Laptops Be cautious leaving laptops unattended while charging

[Gryph0n]

I've read many reports of laptop batteries exploding, but I would usually think "It wouldn't happen to me". On at least one ocassion, I have myself been guilty of leaving the laptop for charging while going out. However an incident just happened yesterday that should make me far more cautious in the future.

Just yesterday, in one of the apartments in my complex, a couple left the laptop on sofa, with the charger on, and went out. While they were out, apparently the laptop melted/exploded, and caused a fire that burnt down the sofa and other furniture in the living room and threatened to explode the LPG cylinder in the kitchen.

Luckily the fire alarm went off, and the Fire Brigade dispatched 2 fire engines. The Fire Brigade was able to put out the fire before it became an inferno.

I wonder what it is with the chemistry of laptop batteries (typically Lithion-Ion nowadays) that makes them explode. On the other hand, haven't heard about UPS batteries (typically sealed lead acid) exploding.

A common thread I've noticed with these incidents is the batteries seemed to be fully charged, and were being fed either a trickle charge from the charger, or getting overcharged.

 

[mav2000]

Place a laptop on a sofa and you have basically closed the vents that allow airflow. Then with battery charging added to the mix, you will get high temps and buring of plastic around the heated areas, which causes a chain reaction.

 

[Vasishta.Sushant]

^^^
Thats very much the reason. Nothing to do with just the charging.

 

[quixand]

Glad to hear a major accident was averted. Something similar happened at a colleague's place in the US w/ a LOT of damage.

I started powering off all electronic devices last year. PC/Consoles/TVs everything. Save Energy, Have a proper night's sleep (many a times have I fallen asleep w/ TV/PC on). My SII sometimes gets so hot while charging I'm afraid it will cause some issue someday.

China zindabad!

 

[Gryph0n]

Place a laptop on a sofa and you have basically closed the vents that allow airflow. Then with battery charging added to the mix, you will get high temps and buring of plastic around the heated areas, which causes a chain reaction.

^^^
Thats very much the reason. Nothing to do with just the charging.

Face-palm. I didn't think about the heat factor at all; I was thinking solely from perspective of battery chemistry.

But again, you'd hardly hear about such incidents in the old days where Ni-Cd used to be the common battery chemistry. Ni-Cd had issues with 'memory charge', but meltdowns seem to have been rare. There seems to have been an increase of these incidents after the battery chemistry moved to Li-Ion.

 

[superunknown27]

Must be a chinese battery at fault

 

[ch@ts]

Face-palm. I didn't think about the heat factor at all; I was thinking solely from perspective of battery chemistry.

But again, you'd hardly hear about such incidents in the old days where Ni-Cd used to be the common battery chemistry. Ni-Cd had issues with 'memory charge', but meltdowns seem to have been rare. There seems to have been an increase of these incidents after the battery chemistry moved to Li-Ion.

You're right. I think the problems got more to do with how we're using the technology than with the chemistry itself.
We probably didn't hear about issues with the older Ni-Cd batteries because they weren't trying to make the batteries so powerful. Or the form factors of the phones/laptops and their batteries were larger before.
Li-ion batteries are more energy dense than ni-cads, and they're being used in thinner machines. Add to that the fact that people have given up reading manuals and warnings, and you've got a recipe for disaster.
The media's become a lot more aggressive too, so while news of a battery explosion 7 years ago may have been ignored, today it'll be shared on a million facebook walls, re-tweeted, and replayed a million times over.
Product life-cycles have become shorter, design and development times have reduced, and everything's outsourced.
It's a miracle we haven't had more explosions.

 

[ariendj]

not sure if it implies to all the laptops but my 3 year old dell studio goes into hibernate when it heats too much and i admit careless approach to using laptops like using on bed,sofa etc. should be avoided.
suggestions would be to use laptop cooler and cleaning the laptop fan once in 6 months.

 

[Gannu]

I sometimes wonder, despite the technology maturing by the day why cannot the battery charging in laptops and cellphones be cut-off after a desired percentage value set by the user say 85~90%. The maximum limit can be set from the BIOS (my netbook has the option) but not the charging.

 

[ayanavish]

Scary!! Have heard couple of such stories in Kolkata too, where the battery burnt the whole room down.

I have a query bit OT though. My Acer laptop's battery shows "it needs replacement" (Win 7). The battery doesn't give more than 20 minutes of running time. It has good ventilation as well as a good cooling pad underneath, keeping it cool. So, in such a scenario, does a depleted battery has more chance of exploding than a healthy one? Is it theoretically safe to run a laptop with depleted battery?

 

[babhishek]

battery depleted means, charges wont last, so from the safety angle it should be the safe.

but i'd feel safer with a newer battery

 

[Gryph0n]

not sure if it implies to all the laptops but my 3 year old dell studio goes into hibernate when it heats too much

I'm not sure whether this would also give you safety from a battery meltdown. My guess is that the heat sensors being used would be CPU, chipset Northbridge/Southbridge, and possibly GPU. I would think it unlikely that the battery is being monitored for heat.

With my Acer laptop, even in hibernate mode, the power led still glows if the charger is on. I would assume that the battery charging circuit is still on.

Scary!! Have heard couple of such stories in Kolkata too, where the battery burnt the whole room down.

I have a query bit OT though. My Acer laptop's battery shows "it needs replacement" (Win 7). The battery doesn't give more than 20 minutes of running time. It has good ventilation as well as a good cooling pad underneath, keeping it cool. So, in such a scenario, does a depleted battery has more chance of exploding than a healthy one? Is it theoretically safe to run a laptop with depleted battery?

You should check whether the battery has swollen. Typically, Li-Ion batteries have a limited lifetime (2 to 3 years), and then loose the ability to hold charge and can also swell up.

My Nokia N82 mobile uses a Li-Ion battery, and after 2 years the battery couldn't hold charge for a full day usage. More worrying, the battery also swelled up so much that the back cover started flexing and got too tight to open up. I stopped using the mobile till I was able to get a new battery.

Anyway, since you aren't getting much backup from the battery, why not remove it and run the laptop off a UPS? Or even better, get a new battery.

 

[JuGGa]

I sometimes wonder, despite the technology maturing by the day why cannot the battery charging in laptops and cellphones be cut-off after a desired percentage value set by the user say 85~90%. The maximum limit can be set from the BIOS (my netbook has the option) but not the charging.

You can always limit charging of battery in laptops.

I have a query bit OT though. My Acer laptop's battery shows "it needs replacement" (Win 7). The battery doesn't give more than 20 minutes of running time. It has good ventilation as well as a good cooling pad underneath, keeping it cool. So, in such a scenario, does a depleted battery has more chance of exploding than a healthy one? Is it theoretically safe to run a laptop with depleted battery?

Totally safe mate.

One thing I want to say, if you really want to run your laptop for long or something which stresses your laptop, remove the damn battery. Nothing will happen. Yesterday, my laptop was continuously on for 48 hrs on charging, and it went with breeze coz I know how to keep it.

 

[ayanavish]

Thanks Gryph0n and @JuGGa ! I was also planning to buy a UPS and remove the battery for safety. Will take a look for swelling once I am back home. That's a 3 year old laptop so, might as well sell that off in the next few months and buy a new one.
@JuGGa - only thing preventing me from removing the battery is the frequent power cuts. So, it might be a better idea to get a new UPS than a new battery.

 

[Gannu]

You can always limit charging of battery in laptops.

Read my previous post again. I mentioned limiting is possible but not to cut-off the charging once the battery is fully charged.

 

[JuGGa]

Read my previous post again. I mentioned limiting is possible but not to cut-off the charging once the battery is fully charged.

AFAIK modern chargers are self capable of cutting the charging after the charge is full.

 

[Gryph0n]

AFAIK modern chargers are self capable of cutting the charging after the charge is full.

I have a 2.5 year old Acer laptop, and I've never seen the charger cut off by itself.

But if your charger has an auto cutoff, I'd be interested in knowing the brand of your charger. Is it a 3rd party charger, or the default OEM ?

Now, usually chargers keep a trickle current going into the battery to prevent the battery from self draining (Rechargeable batteries lose some charge by themselves even when not used). So I'm also curious if you ever faced the scenario that battery wasn't at full charge after the auto cutoff kicked in.

 

[JuGGa]

I have a 2.5 year old Acer laptop, and I've never seen the charger cut off by itself.
But if your charger has an auto cutoff, I'd be interested in knowing the brand of your charger. Is it a 3rd party charger, or the default OEM ?
Now, usually chargers keep a trickle current going into the battery to prevent the battery from self draining (Rechargeable batteries lose some charge by themselves even when not used). So I'm also curious if you ever faced the scenario that battery wasn't at full charge after the auto cutoff kicked in.

Well if it wouldn't have been there, charger would get much hot, which it doesn't.
And how can you even know that charger has gone into auto cut off ?
I've never faced the last problem you said.
Also the self discharge about the li-ion batteries you said is a too slow process to observe manually. I leave my battery for 2-3 days, and it stays as it was.

 

[casper^]

I have a 2007 model compaq laptop but don't have a battery anymore and was about to buy one soon. But reading this thread I may buy a UPS instead. The only thing I'm worried is the backup time the UPS would provide. Would it be at par with a laptop battery?

Another solution I can use is that I already have a portable laptop inverter (the one used inside a car). I could get an Exide battery to power up the inverter and plug-in the laptop into the inverter. But I would need a separate charger to charge the Exide battery in this case. The inverter has about 180 Watts so it can also provide power to my broadband modem and Wi-Fi, but the UPS can do the same too I guess.

Which setup would be better?

 

[Gryph0n]

I have a 2007 model compaq laptop but don't have a battery anymore and was about to buy one soon. But reading this thread I may buy a UPS instead. The only thing I'm worried is the backup time the UPS would provide. Would it be at par with a laptop battery?

Another solution I can use is that I already have a portable laptop inverter (the one used inside a car). I could get an Exide battery to power up the inverter and plug-in the laptop into the inverter. But I would need a separate charger to charge the Exide battery in this case. The inverter has about 180 Watts so it can also provide power to my broadband modem and Wi-Fi, but the UPS can do the same too I guess.

Which setup would be better?

My understanding is that the switchover time of inverters is fine for electrical equipment, but it will cause a poweroff for computers. If you look at the Peripherals section, you'll find many people using UPS in conjunction with inverter to avoid this issue.

A standalone UPS would be the better option, unless you have very long powercuts that need the inverter too.