for applications like that your should remove the battery and put small cheap circuit that emulates it. then you can run such server very very safe, unlike with 100x batteries always harging.

Bot farms works that way.

This is fascinating, I never even considered this need.

Could you say more about this? What kind of setups work well? Is this really straightforward or are there any subtleties?

Took me hours to replace the battery in a pixel. They make it almost impossible to open a phone without breaking it. I can't imagine doing that for more than 2 phones

What else have bot farms learned through scaling?