New Macbook Air 2018 battery health

BLBL

macrumors 6502a
Original poster
Apr 11, 2018
707
100
Out of curiosity, what battery health percentage / mAh reading others see in their Air 2018 and how many charge cycles? Also it would be especially interesting to hear what reading others saw when unit was right out of the box and how it developed after first few charge cycles.

Mine ended up only 98.5% health after very first charge (I received new machine with completely empty battery). Health did creep up after using machine after first charge to over 4450mAh but reading was moving all the time. Now after second charge it ended up 4359mAh (design capacity 4381mAh), so still already below design capacity and this time did not seem to raise when I unplugged charger and continued using it a little while.

So would be interesting to hear if others managed to keep their Air battery at or over design capacity and for how long, or are these really supposed to start dropping right after unboxing the brand new unit?
 

BLBL

macrumors 6502a
Original poster
Apr 11, 2018
707
100
I had a chance today to quickly check a demo Air 2018 unit that had over 180 charge cycles already and its battery had still a bit over 4300mAh, so it being that high after that many charge cycles suggests that battery in Macbook's should be like ones used in iPhones and iPads which are over their nominal capacity when device is new and it stays there for some time.

So obviously my new Air after 2 charge cycles dropping to around 99% is troubling. I received my brand new Air with completely empty battery (I had to plug it in to be able to power it on for the very first time), probably due to reason it was manufactured about 5.5 months earlier which probably damaged battery some.
 

axeldtf

macrumors 6502
Mar 3, 2007
340
1
I bought the MBA when it came out. how would I check the battery health and what should i be looking for? I think i've only charged it about 30 times as it's not my daily driver. But after reading you post i am curious.
 

BLBL

macrumors 6502a
Original poster
Apr 11, 2018
707
100
It would be great to hear what health percentage other see on their Air 2018.

There are many ways to check it, even native Mac OS shows it if you hold down options key and then click apple logo and select first menu item that shows there and then Power from the list of available items. It shows there battery max. capacity in mAh and how much current battery level in mAh is.

Another and the easiest way is to download free CoconutBattery from appstore. It shows all the necessary information right away. It even tells you device and battery manufacturing dates, so compare those to day you bought yours and you see how long it was sitting in storage.
 

auxbuss

macrumors regular
Feb 18, 2014
167
135
UK
Out of curiosity, what battery health percentage / mAh reading others see in their Air 2018 and how many charge cycles? Also it would be especially interesting to hear what reading others saw when unit was right out of the box and how it developed after first few charge cycles.

Mine ended up only 98.5% health after very first charge (I received new machine with completely empty battery). Health did creep up after using machine after first charge to over 4450mAh but reading was moving all the time. Now after second charge it ended up 4359mAh (design capacity 4381mAh), so still already below design capacity and this time did not seem to raise when I unplugged charger and continued using it a little while.

So would be interesting to hear if others managed to keep their Air battery at or over design capacity and for how long, or are these really supposed to start dropping right after unboxing the brand new unit?
4465 after 60 cycles. I've had the machine since November.
 

BLBL

macrumors 6502a
Original poster
Apr 11, 2018
707
100
does this help?
Yes, it clearly shows similar thing what I'm experiencing with mine. My Air has currently 4 charge cycles and battery health fluctuates around 4325-4340mAh (it should be 4381mAh or over), so battery health is 99% and under at the best.
While that might looks good for many, I beg to differ. From what Apple tells us these batteries are supposed to last 1000 charge cycles. If that's true I would not expect to see any degradation in brand new unit after first couple charge cycles.

Based on the photos you posted, it looks like you are suffering from similar issue as I. Yours has only 39 charge cycles and battery is already 4269mAh (it should be 4381mAh (design capacity) or more at that point.

4465 after 60 cycles. I've had the machine since November.
Yours looks like A-grade battery, congratulations. 4465mAh is well over nominal design capacity of 4381 and since that is after 60 cycles, it is probably pretty stable by now.

It looks like it is lottery if one gets good or bad quality battery in their devices. Personally I'm ****** battery magnet. Every Apple gear I've purchased within one year came with horrible battery that sunk pretty quickly under design capacity or was sunk practically out of the box (like my Air 2018). Our other family member has at the same time purchased couple Apple products and they all came with A-grade battery that hold easily over design capacity for long time, even person who uses them does not practice any reasonable charging habits but lets them even run empty.
My point here, do not blame your charging habits if battery starts degrade within first few - few dozen charge cycles, It is weak battery and not user error at that point. Real issues with charging habits will occur much much later.

Are you guys happy with the display? Do you see banding issues? Like when you view this page https://www.apple.com/macbook-pro/
Looks at that first photo of the Macbook there and pay attention to light effect surrounding the notebook. Especially in lower left corner and then area around touchpad and to the right all the way,
Try turning brightness setting to 100% and is possible try viewing that image in dimmer room so that you can see dark image areas well. That scene is nearly impossible to look detailed in bright light on.

In my Air 2018 there is noticeable banding / oil painting look in this light effect, as if display color depth is from 24bits to 16bit or similar. Also can you comment on whether your machines came with LG or Samsung panel. Mine came with LG.
 
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0014

macrumors 6502a
May 23, 2016
956
590
Middle East
This is mine after 54 Cycles. Had it since mid-Dec 18 and used it 5 days a week for around 5-6hrs a day and 2-3 hrs a day at weekends. So shows how good the battery life is. It may even go back to 100% once it I fully charged. But generally only charging once every 2-3 days.

Screenshot 2019-07-01 at 14.27.41.png
 

BLBL

macrumors 6502a
Original poster
Apr 11, 2018
707
100
Do you have any battery health info from the time it had less charge cycles? Mine is about the same or little less than yours but only 4 charge cycles…
 

0014

macrumors 6502a
May 23, 2016
956
590
Middle East
As suspected, now fully charged

Screenshot 2019-07-01 at 18.52.58.png


With updating to Catalina I had to reinstall the app and my previous weren't saved. I have this from when at 26 cycles but that is all I have left. I did post a reply somewhere else in here a while back showing a few. But can't remember if that was with my iOS devices or my old MBP. Will see if I can find it.

Screenshot 2019-03-28 at 10.36.08.png
 

BLBL

macrumors 6502a
Original poster
Apr 11, 2018
707
100
As suspected, now fully charged
Mine seems also occasionally raise max. capacity a bit for a while when charging or fully charged but it drops very quickly after unplugging the charger. For example today I plugged in charger and max. capacity was only around 4320-4330 and stayed there during charging, but I had to remove charger for a moment when it was around 50% charged and during that couple of minutes max. capacity creeped up to 4391. I plugged it in again and left it charging and max. capacity stayed at 4391 even when charging was completed but after I removed charger it dropped within 1-2 minutes back to around 4320-4330. Obviously weak battery.

My battery seems to be SMP/Simplo brand. What battery other have in their units?
I checked couple shop demo units which also had excellent over 4400 max. capacity and those were other brand battery, DNY (edit: I think it was DSY) if I recall correctly. Maybe better quality battery from DNY/DSY??
 
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BLBL

macrumors 6502a
Original poster
Apr 11, 2018
707
100
Another interesting thing I noticed when I checked few Air 2018 demo models at local shop. Those machines had older manufacturing date than mine but still battery revision was 1842 while in mine it is 1838 even battery manufacturing date is newer in mine. Yet they still had full charge capacity higher than design capacity (even some of them had a lot of charge cycles already). Those demo models had DSY brand battery while mine is SMP but I saw other model demo models with SMP battery and 1842 revision, so obviously battery revision is not tied to battery brand.

My battery seems to stay under design capacity. It has somewhat stabilized maybe around 4310-4330. It vary quite a bit.
Even sometimes when unplugging charger in the middle of charging cycle and wait a moment full charge capacity can creep up to even 4380 but when plugging in charger and checking when it has reached 99% charge level (which is the highest it will get and then it will just pause until reach 100% where it jumps to show the same as full charge capacity) it is only like 4330 and not increasing slowly to full charge capacity value (it just jumps there instantly after maybe 20-30 minutes later. I've seen that in other Apple devices also, so I guess that behaviour itself is normal for them but point is that in this case actual charge never reach what is claims it to be). I know it was explained in complicated way but if you read carefully, you get what I'm saying. Before anyone question why it would matter is that, as soon as (there is a little delay until meter gets updated) charger is removed it will drop full charge capacity to about the same value as it was when it showed 99% charge level during near the end of the charging cycle (like it showed 4330 at 99% and 4380 at 100% but as soon as unplugged it drops back to 4330, so in never really goes as high as it claimed).
 

BLBL

macrumors 6502a
Original poster
Apr 11, 2018
707
100
battery.jpg
Here is screenshot of my battery condition. In this photo there is actual two charging times and other are numbers between charging, so that second line from the top and 4th from the bottom are actual charges. As you can see it has been dropping very fast!

It was even on the very first charge where it reached only 98,5%/4315mAh capacity but it did go somewhat higher during use, and was short time even over 4400mAh but it did not last long.

I'm wondering how common this is? Maybe I should just take an easy way and return the unit… Unfortunately the dealer has not sale price for this model at the moment, and since I got mine at pretty nice price I'm really not trying to hesitate too much in case this turns out to be normal for this model.

Another thing is battery life because it is not that good. For example I got maybe 5,5 hours total use (actual use with screen on) and battery went from 100% to 29%!!! I usually never drive battery that low, but I wanted to get some feeling about how long it can run on full charge. In this 5,5 hours I was using it pretty actively with several Safari tabs open and screen brightness vary from full minus 4-5 clicks but at times I had it even turned at 100% for short periods of time and I have external 2.5" USB hdd connected for maybe 45 minutes, so pretty active use. But still, pretty high power consumption. I have felt all the time that I does not run anywhere near 10 hours on full charge but that was the first time I actually tracked how long it run.

I'd be appreciated for any comments!
 

bcaslis

macrumors 68020
Mar 11, 2008
2,164
188
No offense but you are way overthinking this. Batteries are analog, not digital. That 1 or 2% you are fretting over is meaningless. Note that that it went back up on the last to 99%. This is normal. You can't extrapolate a degeneration based on this. That difference between the charge and capacity is absolutely normal. I see the same thing on a 2018 MacBook Pro 13" and a 2018 MacBook Air. Look under system reporter. Does it battery condition is normal? If so, then stop looking at numbers to the third decimal point, use the machine and be happy.
 

BLBL

macrumors 6502a
Original poster
Apr 11, 2018
707
100
Could you post what readings you got on your Pro and Air?

My experience with battery health in iPhones and iPads is that this number really has big effect and that decent battery should at least 100% or more. From what I've seen even slight drop in health seems to mean battery is weak. It cannot hold voltage and current when load is applied. For example in our family there are two iPhone X, other has battery all the time battery over 102% and other has just below 99% or less. Better one goes easily 1-2 day longer between charges than weaker one with same use and all conditions. Also my iPad battery dropped to only around 8000mAh and it barely runs 7-8 hours at the most when it did 10 hours when battery was 100% health.

I noticed that my new Air 2018 runs only 5,5 hours 100% > 29% battery, so it cannot run anywhere near promised 10 hours. So even slight drop in battery health = huge decrease in run time. I know batteries are analog and their health is hard to quantify in numbers but obvious correlation it where battery health is at nominal or higher capacity vs even slight drop under that. From that downwards it is uncharted territory from totally unusable to just drop in run times. I've never seen anyone having problems with battery run time or reboot when battery health is 100% or more but just below that your can have all kinds or unexpected problems or not.
 

bcaslis

macrumors 68020
Mar 11, 2008
2,164
188
My experience does not match your. I have never ever seen something with greater than 100% health. What tool are you using? In system reporter it shows 4307 mAh with total capacity of 4320. This is with it plugged in and fully charged. My MBP which is almost 1 year old shows 4954 out of 5084. These are 99.6% and 97.4%.
 

BLBL

macrumors 6502a
Original poster
Apr 11, 2018
707
100
Try this https://www.coconut-flavour.com/coconutbattery/
I shows you how you battery is doing. Based on 4320 mAh, your Air battery health has reduced already (it should be 4381). Pretty much every Apple gear usually have over 100% battery when new, if battery is healthy in the begin with.
 

bcaslis

macrumors 68020
Mar 11, 2008
2,164
188
Not it should not. I have never ever seen this (over 100%). You are fretting over nothing. You should return or sell your MacBook Air because it's clear you will never be happy with it. I've had more Apple gear than I can count and I have never experienced your claims.
 
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BLBL

macrumors 6502a
Original poster
Apr 11, 2018
707
100
If all your Apple gear never had battery health over 100% even when they were new, I guess you must be very unlucky like me recently and not getting a winning ticket in battery lottery.
Just check this thread for example. All who commented had over or about even 100% battery on Air 2018 even after many charge cycles.
https://www.reddit.com/r/macbookair/comments/ah6kk8/full_charge_capacity_for_mba_2018/

https://www.reddit.com/r/macbookair/comments/bcc6bk/mba_retina_question_about_the_full_charge_capacity/
 
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