What is voltage in a circuit? We just started learning about electricity in my school. From what I understand; potential is potential energy per Coulomb and voltage means difference in potential. So, if you have a battery with 4 voltage and a wire connecting the poles of the battery, does that mean electrons at the negative pole will have a potential energy of 4∗q, where q is the charge of the electron? And when the electrons have reached the positive pole, all the potential energy will have been transformed? I have a feeling I'm not understanding this concept.