Note: this is long winded but please read the part in bold if you don't have patience :lol:
Of course you could size your pack to be large enough to handle the load. It's just that you will need an obscenely large pack to deal with the load and not shorten the life of the cells in the process. Whereas you could use a 5AH nanotech pack or 15AH 20C RC Lipo to get the same power output as say, a 60AH panasonic pack.
Look at how Tesla Motors designs their packs. They design their cars around a 0.5C or lower continuous average load with cells that are very similar to these in output. Yeah, they can burst up to around 5C but they also have to liquid cool the cells to prevent them from exploding when they do that. That adds weight and price. And they can only do those short bursts of 3-5C power for seconds at a time. Put the Model S on a track and it will overheat just like the Roadster did whenever Tesla handed it to an automotive magazine.
If you have long hills to climb, you can hit this 'burst' power for long periods of time on an ebike. That's a problem for a cell that is being extremely stressed.
I don't think anyone here is going to tack on multiple pounds and cost to their pack to add thermal cooling so that they can push a wimpy high energy/low power cell to burst for longer periods of time. You can do 3C or above with liquid cooling but the voltage sag would be horrendous. The more realistic scenario is to use the pack for no more than 1C, and only use these cells if you want a really long distance pack.
I get pissy when i am pushing a 3C load on my 20AH 20C 10S pack and my voltage drops from 38.5v to 38v. Imagine hitting the throttle and putting 3C on a 20AH panasonic pack and seeing the voltage drop from 38.5v to 35v, and your top speed being lowered by 10%.. that just sucks.
Take the same situation in the winter where IR for my RC Lipo pack and your Panasonic pack has increased by 3x.
My lipo pack drops by 1.5v at 3C, and my voltage is 37v.
Your panasonic pack drops by 10.5v at 3C and the voltage is 28v.
One of the cells in the panasonic pack in this situation will hit the 2.5v cutoff point early and the BMS will cut the pack off early, with 25-40% capacity still left in the pack due to the voltage sag. Now in addition to heaving a cooling system, you need a heating system to get around this. Add more cost and weight.
Whereas the higher discharge cell needs none of this heating/cooling business as there is tons of headroom in the discharge spec to reliably run in extreme heat or extreme cold.
By the way, as cells age, their internal resistance gains. The panasonic pack will become saggier over time. Whereas the high discharge cell has plenty of headroom in it, so when it gains internal resistance, it isn't hit as badly as the low discharge cell. Which pack is more likely to achieve the promised cycle count if pushed to 3C?
