There is a maximum of 48 Bots for Team 1 (Axis usually), Team 2 (Allies) has no limit.
It works like this: With a Bot Ratio of 100, the number of Bots set by the slider (48 max in the slider) will be assigned to Team 1, Team 2 will recieve the rest.
The number of Bots you set in the launcher will ignore the slider settings, however the game still assignes the bots to the teams according to the slider settings.
So, to get the right balance of bots and make your matches the most enjoyable, I'd advice to follow my simple guide here:
It is kinda complicated to get the point across on this issue, but I hope I could make it somehow clearer.