Found this Coin (Battery) at work this week. I have never seen one and thought it was interesting to what they call it. Just a lazy boring afternoon at home with nothing better to do!
Call it a coin battery because of the shape and thickness. CR 3032 is a popular battery. All my lit dot and reticle scopes use those batteries for illumination.
Looks like a crude cast fake, I doubt it would get graded. Not even a good fake, I am reporting the seller.
Virtually every computer built since the late 1980's contains one of those. It's the standard BIOS backup battery.