The various standards bodies have determined two levels for the J1772 electric car power supply, which has resulted in no standard for charge rates above that. Thus implicitly, Level 3 charging means anything above 19.2KW. There have been three L3 standards to emerge.
These are all loosely speaking "Fast DC" chargers but that oversimplifies what's going on. The car and charger need to collaborate cooling, current levels and more. The J1772 connector was really only designed for 10KW. So something else needed to be done.
The three conventions are TEPCO's CHAdeMO, the J1772 "Combo" connector (aka CCS), and Tesla. Functionally, they are all relatively similar, but they are significantly incompatible.
CCS responds to the weakness of the J1772 connector by adding an adjacent pair of high capacity conductors to the standard J1772 interface. Much of the J1772 protocol can be retained, and a regular J1772 plug can be connected to a CCS capable car, and it will simply charge at a Level 2 rate. It's a kludge, but it's compatible. Several European standards agencies are pushing for its adoption, so while there are not presently many installations, there likely will be soon.
CHAdeMO has much better market penetration. There are a bunch of chargers all over. Most of these are on one of the commercial charger networks, although surprisingly many of them are free. Nissan and several others are compatible, and others, including Tesla, sell an adapter.
The most interesting approach, I think, is Teslas. They use the same wires as J1772, but they made sure the wiring in the connector and the car itself are much beefier. Thus the exact same socket can serve both functions. By being electrically compatible but mechanically incompatible, they can hijack the J1772 wiring for L3 charging.
Most commercial charging sites have some billing system. Blink and ChargePoint are two that are popular here in the northwest...both have L2 J1772 and L3 CHAdeMO stations. But Tesla has gone a different way. Included in the price of the 85, 85D and P85D is free "supercharging" for life, and you can buy this feature for $2.5K for the 60. Unless you do a tremendous amount of long distance commuting, this is not too cost effective. But the high price is helping Tesla afford to build out the network of superchargers. As of this writing, Tesla has 403 stations around the world, almost half in the US. Many major routes are supported, but there are still a great many gaps, and for the time being, they have not built many close to cities, figuring that home charging will serve most of that need. (But that leaves gaps. For example, if all you have is L1 charging at "home" (e.g. a hotel or billet) but you have more than 70 miles a day of errands to run)
Last summer, in the leadup to the announcement of the BMW i8 and i3, Elon Musk widely dropped the hint that he was negotiating with BMW for them to be compatible with the Tesla supercharger. This would have been a terrific deal for both sides: BMW would get a widely installed base of fast chargers, and Tesla would have a partner for the very expensive and time consuming buildout of their network. For the time being, Tesla is being very generous with their installations, basically funding it from the high prices they can charge early adopters. But BMW made it clear that they would not participate in this and now that the i8 is available, it uses the CCS "Combo" connector. It's unclear whether this was because of pressure from EU politicos or what.
Tesla presently charges once for lifetime supercharger use, but there's no particular reason they need to. All the existing cars will continue to get free charging, but eventually they'll go away. If they want to bill, either by KW or by the month or something, it's easy to do. The car can identify itself to the charger and send a bill to the appropriate customer. This could easily be implemented over the "proximity" conductor, or even by some sort of RFID. This is exactly what the existing services, including Blink and ChargePoint, do. If Tesla is clever about it, they can sell a fast charging adapter that includes a supercharger license and allows you to plug your CCS or CHAdeMO vehicle into the supercharger. I can even imagine supercharger stations offering single use rentals of these gizmos.
If one of the other plug formats ends up winning, Tesla has a simple solution. They already have a CHAdeMO adapter, and they've said that once more than a handful of CCS stations are on line, they'll develop an adapter for those too. The stations themselves can be gradually converted over as demand moves. Most of the cost of these stations is in the real estate and preparation, including the wiring, which is the same for all. The charger and connector is probably less than 10%, and I bet even most of that can be switched over easily. Although if this happens, I suspect most Tesla stations will be sold to some other franchisor.
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