I replaced iphone 6 logic board and home button with used parts (from a smashed phone I verified had been paid in full)....

i spilled a coke on my husband's macbook pro last weekend. I took it apart and there wasn't all that much liquid. Anyway,...

I was able to revive 3 iphones (5. 5s, and 6+) all presumably dead without hope, 2 had been in a drawer for some time.. I had taken each to Apple who tested and had told me logic boards were probably fried (Over the years they have replaced at least 4 phones under warranty for similar issue). I am assuming that a new battery would have had same result, but I had been told by apple that the battery was not the cause and I didnt have an extra one to try. I would suggest this as a last resort only . 1. Cut the micro usb connector off cable, strip the ends of the positive and negative wires (apple cord didn't work for me), I found it easiest to bend the tip of wire into a 90 degree or L shape 2. Disconnect the battery. You may want to remove battery from phone. Bend the cable to access connecter. 3. Quick google search for battery schematics to determine +/- pins on battery cable 4. Before plugging in position the positive and negative wires to respective pins on cable 5. Plug cable in and charge battery...

I agree replacing the battery is the best solution, but if you dont hve a battery and need immediately, you can charge the battery directly for a short whille, close phone, and it may possibly then resume charging through port. If this works you can't let the battery fully discharge again or the same thing will occur again (im assuming youve checked port to make sure its lint/dirt free)

Did you pop the J key off to make sure there isn't just something stuck under there?