Hi all, I'm trying to nail very precisely the effects of a battery in terms of charge separation. In particular: when and what points are excess charges seen in a typical circuit powered by a battery. A. Prior to wires being attached to the battery, you just have the battery itself. My understanding is that in modern batteries, there is NO EXCESS CHARGE whatsoever at either pole (at this point)...which allows batteries to live for a long time on a shelf without "leaking." Is this true? Are both poles neutral prior to a wire being attached? B. Now, attach the wires, but do not create a circuit. Do the free electrons in the wires allow the chemical half-reactions at each cell to proceed? Is there now any net excess charge in either wire? C. Once you complete the circuit, chemical reactions proceed and there is small excess charge at each end of the battery (and, indeed, in the wires coming out from each one). That is the case that is clear...but my question is whether there is any charge separation at all in the batteries prior to the circuit being formed.