Batteries in series: how does this work?

Devrij

Devrij

Devrij

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I was just pondering this and couldn't make sense of it in my head, so I'm appealing to GD to show me where I'm being retarded.

If you have two batteries in series, the positive end of the 2nd battery is connected to the negative end of the other battery, which should act like a short circuit discharging that battery into the other one and basically halving the potential difference across the whole circuit as though there was only one battery.

But that isn't the case so where am I going wrong here?
 
Placing positive again negative isn't a short circuit - it's not a circuit!

Each cell has a potential difference between the terminals. Put two in series and the potential differences add up between the ends.
 
Devrij said:
I was just pondering this and couldn't make sense of it in my head, so I'm appealing to GD to show me where I'm being retarded.

If you have two batteries in series, the positive end of the 2nd battery is connected to the negative end of the other battery, which should act like a short circuit discharging that battery into the other one
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No, that's an open circuit because the other two ends aren't connected.

Devrij said:
and basically halving the potential difference across the whole circuit as though there was only one battery.
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What?
 
Devrij said:
I was just pondering this and couldn't make sense of it in my head, so I'm appealing to GD to show me where I'm being retarded.

If you have two batteries in series, the positive end of the 2nd battery is connected to the negative end of the other battery, which should act like a short circuit discharging that battery into the other one and basically halving the potential difference across the whole circuit as though there was only one battery.

But that isn't the case so where am I going wrong here?
Click to expand...

I think you need to go into the flight panel section, select repair module and that should hopefully fix it.
 
joeyjojo said:
Placing positive again negative isn't a short circuit - it's not a circuit!

Each cell has a potential difference between the terminals. Put two in series and the potential differences add up between the ends.
Click to expand...

Yeah, but why doesn't the positive side flow into the negative side of the other battery? I know this isn't how it works, but why doesn't the side full of electrons just flow into the other battery's positively charged end, neutralising it and leaving that battery with one positive end and one neutral and and another with a negatively charged end and a neutral end?
 
Devrij said:
Yeah, but why doesn't the positive side flow into the negative side of the other battery? I know this isn't how it works, but why doesn't the side full of electrons just flow into the other battery's positively charged end, neutralising it and leaving that battery with one positive end and one neutral and and another with a negatively charged end and a neutral end?
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As someone who has worked in electronics for 6 years, I have no idea what you are trying to ask.

Unless you close the circuit then the electrons will not 'flow' because there is an infinite resistance between the terminals
 
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most batteries are formed of cells, lead acids for example in a standard car battery they are 6 2v cells connected in series, as this is done in just one 'block' of the battery most folk don't really take note.

the exact reasoning behind how it works on a physical scale is something i can't really explain so well, but i'm sure there are folk on here that can. i like to imagine it like compressed air or water flowing through a pipe, connecting 2 pumps in series doesn't make a short circuit unless the overall 'out' feed [the +ve, or negative depending on what way you judge current flow convention] to the out feed, then you'd be pumping water round a loop with next to no load and you'd blow up the pumps.
 
mushtafa said:
People get so scared of doing this, thinking they'll get an electric shock lol :D
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Yep. I once worked with a guy who thought that sticking two metal pins in a socket would shock him too, so we tried it and he learned something that day.

Perfectly safe, try it!
 
adolf hamster said:
most batteries are formed of cells, lead acids for example in a standard car battery they are 6 2v cells connected in series, as this is done in just one 'block' of the battery most folk don't really take note.

the exact reasoning behind how it works on a physical scale is something i can't really explain so well, but i'm sure there are folk on here that can. i like to imagine it like compressed air or water flowing through a pipe, connecting 2 pumps in series doesn't make a short circuit unless the overall 'out' feed [the +ve, or negative depending on what way you judge current flow convention] to the out feed, then you'd be pumping water round a loop with next to no load and you'd blow up the pumps.
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Interestingly, in the early days of electricity. "Voltage" was indeed refered to as "Pressure"

It is actually a pretty good analogy. (Which you clearly understand quite well)

Put multiple "2 Volt" pumps in series and each will feed the others to produce an overall higher pressure (Voltage) 6 two volt "Pumps" will produce 12 Volts.

By contrast, put them in parallel and you don't get any greater pressure as such but a corresponding multiple of volume flow. Ie, it will still be only 2 volts, but you have the capability to provide a far greater current flow (volume)

Connect the output to the input with no load (or pressure drop) in between and you will end up with massive flow (limited only by the internal resistance of the battery/pump) this will generate a large amount of heat within both the circuit and the battery itself, which is why short circuits are a bad thing!
 
Orionaut said:
Interestingly, in the early days of electricity. "Voltage" was indeed refered to as "Pressure"

It is actually a pretty good analogy. (Which you clearly understand quite well)
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Its not a perfect analogy, but for a mechanical man such as myself it makes the whole thing slightly easier to understand, even things like attenuation can be explained by thinking of the liquid as being slightly compressible, resistance equates to pipe friction, etc etc.

It falls apart when you start to look at things like load lead/lag and apparent power vs actual power in ac systems, and it completely fails at 3 phase, probably explains why i'm terrible at understanding both of those.
 
NoNameNoNumber said:
By the time you come to needing to understand lead/lag, capacitance/inductance etc etc you probably shouldn't be relying on analogies though :D
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Capacitance i can get, if only by understanding the physics behind it, sort of managed inductance the same way. Ac still messes with my head though.

That said i'm not an electrical engineer, so i guess i know enough that what i don't know needs someone who's actually able to understand such things and what i do know will cover me pretty well.
 
Devrij said:
whole circuit as though there was only one battery.

But that isn't the case so where am I going wrong here?
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You don't have a circuit unless you connect positive to negative, with something in between to use the electrical energy.
You will get resistance but that is more over long distance.

Volts and amps are also not mentioned, volts are electricity amps are the push.

Bigger amps = Death.
Bigger voltage = Static electricity.

+ will always choose the fastest root to - either though you or anything in between.

Just don't mess with amps they the killer. :p
 
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