I would like to add additional flight time to my Slow Stick I have recently built.

Right now I have one Thunder Power 2 Cell
1320 mAh 7.4 Volt pack. You can see it at:

http://www.hobby-lobby.com/thunderpower.htm

If I wanted to double my flight time, do you know if I could simply buy another one of these, combine
the two red wires and two black wires and be ready to go?

I have a Uberall Nippy brushless 1812/100 with a Jeti 18 amp brushless controller.

If anyone can help, it is appreciated...