I've been researching electrochemical cells. In chemistry-focused sources, you usually see the potential difference between the electrodes referred to as cell potential, but in engineering/industrial sources(where you talk about "batteries") you usually see plain "voltage." Are the two always the same, or are there some situations where they're different(excluding multiple cells)? I want to know whether you can use the cell potential formula $$E^o_{cell} = E^o_{cathode} - E^o_{anode}$$ to calculate an accurate standard conditions voltage for a battery. If not, what gets in the way?
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$\begingroup$ I did not alter my answer in response to your edit as the answer basically remains the same. The formula for the cell potential is correct as you have written it and can be used to calculate standard cell potentials so long as you know how to use it. $\endgroup$– airhuffCommented Jul 1, 2017 at 23:50
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2 Answers
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It is not uncommon for two identical phenomena to be described by different terminology in different contexts or scientific disciplines. In this case, voltage and electric potential difference refer to the same thing. According to this Wikipedia article:
Voltage, electric potential difference, electric pressure or electric tension (formally denoted ∆V or ∆U, but more often simply as V or U, for instance in the context of Ohm's or Kirchhoff's circuit laws) is the difference in electric potential energy between two points per unit electric charge. The voltage between two points is equal to the work done per unit of charge against a static electric field to move the test charge between two points. This is measured in units of volts (a joule per coulomb).
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Electrochemical potential is referenced (mostly arbitrarily) towards the standard hydrogen electrode, while "electrical potential" has "ground" as reference (which usually means "zero excess charge"). "Voltage" is the difference in potential, measured in Volts, for both.
The standard hydrogen electrode has 4.44 V relative to an ideal ground (absolute potential, at 25°C), but thats's hard to reproduce, so for all practical purposes, it ($E^0$, standard electrode potential) is defined (by IUPAC) to be zero at all temperatures. It's all relative.
