18650 Four-Cell Pack Jig
A 44 mm square block with four through-bores (18.7 mm, on 20.6 mm centres) that holds four 18650 cells upright, parallel and bottom-flush against the bench so nickel strip lands square during spot-welding or pack glue-up. Open-topped grab notches — one per cell, in 4-fold symmetry — let you spin a cell to set polarity, and two 5 mm ears with M3 clearance holes bolt the jig to the bench; overall 68 x 44 x 26 mm.
electronics 18650 battery jig