No, he would need to be 2nd level, (Arcane Bolt, a universal spell, costs 2 PP), thus you would need 7 ranks minimum for a 2 PP spell using Battle Runes.
The 7th level thing would be for using Battle RUnes with non-Universal spells.
And don't forget, the real purpose behind Battle RUnes is to allow non-casters a way to work with some spells (or spells that one normally does not have access to).
Normal Runes could be used else wise.