You're getting to the right answer, the hard way. No need to even do the
WHr

Series connection... =

Each battery supplies the *entire* load current for its portion of the
supply voltage.

Parallel connection
Each battery supplies the entire supply voltage, for a *portion* of the
load current.

If you look at the above two statements - you'll the the difference is
the current drawn from each battery. =

(In the case of two batteries the difference would be a factor/multiple
of two)

--------- Long winded analogy ----------
Imagine two tanks of water the same size... (batteries) =

             a hose....                                        =

(resistor)

Tank volume =3D charge.
Fluid height above ground =3D PSI or kPa =3D Volts (above ground)
Flow =3D Amps

Two tanks side by side =3D parallel
Both have the same height so the bottom pressure on the hose is the
height of one tank.
If you open the valve, water flows at the rate dictated by the size of
the hose and the pressure. =

The pressure drops as the level drops.
The height drops in BOTH TANKS at once, and the volume in each tank
reduces at half the flow rate.

One tank on top of the other =3D Series
The bottom pressure is now double that of one tank.
If you open the valve, water flows at the rate dictated by the size of
the hose and the pressure. =

The pressure drops as the level drops.
The volume reduces in one tank, then the other, at the flow rate.

So - series connection increases pressure (volts), but it will not hold
that for as long.
      - parallel increases capacity (level drops slower), but not
pressure (volts)


---------------------------------------------------------------------------=
--------------------------------------

>>> Tom=E1s =D3 h=C9ilidhe <toe@lavabit.com> 26 Jun 08 11:43:39 >>>
Byron Jeff wrote:
>
>> And let's say I put two of these in series to form a 3 V battery.
Will I
>> have a 3 V battery with 1500 mWh?
>>     =

>
> No. You'd have a 3V battery with 500 mAh 1500 mWh/3V =3D 500 mAh.
>   =


Emmm.... right let me try this again.

* I've got two batteries
* They're both 1.5 V
* They're both 500 mAh

Now, if the voltage is 1.5 V, then 500 mAh corresponds to 750 mWh.

One battery =3D 750 mWh of energy
Therefore two batteries =3D 1.5 Wh of energy

Ok so altogether I have 1.5 Wh of energy in these two batteries.

Now I put them in series and hide them in a sealed black box and tell =

everyone that it's a 3 V battery.

OK so now I've got a 3 V battery and I've got 1.5 Wh of energy =

altogether. That right?

Now, to go back from Wh to Ah, I divide by the voltage

    1.5 Wh  /  3 V   =3D  500 mAh

OK, so I've got a 3 V battery with a capacity of 500 mAh. That right?

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