A bit OT
volume of 18650 = 9mm x 9mm x 65mm (exterior) = 5,265 mm3
volume of 2170 = 10.5mm x 10.5mm x 70mm (exterior) = 7,717 mm3
If you watch the manufacture of a cylindrical vs prismatic Li battery, they are __both__ wound jelly rolls, a sheet with "goo" on 1 side.
the cylinder can be inserted into a cylinder, and capped
the prismatic is wrapped as an oval, then "smooshed" / "flattened" in a press, __hopefully_ without damaging the very this jelly roll then then smoooshed jelly roll is crammed into a rectangular prismatic case, with the voids(unused space) and such
just at an uneducated glance, the cylindrical looks more efficient, denser, less prone to rejects (you smoooshed this run just a bit too much)
(could this be a reason for a Bolts having battery pack, failures since I recall they use Prismatics and failures were low voltage of some modules
My Chevy Bolt Battery Died Twice At Under 12,000 Miles: Here's Why
how to make a prismatic battery jelly roll
prismatic smoooshed jellyroll
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Tesla cylindrical battery
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prismatic BMW smooshed