Car/Boat power - clean shutdown?

Hi

I have a Raspberry Pi boat monitor built on the bench, ready to deploy.

Boat has a 12volt system but in common with a car, it is either on or off. As it is remote, the power can come and go, indeed we often kill the power with the master switch when we leave. Therefore there is no concept of the Pi getting a clean shutdown. How well do they survive this or is there a way of holding some volts whilst it cleanly shuts itself down?

Hi. I just joined Pimoroni as I was looking for something similar online stumbled upon this thread. As for my opinion, they do survive quite enough but I am not sure about walmart codes. Definitely following this for sure.

It depends on what its doing at the time. If its reading or writing from the Micro SD card you could get corruption of the file system. Then it won’t boot up next time or you get all kinds of errors on boot.

I run a couple Pi’s headless on battery. I wire a push button to a GPIO pin to initiate clean shutdown when pressed. Then I just watch the status LED for the ten blinks, then turn the power off. I haven’t tried it but I’ve been told I can use the low battery warning pin on the Powerboost to tell the Pi to shut down automatically when the LIPO battery is getting low. I haven’t bothered because I never leave these devices running on battery for extended periods.

There are UPS type devices out there for the Pi. Google should hunt them up for you. How reliable they are, I personally don’t know.
https://www.google.ca/search?source=hp&ei=9lKeXI-dLKzH5gL0h7vgDw&q=pi+ups+hat&oq=Pi+UPS&gs_l=psy-ab.1.1.0l10.2559.4556..8099...0.0..0.100.550.5j1…0…1…gws-wiz…0…0i131.DY2kHw74Cf4