Question

This battery has a difference in potential energy between the positive and negative terminal. Which units express this difference in energy?

Answer 1

The unit of energy is always Joules. For a battery, the difference between the terminals is a difference in POTENTIAL, measured in joules per coulomb or, more commonly, in 'volts'. 1 volt = 1 Joule per coulomb.

Answer 2

The unit for energy is ALWAYS joules (J)