Incase you didn't note the question, it says "Energy" and not "Energy Cards"... Both of you above stated the maximum amount of energy cards, there are many combos/powers/bodies/special energy which exceed that. And yes, the limit only goes up to how many cards you have in your deck... so technically, like I said before, there is no limited rule on it. A pokemon can have as much as you want as long as your deck has 60 cards (normally)...