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Ever since I started reading about electrostatics and current electricity I have gotten ever so confused by various things. After watching video lectures by several different people and reading several different books on the topics I think I have somewhat got an understanding. My question is whether my understanding of how a battery works is correct or am I still misinterpreting something. My understanding is as follows:

A battery provides a force onto an electron at the positive terminal and does work on it to move it against the electric field to the negative terminal. This work done on the electron is stored as potential energy of the battery.
Now the electron is not held in place by any force so the potential energy is converted to kinetic energy (since it is repelled by the negative terminal of the battery).
This kinetic energy is depleted as the electron moves through the circuit due to collisions with other particles and electrons. Areas of higher resistance cause more collisions and hence more kinetic energy is transformed into heat and light energy. Now unless the resistance is infinite the elections will always have some amount of kinetic energy that will allow them to reach back to the positive terminal of the battery. Now the process repeats.

I am pretty sure I have still missed something about how exactly the electron "passes" through the battery as I am not sure whether it actually physically passes through the battery or for some reason it reaches the positive terminal and a different electron is emitted out on the other side.

I would be really thankful if someone could take a few minutes to read the essay I have written above and let me know if I am right or wrong.

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    $\begingroup$ This comes up fairly often over at the chemistry stack exchange. You can benefit greatly by getting this and working through it: K. Schmidt-Rohr, "How Batteries Store and Release Energy: Explaining Basic Electrochemistry", J. Chem. Ed., 95 (10) (2018) 1801-1810. The Zn and Cu Daniell cell is addressed in great detail. TL; DR Cohesive energy differences are the major factor in explaining the behavior of this famous galvanic cell. Look up the famous Daniell cell. $\endgroup$
    – Ed V
    Commented Nov 26, 2021 at 13:38
  • $\begingroup$ Alright I will go through it as soon as my exams finish. Thanks a lot! $\endgroup$
    – Anili
    Commented Nov 26, 2021 at 13:50

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A battery provides a force onto an electron at the +ve terminal and does work on it to move it against the electric field to the -ve terminal. This work done on the electron is stored as potential energy of the battery.

This is not too bad, but you are neglecting the electrolyte. In a battery there are two electrodes. At one, an electron is consumed in the electrode and at the other an electron is produced in the electrode. Conversely, at one an ion is produced in the electrolyte and at the other an ion is consumed in the electrolyte. In the electrolyte the ions move to produce current from one electrode to the other. (Note that this usually involves positive charge carriers moving in the direction of the current as well as negative charge carriers moving in the opposite direction)

Now the electron is not held in place by any force so the potential energy is converted to kinetic energy (since it is repelled by the -ve terminal of the battery).

The KE of the electron is not at any time relevant in an ordinary circuit. Electrons are very light and their drift velocity is very slow. So $1/2 \ mv^2$ is insignificant for them.

This kinetic energy is depleted as the electron moves through the circuit due to collisions with other particles and electrons. Areas of higher resistance cause more collisions and hence more kinetic energy is transformed into heat and light energy.

The electrons do not carry energy in a standard circuit. The energy is carried by the fields. This is governed by Poynting’s theorem. The role of the electrons is not to carry energy, but to create the fields that in turn actually carry the energy.

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  • $\begingroup$ Well since I am in high school I haven't actually read much about Poynting's theorem however I did watch the recent Veritasium video on the topic. Is there any resource you could point me too that could explain this topic in an easy to understand/basic way? I would really appreciate it. Also thanks a lot for the answer, it makes things much clearer. $\endgroup$
    – Anili
    Commented Nov 26, 2021 at 13:53
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    $\begingroup$ @Anili unfortunately, I did not encounter the Poynting vector until my second semester at university. And I didn’t understand the connection with circuits until well after my PhD. I don’t have any high-school level references. Sorry $\endgroup$
    – Dale
    Commented Nov 27, 2021 at 0:38
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    $\begingroup$ @Anili your interpretation is wrong. If the electrons carried the energy then it would take hours between flipping on a switch and the bulb lighting in an ordinary residential circuit. $\endgroup$
    – Dale
    Commented Nov 27, 2021 at 5:11
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    $\begingroup$ What I intended to say was that I would consider my interpretation for school since my teachers (and the textbooks) say that the electrons carry the energy and I would not be able to use the concept of Poynting's vector in my day to day interactions with my teachers nor would I be able to use it in my examinations. However I will keep in mind that the electrons do NOT carry the energy and the fields carry it. $\endgroup$
    – Anili
    Commented Nov 27, 2021 at 10:21
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    $\begingroup$ @Anili yes, that is right. Even if I had a good reference for you it wouldn’t change the practical issues you mentioned $\endgroup$
    – Dale
    Commented Nov 27, 2021 at 12:44

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