USB Quick charging box (3516/3518)

thingiverse

A bit of a rough design for a charging box designed around the 3518 QC4.0 charging module. The design could be done more elegantly but maybe someone will find it useful as it is. A design goal was to avoid having to use supports. I've added the F3D file as well so go ahead and improve it :) The supply voltage can vary between 6 to 35 V. But in order to get maximum charging effect the voltage must be above 21 V. The box has slots for inserting 8 modules. The slots are a tight fit in order to avoid the modules from sliding around too much when inserting USB cables. I've added a fan to my box which I've hot-glued to the backplate because the modules get HOT(!) without it when charging with max effect. A On/Off cutout hole for a button has also been added. I'm using the button as a master switch to turn the box on or off. The assembly process is; 1) Solder wires to the modules 2) Slide the modules in place. 3) Add (glue) the 'backstoppers' in the holes in the main box. 4) Fix wiring (modules/button/fan) 5) Glue the top lid in place. 6) Optional: Glue a fan to the backplate. 7) Glue the backplate in place. The parts list: 1) <a href="https://www.aliexpress.com/item/1005001571432060.html?spm=a2g0s.9042311.0.0.27424c4dFhyQoe">3518 QC4.0 Module</a> 2) <a href="https://www.aliexpress.com/item/32806570916.html?spm=a2g0s.9042311.0.0.27424c4dikIxNX">10 x 15mm On/Off button</a> 3) <a href="https://www.aliexpress.com/item/1005002846853084.html?spm=a2g0o.productlist.0.0.10824fc73tIfuE&algo_pvid=43ac02d7-4aae-4936-bf89-83faa9aa3d38&algo_exp_id=43ac02d7-4aae-4936-bf89-83faa9aa3d38-3&pdp_ext_f=%7B%22sku_id%22%3A%2212000022446393944%22%7D">LM2596 step-down module for fan</a> 4) A fan