Get a battery on hand but wondering how much power left? Why not try our Battery Detector. Just connect your polymer lithium battery to the JST connector of the board, you can easily know the probable power percentage.
The battery detector is able to work when the input voltage range is 3 to 4.2 volt. With the 3 on-board JST socket (1 x JST 1.0, 2 x JST 2.0), it can detect most batteries. If your battery’s has neither JST 1.0 nor JST 2.0 connector, don’t worry, there are 2 battery soldering pad which make the detector adapts to those battery with different connector. Once you connect a battery to this detector, the 4 on-board LEDs will indicate the remaining power by percentage range (0–25% x1, 26–50% x 2, 51–75% x 3, 76 –100% x 4). If you plug the connector in a wrong way, a fifth LED will be on.
Visual indication on remaining power of a battery
Different JST sockets for different battery connectors