Generic Plastic Case/Housing for Three Vertical 18650s in a Triangle?

[YoshiMoshi]

I see lots of power tools arrange three 18650s in a vertical triangular fashion. Seems to be a pretty popular design. Does a generic Plastic Case exist for this arrangement that allows you to insert the cells and remove them quick and easily without having to spot weld? Looking to do some testing, would like quick insertion and removal of the cells.

 

[bananu7]

You would need some way to keep them tightly pressed to the contacts. I was actually working on a 4-cell circular case like that and had a lot of issues with spring contacts not being reliable enough. If you use some stiff springs instead of typical AA cell springs, though, i believe it can be made to work. It's an easy enough thing to 3D print.

 

[YoshiMoshi]

You would need some way to keep them tightly pressed to the contacts. I was actually working on a 4-cell circular case like that and had a lot of issues with spring contacts not being reliable enough. If you use some stiff springs instead of typical AA cell springs, though, i believe it can be made to work. It's an easy enough thing to 3D print.

I wonder if I could just use three holders outside of the battery case and tool and somehow wire them to to the connector of the tool, allowing for rapid testing to determine which cells are the best. Instead of previous option of a generic battery case that fits in the tool that allows for rapid removal and insertion.

 

[bananu7]

I wonder if I could just use three holders outside of the battery case and tool and somehow wire them to to the connector of the tool, allowing for rapid testing to determine which cells are the best. Instead of previous option of a generic battery case that fits in the tool that allows for rapid removal and insertion.

that's definitely an option. If you look on Aliexpress, you'll find a lot of accessories for that. There are ready-to-print 3D models of batteries for e.g. Bosch, there are triangular 3s BMS boards specifically for this purpose, there are connectors etc.