Question

By how much does exp point power lvl 1 increase the exp that you gain per battle?

Answer 1

Exp.Level 1 increases experience by 20%, Level 2 by 50% and Level 3 by 100%

A simple way to say this is level 1 gives 1.2x. Level 2 gives you 1.5x and Level 3 gives you 2x

Source: http://www.serebii.net/xy/opowers.shtml

Hope I helped!

Answer 2

1.2x. Level 2 gives you 1.5x and Level 3 gives you 2x.

Source