18650 Powerbank Tube Case

A compact and practical enclosure for your own 18650-based powerbank.
Built with affordable components and a clean, functional design.

🔧 Features:

• Securely holds a standard 18650 battery (65 - 69mm standard or protected)
• Designed to fit common, low-cost USB charging modules (~1 EUR on AliExpress)
• Tube-style body keeps everything neat and protected
• Screw-on lid for secure closure and easy access
• LED indicator holes to monitor charging and power status
• Intuitive assembly – easy to build, no chance of putting parts in the wrong way
• Requires a bit of soldering for connections — great as a beginner electronics project

Whether you're a maker, student, or just need a backup power source, this design gives you a solid, low-cost DIY powerbank that’s fun to build and easy to use.

🖨️ Print Settings:

• Nozzle: 0.4 mm
• Layer height: 0.16 mm (optimal)
• Supports: Not required
• Tested: with several different PLA's and Bambulab X1C and A1 

🧩Components:

• 18650 Battery Spring Contacts
  https://www.aliexpress.com/item/1005008239237846.html
   
• Type-C USB 5V 2A Boost Converter Step-Up Power Module
  https://www.aliexpress.com/item/1005006255126910.html
  
• Red Cable: 30mm
• Black Cable: 110mm
• Battery 18650: Length 65 - 70mm (with or with battery management)
• Heat shrink tubing for the plus side of the battery case (see picture)
• Heat sink, optional: 14x10mm

🧰 Assembly Instructions

      Cable soldering – important:

• Connect the red wire to the USB-C side
• Connect the black wire to the USB-A side
  

Insert the battery holder first into the tube — make sure the plus (+) side goes in first (follow the arrow on the case).

There’s enough room to insert the charging module and battery holder with the connected wires into the tube.

🧠 Tip: If it doesn’t slide in easily, don’t force it — double-check your cable routing and solder joints.

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