I’m building out my on-wall android tablet project as many other have before me. I looked around to see if there was any way to have HAOS enable/disable charging so the tablet battery doesn’t get trashed. But the consensus is that it’s not possible programtically.
That has led me to the idea of having a small (micro even) esp32 board that esphome could have HAOS monitor the tablet battery level and enable/disable a USB power passthrough to charge the tablet following the 80/20 approach.
I have seen there are TI chips that act as a USB relay but not being super electronics-designer skilled, I’m not sure how to go about designing the board or writing the ESPHome code to drive it.
Now, I can’t be the only one that has thought of this. Is there possibly something already on the market that would take a USBc power in and provide a switchable USBc power out that can be hooked into HAOS? Preferably something small enough that could be mounted into a slim wall mount for a 10" tablet?
PS: before you commit, most modern-ish tablets have some kind of battery overcharge protection setting you can enable. Depending on your tablet, you might not need any extra hardware at all.
My bigger TabS7+ does have that, but I don’t think the Tab8a has that feature. I’ll double-check that.
What it doesn’t have, though, is the other end of the equation. It will stop charging at 80% but not let the battery drop to 20% like a regular charging cycle would.
@tmo The tablet is getting mounted on the wall with a recessed outlet behind it. The outlet has USBa and USBc ports to power the tablet from behind. All neat and hidden. A smart plug won’t fit back there without making the tablet mount hideously huge!
I haven’t found any remote outlets let alone any with USB ports integrated. Unless you know of any, preferably Zigbee or Z-Wave?
I wouldn’t worry about it. Even if you do a 100% / 25% charge/discharge cycle every day the battery would still have more than 75% of its original capacity after 12 years.
