Battery

Featherframe kits run on USB-C power and don't come with a battery. If there's no outlet where you want to hang the frame, a flat USB-C cable in a cord cover along the wall is the simplest answer. Or you can add your own battery.

USB or battery

	USB	Battery
New pictures	Right away	At the next check-in, from every minute to once a day
Charging	Never	Every few weeks to months
Firmware updates	Any time	At a check-in, if the battery is above 3.70 V
Cable	Yes	No

Add a battery

1. Connect a protected single-cell (1S) LiPo battery with a JST-PH connector to the driver board. The frame charges it over USB-C.
2. In your Featherframe webapp, click the frame in the Frames list.
3. Set Power to Battery.
4. Set Update interval. A longer interval makes the battery last longer.

The frame uses the new settings the next time it checks in.

Battery life

Estimates for a 2000 mAh battery and about 20 new pictures a day. The screen uses no power to keep showing a picture. Most of the power goes to Wi-Fi.

Update interval	Battery life
15 minutes	7–8 weeks
30 minutes	11 weeks
60 minutes	14 weeks

Quiet hours make the battery last longer.

Warning

If Power is set to USB while the frame runs on the battery, the battery lasts only 4–5 days.

Low battery

• Below 10%: the frame shows Battery low in your Featherframe webapp.
• Below 3.45 V (3.55 V on the EE02): the frame shows Battery low, charge me once, and stops using Wi-Fi until you charge it. The EE02 warns earlier because it needs more power to change the picture.
• Below 3.70 V: the frame doesn't install firmware updates.

Accuracy

The battery reading is accurate to about 2%. If you build the firmware yourself, you can calibrate it with FF_VBAT_TRIM. See VBAT_TRIM in firmware/include/ff_config.h.