Quoted from Nokoro:
Unfortunately, I just don't understand. I'm not an expert in this. I don't think my laptop or desktop computers have a battery (well, the laptop has a rechargeable one). How does the desktop function if I've never changed the battery? As for keeping track of special features, pins should just have internet connectivity now like everything else so they can get the current time. Though, I suppose companies would start charging us more for that.
It is very simple to understand.
Your desktop and laptop both have these same batteries for the same purpose as the PC motherboard in WOZ.
WOZ is just a PC inside the cabinet with some extra add-on boards to interface with pinball parts like switches and solenoids.
WMS/Stern/DE/Spooky/TV remote controls/your motor car and millions of other devices use a different computer system called "embedded controller" and this does NOT rely on BIOS or batteries like a PC does.
Imagine if your car used a PC motherboard to control its many systems. It is a very bad choice for operating many of these types of things. Great for desktop/laptop systems but look at the problems most people have with them (PC's) on a daily basis. I have said it before and been shouted down but it is starting to come home to roost.