We use a Supercapacitor UPS hat to supply enough power for a controlled shutdown due to concerns over SD card corruption (you get around 1 minute). It's been re

We use a Supercapacitor UPS hat to supply enough power for a controlled shutdown due to concerns over SD card corruption (you get around 1 minute). It's been reliable on systems that regularly lose power over a period of around 5 years. The hat we use (Juice4Halt) is more expensive than the SBC though, so that is probably a non-starter for a lot of people.