The Volt:
The standard unit of potential difference or electrical potential, also known as electromotive force (emf), is the volt, represented by V. One volt is equal to one joule per coulomb (1 J/C). The volt is, in real-world terms, a moderately small unit of electrical potential. A normal dry cell of the sort you find in a flashlight (frequently erroneously known as battery), generates around 1.5 V. Most automotive batteries in the United States generate between 12 and 13.5 V.