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Other Do all iPhones stay at 100% for an unrealistic length of time?

T

tonybarnaby

macrumors 68020
Original poster
Dec 3, 2017
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This is my first one, so I'm not sure. I ran my phone down to 10% as a test, and it definitely dropped a lot faster the closer it got to empty. I wouldn't say exactly at 50%, but from 40% or so on down, it seemed to really drop quicker.

If you take your phone off the charger at 100%, can you get 20-30 minutes of usage before it hits 99%? I have struggled with battery OCD for a while now. I'm finally just charging to 100% and forgetting about it. $80 for a new battery is a good deal, but I may utilize the IUP, so I will not ever deal with capacity loss.

It just has me scratching my head why iPhones seem to be programmed to stay at 100% for an unrealistic period of time. I've seen it on battery drain tests and heard people talk about it, so I finally checked it out for myself.

I got nearly 30m of usage from 100-99%. Most days my phone stays at 100% from the fine I leave work until my first break, which is 4 hours later. There's some usage time in there too. Zero chance any phone can not lose a single % over 4h of standby plus 10-15m of actual usage.

My theory is that when an iPhone goes from 100-99%, it's actually closer to 96 or maybe 97%, relative to how fast it drops in the lower percentages.

My car takes forever to get to 1/2 tank, and then drops like a stone. That's predictable because of how the float in the tank operates. Why has apple programmed the iPhone to stay at an jndicated 100% for so long? I'd rather it stay linear the entire way.
 
MacDawg said:
The battery indicators are not precise and are only meant to be a general guide, not an absolute reckoning
That's one reason I turned off my battery percentage a few years ago and haven't worried about it since
Click to expand...
I don't worry about it because I'll never come close to draining it in a single day, but it bugs me why they obviously programmed it to show 100% for so long. What could they possiblity gain? Maybe for the people who need to see 100% to prevent anxiety? Just weird.
 
MacDawg said:
I personally don't think it is deliberately programmed somehow to show 100% for an extended period to deceive users
Click to expand...
It's probably not to deceive anyone, but it's confusing why they would program it like this. I have never experienced this on any phone before.
 
Yes. My 4,5,6, and 7 all have stayed at 100% for the first 30-60 minutes of usage depending on what you are doing.
 
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Measuring battery capacity accurately is difficult. The level of power remaining over time isn’t a perfectly straight line and it doesn’t stay the same throughout the life of the battery. I just turned the percentage indicator off and I charge my phone when I can.
 
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This is pure speculation on my part, but I think that it reads 100% when the battery is fully enough that it won't accept additional charge. Remember that it is designed to prevent overcharging, which is why you can safely leave your iPhone plugged in over night. So rather than meaning that the battery is literally 100% full, I think it just means it's in a certain range of fullness that can be called "full" for all intents.

Evidence of this that I've seen is that at times I've unplugged my charging phone at say 98%, and then plugged in back in immediately and it will read 100% and not charge, so it seems that "100%" can actually mean the high 90s.
 
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I believe 100% has a large range for battery wear reasons. The phone lets the charge deplete a bit instead of constantly charging.
 
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When I charge my phone until, for example 88%, it holds that percentage for the same amount of time as when it’s at 100%, so for around 30 minutes of usage. When I restart the phone immediately after charging it to any percentage below 100%, there’s always a couple percent added afterwards.
 
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Love the comments. I never paid attention to it so it must not be true.
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joeblow7777 said:
This is pure speculation on my part, but I think that it reads 100% when the battery is fully enough that it won't accept additional charge. Remember that it is designed to prevent overcharging, which is why you can safely leave your iPhone plugged in over night. So rather than meaning that the battery is literally 100% full, I think it just means it's in a certain range of fullness that can be called "full" for all intents.

Evidence of this that I've seen is that at times I've unplugged my charging phone at say 98%, and then plugged in back in immediately and it will read 100% and not charge, so it seems that "100%" can actually mean the high 90s.
Click to expand...

But the OP says the issue is the phone stays at 100% for a long time. So whether your phone reads 98% or 100% at a full charge is irrelevant. After your unplug it how long does it stay at 100% or 98% for that matter?
 
bopajuice said:
Love the comments. I never paid attention to it so it must not be true.
[doublepost=1517203457][/doublepost]

But the OP says the issue is the phone stays at 100% for a long time. So whether your phone reads 98% or 100% at a full charge is irrelevant. After your unplug it how long does it stay at 100% or 98% for that matter?
Click to expand...

The point I’m making is that yes, it says 100% for an abnormally long time once it’s unplugged, but I suspect that’s simply because the software in effect rounds up when it’s near enough to a full charge.

Perhaps I didn’t explain very well.
 
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I can tell you exactly why it stays at 100% for longer than normal.

The first 5% of battery percent are not linear, after than, the following 95% is "kind of".

When iOS is reporting 100%, your battery is anywhere between 95-100%. Once it reaches 94%, it will report 99% and so on. These are the percent differences.

Reporting v. Actual.
100% = 95%
50% = 47.5%
25% = 23.75%
10% = 9.5%
1% = .95-1%

I have spent years tracking the battery's mAh to determine the drain rate. This applies to all iOS and macOS devices. I have posted more detailed posts in the past with screenshots to actually show this, but its been quite a while and I have no idea where to begin to look for them. But hopefully this helps. @BigMcGuire would probably agree to these numbers as well. He has seen my much larger post.

The reason why Apple does this is because once the battery reaches 100% it stops charging until the battery reaches 97%, then it charges back up to 100%. People would worry why their phone was dropping below 100% while it was still plugged in, so they made it a "fail-safe" percent. When it drops down to 97%, it is still showing 100% so it does not worry the user.
 
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Mlrollin91 said:
I can tell you exactly why it stays at 100% for longer than normal.

The first 5% of battery percent are not linear, after than, the following 95% is "kind of".

When iOS is reporting 100%, your battery is anywhere between 95-100%. Once it reaches 94%, it will report 99% and so on. These are the percent differences.

Reporting v. Actual.
100% = 95%
50% = 47.5%
25% = 23.75%
10% = 9.5%
1% = .95-1%

I have spent years tracking the battery's mAh to determine the drain rate. This applies to all iOS and macOS devices. I have posted more detailed posts in the past with screenshots to actually show this, but its been quite a while and I have no idea where to begin to look for them. But hopefully this helps. @BigMcGuire would probably agree to these numbers as well. He has seen my much larger post.

The reason why Apple does this is because once the battery reaches 100% it stops charging until the battery reaches 97%, then it charges back up to 100%. People would worry why their phone was dropping below 100% while it was still plugged in, so they made it a "fail-safe" percent. When it drops down to 97%, it is still showing 100% so it does not worry the user.
Click to expand...
That's kind of what I was thinking. If I can get 30m of usage from 100-99, I assumed it was actually at 97% or 96%. Considering the phone uses 1% every 8-10m of usage, it made sense to me.
 
tonybarnaby said:
I don't worry about it because I'll never come close to draining it in a single day, but it bugs me why they obviously programmed it to show 100% for so long. What could they possiblity gain? Maybe for the people who need to see 100% to prevent anxiety? Just weird.
Click to expand...

The gas gauge on my Audi does the same thing. The whole point is that the gauge shows an approximate quantity of power and is not accurate. Ignore it if it bothers you.

I thought you were forcing yourself to not be OCD about the battery anymore.

https://forums.macrumors.com/thread...stop-being-ocd-about-my-battery-life.2097856/
 
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I'm showing my age here, but the old Nokia phones (like the 3310, etc.) used to do this too; it showed four bars (100%) for about 6 days, but once the first bar went, the other three would go pretty quickly, and you knew you only had about 36(!) hours left before you'd need to charge again. Anyone remember those days? lol
 
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tonybarnaby said:
This is my first one, so I'm not sure. I ran my phone down to 10% as a test, and it definitely dropped a lot faster the closer it got to empty. I wouldn't say exactly at 50%, but from 40% or so on down, it seemed to really drop quicker.

If you take your phone off the charger at 100%, can you get 20-30 minutes of usage before it hits 99%? I have struggled with battery OCD for a while now. I'm finally just charging to 100% and forgetting about it. $80 for a new battery is a good deal, but I may utilize the IUP, so I will not ever deal with capacity loss.

It just has me scratching my head why iPhones seem to be programmed to stay at 100% for an unrealistic period of time. I've seen it on battery drain tests and heard people talk about it, so I finally checked it out for myself.

I got nearly 30m of usage from 100-99%. Most days my phone stays at 100% from the fine I leave work until my first break, which is 4 hours later. There's some usage time in there too. Zero chance any phone can not lose a single % over 4h of standby plus 10-15m of actual usage.

My theory is that when an iPhone goes from 100-99%, it's actually closer to 96 or maybe 97%, relative to how fast it drops in the lower percentages.

My car takes forever to get to 1/2 tank, and then drops like a stone. That's predictable because of how the float in the tank operates. Why has apple programmed the iPhone to stay at an jndicated 100% for so long? I'd rather it stay linear the entire way.
Click to expand...

You are assuming that the battery discharges linearly. The battery Guage is self learning, based on prior charge and discharge cycles.

Wait until that new battery feature is released in 11.3. Then the ugliness of the nonlinear discharge rate will rear it's head.

You want consistent performance from a smartphone. But not all phones are equal. The newest iPhone models use a unique set of high performance power CPU cores and efficient low power cores. The battery was redesigned for best longevity.

As your phone matures, you will see the 100 to 75 percent type decrease. You will also see the OS throttle the CPU for best battery life, in standby mode.
 
Mlrollin91 said:
I can tell you exactly why it stays at 100% for longer than normal.

The first 5% of battery percent are not linear, after than, the following 95% is "kind of".

When iOS is reporting 100%, your battery is anywhere between 95-100%. Once it reaches 94%, it will report 99% and so on. These are the percent differences.

Reporting v. Actual.
100% = 95%
50% = 47.5%
25% = 23.75%
10% = 9.5%
1% = .95-1%

I have spent years tracking the battery's mAh to determine the drain rate. This applies to all iOS and macOS devices. I have posted more detailed posts in the past with screenshots to actually show this, but its been quite a while and I have no idea where to begin to look for them. But hopefully this helps. @BigMcGuire would probably agree to these numbers as well. He has seen my much larger post.

The reason why Apple does this is because once the battery reaches 100% it stops charging until the battery reaches 97%, then it charges back up to 100%. People would worry why their phone was dropping below 100% while it was still plugged in, so they made it a "fail-safe" percent. When it drops down to 97%, it is still showing 100% so it does not worry the user.
Click to expand...

Perfect post! I agree! Yep - I've had those phones and electronic devices where, soon as you unplug them, poof, it hits 99%. It may be the "real" battery capacity at the moment but it's going to cause a lot of OCD people like me to keep plugging in our phones over and over needlessly.

The Apple Watch does this by a HUGE magnitude --- putting the watch on the charger, it will charge for up to two hours after hitting 100%, then remain at 100% for 8 hours after taking the watch off the charger (as of 4.2.2). I love it.

@Mlrollin91 is 100% correct. You can see the actual percentage by plugging into CoconutBattery. These batteries are fascinating and fun to observe. :)
[doublepost=1517239132][/doublepost]
Laowai184 said:
I'm showing my age here, but the old Nokia phones (like the 3310, etc.) used to do this too; it showed four bars (100%) for about 6 days, but once the first bar went, the other three would go pretty quickly, and you knew you only had about 36(!) hours left before you'd need to charge again. Anyone remember those days? lol
Click to expand...

Yep, I used to use one of those ... I wonder if the old Ni-MH batteries from those days are why I'm so obsessed with my battery now because you were supposed to drain them completely before charging them back up so you'd always have the situation where you were going on a trip but had to drain your phone first or having your phone die when you didn't want it to... lol. Pretty sure a factor into why I have a battery OCD now (a good one).
 
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BigMcGuire said:
Yep, I used to use one of those ... I wonder if the old Ni-MH batteries from those days are why I'm so obsessed with my battery now because you were supposed to drain them completely before charging them back up so you'd always have the situation where you were going on a trip but had to drain your phone first or having your phone die when you didn't want it to... lol. Pretty sure a factor into why I have a battery OCD now (a good one).
Click to expand...

Getting home with a shiny new toy and having to wait 12 hours while it charged for the first time was bloody annoying!!
 
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