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Old Mar 23, 2013, 09:12 PM   #1
Ewang1
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My battery dropped to 84.6%

"MaxCapacity" = 5668
| | "CurrentCapacity" = 577
| | "LegacyBatteryInfo" = {"Amperage"=3438,"Flags"=7,"Capacity"=5$
| | "DesignCapacity" = 6700

Cycles: 357
8.9month old

Why???
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Old Mar 23, 2013, 09:15 PM   #2
GGJstudios
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Quote:
Originally Posted by Ewang1 View Post
"MaxCapacity" = 5668
| | "CurrentCapacity" = 577
| | "LegacyBatteryInfo" = {"Amperage"=3438,"Flags"=7,"Capacity"=5$
| | "DesignCapacity" = 6700

Cycles: 357
8.9month old

Why???
Why what?
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Old Mar 23, 2013, 09:25 PM   #3
B...
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Do not rely on apps to tell you battery health. They can be innacurate and fluctuate a lot.
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Old Mar 23, 2013, 09:27 PM   #4
simsaladimbamba
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As you discharged the computer completely 1.3 times per day in the last 8.9 months, you may have led to this by yourself. It is not necessary to discharge the battery daily if you have the ability to connect to power.
______________________________________________________
This should answer most, if not all, of your battery questions:
Apple Notebook Battery FAQ by GGJstudios
The F.A.Q. includes the following topics:
  • BATTERY INFORMATION
  • BATTERY LIFE FROM A CHARGE
  • AC POWER
  • CALIBRATION
  • BATTERY LIFESPAN
  • CHECKING STATUS AND HEALTH
  • CHARGING
  • WHAT IS A CYCLE?
  • BATTERIES ARE NOT COVERED
  • BULGING OR SWELLING BATTERY


______________________________________________________
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Old Mar 23, 2013, 09:43 PM   #5
Ewang1
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Is my battery life appear to be normal?
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Old Mar 23, 2013, 09:52 PM   #6
RichardC300
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Sounds right. I'm at 279 cycles and 91% of max capacity.
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Old Mar 23, 2013, 10:03 PM   #7
Ewang1
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I see. I thought discharging would help the battery flow better... ( i mean healthier)
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Old Mar 23, 2013, 10:04 PM   #8
simsaladimbamba
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Quote:
Originally Posted by Ewang1 View Post
I see. I thought discharging would help the battery flow better...
It does not with modern batteries. Read the FAQ I linked to.
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Old Mar 23, 2013, 10:07 PM   #9
GGJstudios
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Quote:
Originally Posted by Ewang1 View Post
Is my battery life appear to be normal?
Yes, quite normal.

The link below should answer most, if not all, of your battery/charging questions. If you haven't already done so, I highly recommend you take the time to read it.
Apple Notebook Battery FAQ
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Old Mar 23, 2013, 10:11 PM   #10
Ewang1
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Quote:
Originally Posted by simsaladimbamba View Post
It does not with modern batteries. Read the FAQ I linked to.
Thx. Since the data appears on the screen may fluctuate sometimes, is it still possible to restore the battery life to at least 88% if I charging it all the time?
and if I'm not using my computer, still I keep it charged or leave it plugged in order to make my battery healthier?
and if I still have, for example, 70% left in my battery, should I plug in to let it recharge to its full capacity while I'm not using my computer( like while my computer is at sleep or shutdown)?

Quote:
Originally Posted by GGJstudios View Post
Yes, quite normal.

The link below should answer most, if not all, of your battery/charging questions. If you haven't already done so, I highly recommend you take the time to read it.
Apple Notebook Battery FAQ
thx

Last edited by HexMonkey; Mar 24, 2013 at 03:34 AM. Reason: Post merge
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Old Mar 24, 2013, 07:54 AM   #11
GGJstudios
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Quote:
Originally Posted by Ewang1 View Post
Thx. Since the data appears on the screen may fluctuate sometimes, is it still possible to restore the battery life to at least 88% if I charging it all the time?
and if I'm not using my computer, still I keep it charged or leave it plugged in order to make my battery healthier?
and if I still have, for example, 70% left in my battery, should I plug in to let it recharge to its full capacity while I'm not using my computer( like while my computer is at sleep or shutdown)?
If you read the Battery FAQ, your questions should be answered.

Apple does not recommend leaving your portable plugged in all the time.
No, you can't restore battery health. Batteries die over time.
If you donít plan on using your notebook for more than six months, Apple recommends that you store the battery with a 50% charge.
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Old Mar 29, 2013, 02:21 AM   #12
Ewang1
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Thx, my battery life seems to be back after following some of your advise.
"MaxCapacity" = 6116
| | "CurrentCapacity" = 6101
| | "DesignCapacity" = 6700

It's back to 91.3%
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Old Mar 29, 2013, 09:47 AM   #13
GGJstudios
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Quote:
Originally Posted by Ewang1 View Post
Thx, my battery life seems to be back after following some of your advise.
"MaxCapacity" = 6116
| | "CurrentCapacity" = 6101
| | "DesignCapacity" = 6700

It's back to 91.3%
It will fluctuate both up and down over time, as previously stated.
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Old Mar 29, 2013, 04:59 PM   #14
Saturn1217
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To be clear I think what people are saying is that you use your battery a lot so it is natural that the total capacity has decreased. It probably has little to do with HOW you charge and discharge your battery. The sheer amount that you use it is probably outside of the "average" that Apple is considering when they provide their battery health estimates.

Batteries are a consumable resource. Even if you use your battery perfectly it only has so many charge cycles in it. Not using the battery at all is bad because electrons do need to keep flowing but the more you use it the more you use up the finite resource that is your battery capacity. Plugging in more often will simply slow the rate at which you accumulate extra cycles which in your case will probably slow the degradation of your battery health.

Still I thank you for presenting this data point because if you can maintain somewhere around 90% battery health with what comes out to 481 cycles/year (if you continue as you are doing now) then my usage (which I thought was quite high) of ~124 cycles/year should be just fine

PS. I highly suspect that the battery capacity that you read in software is an estimate (based on the software's calibration of the battery). I don't think that seeing your battery health go up to 90% means that your battery actually got better (that is actually thermodynamically impossible). It just means the software calibration changed a bit. That is my understanding anyway.
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Old Mar 29, 2013, 06:42 PM   #15
jkim13
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Just last week I got a battery service alert for my 2012 MBA. Had less than 250 cycles but health was at around 70%. I took it to the Apple store and they replaced the battery for free. Took about 10 minutes for the whole thing.

My usage wasn't out of the norm. Used it daily, charged it daily, and let it drain to red once or twice a week.
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