ElectroClassic EV
Classic Cars Reborn into the Electric Future

Ready and Cable

Here is the 2/0 (two-aught) welding cable that will connect the three battery packs together in series. I purchased 30 feet of black Radaflex cable from The Cable Yard, and another 10 feet of red Class K cable from Wire and Cable To Go to connect the motor. Welding cable is the pick of champions for hooking up EV batteries and motors because of its insulation, flexibility, and durability. It’s also designed to handle massive current with little resistance that would generate heat and waste energy. It’s very important to have a pair of cable cutters on hand, because two-aught cable doesn’t just cut itself. Cutters also leave a clean end that can easily slip into the lug, rather than the rough cut left by a reciprocating saw or other means. Folded up in the lower right corner is some large size shrink tubing to cover and protect the lugs after they’re installed.


Lugs are usually crimped onto welding cable because of the superior connection, while soldering requires some expertise to prevent cold joints, heat resistance, or other problems. Crimping is done with a very expensive tool that looks like a bolt cutter, or done less expensively with a swedge tool, shown above. The insulation is removed from the cable end, the lug is slipped over the bare wire bundle, placed in the swedge cradle, and then dealt a few hefty blows with a hammer.


Here is the end result of a swedge crimped lug, ready for heat shrink tubing. These red cables are the pigtails to connect the controller to the motor. Because they’re short and don’t allow much twist, the lugs had to be installed in the proper orientation. That mark on the cable above ensured the lug was at the correct angle before hammering it shut.


Although the rocker panel heating ducts are a good way to run cable from the fuel compartment to the motor bay, I chose to use the center tunnel instead. This results in a cleaner look, and also leaves the original duct openings under the dash clear for other uses, which might include ventilating the charger in the fuel bay. I inserted a cable snake through the large 4 inch hole and into the fuel line port, then fed it down the tunnel and out the hole in the rear firewall. The crimped cable lug was then zip-tied to the snake eyelet, and then pulled through the tunnel to the front, where you see them emerging above.


Here is the cable snake in its coiled state. There must be 100 feet of snake inside this spool. Whoever invented this priceless tool must have been a minor genius. Thank you. The previous owner was in the process of pulling a brake line through the tunnel, and zip-tied the cable snake to the front suspension, where I discovered it after I bought the car. In that sense, it literally was priceless to me.


This view under the passenger side of the front trunk battery rack shows the original stock wiring hole at the far left, and two newly drilled 1 inch holes in the spare tire well. The first hole will house the charging cable as it snakes from the J receptacle under the license plate to the Elcon charger in the fuel bay. The other holes are used to connect the two forward battery bundles to the rear pack and to each other. The newly drilled holes were undercoated, and all three received new rubber grommets to protect the power cables.


This is where the battery cables emerge from the tunnel at the rear firewall, betwixt and between the shift coupling, clutch cable, accelerator cable, main wiring harness, and rear brake lines. I was told on good authority that this hole was not stock, although it certainly came in handy. The squeeze through both front and back holes was tight because the welding cable is thick, forcing the grommets to be installed after the fact. Some silicon spray and a screwdriver finally popped the rear grommet into place after 15 minutes of effort. The hacked front fuel bay grommet took about 40 minutes, some geometric thought, leverage, and sweat. Once the position of the fast semiconductor fuses is decided, the cables will be trimmed to exact length, and lugs will be swedged onto the ends of the cables. Each battery cable will then connect to the opposite end of the motor bay pack, and will be secured to the car to avoid flopping about.


Here’s an exciting preview of the controller on its shelf with cables attached to the three terminals of the AC motor. This was a test fit to determine the exact length of the motor cables for cutting and swedging. The motor terminals are so close that I will probably grind down the lugs to leave more space between them. It was sheer luck that the 3-phase terminals were in the same order on both the controller and motor, so the cables stay parallel rather than criss-cross. The cooling system can be seen yonder, hiding behind the far battery pack.



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