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Apple on Tuesday released iOS 12.1 following six weeks of beta testing. As mentioned in the release notes, the software update extends Apple's performance management feature to the iPhone 8, iPhone 8 Plus, and iPhone X.

iphone-x-battery-800x419.jpg

From the release notes:
Adds a performance management feature to prevent the device from unexpectedly shutting down, including the option to disable this feature if an unexpected shutdown occurs, for iPhone X, iPhone 8 and iPhone 8 Plus.
Apple has reflected this change on its iPhone Battery and Performance website, noting that performance management "may be less noticeable" on those iPhone models due to their "more advanced hardware and software design."

The performance management system was first enabled in iOS 10.2.1, but it was limited to the iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, iPhone SE, iPhone 7, and iPhone 7 Plus until yesterday's release of iOS 12.1.

Last December, Apple did mention that the design of the iPhone 8, iPhone 8 Plus, and iPhone X allows for a "different" performance management system that "more precisely" prevents unexpected shutdowns, but prior to iOS 12.1, no performance management feature of this kind had been enabled on the trio of iPhones:
iPhone 8 and later use a more advanced hardware and software design that provides a more accurate estimation of both power needs and the battery's power capability to maximize overall system performance. This allows a different performance management system that more precisely allows iOS to anticipate and avoid an unexpected shutdown. As a result, the impacts of performance management may be less noticeable on iPhone 8 and later. Over time, the rechargeable batteries in all iPhone models will diminish in their capacity and peak performance and will eventually need to be replaced.
Why is Apple slowing down some iPhone models if necessary?

From our January 2018 article What to Know About Apple Slowing Down iPhones to Prevent Unexpected Shutdowns:
iPhones, like many other consumer electronics, are powered by lithium-ion batteries, which have a limited lifespan. As the battery in your iPhone ages, its ability to hold a charge slowly diminishes.

A chemically aging battery can also have increased impedance, reducing its ability to provide a sudden burst of power when demanded by other components in an iPhone, such as the CPU and GPU. A battery's impedance will also temporarily increase when it has a low charge and/or in cold temperatures.

A battery with a high enough impedance may be unable to provide power quickly enough to the iPhone when needed, and Apple safeguards components against the drop in voltage by shutting down the device.

Apple recognized that iPhones unexpectedly shutting down on users is not a good experience, and starting with iOS 10.2.1, it quietly implemented a power management feature to prevent these shutdowns. The update was released in January 2017, and a month later, Apple said it saw a major reduction in shutdowns.
The performance management feature can be disabled if desired in the Settings app, under the Battery Health menu. At this time, the feature does not appear to extend to the new iPhone XS, iPhone XS Max, or iPhone XR.

Article Link: iOS 12.1 Extends Battery-Related Performance Management Feature to iPhone 8, iPhone 8 Plus, and iPhone X
 
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BulkSlash

macrumors 6502
Aug 20, 2013
267
697
Totally fine with me. Better than a phone becoming unusable, but of course they've should've been disclosing it and allowing users to toggle it on and off from the beginning.

I'd be fine with it if the battery lasted more than a single year before needing it. In fairness it's probably only a small group where the battery is bad enough to need throttling but even so, for the price of the phone the batteries should have better longevity.
 

1144557

Cancelled
Sep 13, 2018
925
2,413
I'd be fine with it if the battery lasted more than a single year before needing it. In fairness it's probably only a small group where the battery is bad enough to need throttling but even so, for the price of the phone the batteries should have better longevity.

Blame battery tech not Apple. Apple didn't invent lithium-ion batteries. They simply chemically degrade over time due to charge and discharge cycles. No devices (not just smartphones) are immune from battery degradation. Same reason your cordless dustbuster/stick vac battery wont hold a charge after a certain amount of time; it has nothing to do with the device the battery is in but number or charge/discharge cycles.

Seems like a problem that could have been solved if Apple bothered to ship their phones with an appropriately sized battery...

Huh? What does battery capacity have to do with number recharge cycles and chemical degradation of a lithium-ion battery? ALL batteries degrade over time.


"The lithium-ion battery works on ion movement between the positive and negative electrodes. In theory such a mechanism should work forever, but cycling, elevated temperature and aging decrease the performance over time. Manufacturers take a conservative approach and specify the life of Li-ion in most consumer products as being between 300 and 500 discharge/charge cycles."

Temperature 40% charge 100% charge
0°C 98% (after 1 year) 94% (after 1 year)
25°C 96% (after 1 year) 80% (after 1 year)
40°C 85% (after 1 year) 65% (after 1 year)
60°C 75% (after 1 year) 60% (after 3 months)

So charge cycles and ambient temperature make a HUGE difference in life of a battery. And since no one keeps their devices at 0°C (freezing point) and factoring most charge the battery to 100% each time, a 20% degradation after 1 year per the chart is proven by science. It's not simply "Apple said"
 
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neliason

macrumors 6502
Oct 1, 2015
452
952
Apple’s management of batteries across devices is odd. Why doesn’t iPad have a low power mode? More importantly why doesn’t iPad have a battery health report? These are important features for all devices and not just the one’s Apple decides to surreptitiously tinker with.
 

gnipgnop

macrumors 68000
Feb 18, 2009
1,824
2,334
This continues to be one of the dumbest controversies about an Apple product ever. It's like complaining about the anti-lock brakes on your car as if it's a conspiracy by auto manufacturers to prevent you from using the brakes to their full extent.
 
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tromboneaholic

Suspended
Jun 9, 2004
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Clearwater, FL
I'd be fine with it if the battery lasted more than a single year before needing it. In fairness it's probably only a small group where the battery is bad enough to need throttling but even so, for the price of the phone the batteries should have better longevity.
My iPhone X battery is still at 100% maximum capacity nearly a year later.
 

Apple Outsider

macrumors newbie
Oct 31, 2018
4
1
If this is limited to aging batteries, maybe someone can explain why my recently replaced Apple battery has crashed on me twice already?

zPPzv5E.jpg
 

Dwalls90

Contributor
Feb 5, 2009
5,283
3,861
I do question why this isn't an issue in other Apple products. Also, was this an issue with iPhones prior to the 6? Wonder what changed.. was it quality of batteries?

Before I get flamed, I'm not disagreeing with the fact that all hardware are consumable products that "breakdown" over time due to chemistry. More just highlighting inconsistencies across time or products.
 

gnipgnop

macrumors 68000
Feb 18, 2009
1,824
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If this is limited to aging batteries, maybe someone can explain why my recently replaced Apple battery has crashed on me twice already?

It's never been limited to aging batteries. Apple provided three scenarios where the phone battery might not be able to supply the proper voltage: age of the battery, cold conditions, low charge. Cold conditions and low charge can occur with a brand new battery. That's true of any phone-sized lithium ion battery in any brand of mobile phone.
 
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joueboy

macrumors 68000
Jul 3, 2008
1,576
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This feature should be user controlled not Apple deceiving some customers into buying a new phone when they can just have a battery replaced to fix the problem. All this battery degradation is fully understandable and shouldn't be used as an excuse to slowdown and shutting down phones. Apple can intergrate a charge cycle info into iOS if they wanted to, to show people they use their phone a lot and they charge it too much. Everybody understands it, that's a law of nature the more you use I the faster you wear it down. Not a lame excuses how lithium technology blah, blah, blah... It doesn't matter even old battery technology or future battery technology this will have the same effect, eventually you gonna wear it down and it depends how much you use them. It may last longer in the future but eventually you gonna wear it down and it needs a replacement.
 
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Xenomorph

macrumors 65816
Aug 6, 2008
1,375
783
St. Louis
Apple’s management of batteries across devices is odd. Why doesn’t iPad have a low power mode? More importantly why doesn’t iPad have a battery health report? These are important features for all devices and not just the one’s Apple decides to surreptitiously tinker with.

The worst part of this is that even though they don't provide battery information on devices like iPhone 5S or any iPad, iOS 12 removed any ability for battery apps to check battery information.

While my iPhone 6S, 8, and XS have built-in battery info, my iPhone 5S, iPad Air 2, and iPad Pro all lost the ability to see their battery info on-device. I have to plug them into Windows or macOS and run iBackupBot or CoconutBattery.
 

BaccaBossMC

macrumors regular
Jul 8, 2016
204
731
NC, USA
I'm fairly certain that the 'maximum capacity' information is incorrect. My 6s Plus claims it has 84% remaining, but it gets about half of the battery life that it did when I bought it, and I bought it used.
 

ssl0408

macrumors 65816
Sep 22, 2013
1,226
534
New York
The iPhone X battery is crap. I’m down to 90% after 10 months. I’m thinking to get it replaced before the prices go back to $69.
 

Apple Outsider

macrumors newbie
Oct 31, 2018
4
1
This continues to be one of the dumbest controversies about an Apple product ever. It's like complaining about the anti-lock brakes on your car as if it's a conspiracy by auto manufacturers to prevent you from using the brakes to their full extent.

This is Apple’s attempt to mitigate problems caused by a FAULT. It’s not normal behaviour.

Imagine if your car developed a fault with the engine and the manufacturer, to stop it from ceasing working altogether, put a limit so that it could no longer go faster than 30 mph.

It’s a FAULT. It’s not supposed to be limited in every day use. It should be fixed.

This was not a problem in earlier iOS devices, nor is it one in later devices.

It’s also not dumb to complain that your phone becomes janky and unresponsive in everyday use (which is what happens when the power management feature is enabled).

Going into demanding apps, like CityMapper takes a LOT longer while power management is enabled.
 
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DNichter

macrumors G3
Apr 27, 2015
9,336
11,022
Philadelphia, PA
Good, they should implement the feature. I know I'd rather them throttle my phone instead of it shutting down due to a bad battery. Now that you have battery health available to you, you can see this and make the decision to either replace the phone or the battery.
 

largefarrva

macrumors 6502a
Jun 30, 2012
901
364
Another person here with an X and the only option I see is low power mode. Nothing to indicate being able to disable this feature. Maybe it doesn't actually apply to the X?
 
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