It was a brutal and inhumane battle. Stalin left the army there to defend to the death. They were wiped out, but put up a Stalingrad like defense which slowed the German offensive and saved Leningrad and Moscow.
The T34 was, and remains a legend. The T34 (84,000 produced) which were built by women in the backfront, came as a nasty surprise, for overconfident nazi German troops.
The tank a combination of a perfect armour (thick and highly sloped), efficient gun, good speed and autonomy, sturdiness, easy manufacturing and maintenance.
They played a main role in the great battles of WWII: Kharkov, Kursk and Stalingrad, when the army of Von Paulus capitulated ...