Sound like a Duff Battery?

[Bakey]

Hi there,

I've had my iBook G4 800 for a little over two years and all has been sound and dandy.

Over the last week or so I've noticed a rapid decline in battery life; it now averages around 30 to 40 minutes at best, and this is with "Better Battery Life" selected as default. Once the battery charge meter reader hits 26% it very quickly warns me that I'm running on reserve and it's gone!!

Does this sound like knackered cells and typical of a two year old battery? Or... are there any emerging issues with 10.4.4 and false battery readings??

Ta very much -- any advice or thoughts would be very much appreciated!!

 

[mad jew]

Have you calibrated the battery recently? Calibrating the battery means completely discharging it until it falls asleep and then completely charging it up again.

 

[Bakey]

Have you calibrated the battery recently? Calibrating the battery means completely discharging it until it falls asleep and then completely charging it up again.

Hi Mad Jew, within a minute or two of it hitting the "reserve power warning" it goes to sleep! So I'm kind of assuming it has already been calibrated as a result!?

If not, what would you recommend as a means of ensuring calibration has taken place before a complete re-charge?

Many thanks in advance...

 

[mad jew]

Well, to calibrate it you have to charge it until the little adaptor light goes green afterwards too, it's not just a matter of discharging it. I guess the next step is to reset the PMU.

 

[Bakey]

Well, bit of an update... I've reset the PMU, ran the iBook 'til it shut itself down and proceeded with a full re-charge [two or three times] -- and although the battery meter is now recommending some 74 minutes of remaining juice it still shuts down very rapidly when the meter hits around 30%.

But, having said this is does seem a little better!!

The iBook and battery are a little over 2 years old; I'm kinda guessing this is good old wear and tear!!

Thanks again...

 

[mad jew]

How terribly strange. I would have thought the PMU reset would either fix it or not, but I wouldn't have thought it'd half help. Maybe reset your PRAM, if only to pass the time. Actually, it might help.

Is there any way you could test this thing with a different iBook? Could you swap batteries with a friend or someone? It might help determine if it's a battery or computer problem (my guess is battery).

 

[Abstract]

Test it?

This is standard issue dead battery. This is how Li-Ion batteries work, whether you use it a lot or not. Calibrating it after every 20 times you use it on battery power would help, and charing it even when you have 41% battery life (just an example value) remaining is also good for the battery. You don't have to drain it down to 0% before recharging it. That's old skool stuff and current NiMH batteries. Li-Ions found in mobile phones, laptops, and digital cameras don't have this issue.

So...

Sound like a Duff Battery?

Oh yeah!!

 

[Bakey]

Thanks a lot for the advice chaps - I guess I'm going to have to resign to the fact that it's a "duffer"!

It's still doing the weird countdown to 29%/30% then dropping into sleep mode -- just as an after thought are batteries covered under AppleCare? [I know this thread is a little old and should be retired so I'll have a good look around with regards to this last question!]

Many thanks once again...