18650 Charger - 8x Batteries (Remix)

thingiverse

EDIT 1: After printing (About 5hrs) I realized my mistake with the holes for the step-down converter, which is this OSKJ:\r\n\r\nhttps://www.aliexpress.com/item/DC-CC-9A-300W-Step-Down-Buck-Converter-5-40V-To-1-2-35V-Power-module/32639621677.html?spm=a2g03.10010108.1000001.8.73561633nzHHby&isOrigTitle=true\r\n\r\nThe holes for the screws are completely off, and also the little tab for the switch is too small to allow the heatsinks and switch to be mounted together, but I'm not worried, it's working, slowly charging my salvaged batteries.\r\n\r\n\r\nEDIT 2: Added V4 File. I redesigned the thing, now it fits perfectly with the step-down converter and saves a bit of material, I also realized I don't need the two charging boards, since I can adjust the constant current and constant voltage with this step-down converter, so I can connect it directly to the batteries respecting its charging currents limitation, using a safe current value of: \r\n(BatCapacity * 0.4) * NumberOfBatteries\r\nAnd voltage set to 4.15V\r\nBe cautious with this setup, overcharging or overcurrent your batteries may cause severe damage! \r\nAlways pay attention if the batteries aren't getting hot! It's a bad sign, normal batteries don't get hot while charging properly.\r\n\r\n==========================\r\n\r\nI'm too impatient to charge 4 batteries at a time, and I had some cool stuff lying around, like a step-down converter, a notebook charger, and a switch, so I made this to charge up to 8 Batteries using two Chinese modules, the step-down and the notebook charger. It's nice and useful, but it may explode, so be careful haha