20000 mAh Powerbank

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 !!!

Updates:

• 2022-02-04: Greater hole for iPhone plug
• 2022-02-10: Optimized PCB holder
• 2023-01-13: Include STEP files for remixing