iPhone Battery and Performance
Understand iPhone performance and its relation to your battery.
deliver an experience that is simple and easy to use is possible through a combination of advanced technologies and sophisticated engineering. One important technology area is battery and performance. Batteries are a complex technology, and a number of variables contribute to battery performance and related iPhone performance.
All rechargeable batteries are consumables and have a limited lifespan—eventually their capacity and performance decline. As batteries age, they can contribute to changes in iPhone performance. We created this information for those who would like to learn more.
About lithium-ion batteries
iPhone batteries use lithium-ion technology. Compared with older generations of battery technology, lithium-ion batteries charge faster, last longer, and have a higher power density for more battery life in a lighter package. Rechargeable lithium-ion technology currently provides the best technology for your device.
How to maximize battery performance
“Battery life” is the amount of time a device runs recharge. “Battery lifespan” is the amount of time a battery lasts until it replaces.
One factor affecting battery life and lifespan is the mix of things you do with your device. No matter how you use it, there are ways to help.
A battery’s lifespan is related to its “chemical age,” which is more than just the passage of time.
Also avoid charging or leaving the iPhone in hot environments, including direct sun exposure, for extended periods of time.
When batteries chemically age
All rechargeable batteries are consumable components that become less effective as they chemically age.
As lithium-ion batteries chemically age, the amount of charge they can hold diminishes, resulting in shorter amounts of time before a device needs recharging This referring to the battery’s maximum capacity—the measure of battery capacity relative to when it was new.
In addition, a battery’s ability to deliver maximum instantaneous performance, or “peak power,” may decrease.
When power pulling from a battery with a higher level of impedance, the battery’s voltage will drop to a greater degree. Electronic components require a minimum voltage to properly operate. This includes the device’s internal storage, power circuits, and the battery itself. The power management system determines the capability of the battery to supply this power, and manages the loads in order to maintain operations.
When the operations cannot support the full capabilities of the power management system, the system will perform a shutdown to preserve these electronic components. While this shutdown is intentional from the device’s perspective, it may be unexpected by the user.
Preventing unexpected shutdowns
With a low battery state of charge, a higher chemical age, or colder temperatures.
This performance management works by looking at a combination of the device temperature, battery state of charge, and battery impedance.
In cases that require more extreme forms of this performance management, the user may notice effects such as:
- Longer app launch times
- Lower frame rates while scrolling
- Backlight dimming (which can be overridden in Control Center)
- Lower speaker volume by up to -3dB
- Gradual frame rate reductions in some apps
- During the most extreme cases, the camera flash will be disabled as visible in the camera UI
- Apps refreshing in the background may require reloading upon launch
- Many key areas are not impacted by this performance management feature. Some of these include:
- Cellular call quality and networking throughput performance
- Captured photo and video quality
- GPS performance
- Location accuracy
For iOS 11.3 and later
iOS 11.3 and later improve this performance management feature by periodically assessing the level of performance management necessary to avoid unexpected shutdowns. If the battery health is able to support the observed peak power requirements, the amount of performance management will be lowered. If an unexpected shutdown occurs again, then performance management will increase. This assessment is ongoing, allowing more adaptive performance management.
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.
For iPhone 6 and later, iOS 11.3 and later add new features to show battery health and recommend when a battery replacing. These can be found in Settings > Battery > Battery Health.
Additionally, users can see if the performance management feature that dynamically manages maximum performance to prevent unexpected shutdowns is on and can choose to turn it off. This feature is enabled only after an unexpected shutdown first occurs on a device with a battery that has diminished ability to deliver maximum instantaneous power.
The effects of performance management on these newer models may be less noticeable due to their more advanced hardware and software design.
(Note: Devices updating from iOS 11.2.6 or earlier will initially have performance management disabled;
it will reenable if the device subsequently experiences an unexpected shutdown.)
All iPhone models include fundamental performance management to ensure that the battery and overall system operate as designation and internal components protection. This includes behavior in hot or cold temperatures, as well as internal voltage management. This type of performance management is required for safety and expected function, and cannot turn off.
Your battery’s maximum capacity
The Battery Health screen includes information on maximum battery capacity and peak performance capability.
Maximum battery capacity measures the device’s battery capacity relative to when it was new.
A battery will have lower capacity as the battery chemically ages which may result in fewer hours of usage between charges.
Depending upon the length of time between when the iPhone industry and activation, your battery capacity may show as slightly less than 100%.
designation A normal battery to retain up to 80% of its original capacity at 500 complete charge cycles when operating under normal conditions.
The one-year warranty includes service coverage for a defective battery. If it is out of warranty, Apple offers battery service for a charge.
As your battery health degrades, so can its ability to deliver peak performance. The Battery Health screen includes a section for Peak Performance Capability where the following messages may appear.
Performance is normal
When the battery condition can support normal peak performance and does not have the performance management features applied, you’ll see this message:
Your battery is currently supporting normal peak performance.
Performance management applied
When the performance management features apply, you’ll see this message:
This iPhone experienced an unexpected shutdown because the battery was unable to deliver the necessary peak power. Performance management applies to help prevent this from happening again. Disable…
Note that if you disable performance management, you can’t turn it back on. It will turn on again automatically if an unexpected shutdown occurs. The option to disable will also be available.
Battery health unknown
If iOS is unable to determine the device battery health, you’ll see this message:
This iPhone is unable to determine battery health. An Apple Authorized Service Provider can service the battery.
Performance management turned off
If you disable the applied performance management feature, you’ll see this message:
This iPhone has experienced an unexpected shutdown because the battery was unable to deliver the necessary peak power. You have manually disabled performance management protections.
the performance management features will re-apply. If the device experiences another unexpected shutdown,
The option to disable will also be available.
Battery health degraded
Battery condition deterioration, the below message will also appear and An Apple Authorized Service Provider can replace the battery to restore full performance and capacity.
This message does not indicate a safety issue. However, you may be experiencing more noticeable battery and performance issues. A new replacement battery will improve your experience.
Important Battery Message
If you see the message below, it means the battery in your iPhone is unable to be verified. This message applies to iPhone XS, iPhone XS Max, iPhone XR, and later.
Unable to verify this iPhone has a genuine Apple battery. Health information is not available for this battery.
iPhone battery warning
when the battery has a low capacity and the Performance Management doesn’t apply. This may indicate simply that you haven’t been in a situation where an unexpected shutdown could have taken place. However, the setting work when you play a graphically intensive game, and the battery was below 20 percent.