Is the positive terminal of a battery positively charged

In summary, the conversation discusses the concept of electricity and specifically, the movement of charge in a battery. The positive and negative terminals of a battery have a difference of charge distribution, causing an electric field. This charge difference is maintained by the battery consuming chemical energy. However, the movement of electricity is actually the flow of electrons from the negative to the positive terminal. The concept of "hole flow" is also mentioned, where the convention is to suggest the flow of electricity is from positive to negative. There is no electric field inside a battery, but it is present between the terminals. The process of electrons moving in a battery is caused by a chemical reaction, and there is a balance of charge on both electrodes.
  • #1
Moogie
168
1
Hi

If you are kind enough to answer this please bear in mind that I know next to no physics and I'm quite intimidated by the subject so please don't give me an intractable answer that I won't understand. Please feel free to answer as if you are talking to a nice but dim high school student.

The question is in the title. I'm from a biological sciences background trying to learn about electricity. I've just learned a little about electric fields and electric potential and now I'm moving on to current electricity, starting with batteries.

I've just read this:

"Within the electrochemical cells of the battery, there is an electric field established between the two terminals, directed from the positive terminal towards the negative terminal. As such, the movement of a positive test charge through the cells from the negative terminal to the positive terminal would require work, thus increasing the potential energy of every Coulomb of charge that moves along this path. This corresponds to a movement of positive charge against the electric field. It is for this reason that the positive terminal is described as the high potential"

I know this might be an obvious question but does this mean the positive terminal is actually positively charged and the negative terminal is negatively charged? (I have a vague recollection from redox reactions or something that sometimes its not what you would think it is but its so vague I can't remember)

I have searched the forum for an answer to this question but I didn't understand it as it talked about capacitors and I don't know what they are

Many thanks in advance
 
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  • #2
Yes, there is a difference of charge distribution between the two poles, which causes the electric field. When you join the two poles with a conductor, the charges will "feel" this electric field and start moving in the conductor from the positive pole to the negative, thereby reducing the charge difference between the poles. The battery then consumes chemical energy to restore the charge difference, therefore maintaining the initial charge distribution, until the chemical energy finishes.
 
  • #3
That confuses me because I thought electricity was the movement of electrons and I thought a battery was something like this:

Move electrons from A to B. This takes energy. This makes A positively charged and B negatively charged. The electrons at A have higher electric potential as they ahve been separated from 'their proton'. Electrons then move around the circuit from B to A to get back to the point of lowest electric potential.

This comceptualistation is obviously flawed then?
 
  • #4
Yes, actually it's the negative charges that move. But that doesn't matter, as a negative current going one way is the same as a positive current going the opposite way.
 
  • #5
That sounds intuitive and I'm sure it makes sense but I can't quite see it. I think of charge as being an imbalance in the number of electrons and I can only visualise excess electrons moving. I can't get a picture for what positive current is. Can you help me with a model or analogy?
 
  • #6
A battery does have a negative charge (surplus of electrons) on the negative terminal just as you'd expect, and the positive pole of a battery is positively charged (needs electrons to be in equilibrium).

Convention has it that the flow of electricity is from positive to negative but that's not what actually happens. The flow of electrons is from the negative to the positive terminal. This convention of suggesting the 'flow' of electricity is from positive to negative is called "hole flow". There's an interesting http://everything2.com/title/hole+flow" that you might enjoy. Not sure if it's historically accurate but it seems pretty authoritative and I can vouch for the article's treatment of hole flow.
 
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  • #7
Is there actually an electric field inside a battery?

Does a battery use energy to pump electrons to the negative terminal?
 
  • #8
Actually I will rewrite that question. Is there an electric field inside the battery? Is there an electric field outside the battery?

I thought electrons were pumped against an electric field inside the battery and this did 2 things:
1) it gave the electrons higher electrical potential
2) created a positive and negative terminal

but this means there is an electric field inside the battery and also between the terminals

Have i got it wrong? Is it that electrons are moved inside the battery by a chemical reaction. This creates an electric field due to the charge separation
 
  • #9
Q_Goest said:
A battery does have a negative charge (surplus of electrons) on the negative terminal just as you'd expect, and the positive pole of a battery is positively charged (needs electrons to be in equilibrium).

I might be entirely wrong, but from what I understood of my electrochemistry class is that the charge is actually balanced on both electrodes, but because of the reduction potential, one of the the electrodes 'takes' electrons from the other electrode, and becomes reduced, while the other electrode oxidizes.
Moogie said:
Is there actually an electric field inside a battery?

Does a battery use energy to pump electrons to the negative terminal?

I'm pretty sure there is no electric field inside a battery, even tho electric fields are used in capacitors.

Electrons go from negative terminal to the positive.


Hope that helps on something, don't take my word to be true, I just wrote what I inferred from classes.
 

1. What does it mean for the positive terminal of a battery to be positively charged?

The positive terminal of a battery is positively charged because it contains an excess of positively charged particles, known as protons. This creates an electrical potential difference between the positive and negative terminals of the battery, which allows for the flow of electrons and the generation of electrical energy.

2. Why is the positive terminal of a battery labeled as positive if it contains protons?

The labeling of the positive terminal as positive is a convention that was established before the discovery of subatomic particles. At the time, it was believed that electrical current flowed from positive to negative. While we now know that current actually flows from negative to positive, the convention has remained the same for consistency and simplicity.

3. Can the positive terminal of a battery be negatively charged?

No, the positive terminal of a battery cannot be negatively charged. As mentioned earlier, the positive terminal contains an excess of positively charged particles, which creates a positive charge. The negative terminal, on the other hand, has an excess of negatively charged particles, making it negatively charged.

4. What happens if you switch the positive and negative terminals of a battery?

If you switch the positive and negative terminals of a battery, the flow of electrons will be reversed, resulting in the battery becoming discharged. This is because the positive terminal is connected to the negative end of the circuit, and vice versa. It is important to always connect the terminals correctly to ensure proper functioning of the battery.

5. How is the positive terminal of a battery different from the negative terminal?

The positive terminal of a battery is different from the negative terminal in terms of its charge and chemical composition. As mentioned earlier, the positive terminal contains an excess of positively charged particles, while the negative terminal has an excess of negatively charged particles. Additionally, the positive terminal is typically made of a different material, such as nickel or manganese, compared to the negative terminal, which is usually made of zinc or lithium.

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