I am in the process of building an electric bike and all I need is the battery system. I am going to run it at either 36 or 44 volts, so 10-12s lipo or a bunch of a123 cells will do the duty. So far I have a big honking astro 90 and a "little" 3032 scorpion with appropriate OEMRC ESC. Both are rated at 1200w continous. I want to test the difference in efficiency between the systems and see which one works out for the best.
Now for the hard choice. Batteries! I would like to use lipo because it has a higher power density, and for my projected amp/hour rating it will only take 2 or 3p to get 10 to 15 amp hours. I would like to use a123 for the fast charging (if I have enough power

) and the longevity of the cells. The downside is that I will need 5 or more parallel banks for runtime.
What do you guys think about it? Charging seems to be the toughest part about the whole matter.