I know from this that "Battles Won" refers to the number of times your Pokemon has defended against an attacker at a Gym.
But I put my Pokemon in a Gym and immdietly I saw I already had 1 battle won, but no battle had taken place since I put it in the Gym.
Does this number reset ever? I did have this Pokemon in this same Gym earlier in the day. Will this number stay the same for each Gym or for all Gyms?
It's hard to see from this image, because the buttons literally hide the number but it says:
BATTLES WON: 1