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Why Does Battery Voltage Drop?

Anonymous Thu 17 Mar 15:18:16 2022 No.14311421 View Reply Original Report

Quoted By: >>14311508 >>14311514 >>14311701 >>14311747

Why does battery voltage drop when a load is supplied? I'm trying to think in terms of Ohm's law, and I can't figure it out.
https://youtu.be/LEzkoF-gAn4?t=1345

Anonymous

Anonymous Thu 17 Mar 2022 15:43:05 No.14311474 Report

Quoted By: >>14311483

internal resistance

Anonymous

Anonymous Thu 17 Mar 2022 15:48:34 No.14311483 Report

Quoted By: >>14311495

>>14311474
please explain

Anonymous

Anonymous Thu 17 Mar 2022 15:56:45 No.14311495 Report

Quoted By: >>14311507

>>14311483
Resistance of the electrolyte due to the ions. Most layman definition.

Anonymous

Anonymous Thu 17 Mar 2022 16:03:04 No.14311507 Report

Quoted By: >>14311630 >>14311743

>>14311495
Wrong. The battery having an internal resistance is a MODEL, whereby you assume that the EMF's loss of voltage is Ohmic (untrue). The real answer, OP, is complicated quantum mechanics.

Anonymous

Anonymous Thu 17 Mar 2022 16:03:19 No.14311508 Report

Quoted By:

>>14311421
The first big spike you see in current (blue) is due to the initial spark required and to get the electronic and electrical systems running. Then the electronic system caps the withdrawn voltage and current to preserve battery life.

Anonymous

Anonymous Thu 17 Mar 2022 16:08:28 No.14311514 Report

Quoted By: >>14311519

>>14311421
A battery functions as essentially a capacitor, which means that its voltage is determined primarily by the stored charge and the resistance of the internal capacitor material. When there's a free path between the +/- side of the capacitor, then the voltage will drop because the potential split between the internal part of the capacitor and the rest of the circuit.

Anonymous

Anonymous Thu 17 Mar 2022 16:09:31 No.14311519 Report

Quoted By: >>14311527

>>14311514
That is not how batteries work in the slightest. Batteries are chemical, not capacitive.

Anonymous

Anonymous Thu 17 Mar 2022 16:12:46 No.14311527 Report

Quoted By:

>>14311519
Yes.
It's a set of stored chemical ions split between positive and negative chambers, which cause electron movement along a circuit when a free path is available.
It's a chemical capacitor, with a positive side, a negative side, and a resistant material between the two.

Anonymous

Anonymous Thu 17 Mar 2022 16:13:07 No.14311529 Report

Quoted By: >>14311613 >>14311638

Resistance

Whether its due to current load or due to material flaws. Resistance drops the voltage.

For example, when you're putting the battery to use by powering a device with it, currents are acting like a temporary resistance. The more current you draw, the more resistance there is to draw more current. Alternatively, if the battery material has built up corrosions/dusts/lacks ample amount of contact/etc, then that creates a physical material blockage.

Anonymous

Anonymous Thu 17 Mar 2022 16:46:51 No.14311613 Report

Quoted By:

>>14311529
You obviously didnt see the video op linked.

Anonymous

Anonymous Thu 17 Mar 2022 16:56:02 No.14311630 Report

Quoted By: >>14311710

>>14311507
>The real answer, OP, is complicated quantum mechanics.
Do different types of batteries change voltage at different rates for the same load? Would a lithium-ion battery vary less in voltage than a lead-acid battery given the same load?

Anonymous

Anonymous Thu 17 Mar 2022 16:58:17 No.14311638 Report

Quoted By:

>>14311529
We're talking about the voltage read from terminal to terminal, not the voltage read from the load to one of the terminals.

Anonymous

Anonymous Thu 17 Mar 2022 17:25:07 No.14311701 Report

Quoted By: >>14311706

>>14311421
>why does moving things require more energy

Anonymous

Anonymous Thu 17 Mar 2022 17:28:06 No.14311706 Report

Quoted By: >>14311710 >>14311711

>>14311701
Shouldn't the voltage at the terminals remain constant?

Anonymous

Anonymous Thu 17 Mar 2022 17:30:25 No.14311710 Report

Quoted By:

>>14311706
In an ideal battery yes.
>>14311630
Yes, but anything can be contributing such as impurities in the chemicals, imperfections in the geometry of the battery, etc. It's not as easy as identifying the elements as the sole contributor to the voltage drop.

Anonymous

Anonymous Thu 17 Mar 2022 17:30:28 No.14311711 Report

Quoted By:

>>14311706
Idunno man, I'm not an electrician, but it just sounds like there has to be some discharge of energy for things to move around

Anonymous

Anonymous Thu 17 Mar 2022 17:48:24 No.14311743 Report

Quoted By:

>>14311507
all models are wrong and some are useful. the internal resistance model is very useful if you understand its limitations.

Anonymous

Anonymous Thu 17 Mar 2022 17:50:07 No.14311747 Report

Quoted By:

>>14311421
the battery dies from the first diay it was born, just like us brah

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