Is It Bad to Leave Your iPhone/MacBook Charging After It's Already Hit Full Battery?
Nope. The internal charging system stops charging the battery when full, and you operate off the power supply or charger in the meantime as most people mistakenly refer to them.
Understanding Battery Charging
While it is generally safe to leave your smartphone plugged in after it has reached full charge, making small adjustments to your charging habits can help extend the overall lifespan of your battery. Regularly monitoring temperature and using built-in software features can also contribute to better battery health.
Official Apple Advice
Apple advises that you can charge your iPhone whenever you like. The battery cannot be overcharged, and it will not suffer any harm from regular charging, including overnight charging. Charging will stop automatically when the battery is fully charged and will start again if and when required due to ongoing battery usage.
Common Misconceptions
Many people mistakenly believe that leaving their devices plugged in can damage the battery. However, once the battery hits 100%, the device consumes the energy required to operate from the power adapter directly and will not drain the battery further. Thus, leaving your iPhone or MacBook plugged in when it’s fully charged is not a problem.
Note: The fear of ferrets building up in your basement is a humorous exaggeration and serves only to highlight the safety of leaving devices plugged in.
iPhone Specifics
When it comes to iPhones, if you leave them plugged in while fully charged, the device will simply operate off the power supply for as long as it remains plugged in. However, if you leave your iPad or other Apple devices plugged in, they will also operate off the power supply to avoid draining the battery.
MacBook Specifics
For MacBooks, if you are using your Macbook plugged in, the charging adapter will stop charging your MacBook as soon as your MacBook battery is full and will act as an AC to DC converter. Therefore, no damage will be done to the battery. However, if your MacBook is in the switched-off state, the charging adapter may act as an iPhone charger and continue to charge your MacBook until you remove it from the wall socket. Therefore, it is recommended to remove the charging adapter as soon as your MacBook is fully charged if it is in a switched-off state.
Conclusion
The short answer is: No. It's not bad.
Tips for Battery Longevity
Avoid Hot Ambient Conditions
Apple recommends that both iPhones and MacBooks work best at 0° to 35° C (32° to 95° F) ambient temperatures. To extend your device’s battery life, avoid charging in extremely hot ambient conditions, like leaving devices exposed to direct sunlight.
Keep Software Updated
Make sure you have the latest software installed on your device. Software updates often include optimizations that reduce battery usage. Check for and enable software optimizations that can help extend battery life.
Monitor Background Processes
Check which apps are using the battery in the background. For example, if an app like Uber is running in the background, you can turn off its background processes since you would be using it only when you need it. Find the best settings for the apps you use and apply them.
Disable Background Location Services
Most apps don’t need background location services, so you can disable them to save battery. This is particularly useful for apps that consume significant battery life.
Manage Unneeded Devices
Disconnect any peripherals and quit any applications that are not in use. Eject an SD card if you’re not currently accessing it.
Check Battery Health Monitor
Always check your battery health monitor and adjust the settings accordingly. Most modern devices, including iPhones and MacBooks, have built-in battery health monitoring tools that can help you understand and manage your battery more effectively.
By following these tips, you can help ensure your iPhone or MacBook maintains its battery health and lasts longer.