Suppose I have a cell/battery , both the terminals are at non-zero potentials.If I connect a piece of wire to say the negative terminal will there be some sort of electron redistribution in the wire. The wire was initially at zero potential , when it's attached to the terminal which is at nonzero potential , shouldn't electrons redistribute themselves to make the wire equipotential ? what will be the potential of the wire if there is such a thing , I guess its the same as that of the terminal be for the wire was connected , because the way I'm seeing things , the wire appears to be just an extension of the terminal.
Unless the metal of the wire is the same as the metal of the battery terminal, there will be redistribution of charge, because of diffusion of charge carriers. The side with the higher concentration of electrons will lose some, the side with the lower concentration will gain some, in the vicinity of the connecting surfaces. This diffusion makes a small internal voltage gradient.
Because this phenomenon is temperature-dependent, it is useful in measurement (thermocouples). As for a battery, its 'negative' or 'positive' terminals aren't absolute-voltage references, those values only come into play through infinitesimal stray capacitance, stray conductance, and other minor effects, unless more connections than just one battery terminal and the wire are made.
A complete circuit can be sketched with stray capacitances, but one usually ignores the static electric effects (until there's enough energy to give you a jolt after shuffling shoes on carpet). Capacitance is a useful concept for a one-terminal device, if high voltages are present.