Latitude c640 battery pinout

ugh, best of luck finding that...

If I may ask, why do you wish to have one?

Left to right looking at connector:

1 Neg
2,3 NC
4 Switch (short to neg to enable battery)
5 NC
6 Data
7 Clock
8 NC
9 Pos

Note that some of the NC pins should be connected to the thermistor, but these are the connections that you would need to charge or communicate with the battery.

To be sure of your orientation, use a volt meter to find pos and neg before making any connections.

This pin out covers around 75% of all Dell laptops