I dont know if there was a post like this before but i wanted to know if there any huge battles ( not including the end of the main quest) that u could fight in, like a mod or a side quest.

I bet there is a multitude of mods that add large battles but I haven't downloaded such a mod yet myself. As for already existing battles, the only thing that I can think of wasn't even part of a quest. Somewhere north of Anvil I ran into a bunch of legionnaires close to an Oblivion gate that had appeared. There was about seven to ten legionnaires fighting a dozen or so Daedra, a mixed gathering of Scamps, Flame Atronachs, Clannfears and Daedroths. First I thought it was a mod but after the battle I talked to the captain of the bunch and it turned out that it was a part of the original game. Rather odd though, considering I had never ran into this confrontation with my earlier 10+ characters. Anyway, the gate appeared somewhere between the "County Kvatch" and "The Gold Coast" texts on the map. I don't have access to the game for the moment so I cannot give a more specific location.

no there is no big battles in the game perhaps the one at the end of oblivion but im sure there is with a mod or two that could help

Find mods that add more enemies... then get toaster's share mod... so you can recruit an army and go fight heaps of daedra...

What Rane is talking about is by Fort Sutch. Well, you could also steal a Goblin Tribe Staff (or whatever the name is), and put it in another Goblin lair.

I know that is part of the quest, but does that actaully work outside of that quest?

this is the fort sutch non- jounral quest

yes , it should do