[X4U] Laptop battery life?

[Stroller]

Hey, gang,

I have a 13" MacBook, which I bought 15/06/2006. Since I ordered by  
phone from Apple I'd guess it may have arrived a week or two later.

Originally when the laptop was new the battery meter would read "4  
hours remaining" when fully charged and I would say I probably got at  
least 3.5 hours out of it. When it was new I would get a warning when  
there was 10 or 12 minutes remaining, and if I didn't save my work &  
connect to a charger then the laptop would go dead when 3 or 4  
minutes showed as remaining.

The above behaviour is just as I experienced with my previous 12"  
Powerbook G4, which I must've bought in 2004 and which I owned for 2  
or 2.5 years. The battery charge would give me about the same number  
of hours and it would warn me & cut out in exactly the same way with  
a few minutes remaining on the clock. I figured that even when I'd  
owned it all that time -  2 or 2.5 years - the battery life was not  
less than 75% or 80% of what it had been originally.

Around about May or June this year the graphics card in my G5 died  
and the MacBook started getting a little more use - perhaps 4 extra  
hours per day - and I was quickly annoyed to find that it was running  
out of charge & shutting down without warning. In July I logged a  
call to AppleCare to complain about this & they asked me to reset my  
PRAM, but my G5 was fixed shortly afterwards, so the matter became no  
longer so pressing.

Within a couple of weeks it became apparent, however, that the  
problem hadn't been resolved and by I'd estimate that by last month  
battery life was down to 2 hours or less. Last night the laptop cut  
out dead when it was displaying 25 minutes remaining.

So I called Apple about this this afternoon, and they tried to tell  
me that batteries wear out, deteriorate & that mine is within  
specification. What are the member's thoughts on this?

The short story is that after I expressed my dissatisfaction the  
support agent at Apple agreed to give me a new battery "as a  
courtesy". Based on a "full charge capacity (mAh)" of 4105 in System  
Profiler they reckoned the battery to be 80% as good as new, but that  
just doesn't jibe with the number of hours I seem to be getting out  
of it - unless I'm misunderestimating quite badly, I'm getting about  
half the battery life I originally did.

Part of the reason that Apple agreed to this replacement was that  
they started out by saying that one should only expect 300 charge  
cycles out of a battery and that mine has 302 (again, shown in System  
Profiler). I replied by observing that 50 or 100 of those must've  
been in the last 6 months since I first reported the problem and they  
said that I'd reported 302 charge cycles in July. Either their logs  
are wrong or the flash memory (??) inside this battery is knackered.  
I suppose that could cause the problem I'm seeing.

I'd better add that the usage of my Powerbook & my MacBook has been  
about the same - my laptop gets fully charged, and is then normally  
used for a day or two until it's flat and fully charged again.  
Sometimes it's charged up again when it's only halfway flat, but not  
so often. It probably averages three "charge cycles" (if I'm using  
that term correctly) per week, perhaps 3.5. The exception to this was  
indeed when my G5 was misbehaving, but again it was generally fully  
charged & discharged each time; I guess it may have racked up a  
maximum of 100 charge cycles over that 2 month period, but that's  
absolute tops. Obviously I don't think that's a big contributing  
factor, but perhaps I'm mistaken?

As I said to the AppleCare guy - I absolutely wouldn't be complaining  
if battery life was down to 75% or 80% of what it was originally -  
I'd consider that quite reasonable.

What I can offer to the list is that if you have problems with your  
battery then report them early. If AppleCare's staff starts to  
indicate that they reckon you should buy a new battery then you might  
nevertheless get a warranty replacement if you're polite & present  
your case well.

I'd love to hear the list's thoughts & experiences over laptop  
battery life in return. A bonus question: in System Profiler, under  
Power it says "first low level warning: no". Is this the setting that  
disables the battery from saying "yikes! I'm about to power down, so  
you should save your work"? And if so, how do I turn it on again,  
please? Apple didn't ask me a thing about this when I was on the  
phone to them today.

Thanks in advance for any comments or advice,

Stroller.