Laptop battery

[Brewster Buffalo]

Laptop (Packard Bell) about 18 months old and only recently gone wireless. Until then used the mains adaptor with the battery in.

On battery recently when got the low power warning suddenly despite the showing nearly full power left. Since then haven't been able to get about more than 40% capacity on the battery even after 12 hours charge..

Questions..

Does this indicate the battery needs replacement??.and

Does using the AC adaptor and leaving the battery in (full charged) cause any harm to the battery??

[Lancelot37]

1. Yes, I'd say that you need a new battery. (They are expensive!)
2. No I don't think that leaving the battery in and on charge has any detrimental affect.

Experience with my last three Laptops has been that 3 years is the maximum battery life experienced.

My current Dell laptop shows a fully charged battery. In use it lasts for less than 25 minutes and then collapses suddenly, shutting the computer down. The Laptop is less than three years old.

[Background Noise]

My experience is exactly that - had it plugged in all the time and the battery became useless - but it was a P4 which is a bit power hungry I think. Present one is a core duo and I run it on the battery until its flat then plug it in to charge it up - so far so good.

[BEagle]

I managed to source a couple of new batteries for my trusty Dell Latitude x200 recently. With them came clear instructions that the batteries must be 'conditioned' with several full charge/discharge cycles when first used.

So I did that - and the battery now keeps going for over 2 hours whereas the old one died after about 15 minutes after being disconnected from the charger.

A good idea to do a complete charge/discharge/charge every week, I reckon.

[green granite]

Agree with Beagle on that batteries always last longer and produce more power if they are deep cycled regularly. You might improve the condition of the old battery by discharging a large value capacitor through it at twice the battery volts, it clears shorting whiskers from the plates, or you might kill it totally.

[Brewster Buffalo]

Thanks for advice...

BB

[slim_slag]

If you've got a Li-ion battery, which is likely, you shouldn't be discharging it fully. If they go totally flat it messes them up. They have a fixed lifespan which starts ticking from the time of manufacture and like most things chemical is dependent on temperature. So keep them cool and if you don't use them for a long time then give them a quick charge every now and then.

[Binoculars]

There are lots of ripoffs in the computer world, but laptop batteries take a bit of beating. Disgraceful. Mumble, grump, mutter whinge rhubarb rhubarb.....

[Brewster Buffalo]

Thinking about this a bit more I could have extended battery life by removing it when using the mains adaptor (assuming it was fully charged) as that would reduce the number of unecessary charges..

[preset]

I agree with BB. Have read that computer batteries have a limited number of cycles in their lives. Leaving a battery in the computer on mains does lead to cycling albeit small. Taking the battery out of the computer fully charged while on mains may increase the life.

[Keef]

The critical factor with Li-Ion is, as slim-slag says, total time since manufacture. Don't buy a new one till your old one is on the way home, and then ask for the date of manufacture before you pay over your hard-earned.

I don't think Li-Ion care much about number of cycles - mine does 45 minutes in the laptop, and always has, despite the manufacturer's quoted "up to 2 hours". It shows 2 hours to go at switch-on, counts down logically to about 1 hour 15, then beeps its emergency power-down and shuts off.

I have a mains power supply and a car power supply (also works in the aeroplane) - belt and braces, but serves me well.

[BombayDuck]

Binos - I think the laptop battery scam is beaten by the printing ink scam...

[HuntandFish]

Best treatment varies with type of battery .
Newish laptops should have lion more capacity for a given weight than their perdecessor NI Mh .
If abused when recharging Lion batteries can burst into flames . I use them for model electric Helicopters . Fantastic performance compared with the Nicd I used some years ago for electric flight