How long do Laptop batteries generally last ?

[Behemoth]

It's been about a month since I last used my laptop, when I put it away in its bag I knew that its battery was pretty much flat. Anyway I booted up to see that Windows said "Plugged in, Charging 0%"

I left the laptop on for an hour or so, came back to it and the battery was still not charged, still said what it did above.

As I have a spare battery its no big deal, but I'm just wondering what the average life span of a battery is for a laptop, as I've had mine now for almost 2 years (HP G70 120EA) and I'm pretty sure the battery thats died is the one it came with.

The spare one I have was given to me from my old work when they were clearing out the empty laptop boxes as we had a laptop like mine stolen off display.

[HSK]

the one from my sony fz11z lasted about 2 / 2 and a half years, annoying coz I can't get an original battery now , wonder if a ebay one from china will be alright? That's the only thing putting me off, it blowing up etc...lol. :-/

*edit

My one actually doesn't even register any more, and a stop sign / cross through the battery icon in the notification area.

[GoNz0]

got one heading for its 6th year and still holds an hours charge

[watercooled]

How long do Laptop batteries generally last ?

Phew, that's not an easy one to answer - even if they're treated well or go unused, Li-ion batteries degrade over time, usually a fair few years but heat and abuse severely reduces this. Laptops get very hot and this kills batteries, as does keeping them fully charged all the time. I'm talking the difference between taking 4% off over a year to 40% in 3 months when being baked in a laptop. Discharging them to 0 also wears out Li-ion batteries faster, unfortunately people tend to stick to habits they learned with Ni-Cd batteries i.e. running down completely before recharging. And what doesn't help is salesmen and even product manuals still telling people to do it (the same applies to the recommendation to leave a phone on charge for 14 hours or so the first charge - it's complete rubbish, either it will take the battery to the max which harms them or more likely the charging circuit just cuts off when your phone says battery full - either way it's outdated advice).
Aaanyway, what I think has happened in your case is this - the battery has been in the laptop, slowly being drained by the computer which has taken it down to the first cutoff point. I.e. the circuit will not let any more power to be taken from the battery but if it's left on charge for a few hours it may be OK. If it's not in great condition, however, self-discharge has probably taken it below the minimum safe voltage. If Li-ion batteries fall below a certain voltage it becomes very dangerous to charge them again (i.e. they can explode or vent with flames) so as a precaution the protection IC will have permanently disconnected the battery. It's sometimes possible to get batteries in this state to charge again with a special charger but it carries a big risk and if the cells have reached this state and still manage to safely hold a charge, it would probably power a laptop for all of 2 minutes.
On the other hand, the circuitry in the battery could have just failed or a solder joint may have broken...
Hope that answers your question.

[jackvdbuk]

Long Post

good post, thank you


so leaving my desire fully charged charging through the night is majorly bad?

would chinese batteries be a bad move (first post asked aswell) for any device? or would only genuine usually expensive batteries for products only do?



my dell XPS M1530 battery is still going strong, holds its charge well which im glad it does.. batteries are expensive!

[Caesium]

good post, thank you
would chinese batteries be a bad move (first post asked aswell) for any device? or would only genuine usually expensive batteries for products only do?

Be very wary of Ebay sourced batteries and the like - a chap on maemo.org (N900) forums bought dozens of them specifically with the aim of testing them and discovered that what was advertised as a 1300mAh battery was actually anything from 320mAh to 1300mAh, there's just no way to tell until you take delivery and see how long it lasts.

http://talk.maemo.org/showthread.php?t=65568

[watercooled]

good post, thank you


so leaving my desire fully charged charging through the night is majorly bad?

would chinese batteries be a bad move (first post asked aswell) for any device? or would only genuine usually expensive batteries for products only do?



my dell XPS M1530 battery is still going strong, holds its charge well which im glad it does.. batteries are expensive!

No, it's not necessarily bad - it should cut off charging as soon as the battery is full and phones don't get nearly as hot as laptops do, heat does much more damage than charge state. Just keep in mind it's really not necessary to do any sort of maintenance on Li-ion batteries, in fact they prefer partial charges and discharges. Running them down once in a while helps calibrate the battery meter in some devices but doesn't do anything for the battery. It's a shame device manufacturers set the cut-off points for runtime (for marketing, I suppose) rather than protecting the battery more, they could shave like 10% off the runtime and make the pack last a heck of a lot longer. I did a quick test on the battery in my phone and it takes the battery pretty much to the limits on both charge and discharge. It's probably also due to the fact most people my age tend to go through several phones a year so battery lifetime isn't very important. Despite being very much into computers and whatnot I've had the same phone (Nokia 6131) for years and I'm very happy with it. Plus, I'm really not into touchscreens! So, for people like me you might end up having to change the battery a few times throughout the phone's lifetime.

Chinese batteries: Hmm, that's not easy to answer. I suppose quality can vary massively between batteries so it would be pot luck really. Worst case scenario, they could be dangerous if they don't contain properly functioning protection circuitry or not quite as bad, they might just be a bit crap like Caesium says. Genuine ones are overpriced though but there's often no better solution since batteries tend to be proprietary.

[circuitmonkey]

As mentioned in previous posts, I've replaced my dead original battery with a Chinese replacement and everything is going very well, couldn't be happier.

I used http://www.365peak.com/

The other alternative is to look at just replacing the battery cells, if the charging circuit is still working.

[watercooled]

The other alternative is to look at just replacing the battery cells, if the charging circuit is still working.

This, but only if you're competent with electronics, soldering and know the dangers of working with Li-ion batteries. Connect an unprotected cell the wrong way and BOOM. It is a good solution though and should work out much cheaper than the official replacement.

[Behemoth]

Thanks for the info gents, it kinda confirmed what I knew already, just wanted to be sure before I go making a berk of myself to Currys where I got the laptop from to see if they can give me a new battery for it.

If it was a £50 job I'd be happy to buy another, as batteries for my Laptop are approx £100 I'm not too happy to pay that kind of money.