Power Bank Module 5V 2.1A – DIY Lithium Battery Charger & Step-Up Boost Circuit for 18650 / Li-Po

Overview

The DIY Power Bank Module is a high-efficiency power management solution that combines a battery charger and a DC-DC boost converter. Designed for 3.7V Lithium-based batteries (18650, 21700, or Li-Polymer), this board boosts the voltage to a stable 5V for charging smartphones, tablets, and other USB devices. It’s the perfect recycled-tech project for students looking to reuse old battery cells safely.

Key Features 

• Dual Functionality: Charge your batteries via Micro-USB/USB-C and power your devices via USB-A simultaneously.

• Smart Protection: Built-in Lithium protection IC prevents over-charging, over-discharging, and short circuits.

• Status LEDs: Integrated 4-level LED indicators show the remaining battery capacity (25%, 50%, 75%, 100%).

• Plug & Play: No complex programming required. Simply solder your battery (B+ and B-) and you are ready to go.

• Auto-Wake: Automatically detects when a device is plugged in and starts the charging process.

Technical Specifications