There are two ways to power your Feather:
1) Power with a USB Cable connected to a power source.
2) Connect a 4.2/3.7V Lithium Polymer (LiPo/LiPoly) or Lithium Ion (LiIon) battery to the JST jack. This lets you run the Feather without wires, untethered!
If you're running off of a battery, chances are you want to know what the voltage is! That way you can tell when the battery needs recharging.
In this section, you'll connect a battery to your Feather, and configure a battery monitor component from Adafruit IO to report the board's battery voltage and charge percentage.
The Feather's MAX17048 Battery Monitor is located directly above the STEMMA port, highlighted in pink.
You can plug any 250mAh or larger 3.7/4.2V Lipoly battery into the JST 2-PH port (identified in the diagram below) to power your Feather and charge the battery. The battery will charge from the USB power when USB is plugged in. If the battery is plugged in and USB is plugged in, the Feather will power itself from USB and charge the battery up.
For more information about powering your Feather, visit the Power Management Page in this guide >>>
From your device page, click the New Component (or +) button.
From the component picker, select the MAX17048.
On the Create MAX17048 Component form, there are two options:
- Enabling the battery cell voltage reading will cause the Feather to report the status of its battery expressed in Volts.
- Enabling the battery cell percent reading will cause the Feather to report the status of its battery expressed as a percent.
Then, the battery measurement will be read and sent to Adafruit IO every "Send Every" period.
In the screenshot below, we've configured the battery monitor to report its battery cell voltage and percent to Adafruit IO every 30 seconds.
After configuring the MAX17048 component, click Create Component.
Every 30 seconds, the Feather uses the MAX17048 component to measure its battery cell percent and voltage, and report it back to Adafruit IO.
Now that you have a battery monitor component set up on Adafruit IO, follow this guide to configure Adafruit IO Action for receiving an SMS when your Feather's battery level is below a threshold.