how to get 2 battery in one esc ?
whatis that ?

You need to either make up or buy a series or parallel connector using matching connectors and suitable wire.....I don't have a picture to show but someone else may.
Good Luck
Steve

Two ways parallel conection and series connection. http://www.scriptasylum.com/rc_speed/_wiring.html

Check out Battery Pack Wiring

Angel Hell
Here's a pic of some adaptors.
The first one is for the batteries in parallel.
The second one is for the batteries in series.
The third one is for the batteries series but supplying two speed controllers.
Hope this helps a bit.
Paul.