Although the phrase "seat of EMF" in describing chemical cells has fallen into disuse, by distinguishing the distinct but incorrect conceptions both of Galvani and of Volta, in favor of the correct view of Faraday, "seat of EMF" it becomes possible (among other things) to understand: (1) why internal resistance really is internal; (2) why small AAA cells have the same 1.5-V EMF as much larger D cells; (3) why AAA cells provide a given current for much less time than D cells; and (4) why there is a difference between a slow (and fast) charge and discharge of an automobile battery. The present work is directed to these four issues and others, such as how to estimate the internal resistance of a car battery (about 0.01 [omega] when well charged), of what is generally true for all voltaic cells, and of what is not generally true for all voltaic cells. The author distinguishes between the free charge Q on the electrodes and the much more abundant "releasable" charge Q[subscript R] in the electrolyte.