simply by using it unplugged until/unless doing something that runs it down quickly.

I think I'll start taking the battery out when I have to plug the laptop in after having charged the battery.


As far as accidental coverage, yeah, I'm getting a brand new battery for no extra charge over this. That's why I'm wanting to hear opinions; so that the same thing doesn't happen again to my brand new battery that's coming in the mail.

minor incident

ArcSyn wrote: »

1: Use your battery.
It's not good to leave it plugged in all the time. It's not good to drain it to 0 before plugging it in all the time. Moderation is key, which could practically be said of almost anything. At work, my laptop is on a dock most of the time, but when I'm home it's on and off battery a lot as I usually use it unplugged until it gets low or if I know I'm going to be draining it quickly (gaming, video editing, etc).

Totally false. It's far better for it NOT to go through charge cycles. Leaving it plugged in at all times mitigates this somewhat, as most laptops will top off the battery and then proceed to trickle charge as needed while it alternately runs off of battery and AC power. Draining down to 0 all the time is bad. Draining it down halfway is also bad. Neither is BAD BAD, but acceptable bad. The best course of action is to leave it plugged in, or just remove the battery all together when using your laptop.

ArcSyn wrote: »

3: Expect some loss of capacity.
No battery is perfect, though they are much better now. When I first got my laptop, using Wifi and full brightness on the screen, but no CD or intense operations, I had about 3 hours of runtime. Now, a year later I'm looking at about 2.5 hours. I think that's acceptable.

This much is true, and people need to accept it. Li-Ion is good, but not perfect by any means.

slash000

Minor Incident, do you personally own a laptop? If so, do you keep yours plugged in as much as possible?

I ask because I like to know what people's personal experiences are as well as the theories behind them.





For me, I'd rather do something that causes my Li-ion to lose 20% of its capacity over 1 or 2 years than have it lose 60% capacity in half a year. I know liion batteries lose capacity with time, I'm just trying to mitigate the problem... I just can't figure out if the best way to mitigate it is by having it plugged in as much as possible, or to have it charged up then unplug then use it for a while then recharge etc. or use it in moderation or whatever.

minor incident

slash000 wrote: »

Minor Incident, do you personally own a laptop? If so, do you keep yours plugged in as much as possible?

I ask because I like to know what people's personal experiences are as well as the theories behind them.

For me, I'd rather do something that causes my Li-ion to lose 20% of its capacity over 1 or 2 years than have it lose 60% capacity in half a year. I know liion batteries lose capacity with time, I'm just trying to mitigate the problem... I just can't figure out if the best way to mitigate it is by having it plugged in as much as possible, or to have it charged up then unplug then use it for a while then recharge etc. or use it in moderation or whatever.

I've got a few around the house currently, and I keep one plugged in 24/7, one is my "carry around" notebook, another is my wife's which she uses at various places.

In my experience (and according to the engineering department and every technical document I had access to at Apple) all the laptops that remain plugged in and fully charged go through fewer charge cycles, and thus have a longer, fuller lifespan.

elevature

So what's better, leaving the battery in and the laptop plugged in all the time, or just to take the battery out?

Brodo Faggins

I've had my laptop for 3 years now, and I still get three and a half hours with screen at half brightness and wifi on. When I go to class I never use more than 50%; when I get home I charge it fully, then take the battery out. Less heat stress on the battery = longer life.

minor incident

elevature wrote: »

So what's better, leaving the battery in and the laptop plugged in all the time, or just to take the battery out?

Option 1 is good practice (if not always possible).

Option 2 is even better (if even less feasible).

Ego

It used to work for six hours. Now it works for two hours.

Your battery is obviously fucking broken. The above has nothing to do with how often you charged it or drained it.

edit: lithium ion batteries break down naturally just by sitting there, full or empty. The warmer the battery is, the quicker this process of decay will occur. Li-ion batteries are generally considered to be perishables. Just use them till they don't last, and replace them. They're a lot less durable in terms of actual cycles than older rechargeables are.

minor incident

Ego wrote: »

It used to work for six hours. Now it works for two hours.

Your battery is obviously fucking broken. The above has nothing to do with how often you charged it or drained it.

He's probably right. At Apple that was grounds for classifying it as a defective battery. Assuming you haven't put 300 charge cycles on the thing in six months, which is unlikely, you've got a bad battery.

slash000

Ego wrote: »

It used to work for six hours. Now it works for two hours.

Your battery is obviously fucking broken. The above has nothing to do with how often you charged it or drained it.

edit: lithium ion batteries break down naturally just by sitting there, full or empty. The warmer the battery is, the quicker this process of decay will occur. Li-ion batteries are generally considered to be perishables. Just use them till they don't last, and replace them. They're a lot less durable in terms of actual cycles than older rechargeables are.

Obviously it's broken. My question is this:

1. What was the likely cause of it breaking?

2. Now that I have a new battery, what can I do to prevent the new one from breaking?


Obviously Li-ion batteries degrade and lose capacity over time. It's just that they don't normally go from 6 hours to 2 hours over the course of half a year.

IceBurner

slash000 wrote: »

Obviously it's broken. My question is this:

1. What was the likely cause of it breaking?

2. Now that I have a new battery, what can I do to prevent the new one from breaking?


Obviously Li-ion batteries degrade and lose capacity over time. It's just that they don't normally go from 6 hours to 2 hours over the course of half a year.

1. Defective manufacture.

2. Part 1 - Follow the instructions. Wikipedia's LI-ION article has a wealth of sourced information which corrorborates the advice given in this thread from instruction booklets.

Part 2 - Invent time travel, go back and (through leet Crane Operator skills or by excessive violence) convince the people who have shaped the business world of today that producing quality goods in the first place trumps being cheapskates who prefer the savings of crap mass-produced on the principle of "acceptable yields". LI-ION batteries are heinously expensive to produce due to the rare Earth elements needed. The manufacturers have obviously cut corners wherever possible and likely in places they shouldn't. Do not expect any semblance of quality.

DesertBox

ArcSyn wrote: »

I
4: Power (since it was asked above)
So long as it's shut down and powered on normally, powering it on and off is fine. I power my laptop on and off multiple times per day, and let it sleep (not hibernate - that is evil) multiple times as well. It's perfectly fine a year later.

Why is hibernate evil? I use it all the time.

slash000

OK, I tried a tip I saw on the web with my busted battery, and I do NOT recommend this, but it certainly helped given the circumstances --

I completely deep discharged my laptop, then immediately recharged it to 100%


What occurred during discharge was that the laptop battery indicator would run down to about 7% and then was stuck there for another hour or so. Meaning, there was more juice, but the internal gauge didn't really "know" that apparently...


Once I was back to 100% I was able to use the battery for about 3.5 to 4 hours instead of 2 to 2.5 hours. This is with wifi off and screen totally dimmed of course (just like the 2/2.5 life).


So the battery isn't totally useless, but I've nevertheless recieved a replacement battery from Dell.


Like I said, I don't recommend purposeful deep discharges for any reason. But for me, this little tip worked. I only used it because I knew I was getting a new battery anyway, at that.





NOW.


Wikipedia says this:

* Unlike Ni-Cd batteries, lithium-ion batteries should be charged early and often. However, if they are not used for a long time, they should be brought to a charge level of around 40% - 60%. Lithium-ion batteries should not be frequently fully discharged and recharged ("deep-cycled") like Ni-Cd batteries, but this is necessary after about every 30th recharge to recalibrate any external electronic "fuel gauge" (e.g. State Of Charge meter). This prevents the fuel gauge from showing an incorrect battery charge.[13]
* Lithium-ion batteries should never be depleted to below their minimum voltage, 2.4v to 3.0v per cell.
* Li-ion batteries should be kept cool. Ideally they are stored in a refrigerator. Aging will take its toll much faster at high temperatures. The high temperatures found in cars cause lithium-ion batteries to degrade rapidly.
* According to one book,[35] lithium-ion batteries should not be frozen (most lithium-ion battery electrolytes freeze at approximately −40 °C; however, this is much colder than the lowest temperature reached by household freezers).
* Li-ion batteries should be bought only when needed, because the aging process begins as soon as the battery is manufactured.[13]
* When using a notebook computer running from fixed line power over extended periods, the battery should be removed,[36] and stored in a cool place so that it is not affected by the heat produced by the computer.

There are so many discrepancies all over the web.

This says that Liion batteries should be charged "early and often," and yet we have many sources saying that these 'cycles' are bad.

this says that 'deep cycles' are generally bad, but sometimes necessary to recalibrate the 'fuel gauge' (like what I did.

this says that when running a laptop on AC power for a long time, the battery should be removed, rather than leaving it in there.


So. The discrepancies arise at how Liion batteries should be charged - often and to what extent.

Agreement arises over 40/60% and cool storage, no excessive heat, taking the battery out when plugged in for a long time, avoid many deep discharges, avoid extreme temps.



-> Here's what I'm going to do from now on:

I'm going to fully charge my laptop battery at home. When I go to school, I'll use it on battery power until it gets down to ~15% then plug it in and recharge it until it's at 100%. When I get to 100%, I'll unplug it and keep using it on battery. If I find myself at home with it plugged in, I'll take the battery out once it's recharged.

At no point will I deep discharge or store it in a too-warm environment.



I think this'll help keep my battery in good condition.

slash000

So I got my new battery in, and fully charged it.

It's showing 8 hours of battery life remaining.


Now if I can just keep it that way.

Daedalus

elevature wrote: »

So what's better, leaving the battery in and the laptop plugged in all the time, or just to take the battery out?

Leaving your laptop plugged in without the battery can supposedly lead to power surges in poorly-designed laptops but I've never actually seen this happen.

edit: also note that it could be the charge sensor that's broken and not the battery, and sometimes a full discharge helps whack those back into shape. Firsthand experience there.

timster

I worked in tech support for years, and had dozens of users with laptops.

From this I can tell you three things.

1. The "road warriors" wore out batteries faster. Those who were at their desks almost all of the time (on AC, universally with the battery in) rarely had battery problems. From this I can tell you that the advice to NOT discharge the battery without need is correct.

2. A particular laptop (or sometimes model -- I'm looking at you, Thinkpad 600 series) would sometimes be defective, and eat battery after battery. Good luck getting the manufacturer to fix this sort of thing as it's difficult to prove that the laptop is the cause, and they prefer to ship out replacement batteries until the warranty is up (usually a year on the battery even if the laptop itself had a 3-year warranty).

3. It's not particularly uncommon for a battery to fail as you described, and often there seems to be no reason. I believe that these are mostly caused by defective batteries unless the same problem occurs repeatedly for the same laptop or user. People tended to blame themselves for some reason, so after a couple years my "education" speech became "there's nothing you did wrong, there's nothing you can do, some of these are just bad". All the battery voodoo out there -- everything from deep discharges to putting them in the freezer -- would never solve the problem on a long-term basis.

Hope this helps...

minor incident

timster wrote: »

I worked in tech support for years, and had dozens of users with laptops.

From this I can tell you three things.

1. The "road warriors" wore out batteries faster. Those who were at their desks almost all of the time (on AC, universally with the battery in) rarely had battery problems. From this I can tell you that the advice to NOT discharge the battery without need is correct.

2. A particular laptop (or sometimes model -- I'm looking at you, Thinkpad 600 series) would sometimes be defective, and eat battery after battery. Good luck getting the manufacturer to fix this sort of thing as it's difficult to prove that the laptop is the cause, and they prefer to ship out replacement batteries until the warranty is up (usually a year on the battery even if the laptop itself had a 3-year warranty).

3. It's not particularly uncommon for a battery to fail as you described, and often there seems to be no reason. I believe that these are mostly caused by defective batteries unless the same problem occurs repeatedly for the same laptop or user. People tended to blame themselves for some reason, so after a couple years my "education" speech became "there's nothing you did wrong, there's nothing you can do, some of these are just bad". All the battery voodoo out there -- everything from deep discharges to putting them in the freezer -- would never solve the problem on a long-term basis.

Hope this helps...

Listen to this man.

Gihgehls

I don't know if this has been said or not, but since the internal battery gauge can become uncalibrated, it is possible that the OS thinks it has less power than it really does, forcing the computer to shut off before it really needs to. This happens with my two-wheel non-tandem electric scooter sometimes.