DC Quick Charge vs Supercharge

Tesla has indicated that they will be able to provide an adapter to charge from any format including DC Quick Charge station, Mennekes, Chademo etc.

 

The level 2 stuff (e.g., 240V@~16 - 70A) tends to use a standard signalling method between the charging station and the charger in the car. So, for instance, the J1772 adapter that Tesla provides for Model S (or Roadster) to connect to public J1772 charging stations is just a physical pin to pin mechanical adapter so that the two can plug together.

DC "fast-charging" (or "quick-charging") isn't as simple. We know, at a minimum, that Tesla uses a different signalling method for the Model S to talk to the offboard charging equipment in their Supercharger. There will probably need to be some little "translation computer" in the adapter to go from something like Model S charge port to a CHAdeMO DC quick charger (like the Nissan LEAF uses.) I suspect that adapters for Model S to use a non-Tesla quick-charger will be quite a bit bigger and more expensive than their simple Level 2 J1772 adapter.

Tesla mentions that their Model S will use SuperChargers up to 90kW. Nissan LEAF CHAdeMO chargers are typically 50kW or less.
So, another difference is that Tesla's supercharger will offer slightly faster charging possibility that some of the alternatives.

But, at the end of the day, the Supercharger is "just another offboard DC charging system", so in that way it is similar to other DC quick chargers that have CHAdeMO or SAE combo plugs on them.

It is yet to be seen how the industry works out compatibility between systems. Will someone build a multi-charger with different plug types to suit different vehicles? Will Tesla build an adapter for Model S to use a CHAdeMO charger? Will someone build an adapter so a LEAF can charge at a Tesla supercharger? Plenty of unanswered questions here.

 

Which asks the question, who will be responsible for the Leaf's batteries' short life if charged too fast, too hot? Does the adapter tell the supercharger to slow down because you only have 24 kW of batteries here instead of 85? Does the adapter maker pay for new battery packs on Leafs? Do fires start? Plenty of unanswered (and unasked) questions here.

 

The car has to communicate to the charger what the appropriate amps and volts are for charging its battery. Anything else would be crazy.

 

Which begs another question, will Tesla allow another entity to have usage rights to their proprietary charging network? If I'm Elon, do I want Volts and Leafs charging at Tesla supercharger stations and possibly block Roadster or Model S drivers? Yes it would be helpful for all EV drivers to have access to all available EVSE's but would the people at Tesla feel that Nissan and GM were parasitically taking the investment Tesla made for their customers? Hmm...

 

Unless someone offers a Tesla to J1772 adapter, they will not be using the level 2 chargers, and the Superchargers will be of no use to them at all. I have no problem letting leafs charge at Tesla charging stations, as long as Nissan dealers let Model S's charge at their chargers. All of us EV'ers are in this together, and there are not enough chargers out there to not share.

 

They could just put some J1772 stations at the SuperCharger spots. Perhaps charge a small fee (vs free for Tesla owners) to recoup the cost.

 

Anybody have an update on plans for a chademo adapter for the S? Just 'we're working on it', or is there more?

Sorry if that discussion is actively going on in another thread right now--haven't found anything recent in a while...

 

Thread is here.

 

The Nissan to Tesla connection wouldn't be J1772, that's AC and is pretty much a dumb connection.
It would have to be CHAdeMO to Tesla, which is DC and would require a software and hardware protocol translator. CHAdeMO is an open system as it's being publicly installed at government expense, so Tesla could build a CHAdeMO to Tesla adapter and expect it to work.
Superchargers are proprietary, there are no government installed ones, so it's not clear that a Nissan supplied Tesla to CHAdeMO would be allowed by Tesla software.
As I've said before, I expect that both CHAdeMO and Tesla DC charging will be superseded by the SAE standard, at least at public stations which will likely be the most common.

 

thanks very much jerry33.

 

During the shareholder's call (?), when the SAE standard was pointed out to Elon, he said "Yes, the SAE have a standard. But it sucks." Which is why TM went its own way. I rather doubt it will "supersede" TM's standard anywhere except, as you say, the public stations -- which will "suck" compared to TM SuperCharging.