I know this is an older post, but the I-Cybie battery has five cells on each side of the center wire, if I remember correctly. It was essentially to make a split supply to cut down the need for drive transistor for all the motors.
Just checked on one I had in another robot, reads 6.5 volts yellow to red, 6.39 black to yellow, seems to bear that out.
ASCII art :
___+---+___
| o | o | o | viewing the pins end on the battery
R Y B