Flexing 18650 battery bracket with integrated spring

This is a cut-off and slightly modified version of the original design by enif. I designed this for building battery packs out of 18650 cells, where the cells are most efficiently stacked in a staggered pattern.
I have not actually built a pack out of these yet, since I've just made my first functioning prints.
I'm printing in PETG, but ABS should also work. PLA may be too stiff. Use 100% infill.
Batteries should be inserted near the spring where the thing is most flexible, and then pushed towards the flat side.
Unfortunately I don't know enough about OpenSCAD to make this parametric like the original.