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I've been trying to understand what voltage in battery is and have come to some sort of understanding, but would like some validation.enter image description here

With this work of art I'll try to explain my thought process, starting with A1 and A2: In batteries the chemical redox reaction creates a potential difference, analogous to height of a mass. Whether we connect more batteries won't matter for the individual battery, it's voltage stays the same.

As every electron in the chain around the circuit moves one step (see red dots), that one step will facilitate both battery reactions giving the hole system double the energy per electron that a system with only one battery would give. E1 moves down one step and both e2 and e3 is increased in energy from the redox reaction in the battery.

So instead of the concept of electrons in anode pushing and a void in cathode pulling electron, I rather view it as the energy given of one redox reaction of one battery is the amount of force the individual electron feels to complete the circuit.

One electron feels the force from the potential difference of two redox reactions because every move it makes in the circuit is one more electron given to both reactions.

After all this I started to think of a circuit like the one in the lower left (two 1 volt batteries, two 1 ohm resistors) and thought since the voltage add in batteries in series this would mean 2 V in both B1 and B2 without resistors. But confusion hit when I add resistors.

How am I to think of the distribution of voltage across the resistors. Each battery having their voltage distributed over two 1 ohm resistor series, meaning: 0.5 V from each battery over both resistors meaning 1 V over both resistors? And what is the volt diagram for a circuit like this?

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  • $\begingroup$ You need to include the internal resistance of each battery in the circuit. $\endgroup$
    – Bob D
    Sep 24, 2021 at 15:33
  • $\begingroup$ ...and/or, the resistance of the wires. Either one (the battery resistance or the wire resistance) could dominate the other depending on the size of the batteries and the gauge of the wires. From a theoretical point of view though, both resistances can be lumped together. $\endgroup$ Sep 24, 2021 at 16:16

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How am I to think of the distribution of Voltage across the resistors. Each battery having their Voltage distributed over a two 1 ohm resistor series, meaning: 0.5 V from each battery over both resistors meaning 1 V over both resistors?

Yes, that is a good way to think of it.

The justification for thinking of it that way is that this is a linear circuit so the principle of superposition applies. If you set one battery to 0 then you have 0.5 V across each resistor. If you set the other battery to 0 then you again have 0.5 V across each resistor. The principle of superposition then allows you to say that the voltage due to both batteries is the sum of the voltages due to each individual battery, which is 1 V across each resistor.

One word of advice: in your earlier description you seem overly focused on electrons. I would try to avoid even thinking about electrons outside of quantum mechanics or chemistry.

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