13" Battery not Calibrated

[mgartner0622]

Hello-

I have a Mid 2009 2.53GHz 13" MacBook Pro with the 1000 charge cycle battery.

Sometimes, I can only get at most 2 hours out of my battery after it's been calibrated numerous times. My percentage full drops like crazy, until my notebook goes into hibernation mode. If I plug it in, and boot back up, and pull the plug, it just goes back into hibernation mode.

HOWEVER-
I can turn on my MacBook, and pull the adapter, then put it in target disk mode, and get a full four hours of life from it without the adapter attached. This is AFTER the notebook has hibernated due to "Low Battery"

Like I said before, i've tried calibrating it, and pretty much everything else, iStat Pro says my battery has 93% health after 169 Charge Cycles. I've even brought it to the Apple Store and they've said it's perfectly OK after running a battery test via apple hardware test.

I mainly use it connected to a cinema display, it has not really been used on battery besides a few charge cycles a month for the past 6 months. When i first got it, I put about 3 full cycles on a day.

What could be the problem?

Attached is my battery information from system profiler:

Battery Information:

Model Information:
Manufacturer: DP
Device name: bq20z451
Pack Lot Code: 0000
PCB Lot Code: 0000
Firmware Version: 0003
Hardware Revision: 0002
Cell Revision: 0100
Charge Information:
Charge remaining (mAh): 4527
Fully charged: No
Charging: No
Full charge capacity (mAh): 5077
Health Information:
Cycle count: 170
Condition: Normal
Battery Installed: Yes
Amperage (mA): -1046
Voltage (mV): 12014

System Power Settings:

AC Power:
System Sleep Timer (Minutes): 0
Disk Sleep Timer (Minutes): 0
Display Sleep Timer (Minutes): 12
Wake On AC Change: No
Wake On Clamshell Open: Yes
Wake On LAN: Yes
Display Sleep Uses Dim: No
Battery Power:
System Sleep Timer (Minutes): 10
Disk Sleep Timer (Minutes): 10
Display Sleep Timer (Minutes): 2
Wake On AC Change: No
Wake On Clamshell Open: Yes
Current Power Source: Yes
Display Sleep Uses Dim: Yes
Reduce Brightness: Yes

Hardware Configuration:

UPS Installed: No

AC Charger Information:

Connected: No
Charging: No

Power Events:

Next Scheduled Events:

Type: Wake or Power On
Scheduled By: Repeating Event
Time: 7/30/10 7:00 AM

Type: Shut Down
Scheduled By: Repeating Event
Time: 7/30/10 1:45 AM

Repeating Events:

Type: Wake or Power On
Time: 6:00 AM every day

Type: Shut Down
Time: 1:45 AM every day


Thank you for your help!

 

[AppleNewton]

Full charge capacity (mAh): 5077

Thats the thing right that is a little off to me.
I tend to use my 13" plugged in alot at the desk...i guess it gets alittle too convenient.

One thing i noticed when my full charge capacity is the battery life tends to go down with it. so what i do is charge it all the way, let it drain to about 90% charge it back up and then later on after a few hours drain it down to about 80% and charge it back up.

it seemed to kick up the full charge capacity and kind of flex the battery a bit more...but thats in my own experience. so it may not be the "official" way but its what i noticed improved my battery life before i allowed it be without a powersource for too long. right now my full charge is at 5600 it was at 5300 a few months ago.

 

[GGJstudios]

This should answer most, if not all, of your battery questions: Apple Notebook Battery FAQ

 

[mgartner0622]

This should answer most, if not all, of your battery questions: Apple Notebook Battery FAQ

Thank you, but I've already taken a look at that and followed everything closley. My battery just seems to be acting strange.

 

[Jasonbot]

My 13" MacBook Pro is also acting weird. I use it connected to a screen often and although the max capacity is still rather high it just doesn't last as long as it did a few months ago.