Imagine a scenario where your iPhone battery is running low, and there's not a charger in sight. But in your back pocket is an extra battery. With a quick pull, the empty battery pops off the iPhone, and the fully charged backup snaps onto the device. Boot up iOS and you're back in business. Not long ago, most cellular phones came with fully removable batteries.
Hidden among the many changes and improvements to iOS 13 is a feature Apple calls Optimize Battery Charging. All rechargeable batteries have a limited lifespan, which means over time their capacity to hold power declines. Apple has added automatic charging optimization to the Battery Health feature of iOS. From the time your iPhone is updated to iOS 13, this feature is switched on by default.
Even with all Apple's battery health tools the battery on your older iPhone 7 or iPhone 8 could probably still use a little more juice. There's no such thing as too much battery life, and a battery case can provide up to 20 hours of extra browsing, video watching and texting.
Since Optimized Battery Charging already comes enabled when you install iOS 13 or later, here's how to disable it. You can follow the sames steps to enable it if you decide you want to optimize your battery health. This is recommended for all devices, especially older devices.
With the launch of iOS 13, Apple has switched its focus from battery life to battery health. The new software includes a feature called, Optimized Battery Charging. OBC can be found in Settings > Battery > Battery Health, but it comes automatically enabled when iOS 13 is installed. The new battery feature reduces battery aging by learning your "daily charging routine" so your iPhone can wait to finish charging past 80 percent, for when you need it most.