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Battery Capacity Going Down Fast?

K

kaicrawf

macrumors newbie
Original poster
Jan 31, 2015
15
0
United Kingdom
Before I start, here is my battery and Mac information:

Mac Information:

MacBook Pro (Retina, 13-inch, Mid 2014)
Processor: 2.6 GHz Intel Core i5
Memory: 8GB 1600 MHz DDR3
Graphics: Intel Iris 1536 MB
Age: 3.7 Months


Battery Information:

Cell Revision: 389
Charge Remaining (mAh): 1534
Fully Charged: No
Charging: Yes
Full Charge Capacity (mAh): 5925
(Factory Capacity = 6330 mAh)

Health Information:

Cycle Count: 78
Condition: Normal
(Health at 94%)
Battery Installed: Yes
Amperage (mA): 3756
Voltage (mV): 12056


My Mac is only 3.7 months old and the capacity has gone down 6% already?

For the first time this morning, I saw the "Plug in to a power supply" logo on my Mac's screen. I know you're not supposed to let it run out of charge but I was watching a movie on it last night and I must have knocked the charger out while I was asleep or something. Last night my capacity was at 99% and when I realised I let it run out of charge I immediately checked the Power Information in 'System Information'. I realised that it had gone down another 5% in one night.

Has it like un-calibrated or something? Has my capacity actually gone down that much or is it just temporarily saying that? If it is permanent is it worth taking to an Apple Store? I was under the impression that at the end of the 1000 cycles you're supposed to have 80% health or am I mistaken?

Thanks to anyone who helps :)
 
Artimus12

Artimus12

macrumors 6502a
Nov 13, 2011
539
114
YooKay
Batteries should be drained on a regular (monthly) basis! So if this is the first time you've drained it, I'm not surprised it's losing capacity. Yours being only 4 months old, it's probably recoverable back to full capacity at least. The crucial thing is to run it to shut down and then charge to extreme (extra few hours before unplugging) monthly.
 
GGJstudios

GGJstudios

macrumors Westmere
May 16, 2008
44,545
943
kaicrawf said:
My Mac is only 3.7 months old and the capacity has gone down 6% already?

Has it like un-calibrated or something? Has my capacity actually gone down that much or is it just temporarily saying that? If it is permanent is it worth taking to an Apple Store? I was under the impression that at the end of the 1000 cycles you're supposed to have 80% health or am I mistaken?
Click to expand...
Your battery is fine. It is perfectly normal if your battery health (maximum capacity) is more or less than 100%, even when brand new, or if it fluctuates up or down over time. The gradual decline is not in a straight line downward, and it may decline more rapidly at some times and slower at others. For further details, read the CHECKING STATUS AND HEALTH section of the following link.
​
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.
Artimus12 said:
Batteries should be drained on a regular (monthly) basis! So if this is the first time you've drained it, I'm not surprised it's losing capacity. Yours being only 4 months old, it's probably recoverable back to full capacity at least. The crucial thing is to run it to shut down and then charge to extreme (extra few hours before unplugging) monthly.
Click to expand...
This is false and very bad advice. The built-in batteries in the newer Mac unibody notebooks come pre-calibrated and do not require regular calibration like the removable batteries in older Apple notebooks.

Run on battery whenever you need to and plug it in whenever you can. You can plug or unplug any time you need to, regardless of the charged percentage, and you never need to completely drain your battery. Fully draining your battery is bad for it and will shorten its life.
 
S

snaky69

macrumors 603
Mar 14, 2008
5,908
488
kaicrawf said:
Before I start, here is my battery and Mac information:

Mac Information:

MacBook Pro (Retina, 13-inch, Mid 2014)
Processor: 2.6 GHz Intel Core i5
Memory: 8GB 1600 MHz DDR3
Graphics: Intel Iris 1536 MB
Age: 3.7 Months


Battery Information:

Cell Revision: 389
Charge Remaining (mAh): 1534
Fully Charged: No
Charging: Yes
Full Charge Capacity (mAh): 5925
(Factory Capacity = 6330 mAh)

Health Information:

Cycle Count: 78
Condition: Normal
(Health at 94%)
Battery Installed: Yes
Amperage (mA): 3756
Voltage (mV): 12056


My Mac is only 3.7 months old and the capacity has gone down 6% already?

For the first time this morning, I saw the "Plug in to a power supply" logo on my Mac's screen. I know you're not supposed to let it run out of charge but I was watching a movie on it last night and I must have knocked the charger out while I was asleep or something. Last night my capacity was at 99% and when I realised I let it run out of charge I immediately checked the Power Information in 'System Information'. I realised that it had gone down another 5% in one night.

Has it like un-calibrated or something? Has my capacity actually gone down that much or is it just temporarily saying that? If it is permanent is it worth taking to an Apple Store? I was under the impression that at the end of the 1000 cycles you're supposed to have 80% health or am I mistaken?

Thanks to anyone who helps :)
Click to expand...

Battery health fluctuates a lot, don't sweat it. It could very well go back up.
 
Artimus12

Artimus12

macrumors 6502a
Nov 13, 2011
539
114
YooKay
from the Apple Support website:
You can calibrate your iBook, PowerBook, MacBook, or MacBook Pro computer's lithium-ion battery for best performance.

The battery has an internal microprocessor that provides an estimate of the amount of energy in the battery as it charges and discharges. The battery needs to be recalibrated from time to time to keep the onscreen battery time and percent display accurate and to keep the battery operating at maximum efficiency. You should perform this procedure when you first use your computer and then every few months after that. If you normally leave your Apple portable computer connected to AC power and very rarely use it on battery power you may want to perform this process once a month.
Click to expand...

http://support.apple.com/en-gb/HT201575

It's a fallacy to believe that Li-Ion batteries don't need recalibrating every now & then, and since Apple didn't reinvent the battery for their latest models, it's misinformation to say so too, Mr. GGJ.

Battery University - Battery Calibration

OP: Calibrate your battery and see the results for yourself - the proof is in the eating. :cool:

BTW: after 103 cycles mine still charges to 102% and I calibrate every month or so.
 
GGJstudios

GGJstudios

macrumors Westmere
May 16, 2008
44,545
943
Artimus12 said:
from the Apple Support website:


http://support.apple.com/en-gb/HT201575

It's a fallacy to believe that Li-Ion batteries don't need recalibrating every now & then, and since Apple didn't reinvent the battery for their latest models, it's misinformation to say so too, Mr. GGJ.
Click to expand...
From the very same web page you linked. Apparently, you didn't read it all:
Portables with built-in batteries

Current Apple portable computer batteries are pre-calibrated and do not require the calibration procedure outlined in this article. These computers use batteries that should be replaced only by an Apple Authorized Service Provider.
Click to expand...
 
GGJstudios

GGJstudios

macrumors Westmere
May 16, 2008
44,545
943
Artimus12 said:
I read it, but I know that Li-Ion batteries need calibration - apparently you don't. As I said, the proof is in the eating.
Click to expand...
You haven't calibrated, so you don't know. Yet another one claiming they know better than the manufacturer. :rolleyes:
 
J

joe-h2o

macrumors 6502a
Jun 24, 2012
997
445
Artimus12 said:
I read it, but I know that Li-Ion batteries need calibration - apparently you don't. As I said, the proof is in the eating.
Click to expand...

Apple's current internal batteries do not require this procedure because they have the ability to recalibrate during normal use.

The support article is unambiguous. You do not need to drain and charge monthly; normal use is more than sufficient.

You are advocating a procedure based on partially quoting a support document that is intended for a different product and your own "common sense" that is in direct contradiction to Apple's stated procedure.

For anyone with a retina Macbook Pro, all you have to do is use your computer normally. Plug it in when needed, use it on battery when you need it. Keep it away from extreme heat and extreme cold.
 
Artimus12

Artimus12

macrumors 6502a
Nov 13, 2011
539
114
YooKay
what's the harm in the OP TRYING a calibrate? or would you prefer everyone with an Apple product to be spoon fed for the entire lifetime of the product? It won't hurt if it fails to work, but it might be all the Battery needs to straighten it out.
 
GGJstudios

GGJstudios

macrumors Westmere
May 16, 2008
44,545
943
Artimus12 said:
what's the harm in the OP TRYING a calibrate?
Click to expand...
Because nothing is wrong with the OP's battery. Because calibration is not recommended by Apple for the OP's computer. Because calibration requires fully draining the battery, which is bad for it, and can shorten its life. Because trying useless procedures that can do more harm than good isn't a prudent approach to troubleshooting. The OP was simply unaware of the normal battery health behavior. Education, not calibration, is the only thing appropriate to answer the OP's question.
 
Natzoo

Natzoo

macrumors 68000
Sep 16, 2014
1,986
631
So my battery max was 7698 and i left it charging all night and its max is 7960. So it does go up
 
GGJstudios

GGJstudios

macrumors Westmere
May 16, 2008
44,545
943
Natzoo said:
So my battery max was 7698 and i left it charging all night and its max is 7960. So it does go up
Click to expand...
Yes, as stated in post #3: "It is perfectly normal if your battery health (maximum capacity) is more or less than 100%, even when brand new, or if it fluctuates up or down over time."
 
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