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LevMac

macrumors 6502
Original poster
Feb 23, 2008
413
2
QLD, Australia
Just wondering why battery health would drop down to 96% from 98% using iStat Pro as my widget ?

I did a full drain of my MBA yesterday and ran it on reserve power and let it fully drain until it went to sleep, then waited about 6 hours after it went to sleep until there was no light flashing on my MBA....

I put it back on charge overnight and opened it up in the morning and it was fully charged, but the battery health now shows 96% as it was 98% a few days ago ?

How do I get the health back to over 98% ?

:confused:
 

teek

macrumors member
Feb 12, 2008
88
0
Norway
same problem here

When I got my MBA iStat Pro said 3 cycles already, and battery health was at 97%. Now it says 7 cycles and battery health is down to 95%.. What to do !
I do not have the issue with charging taking 8 or 10 hours or so.. It´s usually around 3-3.5. hours to fully charge.
 

twynne

macrumors 6502a
Apr 21, 2006
805
45
London, UK
I'd just keep an eye on it. Mine's had 19 cycles and it's still at 96% (not calibrated).

You can have a look on the Apple website, but I know they have a battery policy something like if your battery life is less than half of it's published life within the first year they'll replace it. I assume this will hold true for the Air as with all Macbooks.
 

LevMac

macrumors 6502
Original poster
Feb 23, 2008
413
2
QLD, Australia
Yeah its not worrying me too much, just wanting to know why it would drop by 2% ? I've also read of other users doing a full drain of the battery and a full charge, then once its fully charged, still leave it plugged into the magsafe adapter but your meant to use it for 2 hours while its fully charged.....apparently this has increased battery health ?

http://www.nvme.co.uk/main/equipment/index.html
 

twynne

macrumors 6502a
Apr 21, 2006
805
45
London, UK
Ok -this page contradicts my theory:

http://www.apple.com/batteries/replacements.html


Your one-year warranty includes replacement coverage for a defective battery. You can extend your replacement coverage for a defective battery to three years from the date of your notebook purchase with the AppleCare Protection Plan. However, the AppleCare Protection Plan for notebook computers does not cover batteries that have failed or are exhibiting diminished capacity except when the failure or diminished capacity is the result of a manufacturing defect. For MacBook Air owners, Apple offers a battery replacement service. You can purchase replacement batteries for late models of Apple notebooks directly from the Apple Store.
 

LevMac

macrumors 6502
Original poster
Feb 23, 2008
413
2
QLD, Australia
Mine has actually gotten better as I've used it. Started at 94-5%. Now at 41 cycles, charges in right about 4 hours from 0 and health is 97-8%.

Thats some good news....Good to hear its worked out well for you dude :) What steps did you take for yours ? Im just wondering, after I let the battery discharge and go into deep sleep mode for at least 5 hours before charging it, once I connect the magsafe back in, do I need to wake it out of sleep and do a full shutdown then leave it and let it charge ?
 

teek

macrumors member
Feb 12, 2008
88
0
Norway
good

Mine has actually gotten better as I've used it. Started at 94-5%. Now at 41 cycles, charges in right about 4 hours from 0 and health is 97-8%.

Makes me feel just a little bit better about my MBA.. sure hope I don´t have to return it because it would, almost, ruin my life if I had to do without it for even a day.
 

dahcheet

macrumors regular
Feb 7, 2008
221
0
Harrisburg, PA
Mine has fluctuated a bit too. When I first got iStat (about 10 cycles in or so) it was around 93% but after doing a battery config it jumped to 97-98%. It's holding steady at about 95-96% now.
 

LevMac

macrumors 6502
Original poster
Feb 23, 2008
413
2
QLD, Australia
Im glad im not the only one experiencing this, I guess its a normal thing and gets better eventually over time, another thing ive noticed is the "time remaining" changes up and down, does this happen to you guys as well ?
 

dahcheet

macrumors regular
Feb 7, 2008
221
0
Harrisburg, PA
Im glad im not the only one experiencing this, I guess its a normal thing and gets better eventually over time, another thing ive noticed is the "time remaining" changes up and down, does this happen to you guys as well ?

Constantly. It's the computer trying to calculate time remaining based on usage. Nothing wrong, no worries. :eek:
 

twynne

macrumors 6502a
Apr 21, 2006
805
45
London, UK
Im glad im not the only one experiencing this, I guess its a normal thing and gets better eventually over time, another thing ive noticed is the "time remaining" changes up and down, does this happen to you guys as well ?

There's another thread here on that subject. It fluctuates because it constantly recalculates and it depends on your usage at that moment. If you're doing something intensive obviously the estimated battery life isn't as good. One option is to change it to show percentage rather than estimated time.
 

OllyW

Moderator
Staff member
Oct 11, 2005
17,196
6,800
The Black Country, England
Makes me feel just a little bit better about my MBA.. sure hope I don´t have to return it because it would, almost, ruin my life if I had to do without it for even a day.

Battery replacements are done on the spot if you book an appointment at the Genius Bar in the Apple Store, so there's no need for your life to be ruined :D
 

teek

macrumors member
Feb 12, 2008
88
0
Norway
Battery replacements are done on the spot if you book an appointment at the Genius Bar in the Apple Store, so there's no need for your life to be ruined :D

That´s all good but the problem is that we don´t have any apple stores in Norway :mad:.
Good thing it isn´t a problem yet.. Hope it will fix itself like many people here are experiencing.
 

LevMac

macrumors 6502
Original poster
Feb 23, 2008
413
2
QLD, Australia
Ok, I drained the battery completely last night just before I went to bed and made sure it went past the reserve battery status all the way into sleep mode, after 6 hours of sleep I plugged the magsafe into the unit and timed exactly the charge time and it took 5 hours and 5 mins for the magsafe to turn green....

Just opened up the lid and turned it on, came up with the greyed out screen and the progress bar down the bottom going left to right and up in the menu bar it had 0% then switched to 100% as it detected it had been fully charged. iStat pro widget still states battery health is at 96% with 10 cycles and full charge capacity is at 4926mAh, does all this sound okay ?
 

SunshinegotaMac

macrumors newbie
Feb 23, 2008
17
0
SF
Mine is on the way back up as well. Cycling down about once a day. Taking a little over two hours to completely charge. Now at 97% health.
 

dahcheet

macrumors regular
Feb 7, 2008
221
0
Harrisburg, PA
I'm up to 23 cycle and at 97%. Mine has fluctuated from as low as 93% to as high as 99%. It's been sitting at 97% now for a few cycles. I wouldn't be too worried about 96%.
 

bostonte

macrumors regular
Jun 30, 2007
115
0
Get concerned when you start going from 100% to 0% Charge after 1.5 hours of SLEEP and the battery health reports at 60% (and doesn't get better after a few full cycles, smc reset, etc.).

My Air did that :( -- Apple swapped it out for a new one with the only question being "did you need data transferred".

Battery health in the high 90's when new is normal in my experience. I wouldn't worry at all if you aren't experiencing any other problems. I would check it again several months down the road (while still under warranty) and make sure it hasn't started dropping like crazy.

I've only got a dozen or so cycles on my current Air, but the battery health has fluctuated between 96% and 98%.
 

LevMac

macrumors 6502
Original poster
Feb 23, 2008
413
2
QLD, Australia
Hey guys, sorry to bump this thread back up, my full charge capacity is now showing 4914mAh and charge remaining 4853mAh...

Yesterday the full charge capacity was 4926mAh and now its 4914mAh, is this because of leaving it plugged into the magsafe all the time ?
 

dahcheet

macrumors regular
Feb 7, 2008
221
0
Harrisburg, PA
Hey guys, sorry to bump this thread back up, my full charge capacity is now showing 4914mAh and charge remaining 4853mAh...

Yesterday the full charge capacity was 4926mAh and now its 4914mAh, is this because of leaving it plugged into the magsafe all the time ?

I think (not 100% sure) it's because it has been plugged in to the magsafe for an extended period of time. Even though it's plugged in the battery still discharges a small amount of power. Theoretically it will hit the magic 90%* mark and start charging again, but I've never tested it.

You should be okay keeping it plugged in but I wouldn't do it for days on end. The MBA is meant to go places, so take it out! :D Even if it's only across the room to the couch :p

* I'm not sure of this exact value either but the MBA won't charge until a certain percentage is reach as discussed in a different battery thread that I don't have a link to (sorry, I'm being a little lazy this morning)
 

LevMac

macrumors 6502
Original poster
Feb 23, 2008
413
2
QLD, Australia
Thanks for the replies guys :) Im just enjoying using it and not worrying about these little things, after all you buy the product to enjoy, not to buy it and worry about these little things...

Hey does the actual charge drop in percentage ? A few days ago the charge was 99%, its been plugged into the magsafe for a while now, and its showing 97% charge through iStat widget.....
 
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