Here's the data sheet of the Sony V3 cells.
http://www.repasebaterii.cz/files/img/d ... 8650v3.pdf
They are imho the best cells for most ebike applications out there. Only for very small and high powered setups will I use the VTC4 over the V3 cells. E.g. for a 13s2p 4.2Ah pack for my folding bikes. The V3 are rated for 5c discharge and 1c charge rate. And over 90% capacity after 500 full cycles is absolutely amazing.
I would not go with Panasonic cells. They withstand less current, have less cycle life and are not drift free, so a balancer will be required.
@wojtek:
To be honest, LiFePo is an outdated technology that you shouldn't use on bikes anymore. Also, 18650 has become the standard in cell size, which you'll find in Laptops and even Tesla's cars. There's just too many downsides to using LiFePo, the only real upside being the price per kWh. But, weight, handling, cycle life etc are huge drawbacks.
Don't worry about the individual cells. They'll be joined together in parallel packs (in your case) of 9 each, that will work like one large cell, and then depeding on what voltage you need, I'll connect them in series.
The A123 cells are 7.273 kg/kWh and the Sony Konion V3 5.165 kg/kWh.
2.1kg or 40% more weight on a bike is a huge difference.
Just think how much people spend to reduce the weight of a bike just by a few grams on other components. Adding so much additional weight for no good reason is just wrong. If the budget doesn't allow for it, I would rather go with a smaller pack than using an inferior technology.
