Ah, picked up the terminology from Wiki. Here's the link you were too lazy to put in. The Volt just uses the normal cycle, but is highly optimized in other ways (variable cam timing separately for intake and exhaust, super high compression ratio, advanced generator with variable torque/speed/output electronically controlled) so it does a more than decent job - the thing gets better mileage on this engine, without the turbo, than the Cruze which weighs less due to that. I'll vote for the simpler engine myself - if I'm going to have weird linkages, I'd rather have them in the lower torque parts (cam drive).
I found the paper that describes the SAE standard for chargers. Well, charger is a misnomer - glorified extension cord is more to the point, there's very little in one of those, they could be made FAR cheaper than the $400-800 they are getting for them. If I can get one of the connector vendors on Alibaba to ship me a few, I'll start making them, one heck of a lot better and cheaper than the manufacturers do. I note on http://gm-volt.com/forum/index.php that a lot of the people who own these, like me, are running on solar PV systems and using them to charge their Volts.
Well, then - I'm no longer such a weirdo, or at least I have a lot of company at it. I'm using the Volt as a diversion load, as all my charge controllers have fried - at present all I have is this big knife switch to take the panels offline, not so great, and I'll be making something better soon, but till then it seems nicer to switch in the Volt than to switch out the panels. There's just one thing - the supplied GEC (glorified...) only has two draw settings, and in fact the standard says this is infinitely variable and in real time. Would it not be much nicer to have it adjust the charge current to maintain the battery voltage, when possible? Further, my 120v inverter can go a lot more amps than their max at the moment - they limited it to what a standard NEMA 120v outlet can do, and in the case of GM's thing - only use 16 ga wire, yuck.
The paper implies that I could use something like a PIC uP to generate the signals required to talk to the car. Looks darned easy - pics even have built in programmable PWM outputs which is how you talk to the thing. So a pic and a quad opamp, and if I go the safe route, a big relay - that's pretty much all that's needed other than a +/-15v power supply for the opamp to make the +/- 12v signals required for this (and 5v for the pic). If I should use the same board we use in the std counter - I'm almost done before I begin, and I get USB on top, so my home computer network can get involved to set settings (or use the RS232, whatever I feel like, and I could easily enable both). This would let me do charging at whatever current I want to hold the house batteries at whatever voltage I want to hold them at - at least until the Volt itself is charged and stops drawing current, which doesn't look like an end-of-the-world hard to solve problem.
So I guess I have a PIC project to do, a little fun one. The built in a/d can handle all the sensing with a feed from my house batteries to monitor those. It could send a signal to pull the panel switch too once the car is up to charge.
One thing I found out last night is that the Volt will draw power from its batteries when it gets cold enough outside (we had 20 F last night). So it wouldn't mind staying plugged in most of the time to make up for that. Also, if you remote start it with the climate control turned on, it will use house power to warm (or cool) the cabin for you so as not to use its battery up before you leave. A nice feature around here - I'm rarely in a super-rush to bolt out the door and go, I usually have a bit of warning, and getting into an already warm car is kind of nice. This will do that with a lot less energy waste than idling an IC engine as it stops drawing power when it gets to temperature.
Now to try and sucker some guy in China into sending me sample quantities of those fancy connectors. They usually only like to sell a shipping container of junk per (the type you can live in).
But we'll see - they can't be selling that many as there just aren't that many of these cars out there yet, they might be workable with.