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In the past few weeks, my macbook shuts down when the battery dies. The battery does not even die at 0%, sometimes it shuts down at 5% or 10% remaining. I tried calibrating the baterry following this website: But it does not really help. I regularly use battery in my macbook, I'd say I use around 2-3 cycles a week.

My charge cycles is 440 cycles, and my current battery capacity is 3400mAh from the original 4100mAh. I have 2008 unibody Macbook. Does anyone know how to make it goes to sleep before the battery's dead?


The OS seems the think that the battery is ok...

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It may be time for a new battery. If the calibration didn't work, then logic dictates the software will not be able to detect the battery state, in order to prevent data loss, by going to sleep. – user3463 Feb 3 '11 at 5:51
Hmmm the OS doesn't seem to think so though. I attached a screnshot – Enrico Susatyo Feb 3 '11 at 6:10
up vote 0 down vote accepted

How long have you had your battery? I found that, depending on how hard your CPU works your battery, the lifespan of a battery can be as short as 18-24 months, with decreases in capacity as quickly as 1 year.

(NOTE: This is not normal, in the case of the Macbook I am talking about, it was stuck running a lot of CPU hogging Java and Flash environments. It also was fully charged and discharged 2-3 times per day, 5 days a week.)

But I have seen my system, when the CPU is getting pounded, going from 20% to losing power (and failing to sleep) on my older, extremely over-used battery.

I have a white Macbook, in case you wonder what battery I am using.

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Had it for almost 3 years. I'm aware it has around 2 years of lifespan. I guess I'll keep using this laptop for a little more then just replace it with a new one later... – Enrico Susatyo Mar 29 '11 at 10:26
Yeah. I don't know if its possible, but I'd like the OS to log the battery level periodically, and then on reboot compare the last logged level to the output of "last", to see if the threshold needs to be increased to avoid brownout. – benc Mar 31 '11 at 5:55
You can use coconut battery for the logging, but I don't think the OS can prevent brownout. – Enrico Susatyo Apr 1 '11 at 4:49

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