Some more Ecotric Silverfish pics. I finally found that the cells are in a shrink wrapped package, held in the case by friction. It's like removing handlebar grips. A little soap and it could be pushed out.
With the shrink wrap peeled back, I found 50 cells in a plastic form plus a BMS circuit.
WIth further teardown, you can see the conductor plates on the ends of the cells and the plastic form. What's missing between this pack and a higher end pack is (a) better quality cells, (b) individual cell fuses and (c) perhaps a better BMS. Still, it looks like a well assembled battery. Not bad for a $779 ebike.
