1. Avoid extremes of heat and cold.
If your phone gets very hot or cold it can strain the battery and shorten its lifespan. Leaving it in your car would probably be the worst choice if it’s hot and sunny outside.
2. Avoid fast charging.
Charging your phone quickly stresses the battery. In fact, the slower you charge your battery the better. Charging your phone from your computer as well as certain smart plugs can limit the current going into your phone, slowing its charge rate.
3. Reduce the screen timeout
If you leave your screen on without using it, it will automatically turn off after a period of time, usually one or two minutes. You can save energy by reducing the Screen Timeout. The screen timeout can be managed in the phone settings.
4. Choose a dark theme.
Choosing a dark theme for your phone, can help to save energy. The contrast between black and colour is very sharp and beautiful that displaying black on the screen uses no energy, and darker colours use less energy than bright colours like white. Some people find a darker theme is easier on the eyes in terms of preventing eye strain, and less light overall may mean less blue light, which can affect sleep patterns.
5. Turn down the screen brightness
A smartphone’s screen is the component that typically uses the most battery. Turning down the screen brightness will save energy. Using Auto Brightness probably saves battery for most people by automatically reducing screen brightness when there’s less light, although it does involve more work for the light sensor.
credit to : https://lauren-c-stephen.medium.com/13-tips-to-extend-the-lifespan-of-your-phone-battery-16c2af5ca59f