Techlevels unlock skill levels, higher levels of upgrades, and unlock armageddon missiles.

Techlevel Skill levels Faction Upgrades Weapon/Hull Upgrades
Tech 1 N/A N/A N/A
Tech 2 N/A N/A Level I (Groundbreaking Tech)
Tech 3 Rank 3, level 1 N/A Level I
Tech 4 Rank 2, level 1 N/A N/A
Tech 5 Rank 1, level 1 Level 1 Rockets/Forcefields/Torpedoes, Convoy, Advanced Colonization Level II (Groundbreaking Tech)
Tech 6 Rank 3, level 2 N/A Level II
Tech 7 N/A N/A N/A
Tech 8 Rank 2, level 2 N/A Level III (Groundbreaking Tech)
Tech 9 Rank 3, level 3 N/A Level III
Tech 10 Rank 1, level 2 Level 2 Rockets/Forcefields/Torpedoes, Titans, Prototype N/A
Tech 11 N/A N/A Level IV (Groundbreaking Tech)
Tech 12 Rank 2, level 3 N/A Level IV
Tech 13 N/A N/A N/A
Tech 14 N/A N/A Level V (Groundbreaking Tech)
Tech 15 Rank 1, level 3, Ultimate Level 3 Rockets/Forcefields/Torpedoes, Adv Refinery, Exp Armageddon Level V

Armageddon missile unlocks at Tech 20, and attempts to fire every tech level thereafter. You MUST control a Tech Lab in order to fire an Armageddon Missile.