S.Peelman said:
The batteries in old cartridges are easily replacable, they’re just regular watch or hearing-aid type batteries. At most over time you’ll lose your existing save. EDIT: Well, they do need soldering, but still. |
The battery can be replaced but, from personal experience, you'll lose all of your save data. My "101% DKC" save and my " Every character is level ⭐⭐" save in Chrono Trigger are evidence of that.