Batteries:
48V 20Ah of duct-tape lithium
Controller:
Slightly modded stock controller. 40A.
Conversion time and cost:
Current worth at about $1,300. Way, WAY too much time spent on the battery box.
Method for 12v system:
Uh...there's a tap three cells deep into the pack for the power relay's coil.
Typical range:
30mi minimum, theoretically around 60 if I help the motor.
Watt-hours per mile:
27 with heavy throttle, no pedalling.