20000 mAh Powerbank

20000 mAh Powerbank with 21700 Li-Ion Akkus

ATTENTION: Strictly avoid short circuit and wrong polarity

Part list:

- DIY powerbank modul 2.4A (e.g. from ebay) - 4 Samsung INR21700-50E (21700, 5000 mAh) - 4 hex screws M3 x 6 - 4 insert nuts M3 x D4 x L5 - 1 m flexible cable 0,75 - 1 mm² - 2 mm foam rubber

Printing parameters:

- Resolution 0.2 mm - 2 Perimeters - 20% Infill - Supports

Assembly:

1. Print all parts 2. Check fitting of knob 3. Check fitting of modul 4. Check fitting of holder 5. Check fitting of akkus 6. Insert nuts with solder iron 7. Plane contact surfaces of case and lid with sand paper (600, wet) 8. Connect all negative akku poles with 11 cm cable (see circuit plan) 9. Connect all positive akku poles with 11 cm cable 10. Solder cables to modul (13 cm positive cable, 21 cm negative cable) 11. Insert knob, modul and holder 12. Solder negative cable to akkupack 13. Pull negative cable loop and positive cable with a hook through center hole 14. Insert akkupack 15. Solder positive cable to akkupack 16. Add some 30 x 30 mm foam rubber pads 17. Close lid with four screws

Have fun !!!