Opened my MP charge hub up to determine the battery connector pin usage … since …
a) there was little chance of damaging anything
b) if anything did get damaged, replacement was cheap, and
c) the wiring was predictably simple to make determining the pin usage really easy.
I’ve stuck this in #modifications since, although nothing has been “modded” … the terminal info is probably useful for those that want to “play”.
It comes apart easily … 
- 4 screws in the corners of the base - press down on the 4 connectors relative to the top case - everything comes out easily.
- 3 screws on 3 of the corners of the circuit-board
- 2 screws (underneath) that holds the input connector in place.
Inside - after the first 4 screws …
Good news! As expected … just two wires from the input to the circuit-board.
After 3 screws holding circuit-board have been removed.
Input connector removed .
All the parts …
Conclusion about the connector pin usage after checking with a meter …
Pin 1 = data
Pin 2 = -ve
Pin 3 = -ve
Pin 4 = +ve
Pin 5 = +ve
Pin 6 = +ve
Pin 7 = +ve
Pin 8 = -ve
Pin 9 = -ve
Pin 10 = data
Makes sense - seeing the thickness of those wires and the size of the connector pins … spreading the current between 4 pins each way.