Ever since I got into building electric skateboards I’ve had a soft spot for ‘modular’ batteries, especially trying to keep things under 99wh. Now that the new Focbox Unity is soon coming out, I thought that it would be a great time to build a new board. Previously I’ve gone with NESE modules for modularity, but those things aren’t really plug and play but instead require a solid ten minutes of unscrewing to get the pack apart, plus they add quite a bit of extra bulk. So here is my possible solution, on which I’d really like some feedback on and would like to hear your thoughts, especially from more experienced battery builders than I, before I start spotwelding stuff up.
So basically what I’ve got so far are 10 ‘sleeves’ that fit seven 18650 cells in parallel that will be connected to each other via 5.5mm bullet connectors (for fast disassembly) to form 10S7P. This ‘design’ also also leaves me with a hollow canal between the two groups to run my wiring in, on the bottom of the enclosure. Each pack shall have a BMS balance connector and obviously two dangly bullet connectors originating from each side of the pack.
Would said 3D printed sleeves (ABS) still require the typical treatment of fishpaper around them, or would the tight fit of the 3D printed sleeve do the job? Obviously I’d still insulate the positive ends of each cell with those circly fishpaper bits before spot welding them together.
Why 3D printed sleeves you might ask? Well, to make the battery look less like a DIY C4 pack of explosives and more elegant and neat.
Wires would come out under the end caps of each pack. 5.5mm bullet connectors with 14AWG wire.