Does the iPhone’s Battery Charging Limit Really Preserve Battery Health?
Your iPhone’s battery is a consumable product, one that degrades a little bit each day. The rate of degradation can vary depending on a lot of factors:
Ambient temperature.
Method of charging.
Power hungry apps you run on your phone.
In other words, heat is the biggest culprit for both battery life and battery health. The more you can avoid it, the longer and healthier your battery will be. It will be able to perform at a high level for a longer period of time, not causing your iPhone to slow down or to shut down.
I have had my iPhone 15 Pro Max for exactly one year set to the 80% charging limit and I wanted to explain my battery health results.
My battery charging habits
I charge my iPhone 90-95% of the time wirelessly with MagSafe or Qi2 charging, and 5-10% of the time via a USB-C cable. Note that I only used Qi2 wireless charging, which includes magnets that mimic MagSafe. Both bedrooms that I use for charging are pretty cold and stay around 70-77 degrees year long. It is mainly at work when I use wired charging, also in a room hovering around 70 degrees. The last 2 weeks I was traveling overseas, so I resorted strictly to wired charging.
My battery settings
From the very beginning I had set my iPhone to an 80% battery charging limit, which means the phone stops charging at 80%. Occasionally the phone does charge to 100% on its own to recalibrate the capacity, but those special days were few and far in between. I was fine with 80% charge most of the time and never really ran out of juice. I have another MagSafe charger in our kitchen area, so I would always get a battery boost whenever I needed it.
My phone habits
My iPhone habits are pretty typical, consisting mainly of social media browsing, Safari, Camera, YouTube, email, PocketCasts, etc. I don’t game much at all on my iPhone, and when I do I play very basic games that don’t really tax the phone and cause it to dim or overheat (thank you Crossy Road and Alto’s Odyssey!). I also use the flashlight, A LOT.
I’m also like many people who sometimes just unlocks their iPhone for no real reason, only to lock it back again. ADHD is alive and well.
I have auto-brightness disabled almost all the time and tend to keep the brightness higher than what Apple would recommend. The Always-On display is also a favorite feature of mine that I use, with the wallpaper and notifications active.
I did run developer and public betas on my iPhone all year long.
Final Battery Health and Conclusion
With all these parameters in mind, I was still able to achieve a 99% battery health, with 296 cycle counts. I attribute most of that success to the 80% charge limit. Juli Clover from MacRumors also tried this experiment and got 94% battery health with 294 cycles. Other MacRumors staff members who did not have their battery charge set to 80% had the following results:
Current capacity: 87%. Cycles: 329
Current capacity: 90%. Cycles: 271
I am just one test subject, but based on what I have seen, limiting your battery charging limit can definitely preserve your battery for many years to come. Good charging habits are also key in keeping the battery health at its maximum by using wired charging and efficient wireless solutions such as MagSafe and Qi2 charging.