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I returned my Mirai to Toyota at lease end in June, so now I get to borrow my wife's Chevy Bolt when she's not using it, and otherwise bike or Uber around town while pondering what car to get next.

My Delorean (#6673, bought in 1985) had not been driven since 2006, so as a learning experience (never having done an EV conversion) I decided to convert it, starting the project in July. The name is shamelessly stolen from Jeff Cooke's TesLorean but with a Gen1 (2012) Chevy Volt battery and Elaphe M700 in-wheel motors in place of Jeff's Tesla-based setup. This arrangement allows the back 3 modules (66s3p) of the Volt's battery to fit neatly in the vacated engine bay without needing to modify their T shape. The front module (30s3p) will sit in the vacated gas tank bay. I'm hoping to get between 50 and 80 miles of range this way.

The battery separation will be by undoing the electrical and cooling connections at the big slot between the front two modules and sawing through the cover and metal base. Once the electrical and cooling connections at each side of the cut are brought out I'll bolt the two halves of the cover back on to their respective battery halves and reconnect the electrical and cooling connections so as to restore the original functionality of the battery.

Current status: body is off the frame, gas tank, engine, transaxle, and uprights are out (so the trailing arms and links are flopping around) and no longer needed, rear is sitting on a furniture dolly (with no motors, inverters, battery, or rear suspension the car's weight at the rear is a mere 134 lbs!) making it easy to wheel the frame around the garage and driveway. Battery is sitting next to the frame for now, cover is off but uncut as yet. It is partially charged to 345 volts, with all four modules' voltages within 0.05% of each other after dividing by the number of 3p cells in each module (30 in the front module, 24,24,18 in the rear three). (I'm guessing they're so close because their four LG Chem BMS's, one on each module, have been doing their thing all the time the battery was sitting in the wrecking yard, does this seem plausible? The other explanation might be that LG Chem makes very reliable batteries.)

For the time being I'll be trickle-charging the battery up to 360 volts or more using some series-connected subset of the eleven 48V 0.38A Cisco adaptors that I found on eBay for $39 for the lot (so $3.50 apiece); will improve this to more than a trickle once the car is running and registered. This may require a better understanding of the dozen or more connectors (mainly data?) at the front of the battery besides the two 360 volt high-current ones.

Apropos of all this I have a request for people who've been buying and tearing down Gen1 Chevy Volt batteries for their individual modules. There is a complicated connector pair between the front two modules that I imagine serves no purpose when those modules are no longer being used together. It occurs to me that the easiest way to make a six-foot cable to connect those two modules back together after they've been moved to opposite ends of the car would be to get a discarded connector pair from another battery and run the dozen or so wires between them needed to turn them into a cable. Anyone know anyone who might have such an unused pair of Gen1 connectors they'd be happy to sell me? The alternative being to ask GM if they can sell me a pair of connectors, though it's not like the sort of thing you'd find in the parts department of a Chevy dealer.

Thermal management of the Volt's battery is discussed at https://gm-volt.com/2009/01/05/chevy-volt-battery-temperature-control/ which aims for the neighborhood of 71 °F. The inverters, motors, and cabin all need their own thermal management too, so this is going to be one of the interesting challenges for this project. My current thinking is to use the Delorean's radiator and two electric fans to cool the inverters and motors since they can run relatively hot and to have one electrically driven A/C compressor servicing both the battery and the cabin, with the refrigerant passing through the cabin's evaporator but also through a heat exchanger to cool the battery's coolant (presumably Dex-Cool) kept separate from the coolant for the inverters and motors. In winter, heating the cabin and battery while driving can be done with the coolant from the motors, but a cold start may need the battery to be pre-heated using an external power source (same one used to charge the battery).

Since the battery is only one foot tall there will be loads of space above it. The Delorean could make a nifty pickup.
 
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