Good to know
Swollen battery? Stop now. A puffy battery can push the screen up or split the back. Unplug it. Keep it out of your pocket and away from heat. Don't press on it. Bring it in soon.
A phone battery is built for a few hundred full charges. For most people that is two or three years. Phone otherwise fine? A new battery can add another year or two.
Charges slowly or only at an angle? That may be the charging port, not the battery. We test both for free.