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Inkplate 6 – Battery

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This page contains important information about using a battery with Inkplate 6. For safety reasons, please read this page carefully!

Inkplate 6 includes a 2-pin, 2mm JST connector that allows you to connect a 3.7V Li-ion battery. The onboard charging IC, MCP73831, automatically charges the battery when Inkplate is plugged into USB-C and switches to battery power when unplugged. A charging indicator LED provides real-time charging status.

Inkplate 6 battery JST connector
JST battery connector
Inkplate 6 Onboard charging indicator LED
Onboard charging indicator LED
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Get the battery polarity right. Check the markings on the PCB before connecting a battery. When orienting the JST connector with the notch at the top, the positive (+) terminal is on the left, and the negative (-) terminal is on the right.
Battery polarity on Inkplate 6
Battery polarity on Inkplate 6
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Battery polarity can vary! Some Li-ion batteries have reversed polarity. Connecting a battery with the wrong polarity may permanently damage your Inkplate! Double-check before plugging it in.

Compatible batteries​

Inkplate 6 is compatible with 3.7V Li-ion batteries with protection. If you purchased the Inkplate 6 enclosure and battery kit, it includes a 1200mAh 3.7V Li-ion battery with a built-in protection circuit.

3.7V li-ion battery with protection
3.7V li-ion battery with protection

Any of Soldered's 3.7V Li-ion batteries will work as long as they fit inside your enclosure.

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Due to shipping restrictions, we cannot ship Li-ion batteries outside the EU. If you're in the US, we recommend checking out Adafruit's Li-ion battery stock.

Check out our battery documentation page.

Charging IC (MCP73831)​

The MCP73831 is a single-cell Li-ion/Li-Polymer charge controller. It manages the whole charge cycle over USB so you do not have to. The chip uses a constant-current / constant-voltage (CC/CV) profile: a deeply discharged cell first gets a low preconditioning (trickle) current, then the full charge current until the cell reaches its regulation voltage, and finally constant voltage until the charge terminates.

On Inkplate 6 the charge current is set by resistor R10 (2.49 kΩ) on the charger's PROG pin. The datasheet's equation is I = 1000 / R_PROG(kΩ) in mA, which works out to a charge current of roughly 400 mA.

Key features:

  • Automatic charge termination when the battery is full
  • Reverse discharge protection, so the battery does not drain back into the charger
  • Thermal regulation, which reduces the charge current if the chip gets hot
  • Charge status indicator (connected to the onboard red LED)
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For full technical details, refer to the MCP73831 datasheet:

MCP73831/2 Data Sheet

Official data sheet for MCP73831/2 charger by Microchip