Overview

This is a simple lithium battery charge controller for use with 3.7V lithium ion and lithium polymer batteries. The PCB is marked for easy soldering. 

To charge an attached battery either plug a mini USB cable unto the board or use the IN + and IN - solder points with a voltage between 4.5-5.5V DC. The board has a maximum current rating of 1A and uses linear charging. The board uses two small LEDs as indicators, with RED during charging and BLUE when the battery is full.

Warning: Lithium batteries are in nearly every gadget we use and are, in general, safe. However they can start a fire or become deadly if handled improperly.