
Adafruit LiIon or LiPoly Charger BFF Add-On for QT Py
The Adafruit LiIon/LiPoly Charger BFF is a compact battery charging add-on designed to mount directly onto the back of any QT Py board. It makes portable power simple — plug in a standard 3.7 V/4.2 V lithium battery, and the charger handles the rest via the QT Py's USB-C connection.
When USB is connected, the charger tops up your battery at up to 200 mA (yellow LED indicates charging). When USB is removed, battery power feeds through a Schottky diode to the 5 V rail. A built-in slide switch lets you turn power on and off, and a voltage divider on pin A2 lets your firmware detect whether the board is running from USB or battery.
Key Features
- 200 mA Charge Rate – Charges single-cell 3.7 V/4.2 V LiPo/LiIon batteries via USB-C
- Automatic Power Switching – Schottky diode routes battery power to 5 V rail when USB is disconnected
- On/Off Switch – Built-in slide switch for power control
- Battery Monitoring – Voltage divider on A2 pin for detecting USB vs battery power mode
- Charging Indicator – Yellow LED lights during active charging
- BFF Form Factor – Solders directly onto the back of any QT Py for a compact stack
Ideal For
- Making any QT Py project portable with battery power
- Wearable electronics requiring rechargeable batteries
- IoT sensor nodes with battery backup
- Compact prototypes needing USB charging capability
Package Contents
- 1× Adafruit LiIon/LiPoly Charger BFF (assembled and tested)
- Headers for soldering to QT Py
Original: $10.22
-70%$10.22
$3.07Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
The Adafruit LiIon/LiPoly Charger BFF is a compact battery charging add-on designed to mount directly onto the back of any QT Py board. It makes portable power simple — plug in a standard 3.7 V/4.2 V lithium battery, and the charger handles the rest via the QT Py's USB-C connection.
When USB is connected, the charger tops up your battery at up to 200 mA (yellow LED indicates charging). When USB is removed, battery power feeds through a Schottky diode to the 5 V rail. A built-in slide switch lets you turn power on and off, and a voltage divider on pin A2 lets your firmware detect whether the board is running from USB or battery.
Key Features
- 200 mA Charge Rate – Charges single-cell 3.7 V/4.2 V LiPo/LiIon batteries via USB-C
- Automatic Power Switching – Schottky diode routes battery power to 5 V rail when USB is disconnected
- On/Off Switch – Built-in slide switch for power control
- Battery Monitoring – Voltage divider on A2 pin for detecting USB vs battery power mode
- Charging Indicator – Yellow LED lights during active charging
- BFF Form Factor – Solders directly onto the back of any QT Py for a compact stack
Ideal For
- Making any QT Py project portable with battery power
- Wearable electronics requiring rechargeable batteries
- IoT sensor nodes with battery backup
- Compact prototypes needing USB charging capability
Package Contents
- 1× Adafruit LiIon/LiPoly Charger BFF (assembled and tested)
- Headers for soldering to QT Py























