The first reported slot car track appeared in America in 1912, but it was not until the 1950s that such tracks started to become commercially popular with the launch of Scalextric. Since then, longer and more outrageous circuits have been constructed, most beyond the means of the everyday user. The only issue with longer slot car circuits is power. The standard power packs are only useful on short circuits. You could just buy more power packs, but this will use up a lot of plug sockets and lead to a lot of wiring.
Set up the circuit in the desired formation.
Remove the connecting terminals from the original power pack.
Strip an inch of plastic coating off the 10-gauge wires using the wire cutters and attach the connecting terminals.
Attach the other end of the 10-gauge wires to the battery charger clips.
Set up the connectors under the circuit in the usual way, remembering which is positive and which is negative.
Attach the charger clips to the appropriate terminals on the car battery.