Battery power for Pi Zero 2 W + 7.3" e-ink display

Discussion
1

Hi everyone,

I have a Raspberry Pi Zero 2 W driving a 7.3" e-ink display. Currently, the display refreshes once every hour via a script, and everything works fine when powered from the wall.

For convenience, I’d like this setup to run on battery, ideally autonomously for days.

Does anyone have ideas for a battery setup or wiring solution?
I’m looking for something that:

  • works with the Pi Zero 2 W

  • can provide enough current for both the Pi and the display

  • allows easy recharging

  • ideally can keep the Pi powered while charging the battery

Thanks in advance for any advice or experiences!

2

Read pi-e-ink-daily/Inky-Impression-Frame at master · bablokb/pi-e-ink-daily · GitHub and be sure to scroll down to skip all the sections about the frame itself (the battery part follows).

What I basically use is a LiPo and a boost-converter with an enable pin. The LiPo (an 18650) sits in the bottom of the frame, connected to a TP4046 LiPo charger:

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3

I am doing this with an Inky Impression 7.3” and a Witty Pi L3v7 hat on a Zero 2W. The battery is a 6600mAh from Adafruit. This works great as long as you do the SPI speed fix noted at Inky Impression 13.3" + Witty Pi + Raspberry Pi Zero W2 not working

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4

Very nice setup, thanks for sharing. The next thing you want to do is optimize uptime. Current draw is mostly dominated by uptime, and you can do a lot to speed up boot-time. I had written an article about what to do. It is more than five years old but most of it is still valid. Back then, I managed to bring down boot times of a Pi-Zero from 30 to 5 seconds.

The article is in German, but I guess some translation tool will happily swallow it. Anyhow, if you have questions, just ask.

5

Thank you, I’ll give this a read. My current boot time does seem quite long