Your iPhone 13 battery is in good shape if Maximum Capacity is 80% or higher, there’s no service message, and the phone gets through your normal day. To check, open Settings > Battery > Battery Health & Charging. Apple designs the iPhone 13 battery to keep about 80% of its original capacity after 500 full charge cycles.
Maximum Capacity estimates how much charge the battery can hold compared with when it was new. The percentage beside the battery icon tells you how much charge remains right now. A phone can have 100% charge while its maximum capacity is lower than 100%.
Check battery health on iPhone 13
Apple's guide to batteries in iPhone 11 and later confirms the Battery Health & Charging route for iPhone 11, 12, 13, and 14.
- Open Settings. Tap the Settings app on your Home Screen or find it through iPhone Search.
- Tap Battery. This opens the battery page with current usage information and battery-related controls.
- Tap Battery Health & Charging. On iPhone 13, this is the page for the health estimate and charging options.
- Read Maximum Capacity. Note the percentage and the date you checked it. This estimate is relative to the battery's capacity when new.
- Read the performance and service information. Look for a normal-performance message, a recommendation for service, or a warning that battery information cannot be verified. Do not rely on the percentage alone.
For example, 88% Maximum Capacity means the battery's estimated capacity is lower than when it was new. It doesn't mean the phone is currently charged to 88%, and it doesn't mean you get exactly 88% of the original daily runtime. Apps, screen use, signal strength, temperature, and other conditions also affect runtime.
On iPhone 15 and later with iOS 17.4 or later, Apple documents Settings > Battery > Battery Health. That page can show maximum capacity, battery health, a replacement recommendation, cycle count, the manufacturing date, and the date the battery was first used.
The iPhone 13 Battery Health & Charging screen doesn’t show a built-in cycle count. A missing count doesn’t mean the battery is defective or that you need to install another app.
Understand the health numbers and messages
Maximum Capacity
Rechargeable batteries gradually lose capacity as they chemically age. Charging history, temperature, use, and elapsed time all contribute. A slightly lower reading than 100% does not by itself prove a defect, including on a phone that has spent time between manufacture and first activation.
For iPhone 14 and earlier, including iPhone 13, Apple says the batteries are designed to retain 80% of their original capacity at 500 complete charge cycles under ideal conditions. For iPhone 15 and later, its stated design figure is 80% at 1,000 cycles under ideal conditions.
What a charge cycle means
A cycle is cumulative use equivalent to the battery's full capacity, rather than every occasion you connect a cable. Using about half the capacity one day and another half later can add up to one cycle. Two brief charging sessions are not automatically two full cycles.
Performance information
The battery must deliver enough power for the task the phone is performing. Aging, low charge, and cold conditions can reduce its ability to provide peak power. Apple's battery and performance explanation describes how iOS manages performance to reduce unexpected shutdowns.
On iPhone 11 and later, Apple uses an automatic hardware and software system to manage these needs. Effects can include slower app launches, lower frame rates, dimmer backlighting, or other temporary changes. A dim screen alone does not establish a battery fault; brightness settings and temperature can also matter.
Service or significantly degraded health
A service recommendation indicates that battery replacement may improve capacity and performance. It is a reason to review service options, especially if runtime no longer meets your needs or shutdowns interrupt your work.
Apple says a significantly degraded-health message by itself does not indicate a safety issue. That is different from suspected physical damage. If the battery looks swollen or you suspect damage to the phone or battery, stop using it and contact Apple or an authorized service provider. Apple's iPhone safety guidance calls for trained battery repair.
Unable to verify the battery
If iPhone reports that it can’t verify the battery, its health information may be inaccurate. Note the exact message and have the battery checked instead of trusting the percentage shown.
Find what is draining the battery
Health describes the battery's condition; the usage page describes how energy was used. A phone with good maximum capacity can still drain quickly during heavy use, and an older battery can run down sooner even with unchanged habits.
On iOS 26 and later, Apple's rapid-drain guidance documents Daily Usage, which compares today's usage with the previous seven days. Older iOS versions can show different time ranges and graph labels; do not expect every screen to match the latest layout.
- Open Settings > Battery. Start with any suggestions or Insights above the usage chart. They can identify a setting or temporary activity worth reviewing.
- Read Daily Usage if it is available. Compare the reported usage with your actual day. A long navigation trip or extended video session can reasonably use more energy than a quiet day.
- Check App and System Activity Usage. Look at all the apps and system activity listed; the first app isn’t necessarily the problem.
- Tap View All Battery Usage for more detail. Choose the bar for a particular day and compare the listed activity with what you were doing at that time.
- Check an app's activity details. Note screen use, background activity, signal-related messages, notifications, or use while charging if those details appear.
An app’s battery-usage percentage is its share of usage during the selected period, not your remaining charge. The app at the top is often just the one you used most.
Reduce drain with the settings that fit the evidence
Use Low Power Mode when you need more runtime
On iPhone 13 and other iPhone 14-or-earlier models, open Settings > Battery and turn on Low Power Mode. On iPhone 15 and later, Apple's current route is Settings > Battery > Power Mode > Low Power Mode.
The battery icon turns yellow. The mode reduces or pauses features such as background refresh, email fetch, automatic downloads, some visual effects, and iCloud Photos. It is a temporary runtime aid; it does not increase Maximum Capacity.
Apple's Low Power Mode instructions confirm that it turns off after charging to 80% or higher. You can switch it off manually in the same location. Our Low Power Mode guide explains the controls and yellow icon.
Review the display
Lower brightness with the Control Center slider. To turn on automatic adjustment, open Settings > Accessibility > Display & Text Size > Auto-Brightness.
Check Settings > Display & Brightness > Auto-Lock if the screen remains on when you leave the phone idle. Choose a timeout that still works for your reading or other tasks. Record the previous choice so you can restore it.
For unexplained brightness changes, see why an iPhone keeps dimming. Increasing brightness or extending Auto-Lock may solve a visibility problem while increasing energy use, so consider both effects.
Review background refresh selectively
Open Settings > General > Background App Refresh to see the app switches. Turn off refresh for an app if you don’t need its content updated before you open it. Turn the switch back on if you miss the updates.
Music playback and location use are separate from Background App Refresh. Our Background App Refresh guide explains the global and per-app switches.
Apple’s battery performance recommendations cover the same settings.
What to do after an iOS update or new setup
Battery life can temporarily change while an update or setup finishes work in the background. On iOS 18 and later, Battery settings can show Insights such as ongoing update or device setup activity.
Apple advises waiting a few days and checking again if battery life is worse after an update.
Protect battery lifespan while charging
Apple's charging and maintenance guide explains that iPhone stops charging when full, so leaving it connected overnight is safe under appropriate charging conditions. You do not need to wait for the battery to reach zero before recharging it.
Optimized Battery Charging reduces the time spent fully charged by learning your routine. On iPhone 13, find it under Settings > Battery > Battery Health & Charging. It is different from the charge-limit setting on newer models; an iPhone 13 doesn’t have every newer iPhone charging control.
On iPhone 15 and later, Settings > Battery > Charging offers a limit from 80% to 100% in 5% increments. Optimized Battery Charging is available when that limit is 100%. A phone with a lower limit can occasionally charge fully to maintain accurate charge estimates. Apple's charging-optimization guide explains these controls. Neither the chosen limit nor a temporary charging pause is a Maximum Capacity measurement.
Avoid using or charging the phone in ambient temperatures above 95°F (35°C), which Apple says can permanently reduce battery lifespan. Cold can temporarily shorten runtime. Software may also limit charging above 80% when battery temperatures are too high; that is not proof of a capacity reading of 80%.
Keep the phone and charger ventilated. Do not charge under a pillow or blanket. If a case causes excessive warming during charging, Apple's battery-care guidance recommends removing it. Use an appropriate undamaged charging cable and adapter.
When to consider battery service
Consider service when the health page recommends it, the battery no longer lasts through your usual tasks, or unexpected shutdowns keep happening. A replacement can restore an aging battery's capacity and performance; it won't fix heavy app use, poor signal, or a software problem.
Have Apple or an authorized service provider check the device and current service options. Pricing and coverage depend on the model, location, and your plan or warranty, so check your own eligibility instead of using an old price list.
Frequently asked questions
Is 80% battery health the same as an 80% charge limit?
No. Maximum Capacity is an estimate of the battery's condition relative to new. A charging limit restricts the current charge on supported models. The same number can refer to different things in these settings.
Will Low Power Mode improve battery health?
It reduces current energy use to help a charge last longer. It does not restore capacity already lost through battery aging. Read Maximum Capacity and the service message separately.
Does my iPhone 13 support Adaptive Power?
No. Apple's current supported-device list for Adaptive Power starts with selected newer hardware, including iPhone 15 Pro models. Updating an iPhone 13 to an iOS version with Daily Usage does not give it Adaptive Power support.
Should I replace the battery as soon as the reading drops?
A small decline alone is not a complete diagnosis. Consider the service recommendation, your runtime needs, and symptoms such as repeated shutdowns. Use Apple's model-specific design figures as context, without treating them as a guaranteed expiry date.
Matthew Burleigh is the founder, head writer, and editor of Solve Your Tech, which he launched in 2012. He has written technology tutorials since 2008 and worked in IT since 2003, including small-business support, IT management, and consulting. He holds Bachelor’s and Master’s degrees in Computer Science from Arizona State University.
Matthew writes practical guides for Windows, iPhone and iPad, Microsoft Office, Outlook, Google apps, and Android. Solve Your Tech’s guides are checked step by step against the device or app maker’s own documentation and tested on his own devices whenever he has the hardware or software, with clear steps, sources, and update dates.
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