thanks for sharing this method which i very ingenious and cheap, however it seems to require heatshrink to ensure nothing is moving in the battery
pack, this makes changing one of the cells not so easy... also i'm not sure there is sufficient space around the cells to allow air cooling. I keep thinking a solution based on modular plastic holders with integrated connectors has an interest !
I will try to take time to design a basic 18650 holder block in 3D to show what I have in mind
Do you know something better than Google sketchup to do that kind of work ?