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sir_hc · Oct 18, 2005, 03:28 PM

I just bought my wife an iBook which she uses sitting in front of the TV. I know Apple don't recommend keeping it plugged into the mains for prolonged periods but will this actually harm the battery?

Since she doesn't take the iBook outside a 10ft radius from the sofa I don't see the point in using up battery cycles when it can use the mains. I don't have much experience using things with rechargeable batteries and don't really know what's best in the long term. I do unplug it and cycle the battery once in a while though. What do you guys think?

Dave N · Oct 18, 2005, 11:30 PM

Apple recommends cycling the battery at least once per month.
http://www.apple.com/batteries/notebooks.html

My iBook is 3 years old and I didn't know about cycling the battery until a few months ago. I ran mine off the mains all the time (for about 2.5 years) and now the battery won't hold a charge. It gets down to about 75-80% charge and gives me warnings that it needs to hibernate because there isn't enough power to keep running, or it just puts itself to sleep unexpectedly.

vinster · Oct 19, 2005, 12:13 AM

Thanks for posting this. I have a 7-month old powerbook and only cycled the battery twice. Hope I haven't reduced its capacity.

Flip500 · Oct 19, 2005, 05:44 AM

Wait, i don't get it, what is cycling your battery and how do you do it? I couldn't really find it off that link...

nJm · Oct 19, 2005, 06:03 AM

You use the iBook from full battery until it has to shut itself down, then charge it up to 100% again.

I didn't do it that often and now my 16 month old iBook only lasts 1hour 40 minutes (when I got it it was around 5 hours)

cmeisenzahl · Oct 19, 2005, 07:18 AM

I would let it fully (or close) discharge maybe every month or two at most.

Chris

tooki · Oct 20, 2005, 03:13 PM

I actually got really good life from my Pismo batteries by using them daily. LiIon batteries seem to hate sitting idle. A friend of mine ruined a TiBook battery by never using it. After one year, a "full" charge gave 15 minutes (!!!) total run time.

I'd actually exercise the battery once a week.

tooki

tooki · Oct 20, 2005, 03:14 PM

Oh, and if you have a spare battery, charge it to 40% and keep it in the fridge (just above freezing).

tooki

Cucucachoo · Oct 20, 2005, 08:12 PM

I follow the same rule with my iB that I do with my mobile phone and iPod. I only charge it if the battery is at least below a 49% charge. This is because if your going to use a charge cycle you might as well make it count. I have had this same battery for a while now and it get about a 3.5 - 4 hour charge out of it depending on the settings and running programs.

Use the battery. Thats what its there for.

teney7 · Oct 20, 2005, 09:24 PM

Does it matter at all how fast you run down the battery to cycle it...? For the sake of just running it down if when I am at home, it would have about two hours max seeing as I run AirPort, BT, full brightness, and about 10 programs all at the same time...

cmeisenzahl · Oct 21, 2005, 08:26 AM

I've noticed that even a modest amount of screen dimming helps with battery usage quite a bit.

Chris

Simon · Oct 21, 2005, 09:42 AM

Using batteries is great. Yippie. Whatever.

But, you can't if you use closed-lid mode! As soon as you unplug the charger, the PowerBook will go to sleep.

Dork. · Oct 21, 2005, 11:57 AM

Originally Posted by Dave N

I ran mine off the mains all the time (for about 2.5 years) and now the battery won't hold a charge. It gets down to about 75-80% charge and gives me warnings that it needs to hibernate because there isn't enough power to keep running, or it just puts itself to sleep unexpectedly.

This happened with my wife's PB. One of the cells (out of four connected in serial) in your battery pack is in the process of dying. The charge measurement reflects the total amount of charge in the battery, but since one of your cells is bad, when it cuts out the entire serial battery chain can't keep up the voltage necessary for proper operation, and the power management software puts the computer to sleep.

Unfortunately you won't ever get your full battery life again out of this battery, and you'll be in the market for a new one soon.

My iBook, which was bought at the same time, but which was power-cycled more times, still holds a decent charge.

Dave N · Oct 21, 2005, 04:28 PM

Originally Posted by Dork.

This happened with my wife's PB. One of the cells (out of four connected in serial) in your battery pack is in the process of dying. The charge measurement reflects the total amount of charge in the battery, but since one of your cells is bad, when it cuts out the entire serial battery chain can't keep up the voltage necessary for proper operation, and the power management software puts the computer to sleep.

Unfortunately you won't ever get your full battery life again out of this battery, and you'll be in the market for a new one soon.

My iBook, which was bought at the same time, but which was power-cycled more times, still holds a decent charge.

Thanks for the explanation. I always wondered how it could register an adequate charge one minute, then shut down the next.

erniesthings · Oct 21, 2005, 09:29 PM

Is there anything that can be done to bring a battery back to life. I've been using my ibook probabley plugged in about 90% of the time. It's about 2 years old an just this week it's won't hold a charge for longer than20 mins.

Am I in the market for a new battery or can I bring some life back into this one.

Thanks

Ernie

Dork. · Oct 21, 2005, 10:46 PM

Originally Posted by erniesthings

Is there anything that can be done to bring a battery back to life. I've been using my ibook probabley plugged in about 90% of the time. It's about 2 years old an just this week it's won't hold a charge for longer than20 mins.

Am I in the market for a new battery or can I bring some life back into this one.

Thanks

Ernie

nope, all you can do is buy a new battery at this point. The people at www.batteryrefill.com claim to be able to replace the cells in your battery with new cells, cheaper than buying new but still pricey. Maybe when my iBook battery finally bites it I'll give them a try.

erniesthings · Oct 22, 2005, 07:56 AM

Would you recommend buying an apple brand battery or is there a better/cheaper third party battery that's available.

Thanks again

stu1234 · Oct 25, 2005, 10:35 AM

should i plug in the computer when the warning comes on and it goes to sleep?
Or should i let the battery die while its asleep? Is it harmful to run it to 0 power?

hey dont u think apple should develope a charger that can regulate its self for when an ibook is permantly pluged in

thanks for all the help so far.

Simon · Oct 26, 2005, 02:03 AM

When you cycle the battery, you don't plug in the charger when the warning pops up. You let the battery run down until the iBook goes to sleep. After that it won't wake up till you plug in the charger. Once you've plugged in the charger you let it charge till the battery indicator says it's fully charged. At that point you've successfully cycled the battery and re-calibrated the power monitoring.