iPhone XS shutting down with 30%+ battery remaining

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Level 1

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iPhone XS shutting down with 30%+ battery remaining

This just started in the last couple of weeks. I'll be using the phone, battery life is supposedly at 30% or more, and the phone will turn off. To restart it, I have to plug it in and the when it turns on the battery life will read anywhere from 12% to 14%, and then occasionally it will turn back on and say there's 35% to 40% battery. In either case, the phone hasn't been on the charger long enough to charge significantly at all.

I was trying to run the phone down to no battery left on the battery level, but it won't go below 12% before it shuts off and won't restart without plugging in. Battery health says fine and says it still has 93% or original capacity. No other issues on the phone. Phone isn't even 2 years old, has been well taken care of, and is in good physical condition.

What's next here? Back up everything to the computer and do a hard/factory reset? A little frustrating as the was my first iPhone after years of Android. Really liked the integration with my MacBook and after having such good luck with the computers, thought the phones would be just as reliable.

iPhone XS, iOS 14

Posted on May 24, 2021 8:24 PM

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Answer 1

Top-ranking reply

nwguitar Author

Level 1

9 points

May 29, 2021 8:26 AM in response to LD150

Sure, there's no arguing that batteries chemically age over time, but where I disagree is that after 18 months it's acceptable for a battery to become totally unreliable, and that the only cure is a new battery.

The "don't charge past 80%" was also a method endorsed by Apple, but I didn't pose my original question to discuss physics, chemistry, and charging approaches. The question was is there a way to recalibrate the battery level software so it more accurately reads the battery capacity and prevents flukey shutdowns at 30%. Responses have not been helpful.

To get back to that question, I seem to have gotten the phone battery recalibrated. Was able to run the battery down to 0% before it shutdown and then charged to 100%. Believe it was one of two things. The first thing I noticed was when I went to make a backup of the phone storage on my computer, the computer downloaded diagnostic data. Don't think that did anything but it was a new observation for me. Guessing the MacBook just downloaded that info from the phone, and didn't doing any diagnostics. Next thing I did before doing a factory reset was update software to 14.6. After those two things, I was able to run the battery to 0 without it shutting off prematurely. It's been doing fine ever since, and not shutting down with 30% battery left.

So guessing the software update got things straightened up for me. Whether it was a bug fix in 14.6, or just resetting the phone data on battery capacity in parallel to the software update, I'm not sure, but problem solved. After all that, the battery does now say 91% capacity but still is able to maintain peak output.

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Answer 2

LD150

Level 10

91,471 points

May 25, 2021 1:49 AM in response to nwguitar

Two year old battery should not still be 93% unless you were bery lucky.

I would say it needs a new battery.

Take it or send it for repair

https://support.apple.com/iphone/repair/service

Anything other than Screen or Battery may be a replacement phone and the price is in the article, depending on your warranty or AppleCare+ status.

You can see additional service information within the following article:

Get your iPhone, iPad, or iPod touch ready for service - Apple Support

Battery Repair

iPhone Battery & Power Repair

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Answer 3

nwguitar Author

Level 1

9 points

May 25, 2021 5:28 PM in response to LD150

Why would the battery capacity number on the phone be incorrect? Have no reason not to trust the information from the phone. It squares with the ranges I've seen others report and the battery is supposed to be able to function at peak performance.

FWIW, I've been pretty judicious about charging the phone, typically keeping the battery between 20% and 80% charged.

Given the dying at 30% and the typical charging range, it would seem the software/hardware needs to be recalibrated, as is in when it says 30% it's closer to zero. Is there a way to do this recalibration? Is there any substance to say the procedures here:

https://www.iphonetricks.org/how-to-fix-iphone-battery-percentage-bug-in-ios-14/

Or will a factory reset potentially help at all?

I just have a hard time buying into a less than 2 year old phone needing a new battery.

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Answer 4

LD150

Level 10

91,471 points

May 26, 2021 12:06 AM in response to nwguitar

That procedure (which can work but is now not recommended) requires depletion to zero. Your phone will not get to zero.

In my own view, not shared by all others, if you never charge to 100 % and never run it below 20% how on earth is it supposed to estimate total mAh capacity?

What is the point of being proud of 93% after 2 years if you only ever use 60% of that?

If you had charged it at night all night on optimised charging like they are designed to, and run it to 5% or less occasionally, it may not have done this.

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