After replacing the battery is dead!

My iphone have a seawater damage ( only from the center of the iphone to the dock,like 2 inches), I put it in rice and then it turn on in DFU mode only when I plug it. I try to restore it but then it turns off making the restore so I tink it was the battery, I replace the battery but now the iphone is dead, I conect it but the computer didnt recognize it, neither the itunes. How can I fix it?