Does anyone know the reason for 625.13 requiring vehicle charging equipment to be permanently connected ... as opposed to being plugged in with a suitably rated plug?

They put a loophole in there to allow 240v chargers like this. It just needs to be listed.
http://www.leviton.com/OA_HTML/ibeCCtpSctDspRte.jsp?section=41916&minisite=10026

I guess that works as long as they list it for cord and plug connection. If/when I go with one of these electric cars, I might have as many as 4 locations I'd want to charge up from, and don't want to have to buy a duplicate charge station at each (unless they get lower in price).

I suppose I'd have to fit a plug on the end of the cord they provide since I've not seen the specs listing a particular plug type. If they did, I wonder what type it would be. The NEMA standard L6-50 is only sold in Japan that I can find. American companies seem to only have the non-NEMA "California" types. Or there is the IEC-60309 360P6W.

Poking around on the Leviton site I see a EVB22-3PM that is 3.8 KW and uses a 6-20P. (16a) so there are different models.
I think I would look for one that was 30a and I would put a "dryer" plug on it. The garage is usually where the dryer is around here. I put a dryer plug on my welder 40 years ago and that has saved me a lot of times because most people have a receptacle. I have a 25' extension cord with #10 and a 50' with #6 SO cord (yanked out of a computer room)

I'm aiming for at least 7.2kw charging rate, or higher. Supposedly all but the smallest electric cars can do that. I haven't made any purchasing decisions, yet. But I'm just thinking of options.

One of the things that will hurt electric cars is that they just can't do the "quick fill up" thing that liquid fuel vehicles can do. That's going to make it very difficult to adopt electric cars for anything but local usage. But these slow level one chargers (120 volt 15-20 amps) aren't really going to help much unless you get the miniature cars.

FYI, a friend of mine is building his own electric car on an old frame with new motors and batteries. He plans to just use it for show and grocery runs, and charge it totally from solar and wind. It will be interesting how he sets this up.

Was just looking at some details on the Nissan Leaf. Its 120V charging rate is 5 MPH (e.g. an hour of charge adds 5 miles to the range). Seems like a convenient way to measure charging rates.

I could not find that charger with the 7.7KW output on the web site. I am not sure if they still have some bugs they are working out or if this just hasn't made the web site.
The Focus has a 23kwh battery and theoretically a 7.7 kw charger would bring it up in 3 hours. That isn't horrible but you need to find 40-50a at 240v. If I wanted to really be "portable" I think I would make up some adapter cables for a bunch of different receptacles and pack a long power cord.

I'd just put in a 240V 50A outlet at each location ... cheaper than putting in a hardwired charging station. But it remains to be seen how hard it is to deal with hauling the charging station around. Still, I'd rather have the charging station be plugged in to an outlet rather than hard wired. And I'd rather have a L6-30 over 14-30 anyway, if I was going to do this at the 24A level. Above that, L6-50 is hard to find (import from Japan) and IEC is more expensive (heavier duty, too).

FYI, I've read that a gasoline pump delivers energy at a rate approximately equivalent to 5 megawatt. I don't think any all-electric car is going to reach that any time soon. It's not just the short range (which I'm sure they will gradually extend), but the time waiting for the rapid charge to complete during the trip. Gonna have to be restaurants and motels combined with charging stations.

You could go with a 10-50 "range" plug.

Why a 10-50? Why not a 6-50 or even a 14-50? I kind like having an officially designated EGC. Yeah, I know a 10-50's neutral could electrically act as an EGC on a dedicated circuit (which this most certainly would be).

I'd rather have a locking connector, but a straight blade will do. I also want some kind of cutoff switch before the outlet. One of those 60A motor switches would satisfy me, but maybe a small 2 slot breaker panel with a 50A GFCI would be good.

Some cars have their inlet on the front and some cars hav their inlet on the side (where one might expect fuel input to be).

6-50 is probably a more proper choice but the 10-50 is more prevalent. The retention force on those plugs is high enough that they won't be falling out.
If you really want something secure the IEC 309 67 series is good but they tend to be pricy. We started using the 309s in the computer biz when Russell Stoll fell out of favor.

That's one reason I'd have rather used a L6-50. The L6-30's at work (each computer cabinet is fed by L6-30R hanging from conduit+box and UPS's built-in 8 foot cord and L6-30P reaching up to connect) were easier to plug in and unplug than my 14-30 on the dryer at home. So I suspect a L6-50 would be easier than a 6-50. Yeah, those straight-blade connections won't fall out without a lot of force from somewhere.

The 309's do have the advantage of a shroud.

I looked at the twist locks and the Hubbell CS8269/CS8265C says it is 2 pole 3 wire but it looks like it can do 4 wire too using the connector shell.

http://www.hubbellcatalog.com/wiring/catalogpages/section-b.pdf

page B-32 & 33

Have you looked at the 'Meltrics' line of receptacles and caps? Pin & sleeve design, thermoplastic bodies, and some are rated as disconnects and satisfy LOTO requirements.

www.meltric.com is the website.

They sent me a sample setup a while back for 'show & tell' at a CEU meeting. I have no idea of $$$ (edit)

Those do have designated pins ... ground, neutral, and hot in the 125V version, and ground, hot, hot in the 250V version. The 125/250V version on another page does designate the shell as ground.

I have seen those before. I recall seeing their high ampacity version somewhere in person. I would bet they are pricey.

That Hubbell does look like it should work for you without going to Japan.

I guess I should not hold any real preference for NEMA plug configurations. Of all the designs they have for many voltage, system, and amperage configurations, there's only one pairing that is compatible between 120/240 and 240 volt systems, and that's 6-15 vs. 14-15 (e.g. a 6-15P will plug into a 14-15R). Maybe I'll write more some day on how a smart system could have been designed.