AFAIK, Batteries in pokemon cartridges were only for the in-game clock, not the actual save files! So he is not safe!
Edit: i stand corrected! Ive never had or worked with pokemon carts specifically, but i have worked with & modded a lot of GB, GBA and N64 carts and not all of them have batteries, in fact most dont. I know n64 mempaks do, tho, but almost none of the carts. Info i had gathered from the various retro communities led me to believe that GB/GBA pokemon carts were a type that didnt need a battery for the save file, only the clock, but apparently that isnt always the case!
![Regret [Elder Cactus]](https://startrek.website/pictrs/image/b81bb97d-6413-4b36-9304-003f0bec8198.png){kind=link}
AFAIK, Batteries in pokemon cartridges were only for the in-game clock, not the actual save files! So he is not safe!
Edit: i stand corrected! Ive never had or worked with pokemon carts specifically, but i have worked with & modded a lot of GB, GBA and N64 carts and not all of them have batteries, in fact most dont. I know n64 mempaks do, tho, but almost none of the carts. Info i had gathered from the various retro communities led me to believe that GB/GBA pokemon carts were a type that didnt need a battery for the save file, only the clock, but apparently that isnt always the case!
Definitely not true for gen 2, and I imagine gen 1 was the same. I had to change those batteries with a melted pen.
The old gen from gameboy/color need battery for the save file too.
I think that depends on which Pokemon game