Tonight

[Knobhead]

Before you all carry on bickering, have a look at two definitions AHr and AHrV.

 

[happysteve]

Before you all carry on bickering, have a look at two definitions AHr and AHrV.

From Wikipedia, the free encyclopedia:

-----
An ampere-hour or amp-hour (SI symbol A·h or A h; also denoted Ah) is a unit of electric charge, equal to the charge transferred by a steady current of one ampere flowing for one hour, or 3600 coulombs.
-----

Couldn't find "AhV" or "AhrV" but VAh is (assuming no reactance) Wh (Watt hour) which is a unit of energy, equal to 3.6kJ (see post #44).

I have an inkling of where you're going with this, but I'll let it play out...

So, let's remind the class of the problem:

We have four 1.5V batteries. Each battery has a sticker saying "3Ah" on the side.

I assert that if you connect these together in parallel, you have a 12Ah 1.5V battery.
The total energy stored in that battery is 12Ah x 1.5V = 18Wh = 18VAh (or 18AHrV if you like) = 64.8kJ.
The total electrical charge in that battery is (12 x 3600)C = 43,200C (coulombs).

As far as I'm aware, there isn't any disagreement there (please pipe up, anyone, if you disagree).

I also assert that if you connect these together in series, you have a 3Ah 6V battery.
The total energy stored in that battery is 3Ah x 6V = 18Wh = 18VAh (or 18AHrV if you like) = 64.8kJ.
The total electrical charge in that battery is (3 x 3600)C = 10,800C (coulombs).

Anyone disagree?

 

[HandySparks]

Before you all carry on bickering, have a look at two definitions AHr and AHrV.

No bickering Tony, just a few chaps keen to ensure that the basic physics here is correct, even while the regs, best practice, etc. are open to interpretation and debate.

Assuming that you're referring to "Ah" and "VAh":

Ah is a measure of electric charge. 1Ah is equal to 3600C (coulombs). 1C = 1A x 1s.

VAh is a measure of stored energy. More frequently referred to as Wh. 1Wh is equal to 3600J (joules). 1J = 1W x 1s.

Neither are a measure of power.


The above ignores any issues of change of capacity with discharge rate, change of voltage with charge, etc.

Happy to be corrected. Others may wish to elaborate on this.



Edit:
I see that happysteve has posted while I was mulling over my reply!