Batteries - ALL BATTERIES over time lose their ability to hold the same charge they did when new. There is no way to bring a battery whose battery health has declined to 85% back to new, except to replace the battery. I agree with lobsterghost1 you cannot get it to the original nominal 18 hours without a new battery. (The dead battery, that is; not your bad luck.) “The life of a lithium-ion battery is generally 500 cycles (about a year and a half). A battery cycle is measured by one full charge of 0 to 100. 14. tthomas612. • 3 yr. ago. 80% is where Apple says it need to be replaced. It’s very normal. Batteries can’t last forever. Most likely if you haven’t experienced lags or slowdowns then you may not experience anything except the battery dying quicker. It’s worth changing if you’re not going to upgrade soon. To create a report of the battery health on Windows 11, use these steps: Open Start. Search for Command Prompt, right-click the top result, and select the Run as administrator option. Type the To prolong the life of your iPhone battery, you can follow these tips and best practices: Optimize Battery Charging: Enable the "Optimized Battery Charging" feature on your iPhone. It helps reduce the wear on the battery by slowing down the battery aging process. 10. Only Charge to 85% to Optimize Battery Life. While charging your smartphone, you might have observed that the phone battery rapidly charges from 20% to 50%, yet it takes comparatively much longer when charging from 70% to 100%. As a result, charging efficiency reduces, and battery wear gets high when the smartphone approaches "full battery." Yet it depletes battery slower than my previous iPhone (6S) did at that capacity. I use MagSafe to charge it every day, and I have a MagSafe car charger & mount I use on my commutes. The longest it goes without charging is while I’m at work, and well, I don’t use it much then. According to Apple, a battery health of 80 percent is considered good for your iPhone. Normally, this percentage is reached at 500 complete charge cycles. One complete charge means having discharged 100 percent of your battery’s capacity. To illustrate what one complete charge means, let’s say you have used 80 percent of your battery today JIJ53Z.