At 60v it gets that low? Dang those 6v batteries. Well, they also last a long time. If you want to test out a controller too, it's going to look pretty funny at 144v. You'd be riding dirty... It could ruin your reputation, though. I just visited
punishmentcar.com. That is awesome!
By the way, I am going to order a copper heat spreader. A big dang brick! Copper has almost 2 times the thermal conductivity of copper! So, heat will be sucked away from the mosfets 2 times better! Aluminum is better at releasing the heat to the air, so the copper will be attached to Ben's heat sink, which will efficiently vent the heat from the heat spreader.
On the EVTech list people were paying around with the idea of water cooling. It didn't sound that hard, and it wouldn't be very expensive! You drill a big hole all the way through the copper, and run water through it with a small pump. That could allow for 1000 amp currents I bet! Those mosfets would be kept chilled! There's like nothing in the world with a higher specific heat than water!
I don't really know anything about radiators, or how this would all work, like where the water reservoir would go, etc... It would be a fun feature that could be added later, if people get really greedy for more power.