Why do electrons flow against their nature in a battery?

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In summary, electrons naturally flow from lower to higher potential, but inside a battery they flow against their nature, resulting in an increase in potential energy. This is known as EMF, or energy given per coulomb, which is always the source of a battery. Charging occurs when a reversible reaction in a secondary cell proceeds under the application of an externally-sourced current, while discharging is when the electron spends all its energy throughout the circuit while crossing resistance and returns to the battery with all potential energy used up. There is a difference between EMF and PD (voltage), where EMF is specific to certain sources and PD is a general term. It is important to remember that in a chemical cell, it is ions that are migrating
  • #1
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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  • #2
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.
 
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  • #3
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.
 
  • #4
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.
 
  • #5
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?
 
  • #6
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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  • #7
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.
 

What is the difference between recharging and discharging?

Recharging is the process of restoring energy to a battery or electrical device, while discharging is the process of releasing stored energy from a battery or electrical device.

How do batteries recharge?

Batteries recharge by passing an electrical current through them in the opposite direction of discharging. This causes the electrochemical reaction within the battery to reverse, restoring the battery's energy.

What factors affect the speed of recharging and discharging?

The speed of recharging and discharging can be affected by the type and size of the battery, the amount of voltage and current used, and the temperature of the environment. Higher voltages and currents and higher temperatures can speed up the process, but can also cause damage to the battery.

Is it necessary to completely discharge a battery before recharging it?

No, it is not necessary to completely discharge a battery before recharging it. In fact, it is recommended to avoid fully discharging a battery as it can decrease its overall lifespan. It is best to recharge a battery before it reaches a critically low level.

Can a battery be overcharged or over-discharged?

Yes, a battery can be overcharged or over-discharged. Overcharging can cause damage to the battery and even result in fire or explosion. Over-discharging can also damage the battery and decrease its lifespan. It is important to use the correct charging methods and monitor the battery's level to avoid overcharging or over-discharging.

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