I remember back in the 80's there was a push for 48 or higher voltage, Like the move to 12 volt from 6 volt in the 50's, there are good reason for and against.
When you exceed about 50 volts DC you are in to the area where electricity can pass through the skin.
If you want a visual, try and arc weld with 12 volt battery, 24 volts you can easily and 48 would arc much further.
48 volt nominal is almost 53 volts running.
48 volts is nothing new, I worked on and around it in industrial machines. There is good reason it hasn't been adopted into automotive.
When you look at all the disadvantages and then compare to the advantages, it so far has not panned out to be worth the switch. Things like switch and relay air gap have to be increased, arc suppression may be needed. Things are bad enough in a crash with 12 volt, imagine 50volt+ arcing everywhere.
My 6 volt stuff still works and starts when sitting in 0 deg F weather. Yeah, 12 volt holds some advantages, but not enough for me to change what worked close to 100 years ago.
