Repaired Charge Port - Works great, Replaced screen - Unit is dead

Afternoon All!

Successfully repaired the charging port on my kindle fire. It worked great for a couple of days so I decided to replace the cracked screen. After replacement the unit is dead. No charge indication at all. I have disassembled everything three times and nothing out of the obvious. I've tried two different chargers with no luck, both of them work fine on my cell phone.

So I'm guessing I either toasted the battery somehow during the screen replacment or I managed to mess up the repair/solder job on the micro-usb connector. Looking very closely at the connector I do not see the slightest hint of physical damage to the port. It's still mounted nice and firm.

How can I check the battery? Or does anyone have any other suggestions?