The battery is the main power source of the phone. Without it your Galaxy S5 will be just another expensive paperweight. It is located underneath the back cover and is removable, needless to say, it is also replaceable. The company touted of the phone's better power-saving mode and that might be one of the reasons why it only gave the new flagship 2,800mAh battery, a slight upgrade from S4's 2,600mAh batty.
For power-related issues, the battery should be the first one to be checked and to guide you in your troubleshooting, ask yourself the following questions:
- Is the battery charged?
- Is it properly mounted?
- Are there any liquid elements present?
- Does the battery have physical deformities like lumps or signs of swelling?
To make it simpler, here are the things you should do if your phone refuses to power on:
- Plug the charger in and let the device charge for, at least, 10 minutes and while waiting for the time to elapse, look for signs that the phone is properly charging. You should see the LED glowing red and the usual "charging" symbol on the screen.
- If the phone doesn't show the usual charging signs, remove the back cover, pull the battery out and try to mount it properly, and then attempt to charge again. For a totally depleted battery, it would take several minutes before the indicators light up, so try to wait that long.
- After several minutes have elapsed and the charging signs don't show or the phone won't power on, pull the battery out and check the liquid damage indicator (LDI), the little sticker in the battery compartment. If the little sticker is white, then the phone doesn't have water damage, however, if it turned pink, red or purple, the liquid found its way inside.
- It is also wise to check the battery for swelling, lumps or leaks. A battery that manifests any of those needs to be replaced as soon as possible. Defective or damaged batteries have a tendency to over-charge and explode.
WARNING: Do not attempt to open or repair the battery. Just don’t!
If you don't want to buy a spare battery, it would be wise to borrow from someone who has the same phone as you.