Ive got a level 50 brotherhood battle mage with 75 destruction, 50 illusion, 100 conjuration, 100 sneak, 80 archery, and 80 one handed. Hes also a vampire lord. Ive got enchanted weapons with the magic power perks, and I three hit gaurds on expert. Hes pretty strong but useless against dragons. I feel like I'm at a road block. Ive got warriors with enchanted armor that bone dragons with close to no problems. I havent even been playing with him because I feel like hes obsolete. Its a shame because hes a fun flexible character.

It sounds like defense is your problem. I would recommend getting high elemental resistant gear. It doesn't seem like you have any skill in Armor, so I don't know the effectiveness of that. Maybe Conjure up a Dremora Lord and get to a nice hiding position and get in some Sneak attacks with bows.

Are they killing you too quick with their breath attacks?
If yes then you need magic resistance.

I've always figured a battlemage to be a heavily armored spell plinking character, also slashing and bashing should there be a need for it.

You need to lvl up you alteration and restoration skills. Then add Necromage perk, Atronach perk and activate Atronach stone. This way you'll have 100% spell absorption. Also flesh spells can help you with you armor rating (if you didn't reach the cap. Othe useful perks: Recovery, Regeneration, Avoid death (you can reach up to 500 Hp recovery with Regeneration and Necromage), Magic resistance (only useful against revered and legendary dragons - they have the only magical attack that can't be absorbed), Stability (if you need to use flesh spells).

Also, if you dual wield, Dual furry is boosted by Necromage perk, adding a lot to your attack speed.

You have to get the perks (and not only perk, other active effects like Agent of Mara and armor enchantments are boosted by Necromage) after you have Necromage perk + Vampire.

If you decide to take this route, 100% spell absorption may prevent you from using conjuration spells.

What type of gear are you using? You didn't mention any armor skills

Hey OP, May I asked why you leveled Sneak, Archery, and Illusion? Leveling and perking One Handed could be debated, but I personally don't see Battlemages using Sneak, Archery, and Illusion. Also what are your stats?