I could just leave the heading here, and that would suffice. Really, save batteries were probably the best things for gaming alongside the NES, and we still benefit from their beneficence today.
“Beneficence” isn’t just used there for snazzy word choice either, as most parents would probably agree, because there is a kind of obligation developers have to make their games actually playable long-term without completely imploding.
Prior to The Legend of Zelda, almost every game had no way of letting you continue your fun. Some arcade cabinets had a kind of suspend feature that let you pop more coins in for additional fuel or whatever to continue going, but there wasn’t any real way to actually back up your progress.
The lines blur a bit as far as who actually innovated with the idea of battery-powered save files. Pop and Chips, a 1985 game on the Super Cassette Vision utilized a literal battery save, where the feature used two AA batteries to power the save file.
Why Pop and Chips used this feature is a little less clear. It’s essentially the same kind of game as Bubble Bobble, not exactly requiring suspended or saved data for progression purposes. However, Nintendo’s Family Basic programming tool for Famicom games used a similar AA battery-powered feature a year prior to Pop and Chips, though of course, a programming tool and an actual game are two different things.
Regardless, fast forward to 1987’s release of The Legend of Zelda, and Nintendo offers something in that cartridge that would stick around for a long time: a CR2032 battery that lets you record your progress. Games like Zelda would have been nigh-on impossible without this feature, though Nintendo didn’t adopt it full force for a while yet.
Many — too many — SNES-era games relied on password systems that half the time never worked, much to the chagrin of players and parents the world over. However, as the era progressed and transitioned into the next generation of gaming, the save battery sparked changes. Some games used the little CR2032, while others such as Neo-Geo and Sony looked to memory cards for saving salvation.
The Xbox was the first system to use built in memory, and that pretty much takes us where we are today, with systems packing various degrees of internal storage and almost completely removing the need for any kind of external backup — except Nintendo, ironically. The Switch absolutely needs an SD card for storage thanks to its teeny 32GB internal storage system.
Still, the save battery led to these developments and made possible all manner of gaming experiences we never would have had otherwise.