The Blues lost 2-1 to their local rivals at the London Stadium in what was a scintillating match full of chances for both sides.
“The performance was good because we knew they would play a strong game, but I think we played with a good intensity and created many chances to score a goal,” said Conte.
“I saw a good spirit in my players because until the end they tried to change the result. Tonight we were a bit unlucky.”
Cheikhou Koutaye headed West Ham into the lead in the 11th minute before Edimilson Fernandes added a second just three minutes into the second half which prompted Conte to bring on Diego Costa, Eden Hazard and Pedro.
He added: “I think we didn’t expect the second goal so early and that changed our plan.
“Then we tried to change the situation by putting on fresh players. We created many chances to score and only did it at the end of the match.”