Q: Why do I have occasional days where my iPhone battery is suddenly low on power by midday when I鈥檓 not doing anything unusual?
A: The single biggest issue for every smartphone user is battery life, and no matter what type of device you have, it鈥檚 going to diminish over time.
How Old Is It?
Whenever I鈥檓 asked this question, I always start by focusing on the age of the device. If it鈥檚 relatively new, it鈥檚 probably related to app usage; if it鈥檚 older, it鈥檚 probably suffering from diminished battery capacity.
Start by checking the battery鈥檚 maximum capacity, which is a measure relative to when it was new or at 100%.
Tap Settings, then Battery, then Battery Health to get your current status. If it鈥檚 under 80%, it may be time to replace the battery. If it鈥檚 well above 80%, your issues are probably app usage related.
Chemical Age
All rechargeable batteries are considered consumables, meaning there鈥檚 a finite limit to their usefulness. As time goes on, the physical age isn鈥檛 as important as the “chemical age” of the battery, which is primarily determined by charge cycles and how it鈥檚 been cared for.
Charge Cycles
Apple鈥檚 guideline for battery life span is based on 500 complete charge cycles. A charge cycle is when you鈥檝e discharged 100% of the battery鈥檚 capacity, but not necessarily in one day. For instance, if your battery level is at 50% when you recharge on two consecutive days, that would represent one charge cycle. If you are down to 25% every day when you charge, you鈥檙e using just over five charge cycles a week.
After 500 charge cycles, your battery will likely be at or near 80% capacity. For most users, that鈥檚 two to three years of regular usage.
Temperature鈥檚 Impact
One of the easiest ways to quickly increase the chemical age of your battery is through exposure to high ambient temperatures.
Temperatures above 95 degrees can permanently damage the battery鈥檚 capacity, which can be a constant challenge if you live in a warm climate.
Another big thing to avoid is charging your phone when it鈥檚 hot, which can further damage the battery.
Your App Usage
Which apps you use and how you use them can have a big impact on daily battery life. Apple makes it easy to see this by going to Settings, then Battery, and scrolling down to the list of apps by battery usage.
The default is “Last 24 Hours” but you鈥檒l better understand your regular usage patterns by tapping “Last 10 Days.”
The app that uses the most battery power will be at the top of the list along with the percentage of battery consumption. This should reflect the apps you use the most, but there鈥檚 more helpful information available if you tap the “Show Activity” option.
This will give you more details, including how many hours or minutes you鈥檝e used the app and how much of that time was in the background.
If the background usage is very high, you should start manually shutting down those apps when you aren鈥檛 using them.
Battery Replacement
If your capacity is below 80%, Apple provides a relatively affordable replacement option for most current iPhone models ranging between $89 to $99. To get an estimate on your exact device, .
Ken Colburn is founder and CEO of . Ask any tech question on or .
