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Raymund

macrumors newbie
Original poster
Feb 9, 2015
23
8
Budapest, Hungary
Hi all!!!

I'm new to here!!!

I have a 2014 13 " MBA and I read many discussions and threads (here and other sites) in this question! But I can't decide in this question!

So, is it good for my macbook air if i plugged in when it's fully charged or bad for the batteries? For example: when i at home i use my macbook air always plugged in.

I read many theories, when always plugged in is bad for batteries.
But i think, it's bad when my batteries has many cycle, many charging up to 100% and discharging to low level, 10-20%!

What is the exact truth?
Somebodies says, the ions needs to moving, so need some discharging! Im so confused!
So, keep plugged in always, or sometimes do a moderate discharging (40-50%)??

Thanks for the answers!!! :cool:
 

GGJstudios

macrumors Westmere
May 16, 2008
44,509
911
So, is it good for my macbook air if i plugged in when it's fully charged or bad for the batteries? For example: when i at home i use my macbook air always plugged in.
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.
The link below should answer most, if not all, of your battery/charging questions, including tips for maximizing battery performance. If you haven’t already done so, I highly recommend you take the time to read it.
 

Newtons Apple

Suspended
Mar 12, 2014
22,757
15,250
Jacksonville, Florida
Leaving it plugged in all the time will not harm your battery. The charging circuit will stop charging when the battery is full and kick back in when the charge has dropped to a specified level. It will not hurt the laptop of battery.
 
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SFStateStudent

macrumors 604
Aug 28, 2007
7,496
3
San Francisco California, USA
Agreed, I pay close attention to the number of cycles on the battery! I also bought the new 2014 MBA 1.7GHz 512GB and already had (3) cycles on it when I got it home. Gave my 2008 MB Pro (Classic) 2.5GHz to my son and it had 33 cycles on the battery and tried to plug in 24/7. Always nervous about 2-4 hours of battery and even bought a new backup battery. Now we can enjoy 10-12 hours of battery life...:cool:
 

Raymund

macrumors newbie
Original poster
Feb 9, 2015
23
8
Budapest, Hungary
Agreed, I pay close attention to the number of cycles on the battery! I also bought the new 2014 MBA 1.7GHz 512GB and already had (3) cycles on it when I got it home. Gave my 2008 MB Pro (Classic) 2.5GHz to my son and it had 33 cycles on the battery and tried to plug in 24/7. Always nervous about 2-4 hours of battery and even bought a new backup battery. Now we can enjoy 10-12 hours of battery life...:cool:

So, it's better always on power adatper or not??? It's not clear, what is the better for the batteries.
I red somewhere, to keep always on the adapter is bad for the batteries --> it's casuse low cycle but the batteries condition is low ie: 70%..
So how it charge???
 

Meister

Suspended
Oct 10, 2013
5,456
4,309
So, it's better always on power adatper or not??? It's not clear, what is the better for the batteries.
I red somewhere, to keep always on the adapter is bad for the batteries...
Keep it plugged in all the time
 

snaky69

macrumors 603
Mar 14, 2008
5,908
488
So, it's better always on power adatper or not??? It's not clear, what is the better for the batteries.
I red somewhere, to keep always on the adapter is bad for the batteries --> it's casuse low cycle but the batteries condition is low ie: 70%..
So how it charge???

Did you even bother reading GGJstudios's answer? The short of it is: it does not matter. I repeat: It. Does not. Matter. The power supply gives power to the battery when the battery asks it to. The battery is equipped with charging circuitry that manages when and how much power to draw from the power supply. If the battery's full, it stops charging. Plain and simple.

To prevent damage from keeping it full all the time, the same circuits allow it to trickle discharge to 95% and charge it back up to 100% when you're plugged it for very long periods of time.

TL;DR: do whatever you like with your battery, it doesn't care.
 

GGJstudios

macrumors Westmere
May 16, 2008
44,509
911
To prevent damage from keeping it full all the time, the same circuits allow it to trickle discharge to 95% and charge it back up to 100% when you're plugged it for very long periods of time.
Actually, Apple has stated that their battery technology is designed to avoid such shallow discharge/recharge activity, which is why batteries won't charge if they're plugged in when already charged to 93% or more.

Their statement is as follows:
Symptoms
Some Apple portable computers (PowerBook G4, iBook, MacBook Pro, MacBook, and MacBook Air) may not show the battery as 100 percent charged in Mac OS X, even when the power adapter is connected.

Note: Intel-based computers may stop charging between 93 and 99 percent.

Resolution
This is normal. The batteries used in these computers are designed to avoid short discharge/charge cycles in order to prolong the overall life of the battery.

When setting the Mac OS X battery status menu bar icon to display charge state by percentage, you may notice that the reported charge stays between 93 or 95 percent and 99 percent.

To allow the adapter to recharge the battery to 100%, simply allow the charge to drop below 93%. The adapter will automatically recharge the battery to 100%.
 

motrek

macrumors 68030
Sep 14, 2012
2,606
296
Actually, Apple has stated that their battery technology is designed to avoid such shallow discharge/recharge activity, which is why batteries won't charge if they're plugged in when already charged to 93% or more.
...

I think you misread the post, snaky69 said trickle discharge and not trickle charge.

Good call on Apple's part. I wonder how many hours/days it takes the laptop to drop from 100% to 95%. So you're really only charging the laptop a tiny percentage of the time.
 

GGJstudios

macrumors Westmere
May 16, 2008
44,509
911
I think you misread the post, snaky69 said trickle discharge and not trickle charge.
I didn't misread it. It's not designed to trickle discharge at all. Once a battery is fully charged, it stops charging and runs on AC power for as long as it's plugged in. Only in rare circumstances will it discharge the battery, when power demands require more than AC power alone can provide.
 

snaky69

macrumors 603
Mar 14, 2008
5,908
488
I didn't misread it. It's not designed to trickle discharge at all. Once a battery is fully charged, it stops charging and runs on AC power for as long as it's plugged in. Only in rare circumstances will it discharge the battery, when power demands require more than AC power alone can provide.

Except that it does discharge. My MBP has been plugged in for the past month or so, it had charged to 100%, and is currently sitting at 97%.
 

GGJstudios

macrumors Westmere
May 16, 2008
44,509
911
Except that it does discharge. My MBP has been plugged in for the past month or so, it had charged to 100%, and is currently sitting at 97%.
Batteries will lose their charge over time, even if nothing is drawing power from them. There is also a possibility that at some time during the month, your MBP required more power than AC alone would provide. There is no design for the batteries to "trickle discharge" or "trickle charge", as these are not good for battery health. That is why Apple technology specifically avoids them.
 

motrek

macrumors 68030
Sep 14, 2012
2,606
296
I didn't misread it. It's not designed to trickle discharge at all. Once a battery is fully charged, it stops charging and runs on AC power for as long as it's plugged in. Only in rare circumstances will it discharge the battery, when power demands require more than AC power alone can provide.

It's confusing because I don't think there's any such thing as "trickle discharge," only trickle charge. I assume the OP was referring to the battery gradually losing charge over time, which happens to all batteries naturally.
 

Raymund

macrumors newbie
Original poster
Feb 9, 2015
23
8
Budapest, Hungary
But please, explain this: I have red many user report and they have 200 or more cycle in they battery and the conditions 75 % or more less...!! I'm afraid from this, after one year my batteries will be dying...
So the 200 or more cycle is not near to the apple guaranteed 1000 cycles and 80% battery condition.

So, my main question, how to prolong and protect my batteries dying (75% or less battery condition) if I loaded 200 or more cycle!!!
 

motrek

macrumors 68030
Sep 14, 2012
2,606
296
But please, explain this: I have red many user report and they have 200 or more cycle in they battery and the conditions 75 % or more less...!! I'm afraid from this, after one year my batteries will be dying...
So the 200 or more cycle is not near to the apple guaranteed 1000 cycles and 80% battery condition.

So, my main question, how to prolong and protect my batteries dying (75% or less battery condition) if I loaded 200 or more cycle!!!

And there are also a bunch of people who keep their laptops plugged in (almost) all the time and have excellent battery health. I sold my 2010 MBA last year and it had ~150 cycles on the battery and it was ~4 years old and had 90% of its original battery capacity.

It's unclear what's going wrong with these people who have poor battery health.

I have a suspicion that their laptops may have been exposed to high-temperature conditions. High temperatures can start a chemical reaction inside batteries that can ruin them.

They may have left their laptops in a car on a hot day or maybe sitting on a desk near a window on a very sunny day.

In any case, there are enough people who leave their laptops plugged in all the time and have no problem with battery health that that can't possibly be causing a problem.
 

GGJstudios

macrumors Westmere
May 16, 2008
44,509
911
But please, explain this: I have red many user report and they have 200 or more cycle in they battery and the conditions 75 % or more less...!! I'm afraid from this, after one year my batteries will be dying...
So the 200 or more cycle is not near to the apple guaranteed 1000 cycles and 80% battery condition.
It is perfectly normal if your battery health (maximum capacity) 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 Apple Notebook Battery FAQ I posted earlier. You really should just relax and enjoy your Mac and don't obsess about your battery. If it drops below 80% before 1000 cycles and you still have warranty or AppleCare, Apple will replace it for you.
 

Raymund

macrumors newbie
Original poster
Feb 9, 2015
23
8
Budapest, Hungary
And there are also a bunch of people who keep their laptops plugged in (almost) all the time and have excellent battery health. I sold my 2010 MBA last year and it had ~150 cycles on the battery and it was ~4 years old and had 90% of its original battery capacity.

It's unclear what's going wrong with these people who have poor battery health.

I have a suspicion that their laptops may have been exposed to high-temperature conditions. High temperatures can start a chemical reaction inside batteries that can ruin them.

They may have left their laptops in a car on a hot day or maybe sitting on a desk near a window on a very sunny day.

In any case, there are enough people who leave their laptops plugged in all the time and have no problem with battery health that that can't possibly be causing a problem.


How do you use your notebook??? (if you have now)
 

motrek

macrumors 68030
Sep 14, 2012
2,606
296
How do you use your notebook??? (if you have now)

Personally I mostly use a desktop computer (Mac Mini) and just leave my MBA plugged in in a corner.

If I go to a coffee shop or a friend's house to do some work, I will take my MBA and run it on battery power for a few hours. Then I'll bring it home and plug it back in.

If I go on a trip, I will use the laptop in airports, on planes, and at hotels. It often isn't convenient to keep the laptop plugged in and I will often run the laptop's battery down to less than 20-30% before recharging. This happens every few months.

My current MBA's battery is 8 months old, has 28 cycles on it, and it has 101% of its factory capacity. :)
 

Meister

Suspended
Oct 10, 2013
5,456
4,309
How do you use your notebook??? (if you have now)
rmbp 2013 13", 1.5 years old, 102 cycles, 97% factory capacity.

I normally do not leave it plugged in for a bunch of other reasons.
I recharge after use or if the battery goes below 90%.
 

Raymund

macrumors newbie
Original poster
Feb 9, 2015
23
8
Budapest, Hungary
So the conclusion is this:
don't discharge the batteries it a very low level, 10-20%... Keep it a higher percentage, and plug in if I can!
 

GGJstudios

macrumors Westmere
May 16, 2008
44,509
911
So the conclusion is this:
don't discharge the batteries it a very low level, 10-20%... Keep it a higher percentage, and plug in if I can!
If you have a need to run on battery power below 10% on occasion, there's nothing to worry about. You don't need to intentionally drain it to any particular level, and you don't need to avoid any certain discharge percentage, except fully draining it is not recommended. My original recommendation tells you all you need to know:

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.
 

tmarks11

macrumors 6502a
May 3, 2010
509
32
So, keep plugged in always, or sometimes do a moderate discharging (40-50%)??

Here is your best choice: just use it and don't worry about it.

I probably run down to the 7% point at least every other day. Some days I never unplug it. It is almost 3 years old. 768 cycles at 82% capacity. I bet the battery will last me at least another year.

After that? Either pay $90 for a new battery (replacement is simple; a 5 minute job), or maybe it is time for a MBA r12 (but probably not, I will just keep using it, I am sure, because I am a cheapskate).

If I can get 4 years out of the battery without worrying or babying it, than I don't think it is worth wasting your time try to decide on your "usage pattern".

My wife's 1011 MBA has 1332 cycles and is at 62% capacity. System information says "replace soon". I guess that kind of tells you what you can get out of a battery.

So maybe somebody here babies their battery, and gets 5 years of life out of it? So how many people are using a 5 year old laptop right now?

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.
Exactly what he said. You don't need to worry about it. This isn't the year 2000 with NiCd batteries (man those sucked).
 
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