Battery acting strangely

jwink3101 · April 21, 2005 8:54AM

After having to reset the PRAM and PMU in trying to fix another problem (Which it didn't fix. Long story) my battery has been acting very strangely.

It discharges very quickly and it estimates a very little bit of time left. Then it drops from 20% to zero right away. When i then move to a place near a plug and plug it in, it starts recharging but it estimates a little bit of time until charged (for example, it went from zero to 20% in about 15 minutes).

Any help would be appreciated

ebby · April 21, 2005 12:42PM

It sounds like one of the cells (or more) died in your battery. Charge it all night if you haven't and see what it reads. If it is less than an hour, check your warrantee or it is time to get a replacement.

jwink3101 · April 21, 2005 2:53PM

So resetting all that stuff had nothing to do with it? Anyway, when you say to see what it reads do you mean its estimated time left

ebby · April 21, 2005 3:54PM

Yea, estimated time. I don't know how old your battery is, but usually when there is a sudden drop in performance, it is dying.

jwink3101 · April 21, 2005 4:00PM

It is a little over a year but i use it hard. I often end up using it at school until it either dies or some days by the end it will be 20%,. I also then charge it sparsatically (i.e. 20 minutes here, 40 there, etc).

Would that do it in a year?

ebby · April 21, 2005 4:20PM

Frequently discharging the battery completely is not so good. You do that once to calibrate a computer chip in the battery, but I rarely drain it 100%. I use my battery about 50% a day and charge it all night. Sometimes when I have less than an hour left, I plug it in and start charging it while working. (If I'm near an outlet.) My first battery lasted 4 years and this new one (almost 1 1/2 years old) still has 5 hours of use per charge. (I still use a 400Mhz Pismo) 8)

jwink3101 · April 21, 2005 5:01PM

Sadly, i have no choice in the matter. I need to use my computer all day and i can only charge it during certain periods or at times during lunch.

Still, is it just coincidence that the batter has dropped to this level around the same time i did all of those resets?

ebby · April 21, 2005 5:08PM

my only suggestion is to reset the PMU, fully charge the battery (10 hours I think) then fully discharge the battery without sleeping/shutting down. If the computer chip in the battery is miscalibrated, this should fix it. Otherwise, you should look into getting a new battery. Maybe two if you really use them that much.

EDIT: Some manufactures build special higher-capacity batteries than the standard Apple brand. It may be worthwhile to look into one of those.

jwink3101 · April 27, 2005 5:15PM

I haven't gotten time to try the PMU agian but i found a program called Battrox 1.8 that tells me the capacity

It says i have 2.2 aH capacity and 256 charge cycle.( According to apple, the charge cycle is when you use the full batteries power. Even if you use to 50%, charge and do it agian, you used one cycle but never dropped below 50%)

Anyway, IIRC, i read that ~4 aH is normal (i do not know where) and 256 seems low for my battery be be at half-capacity

What do you think

ichiban_jay · April 28, 2005 12:19AM

yeah, my batt has the same problem. When I called applecare they said the batt is over a year old and since it is counted as a consumable they can't replace it.

This angered me cuz my batt has had this problem for 6 months now, but I had been complaining with the apple store! so now it seems that if I had called instead of going to the store they would have replaced it.

I emailed steve jobs sunday and now his secretary called me, I have to call her back to talk about it.

Wishing for the best!

ebby · April 28, 2005 12:54AM

Here in California if you report a problem when the computer is under warrantee you can still get it repaired after it expires. I had that happen with my iPod, where I sent it in to have it fixed and it was returned with the same problem. I had to return it again for the same problem but the warrantee expired. If they have a record of your problem, they my still repair it.

maccrazy · April 28, 2005 6:35AM

Quote:

Originally posted by Ichiban_jay

yeah, my batt has the same problem. When I called applecare they said the batt is over a year old and since it is counted as a consumable they can't replace it.

This angered me cuz my batt has had this problem for 6 months now, but I had been complaining with the apple store! so now it seems that if I had called instead of going to the store they would have replaced it.

I emailed steve jobs sunday and now his secretary called me, I have to call her back to talk about it.

Wishing for the best!

Is the battery not covered under the extended warranty - that's one of the reasons to get one isn't it?

jwink3101 · April 28, 2005 6:47AM

I also used

Code:

ioreg -l -w0 | grep Capacity

and got the same numbers i mentioned above but times 1000 (makes sense becuase of the units).

The provblem is, i did a deep cycle yesterday and the number dropped 147 or so. That is a LOT for a deep cycle. Will a new batter fix this? Thansk

uozyilmaz · July 4, 2005 5:23PM

here is a simple apple script to log your battery data when you start system. And predict when will your battery die

http://web.adu.edu.tr/akademik/uozyilmaz/batteryexpire/

ebby · July 4, 2005 5:58PM

Sweet!

I didn't think a dying battery was so linear. (And therefore easily predictable.)

uozyilmaz · July 4, 2005 6:09PM

Quote:

Originally posted by Ebby

Sweet!

I didn't think a dying battery was so linear. (And therefore easily predictable.)

i think so,

i hope, it will be prabolic (^2) or logaritmic

\

because of treads about battery problems, many battery die suddenly rather than step by step

actualty to many factor affect this thesis

- irregular battery usage

- changing OS or new updates

etc.

my system is collecting data now.

we will see what happen?

thanx

Battery acting strangely

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