This is very much a WIP, and part of a larger 18650 BMS project.
It's a battery pack designed to allow combinations and multiples of 7 x 18650 LiIon cells.
The pack uses two mirror-image copies to clamp and hold 7 cells, and packs can be "stacked" together. Originally intended as a modular 14S battery pack.
The pack has slots at top, bottom and sides to allow max 10mm-wide nickel strips to be fed in so that they can join either/both adjacent cells and/or adjacent packs.
The 3D rendering shows a 14S assembly made from 2 7S packs.

There is also the first iteration of a fuse & connector box and a small clamp intended to hold an XT30 connector. This needs more work..