That would depend on the nature of the battery. If it had low internal resistance and was capable of providing enough current to destroy the LED, that would be bad no matter how little the LEDs were used. If the LEDs were driven hard enough to shorten the amount of time that they were capable of delivering full brightness, that could also be bad.What would you sat the risk of destroying my blue and green LEDs is if I don't use the resistors and connect then straight to the battery keeping in mind that I will only be powered for short periods of time max of 1 min a couple times a day.