Hey Guys, there is one question which is bugging me for the last couple of weeks. I am an embedded software engineer and when it comes to very deep understanding what is going it in the electrical circuits I struggle a lot. Recently I have decided to go through the course of physics again especially electrostatics and electrodynamics and being an engineer started asking questions to myself which never thought about when I was a student. One of the questions which I bumped into and can't find an answer is this one: Suppose I have two batteries connected in series. Why the voltages are added together. I understand roughly physics and electro-chemistry of how the battery works alone. But I am getting lost when two batteries are connected series. How do electrons get more potential energy?