Cheap power bank DIY

Overview

If you are planning to build your own power bank this video is a must to avoid rookie mistake which I did down the road!

I wanted an cheap, small emergency power bank that wouldn't drag my pants down, so I set out to build an ultra-compact charger just big enough to boost a phone or charge AirPods.

Minimal requirements

• some cell (I picked 18350 Lithium-ion cell 1200mAh)
• some manager (I picked LX-LBC 3.1 module based on IP5310)
• some case (preferably 3D printed)

Features

• Ultra-Compact Footprint: Designed to clip onto a keychain or slip effortlessly into a pocket without the bulk of a standard half-kilo battery.
• Emergency Capacity: Delivers just enough juice (1200mAh) to boost an iPhone from 0 to 30% or fully charge wireless earbuds.
• only one USB-C (bi-directional): Stripped of unnecessary displays, flashlights, and legacy ports, it uses a single modern port for both charging and discharging.
• High-Current Output: Capable of handling over 15W/3A charging, providing surprisingly fast speeds for its tiny size.

Conclusion

For V2.0, there is plenty of room for improvement: I need to add proper airflow holes for heat dissipation, double-check my 3D case dimensions for a clean snap-fit, and finally integrate a direct USB-C male plug so I don't have to carry a separate cable.

WARNING⚠️ Batteries store a lot of energy. If handled improperly, they can cause fires or serious injuries. Always practice safe electronic habits!