It's not that confusing... once you've done it.

Let's say you have TWO identical 3200mAh 3S LiPo batteries. Each only produces 11.1v nominally.

If you use one of these: [link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXNKY9&P=ML]Click me for Series Adaptor[/link]

The TWO batteries will behave like one 3200mAh 6S LiPo producing 22.2v.

The higher voltage will turn the motor over faster ( if it can handle it! ) and produce higher power output... only if your ESC and motor can handle the voltage.

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You can also wire two batteries in parallel.

Let's say you have TWO 2200mAh 20C 11.1v LiPo packs.

These are each capable of at maximum producing 44 amps of current, but you'll be pushing the batteries pretty hard if you attempt to draw this much current from them.

Let's say that one pack gives you 8-10 minutes of flight time.

Well you can use one of these: [link=http://Click me for Parallel Adaptor]http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXNKY8&P=7[/link]

To combine the packs to work as one big 4400mAh 20C 11.1v LiPo pack.

Now the combined pack will sustain up to 88Amps ( if you push it of course ) or it will loaf along at 44 Amps!

In addition your 8-10 minutes of flight time gets doubled to 16-20 minutes of non-stop flying.

( I did this with my SuperSportster EP and I get 30 minutes of flight time out of it non-stop! ).

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You can also combine Parallel and Series adaptors for even bigger installations.

So with one of each of those adaptors and FOUR 2200mAh LiPo packs you get the effective output of having one massive 4400mAh 22.2v 6S battery pack capable of 80A.