16” Battery capacity

nickf1

macrumors member
Original poster
Jul 23, 2018
39
11
Sydney, AU
I was checking the battery capacity last night on my new MBP 16 and I was surprised to see that it was already down 8% from the design capacity. I’m trying to recalibrate it at the moment and zapping the PRAM and SMC to see if that helps. If not, I’ll have to return the laptop because I don’t think it’s acceptable to have such a drop in capacity after only 4 cycles. What do you guys think? Is this happening to you as well?
 

Attachments


mikethebigo

macrumors 68000
May 25, 2009
1,883
196
See what happens after a calibration. There have been multiple posts about it reporting lower capacity at first, and it fixes itself pretty quickly.
 
  • Like
Reactions: nickf1

Nacho98

macrumors 6502a
Jul 11, 2019
551
452
got my 16" today.

97.1% out of the box with one cycle on a battery produced 9 days ago. Shut down for a couple hours, restarted, now 98.6% with still 1 cycle.

I'm expecting it to go up after a few cycles (but yes it sucked to see).
 

nickf1

macrumors member
Original poster
Jul 23, 2018
39
11
Sydney, AU
Just received my MBP 16" and it also has low battery design capacity. What do you guys meany by recalibrating? Drain it fully then recharge?
Yep let it die (run on battery until the Mac turns off), then plug it in and don’t unplug it until it’s full again + 1 hour more, to fully complete the charge (macOS 100% is not 100%, use coconut to be sure). That’s how mine was fixed. Since I sent the screenshot my capacity is back at 100% 😎
 

nickf1

macrumors member
Original poster
Jul 23, 2018
39
11
Sydney, AU
I've been using Macs for about 25 years now and I can vaguely remember where exactly to get battery cycles and health info. I just use the laptop and unless there's clearly an issue, I don't worry about it :)

Life's too short you crazy kids!
Haha I agree with you, but I spent a lot of money on this laptop so I wanted to be sure it was alright. Now I won’t worry about it anymore and enjoy it!
 
  • Like
Reactions: ascender

SeanLe

macrumors member
Dec 2, 2017
41
10
Australia
Had the same issue when I got mine last night. I just fully charged it then used it on battery and it corrected itself shortly after.
 

phas3

macrumors 65816
Oct 5, 2008
1,112
16
I was checking the battery capacity last night on my new MBP 16 and I was surprised to see that it was already down 8% from the design capacity. I’m trying to recalibrate it at the moment and zapping the PRAM and SMC to see if that helps. If not, I’ll have to return the laptop because I don’t think it’s acceptable to have such a drop in capacity after only 4 cycles. What do you guys think? Is this happening to you as well?
didn't have to re-calibrate mine, just plugged it in once I got it and ran it on battery for a couple of hours. How come "full charge capacity" is showing higher than some?
 

Attachments


Infiniteconstancy

macrumors regular
Nov 9, 2017
131
77
Hey all,

Just checked mine, have the same issue:
Screen Shot 2019-12-03 at 9.31.10 AM.png
So what is it that I have to? Charge it all the way? Is it not 100 because my laptop is currently at 89%?

Confused
 

phas3

macrumors 65816
Oct 5, 2008
1,112
16
Hey all,

Just checked mine, have the same issue:
View attachment 880575
So what is it that I have to? Charge it all the way? Is it not 100 because my laptop is currently at 89%?

Confused
let it discharge until the laptop dies, then plug it in up to 100% and keep it plugged in for another hour. I will note that I didn't have to do that with mine but that is the way to re-calibrate your battery.
 

Infiniteconstancy

macrumors regular
Nov 9, 2017
131
77
let it discharge until the laptop dies, then plug it in up to 100% and keep it plugged in for another hour. I will note that I didn't have to do that with mine but that is the way to re-calibrate your battery.
Wait...just realized mine does say design capacity 100%. Is that the one people have been having issue with?
 

Infiniteconstancy

macrumors regular
Nov 9, 2017
131
77
Hey all,

Just following up as you all are super knowledgeable - is the issue here for most the fact that the design capacity was not at 100% from the onset? I think mine is fine now then?
Screen Shot 2019-12-03 at 9.31.10 AM.png
 

jerryk

macrumors 603
Nov 3, 2011
5,167
2,533
SF Bay Area
Hey all,

Just following up as you all are super knowledgeable - is the issue here for most the fact that the design capacity was not at 100% from the onset? I think mine is fine now then?
View attachment 880776
I don't use Coconut Battery, by my question would be what does the Coconut Battery documentation or support say the values in Full Charge Capacity and Design Capacity mean? And how would they interpret your readings.
 

petterihiisila

macrumors member
Nov 7, 2010
86
36
Finland
I found that charging it with a low-powered charger (in my case a 45W USB-C monitor), the Full Charge Capacity will go down at the end of the day. But when I connect the MBP back to its own charger, it will keep charging after it reaches 100%, and after an hour or two, Full Charge Capacity is back to normal. If fact it went 100 mAH higher than the Design Capacity. I did no SMC/NVRAM resets.

That happened 3 times, before I received my LG 5k, which now has enough power to fully charge the MBP16. Now the top line doesn't get lower anymore.

I talked about this with Apple Support, and their opinion was that the reported numbers aren't to be taken seriously, if it's after using a charger that's not rated for the 16". And that it's not "real and lasting damage", it's just a reporting mishap. They've never had to replace batteries because of this. I know this isn't the cause of everyone's woes, but it could be the case for some people, because it's easy to connect to a USB-C monitor that can't produce enough juice.
 

marcinq

macrumors newbie
Nov 29, 2019
18
6
Design Capacity - the capacity that is "shown on the box" so in general the capacity they rate all of their batteries for.
Full Charge Capacity - actual measured fully charged battery capacity at current point in time.
 

Infiniteconstancy

macrumors regular
Nov 9, 2017
131
77
Yep let it die (run on battery until the Mac turns off), then plug it in and don’t unplug it until it’s full again + 1 hour more, to fully complete the charge (macOS 100% is not 100%, use coconut to be sure). That’s how mine was fixed. Since I sent the screenshot my capacity is back at 100% 😎
Which capacity? the full charge or design? Should both be 100%?
 

nickf1

macrumors member
Original poster
Jul 23, 2018
39
11
Sydney, AU
Which capacity? the full charge or design? Should both be 100%?
When you recharge, let it recharge all the way up to 100% (the charge indicator at the top needs to be 100%).
You have no control over the design capacity, it is what it is (like saying a bottle is 2L, you can't do anything about it, it is what it is). The issue here is that the "usable capacity" is sometimes reported lower than what it should be on a new battery. Cells will die during the life of the battery, but during the first weeks or month, you should have the same usable capacity as the battery is designed for (i.e. Full Charge Capacity equals Design capacity).
See below, this is now how my 16" behaves consistently:
1575846990776.png

The battery is charging at the moment and is not full yet - 92.7% (if you were calibrating, that's the number you want to wait to be at 100% before unplugging).
The design capacity is the same on all MBP 16": 8790 mAh.
The "Full charge capacity" is the usable capacity, and mine is now at 99.8% (8776 mAh), which is normal after 39 days (age of the battery).
1575847328453.png

Hope that clarifies things a bit.
 
  • Like
Reactions: Meuti