Examining DC Signals & Batteries: What's the Difference?

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Discussion Overview

The discussion explores the differences between DC signals and batteries, particularly focusing on the nature of current flow in batteries and the underlying chemical processes. Participants examine the concept of switching frequency in relation to battery operation and ion transport rates, as well as the implications of these phenomena on the observed output of batteries.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants suggest that a DC signal from a battery may have a high switching frequency due to rapid chemical reactions occurring within the battery.
  • Others question the concept of "switching frequency" in the context of a battery, seeking clarification on what is meant by this term.
  • One participant proposes that the smallest charge is an electron, implying there is a rate of generation or conversion related to electron flow.
  • Another participant introduces the idea of ion transport rates within the battery, suggesting this rate is linked to the flow of electrons in the circuit.
  • Some participants express confusion over the explanation of ion transport and request a clearer framing of the discussion.
  • A later reply notes that while ions do not flow through the circuit, they move through the electrolyte, and emphasizes that there is no switching involved in this process.
  • One participant mentions that the transitions at the atomic level within a battery happen at very fast rates, which may not be detectable with current instruments, leading to the practical consideration of battery output as continuous.
  • Another participant introduces the concept of "switching" at a fundamental level, suggesting it could be modeled using quantum mechanics, although this remains a speculative idea.
  • Some participants express uncertainty about the relevance of weak interactions to the discussion, with one asserting that it does not apply to the observed phenomena.

Areas of Agreement / Disagreement

Participants express a range of views on the nature of current flow in batteries and the concept of switching frequency, with no consensus reached on these points. There is ongoing debate about the relevance of ion transport rates and the applicability of weak interactions.

Contextual Notes

Limitations include unclear definitions of terms like "switching frequency" and "ion transport," as well as unresolved questions regarding the relationship between observed phenomena and theoretical models.

y33t
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If you study a DC signal under an appropriate scope, you can see the switching transitions ; a pwm signal.

But if you examine a battery, no matter how high temporal resolution you reach, you see a dc signal.

What might be the explanation for this? electrons are being generated by a chemical process in battery and these reactions are very fast so the switching frequency of battery can be very high. What should be the approach to this problem?
 
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y33t said:
... so the switching frequency of battery ...

Huh? WHAT "switching frequency" of a battery? I don't understand what you mean.
 
Smallest possible charge is 1 electron thus there should be some sort of rate to generation/conversion.
 
rate to generation/conversion of what ?
 
davenn said:
rate to generation/conversion of what ?

Ion transport rate.
 
y33t said:
Ion transport rate.

Let join the chorus here: what ion transport?!

By now, you should have a sense that you are not explaining yourself very well here. The first 3 responses are us trying to figure out what exactly it is that you are talking about.

So how about starting all over again and put some effort into framing this as best as you can.

Zz.
 
ZapperZ said:
Let join the chorus here: what ion transport?!

By now, you should have a sense that you are not explaining yourself very well here. The first 3 responses are us trying to figure out what exactly it is that you are talking about.

So how about starting all over again and put some effort into framing this as best as you can.

Zz.

I am sorry, trying again.

When you connect a resistive load across terminals of a battery, a direct current will start flowing ; meaning specific amount of electrons propagating per crosssection but how about the repetition rate of this process? Inside the battery ions are being transported and there is a rate of this phenomena.
 
y33t said:
I am sorry, trying again.

When you connect a resistive load across terminals of a battery, a direct current will start flowing ; meaning specific amount of electrons propagating per crosssection but how about the repetition rate of this process? Inside the battery ions are being transported and there is a rate of this phenomena.

This ion transfer rate is equal to the rate of electrons flowing through the circuit between the terminals of the battery. If it wasn't a net charge would build up and prevent any further current flow from one terminal to the other.

Note that there is no switching involved here. The ions do not flow through the circuit, but through the electrolyte.

From wiki: http://en.wikipedia.org/wiki/Electrochemical_cell

As electrons flow from one half-cell to the other, a difference in charge is established. If no salt bridge was used, this charge difference would prevent further flow of electrons. A salt bridge allows the flow of ions to maintain a balance in charge between the oxidation and reduction vessels while keeping the contents of each separate.
 
Drakkith said:
This ion transfer rate is equal to the rate of electrons flowing through the circuit between the terminals of the battery. If it wasn't a net charge would build up and prevent any further current flow from one terminal to the other.

Note that there is no switching involved here. The ions do not flow through the circuit, but through the electrolyte.

From wiki: http://en.wikipedia.org/wiki/Electrochemical_cell

Thank you for the information.
 
  • #10
y33t said:
What might be the explanation for this? electrons are being generated by a chemical process in battery and these reactions are very fast so the switching frequency of battery can be very high. What should be the approach to this problem?
The transitions within a battery at the atomic level happen at a very fast rate and they overlap. There aren't any real world instruments sensitive and fast enough to see the very slight and very fast flucuations in the output of a battery. From a practical standpoint, the output of a battery can be considered to be continous.
 
  • #11
That's what I was talking about but didn't wanted to push more after I observed that I could'nt express myself to majority efficiently.

The main phenomena responsible is;
http://wikipedia.org/wiki/Proton_coupled_electron_transfer

And it's being driven sequentally, but they overlap as you say and that's the main problem. If you study the problem further you are going to realize that there exists some sort of 'switching' indeed, and it should be around on the orders of ~E+24 due to fundamental properties of Weak Interaction.

Maybe this problem can be modeled using QM more precisely, approach should be right.

As of today, mankind is on the orders of E-18 which is far from probing E-24.

Thank you.
 
  • #12
y33t said:
And it's being driven sequentally, but they overlap as you say and that's the main problem. If you study the problem further you are going to realize that there exists some sort of 'switching' indeed, and it should be around on the orders of ~E+24 due to fundamental properties of Weak Interaction.

1. What is this switching problem?

2. I don't see how the weak interaction applies in this situation.
 
  • #13
1.No problem, solved.
2.I can't say that I understand fully either. But I can say that it's much faster than emf because can't see the propagation delay between electrolytes. Distance between them is 6cm so it would take 200ps minimum, I have a scale of 40ps on my scope but still get a phase difference of 0.
 
  • #14
y33t said:
1.No problem, solved.
2.I can't say that I understand fully either. But I can say that it's much faster than emf because can't see the propagation delay between electrolytes. Distance between them is 6cm so it would take 200ps minimum, I have a scale of 40ps on my scope but still get a phase difference of 0.

I can confidently say that the weak interaction has nothing to do with this.
 
  • #15
And on that note, this thread is done.

Zz.
 

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