Why do electrons flow against their nature in a battery?

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SUMMARY

Electrons flow against their natural tendency in a battery, resulting in increased potential energy, which is defined as electromotive force (EMF). This process occurs in galvanic cells, where chemical energy is converted into electrical energy during charging and discharging cycles. Charging involves a reversible reaction under external current, while discharging occurs as electrons traverse the circuit, losing potential energy across resistances, creating a potential difference (PD). EMF is specific to energy sources like batteries and solar cells, whereas PD is a broader term applicable in various contexts.

PREREQUISITES
  • Understanding of electromotive force (EMF) and potential difference (PD)
  • Familiarity with galvanic cells and chemical reactions
  • Knowledge of electrical circuits and resistance
  • Basic principles of electron flow and ion migration in chemical cells
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  • Research the principles of galvanic action and oxidation reactions in batteries
  • Learn about the differences between EMF and potential difference in electrical circuits
  • Explore the mechanisms of charging and discharging in secondary cells
  • Investigate the role of ions in chemical cells versus free electrons in conductive materials
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Electrical engineers, physics students, battery technology researchers, and anyone interested in understanding the principles of electromotive force and battery operation.

gracy
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Electrons naturally flow from lower to higher potential but inside a battery electrons flow against their nature so that's why their potential energy increases that's what EMF is(energy given per coulomb)right?EMF is always of source i.e battery. And battery such as galvanic cell does so by using chemical energy.right?And this is called charging .And then electron spends all these energy throughout the circuit while crossing resistance and at last returns to battery again with all potential energy used up.This process is called discharging .right?
 
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gracy said:
Electrons naturally flow from lower to higher potential but inside a battery electrons flow against their nature so that's why their potential energy increases that's what EMF is(energy given per coulomb)right?EMF is always of source i.e battery. And battery such as galvanic cell does so by using chemical energy.right?And this is called charging .And then electron spends all these energy throughout the circuit while crossing resistance and at last returns to battery again with all potential energy used up.This process is called discharging .right?
This chemical reaction that gives rise to the EMF is not referred to here as charging. You could call it galvanic action, or an oxidation reaction that liberates electrons.

Charging (also known as recharging) occurs when the reversible reaction in a secondary cell proceeds under the application of an externally-sourced current.

One small but important quibble is that the electrons originating in the cell don't zip around the circuit to quickly return to the positive terminal. They meander along at a surprisingly slow average speed, jostling and pushing ahead of them some of the electrons already present in the conductive wires. A particular electron that leaves the negative terminal may never make it back to the positive terminal; an electron from one of the wires may happily take its place instead.
 
Last edited:
NascentOxygen said:
This chemical reaction that gives rise to the EMF is not referred to here as charging. You could call it galvanic action, or an oxidation reaction that liberates electrons.

Charging (also known as recharging) occurs when the reversible reaction in a secondary cell proceeds under the application of an externally-sourced current.

One small but important quibble is that the electrons originating in the cell don't zip around the circuit to quickly return to the positive terminal. They meander along at a surprisingly slow average speed, jostling and pushing ahead of them some of the electrons already present in the conductive wires. A particular electron that leaves the negative terminal may never make it back to the positive terminal; an electron from one of the wires may happily take its place instead.
ok just don't take it as recharging and discharging but is this difference between EMF and PD(Voltage)?
Electrons naturally flow from lower to higher potential but inside a battery electrons flow against their nature so that's why their potential energy increases that's what EMF is(energy given per coulomb)
.And then electron spends all these energy throughout the circuit while crossing resistance .Whenever they(electrons)cross any resistance their potential energy decreases so this causes potential difference between two points across the resistance.
So source such as battery provides energy in the form of EMF and then this energy is being used while crossing resistance which results in potential difference.
 
gracy said:
ok just don't take it as recharging and discharging but is this difference between EMF and PD(Voltage)?
EMF is a term usually applied to the voltage generated by a battery, alternator, PV solar cell, electric eel, thunderstorm cloud, etc. PD is a general term you can use anywhere.
 
NascentOxygen said:
EMF is a term usually applied to the voltage generated by a battery, alternator, PV solar cell, electric eel, thunderstorm cloud, etc. PD is a general term you can use anywhere.
What about my post 3 is it right?
 
gracy said:
What about my post 3 is it right?
Yes.

While we'll often represent current as flowing through a battery to complete the circuit's electrical loop, remember in a chemical cell it is ions that are migrating through the solutions, not free electrons.
 
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NascentOxygen said:
Yes.

While we'll often represent current as flowing through a battery to complete the circuit's electrical loop, remember in a chemical cell it is ions that are migrating through the solutions, not free electrons.
Thanks a lot.You cleared all my doubt.
 

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