Well lets see.

I purchased these http://www.toolsforless.com/product/7364.html for 131.88

That gives me 20 cells 1500 mah a piece at 3.7 volts nominal.
131.88/20 is 6.60 per cell or to make it easier to compute battery to battery.
2 li ion cells in parallel are 3000 mah. That would be 13.20$
Let take a GP 3300 http://www.maxamps.com/index.html?lmd=38836.584491
6.99 a cell. 6.99 * 3 is 20.97...


3.7/1.2 is 3.08. So to get to 1 li ion cell you need 3 subC batteries.

Hope I didnt screw that up