What is the internal resistance of a battery?

In summary, the origin of internal resistance in a battery is due to the flow of electrons from the negative to positive terminal, which can release heat and combine with electrolytes or move through chemicals inside the battery. This internal resistance can be measured by looking at the voltage as a function of current. The battery itself is considered a load and the flow of electrons can contribute to the chemical changes that occur inside a dry-cell battery, but they are distinct events.
  • #1
Sakhawat Hossain
2
0
Does a battery really have any internal resistance? If it has then what's the origin of the resistance.
We know that the electrons flow from negative to positive terminal of a battery. Do the electrons just end up releasing energy(such as heat) at the terminal/ or combines with the atoms of the electrolytes available there/ or they move through the chemicals inside the battery between two opposite poles?
 
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  • #2
Sakhawat Hossain said:
Does a battery really have any internal resistance? If it has then what's the origin of the resistance.
We know that the electrons flow from negative to positive terminal of a battery. Do the electrons just end up releasing energy(such as heat) at the terminal/ or combines with the atoms of the electrolytes available there/ or they move through the chemicals inside the battery between two opposite poles?
The voltage across the terminals decreases with increased current flow. The battery itself will get hot as it delivers current. This means there is an internal resistance.

By measuring voltage as a function of current, you can work out the resistance of the battery.[itex]R = (V_0 - V_I)/I[/itex] where V0 is the voltage with 0 current and VI is the terminal voltage when delivering current I to a load.

AM
 
  • #3
Then it means that the battery itself is a load and electrons flow through it.
Let's assume that, the battery used is a dry-cell battery. Now my question is:-
Does this electron-flow contribute to the chemical change that occurs inside a dry-cell battery? I mean, whether some of the electrons are drawn from the flow and account for the chemical change inside the cell. Or whether electron flow and chemical change inside the battery are distinct event (which may effect each other, but are not same).
 

1. What is internal resistance of a battery?

The internal resistance of a battery is the resistance within the battery itself that impedes the flow of electric current. It is caused by the resistance of the materials used in the battery and the movement of ions within the battery.

2. How is internal resistance measured?

Internal resistance is typically measured by using a multimeter to measure the voltage drop across the battery when a known current is applied. The internal resistance can then be calculated using Ohm's law.

3. Why is internal resistance important in batteries?

Internal resistance is important because it affects the overall performance and efficiency of a battery. A higher internal resistance means a battery will have a lower voltage and a shorter lifespan. It can also affect the battery's ability to deliver high currents, which is important for certain applications.

4. How does temperature affect the internal resistance of a battery?

Temperature can significantly impact the internal resistance of a battery. Generally, as temperature increases, the internal resistance decreases, meaning the battery can deliver more current. However, extreme temperatures can also damage the battery and decrease its overall lifespan.

5. What factors can affect the internal resistance of a battery?

Internal resistance can be affected by various factors, including the type of materials used in the battery, the age and condition of the battery, and the temperature. Additionally, the internal resistance may vary depending on the state of charge and the load applied to the battery.

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