Computer battery help.

[gezza123]

Hi Guys.
Just a little guidance required please.

I have a Dell laptop, all in good condition exept for the battery, so I have just now purchased a new one, I dont know anything about this type of battery, and this is the first time I have ever had to use one.

This is what it tells me to do.
This is a Rechargeable Li-ion Battery
(1) charge the battery fully. done
(2) discharge the battery fully. done
(3) charge the battery fully. done
(4) discharge the battery fully. done
(5) recharge the battery fully, done
(6) The battery should be recharged as the above circle more than once per month.
The battery is now in the laptop and working ok.

My question is, do I have to do the above (charge/discharge) every month for this type off battery. thanks in advance Gezza123

[HamishBoxer]

Sounds a bit odd, normally if rechargeable then the equipment should charge it. I.E The Philips TV's with NiCad memory backup.

Sounds OK to me, smart LiOn batteries have a chip in them to monitor the charge, a full charge disscharge cycle 'resets' it (this one seems to need two). Worth doing so the on screen charge level is about right. This has nothing to do with the cells chemistry.

[paulsherwin]

I never bother doing this deep discharge stuff with lithium batteries and have never had any problems. I've had a Bosch cordless screwdriver for about 10 years which just sits in its charging cradle most of the time, and the battery still holds a full charge. My mobile phone is 3 years old and the battery lasts as long as it ever did.

Laptop batteries seem to throw in the towel after about 4 years whatever you do with them.

[gezza123]

Thanks Guys,
Battery now showing 100% on screen with last charge.
The battery icon on screen shows 4.3 hours left, so I will let it run with a dvd
on repeat and see how long it really lasts.

As I could not grasp why I have to keep discharge/recharging every month,
so I will leave it on mains untill I need to take it outside or to the workshop.

As Merlinmaxwell said it has got a chip inside to monitor its charge, so I have
opened up the old one, and yes there is a chip and some surface mounts on
a board, and two off the six batteries have gone black and showing no
charge.

I have now got the user manual for the (laptop inspiron 1501) and Dell advise
to leave the charger plugged in at all times untill you need to use it away
from a power line input, as this will not hurt/damage the battery,and should last at least 3 years,cheers Paul.
Thanks again Guys for the help and input. Gezza123

[SteveSmit]

The circuitry isn't just there to give you a semi-accurate reading of the capacity, it's there to take care of the battery itself. Lithium-ion is notoriously finicky. It has to be charged properly, discharged properly, not be allowed to completely flatten and just generally taken care of otherwise you can have impressive failures to say the least. It sounds like you were lucky with those two blackened cells. Lithium ion failures as often as not involve smoke.

As someone has said that discharging and charging ritual has nothing to do with the battery chemistry, it's getting that nanny circuitry calibrated. It has to know the characteristics of the battery pack so it knows where the limits are of the safe band of operation for the cells. Otherwise the circuitry will shut down the battery early.

However, normally, for most rechargeable batteries, doing unnecessary charge/discharge cycles (i.e. ones that aren't as a result you using the device normally) are just using up cycles. Every battery only has so many, and most will die faster with deep cycles than partial.

Adding something else into the mix, the Lithium-ion chemistry has a lifespan whether or not you use it. This lifespan business is why buying a spare li-ion pack is a waste of time. Assuming you don't kill your first one early from using its cycles up, the spare will be as dead as the original due to internal oxidization of the chemicals by the time you come to use it. Four years is generally doing pretty well for a lithium ion pack. That's four years after manufacture, not four years after you buy.

The only reason that isn't as big a deal as you might expect is that the average device that uses lithium ion batteries nowadays, mobile phones, laptops and the like are rendered obsolete and upgraded within that magic period. I bet everyone here knows at least one person though who has had a laptop that they had to keep tethered to a wall socket because the battery pack gives them a couple of minutes at most. Welcome to lithium-ion lifespan. The worst part about that is if your laptop is old enough, the manufacturer won't be making packs any more, so any you will buy (which will have to be new old stock) will already be aged at least to a degree. That for some devices leaves you with two options. Either leave it plugged in, or buy bare li-ion cells and re-cell your existing battery. That has the potential for big fireworks though if you get it wrong.

Sorry for post-zilla, there.

[SiriusHardware]

There is also the option of newly manufactured third party replica battery packs - a bit of a minefield in terms of quality I agree, but likely to be made more recently than the ones the original manufacturer has stopped making.

This is the reason I have never upgraded my 20-year old Amateur handheld radio - I bought it with a couple of AA cell battery boxes as backup for the sealed Nicad battery packs which died more than ten years ago. I have been able to keep it going using standard rechargeable AA batteries which currently have three times the capacity that the original packs did anyway, and will try to keep it going almost indefinitely now.

If I bought a modern handheld, it would almost certainly use proprietary Li-Ion cells which would not respond well to my pattern of use (2-3 days at a time about 3 times a year). And then when new Li-Ion batteries for it ceased to exist it would be relegated to shack use running on a DC supply.

I won't be a fan of Li-Ion power until the industry adopts a set of standard sized / shaped packs for more or less everything (unlikely, as they would prefer to be able to force you to stop using your product once it has exceeded what they consider to be its 'lifetime').

[SteveSmit]

There is also the option of newly manufactured third party replica battery packs - a bit of a minefield in terms of quality I agree, but likely to be made more recently than the ones the original manufacturer has stopped making.

Ah yeah I'd forgotten about that option. That can be a good solution as long as you're buying from somewhere reputable enough that you can have reasonable confidence their stock isn't being dug from the back of a shelf festooned in dust and cobwebs.

If I bought a modern handheld, it would almost certainly use proprietary Li-Ion cells

An unfortunate consequence of the fact that li-ion as far as battery chemistries go at least, does have very good energy density, even if it has a whole host of other cons.

Reminds me a bit of the megapixel race with consumer digicams. Never mind the fact that the individual photosites are smaller, giving the whole sensor more grain, when we can put a bigger number on the box!

I think even if they did release standard-ish packs, canny manufacturers would just build the battery into the device, and not make it immediately removable. That alone would put most people off trying to replace it themselves. Sony went that route with the Xperia S, though it was clearly a last-minute decision. Only that would explain it having a rear cover that covers the whole back of the phone, and yet under it, the only removable bit is the diddy SIM card with a big expanse of not a lot else.

[Paulus.d]

My old laptop, a fujitsu seimens LI-1705 had a battery that lasted 55 minutes and a slip of paper saying that if I want a better one send £70 to.....

It died after 8 months because I left it and used it constantly on power supply...

Regards Paul

[SteveSmit]

It died after 8 months because I left it and used it constantly on power supply...

The battery or the laptop?

If the battery, that won't have been to do with leaving it on the power supply, unless the power supply was badly designed and was gradually toasting the battery. If the battery was already down to less than an hour on a full charge, it was well on its way to the usual lifespan related death that all lithium-ion batteries eventually suffer. Another 8 months on top would easily have reduced it to being basically useless. A new lithium ion battery would be dead a lot faster if it was constantly cycled though.

If it was the laptop dying (and definitely not the power supply - did you try changing it?), then it goes with my experience of Fujitsu-Siemens laptops unfortunately. I've not found a decent one yet.

[MrElectronicman]

I have a DELL XPS laptop which was bought 7 years ago, the power pack has been almost constantly connected to mains since that time, and when I occasionally use it on the battery it will still last for more than 2 hours.

[SteveSmit]

It sounds like you've been uncommonly fortunate then.

[MrElectronicman]

It certainly does, from what I have been reading about laptop batteries.

In fact I have never had any problems with this beastie, he says with fingers crossed.

[SteveSmit]

I know some laptop batteries were NiCD, but I reckon that would require going back considerably further than seven years. Still it works, that's all that matters right?

[Maarten]

My Li-ion equipped HP of also 7 years old is used mostly on mains as well but will happily last 2 hours on a charge.

Fully discharging such a battery each month, will probably have a limiting influence on its life span.

[jjl]

Originally Posted by SteveSmit

I know some laptop batteries were NiCD, but I reckon that would require going back considerably further than seven years. Still it works, that's all that matters right?

Quite a long way back. The Toshiba laptop I bought in 1996 had a NiMH battery. Li ion has been in use for laptops since about 1999.

John

[ricard]

Apparently one things that kills Li-ion batteries is having them charged fully, not the actual charging process, which is why some recommend that you only charge them to 70 or 80% if you don't need to the maximum time from the battery. The chemistry is different from NiCd and NiMH, hence differing recommendations for charging.

There's a host of info available on the web if you care to look for it, problem is (as usual) weeding out the good from the bad ...

(On my Thinkpad I've set it up so that the battery charges to 85% and then stops, and doesn't start charging again until it comes down to 20%. I seldom use it for that long a time on the battery, so this charging setup works fine for me. My wife's Mac has no battery settings, it basically charges it to full if it drops below 95% or so. That battery basically died after about two years, had about 10 minutes left in it at that point, even though the battery monitor showed it was fully charged, and all the stats pointed to it having at least half the original capacity. New one purchased, problem solved, so it was definitely the battery.)

[Alvin]

Originally Posted by SteveSmit

If it was the laptop dying (and definitely not the power supply - did you try changing it?), then it goes with my experience of Fujitsu-Siemens laptops unfortunately. I've not found a decent one yet.

My Fujitsu-Siemens Amilo Si 1520 bought new 6 or 7 years ago has been brilliant and with its 2GHz core duo processor plus 2GHz ram (upgraded from the original 1GHz) it still holds its head high in present day company. Apart from replacing the battery a couple of times with Chinese copies (which have been fine) the only part needing attention was a noisy fan about 3 years ago.



Alvin

[Maarten]

My ancient HP Presario M2000 is still working fine on its original battery. It is mostly connected to the mains so there is very little cycling but the battery is indeed kept at 100% charge. I'm sure the capacity is lower than it used to be, but it can still run for almost 2 hours.

[SteveSmit]

My Fujitsu-Siemens Amilo Si 1520 bought new 6 or 7 years ago has been brilliant and with its 2GHz core duo processor plus 2GHz ram (upgraded from the original 1GHz) it still holds its head high in present day company. Apart from replacing the battery a couple of times with Chinese copies (which have been fine) the only part needing attention was a noisy fan about 3 years ago.

I don't doubt it, I'm just going on my personal experience with them, that's all.