iPhone has an internal, lithium-ion rechargeable battery. You can charge your battery whenever you want. There’s no need to let it discharge 100% before recharging. Note: Learn more about Apple lithium-ion batteries at www.apple.com/batteries/
Use the USB lighting cable that came with your device. Your Apple lithium-ion battery uses fast charging to quickly reach 80% of its capacity, then switches to slower trickle charging. The amount of time it takes to reach that first 80% will vary depending on your settings. Note: Use the original charger to maintain optimal battery performance over the life of your device.
To charge via a power outlet, connect iPhone to a power outlet using the included Lightning USB to USB cable and power adapter. Note: Your device charges quicker using a power outlet then when connected to a laptop or other power source.
To charge via a computer, connect iPhone to the computer using the included Lightning to USB cable. Note: Make sure your computer is plugged in and powered on when you’re using it to charge your device. If your device is connected to a computer that’s turned off, is in sleep or standby mode, your devices battery may drain.
When your device is charging, you’ll see a small lightning bolt next to the iPhone battery icon showing the device plugged in. Note: Learn what to do if your device doesn’t charge when you plug it in.
When your iPhone is on, you’ll see the battery indicator in the upper-right corner of the screen. This shows how much battery life is left. Note: If you want to see the battery percentage in the status bar, go to Settings > Battery. Then turn on Battery Percentage.
If the Battery icon is yellow, ‘Low Power mode’ is on. When your device reaches 20 percent battery, you're automatically prompted to enable Low Power mode. Note: To manually turn Low Power mode on or off, go to Settings > Battery.
If you see this screen, it means your battery is really low. Plug in your device and let it charge for at least 10 minutes before using it. After that, you can use your device while it continues to charge. Note: If your device has turned off, you might see a black screen for a few minutes even after you plug it in. Let it charge until it turns on, or until it's fully charged.
Power and Battery: Note: All battery claims depend on network configuration and many other factors; actual results will vary. The battery has limited recharge cycles and may eventually need to be replaced by an Apple service provider. Battery life and charge cycles vary by use and settings. To learn more, go to www.apple.com/batteries. Rechargeable batteries have a limited lifespan. Find out how to replace your battery.
To view battery usage information go to Settings > Battery. Note: To learn more about your charging your battery, from a computer, download the user manual at www.att.com/devicehowto. For information about extending your battery performance, see the 'Battery life' tutorial.