iPhone 5s doesn't show that it's charging when its off

I was repairing an Iphone 5s. After I took the bottom screws out and lifted the screen,I was in the process of removing the metal shield from the battery cable.I used metal tweezers instead of the plastic sponger.Big mistake because I saw a small spark fly. I detached the battery,then held the power button for 30 seconds before reconnecting the battery.(In which the dead battery signal came on the screen).I then disconnected the battery and went moved onto the screen repair. Once I put the phone back together,I put the phone on charger.(At this point it is showing the dead battery signal.) I left it there long for about 5 minutes before the phone booted itself up. I tested everything to make sure everything is working, then I let it charge about 20 more minutes while connected to my laptop.The problem that I'm having is,the phone works fine,but when it is on the charger and turned off,it gives no sign of charging. If the phone is on while on the charger,it shows the lightning bolt by the battery at the to of the screen signifying charging in process. But when it's off,(though it's charging) it shows nothing but a black screen.Sorry so long, I just wanted to make make sure I included all details. Any help would be appreciated.