Tesla is switching to use the CCS fast DC charging standard in Europe, according to a report by Electrek. The European version of the Model 3 will come with a CCS charging inlet. European Superchargers will get additional CCS charging cables.
Tesla is just now delivering the first Model 3 cars to European Tesla showrooms in the coming week so it’s now forced to talk about the charging connector. The move to adopt CCS raises a series of interesting questions.
What does it all really mean?
Model S and Model X
According to Electrek, the European Model 3 will only come with the European Type 2 version of the CCS inlet as pictured above. At least for now, the Model S and X will continue to be shipped with the Tesla-specific variant of the non-CCS Type 2 connector and all existing Supercharger sites will continue to support Tesla’s original charging cables for use with them.
Tesla reportedly will begin selling a CCS Type 2 adapter that will allow Model S and X vehicles to use European CCS Type 2 chargers. This would allow those models to use any CCS fast charger including the ones from Ionity, Fastned, and other charging providers.
Electrek reports that Tesla will add an additional CCS cable to its Supercharger dispensers in Europe for use by the Model 3.
Both CCS and Tesla use the same physical plug pin to carry signaling messages between the charging equipment and the car in order to negotiate power levels and control the overall charging process.
When it is initially plugged in, the car uses an signaling convention to distinguish whether it is connected to an AC charging station or a DC Supercharger. During AC charging an old simple standard uses a modulated frequency on the “Control Pilot” pin to indicate the available charging current that the car can safely pull.
DC charging requires more communication so Tesla uses a proprietary protocol over this same pin based on an underlying networking technology known as CAN (Controller Area Network). CAN is also commonly used for networking between computer systems within cars such as between components in the powertrain. Tesla then uses a proprietary messaging format on top of CAN to communicate between the car and the Supercharger.
CCS uses the same physical pin but uses it in a completely different way by using a simplified version of the PLC signaling standard originally designed for doing computer networking over power lines. On top of this lower-level networking, CCS uses the same TCP/IP messaging protocols that power modern computer networks.
One possibility is that the new CCS cables added to Supercharger dispensers could, at least initially, continue to use Tesla-style signaling rather than CCS signaling. This might simplify the modifications needed at the Supercharger sites and in the backend computer systems that collect billing information for Supercharger usage.
Why not just keep using the original Supercharger cable and plug it into the top half of the Model 3’s CCS inlet and use Tesla’s CAN signaling? This would allow new Model 3 cars to immediately charge at all existing locations before the CCS upgrades roll out. It may be technically possible.
One reason could be the expense of having to add additional contactors (high-power relays) to electrically disconnect the exposed 2 bottom power pins for safety reasons. Adding CCS cables to a few thousand Supercharger dispensers in Europe would be cheaper in the long run than adding those extra contactors to every future European Tesla car sold that has a CCS inlet.
Could Tesla choose to allow non-Tesla cars to charge at Superchargers using the newly added cables? One catch is that Tesla Superchargers traditionally support a lower peak voltage capability than CCS.
Unless it upgrades the charging voltage limits it could make the newly available CCS-capable Superchargers somewhat incompatible with some of the latest cars from Jaguar, Audi, and Porsche in the future if it chooses to allow those cars to use Tesla’s new CCS Supercharging cables. Those cars could still charge but not all the way until full. This is all speculative, of course.
Tesla Superchargers are currently specified to support charging at up to 410 volts. This works fine for most cars because they typically use 96 groups of cells or less in series to reach a peak voltage of around 400V or less when fully charged.
However, some newer cars use up to 108 groups of cells in series and have a peak fully-charged pack voltage of near 450V. At only 410V they may only be a bit over half full when actively charging on a CCS charger. Both the Jaguar I-PACE and the forthcoming Audi e-tron use 108 cells in series. Recent information about charging in the future Porsche Taycan and Cross Turismo indicate they also may use 104 or more cells in series.
Will the Supercharger hardware be upgraded to support higher voltages? We don’t know yet. Perhaps not until the next major upgrade of Supercharger hardware known as Supercharger 3.0. Tesla has said they will announce the details of the Supercharger 3.0 system later this year or early next year.
Tesla charges at a bit over 350A today on their existing Superchargers. The CCS standards and parts vendors say that CCS connectors need liquid-cooling for sustained charging at over 250A. Will Tesla’s new CCS Supercharger cables be liquid-cooled?
Will the Model 3 be able to charge faster at some non-Supercharger CCS locations? The company’s EPA regulatory filing for the Model 3 says it’s battery pack is capable of charging at up to 525A. Some European CCS chargers that support charging rates at 200 kW or above, such as those being deployed to support the future Porsche Taycan, may be capable of outputting current beyond 350A.
The above charger and dispenser specification from BTC Power shows that it supports output at up to 500A and 200 kW at voltages below 500V. Could the European Model 3 charge faster at such a unit than it could at today’s Superchargers or even at upgraded CCS-capable Superchargers if they initially keep most of their charging power electronics? High power chargers from other vendors can be configured to similarly support 450A to 500A.
Supercharger CCS cable length
CCS-based cars from other automakers locate their charging inlets at various different places on their cars while Tesla has always located its charging inlets at the same place near the rear tail light on the side of the car. Tesla’s Supercharger design today depends upon this and uses thick and heavy conventional cables that are manageable because they are short.
Will the new Supercharger CCS cables be longer in order to enable their use by non-Tesla cars or will the cables be technically compatible but practically unusable by many cars due to cable length limitations?
If the cables are longer will they need to be liquid-cooled? Tesla experimented with some liquid-cooled cables briefly but has never widely deployed them before.
Wither CHAdeMO in Europe?
The CHAdeMO DC charging standard originated in Japan and had been largely adopted by Japanese car companies. Early sales of the Nissan LEAF made CHAdeMO predominant for DC fast charging among non-Tesla cars but sales of CCS cars have been rising and CCS has been quicker to adopt higher-powered charging standards. With Tesla now supporting CCS, the sales volume of new CHAdeMO cars in Europe will shrink to a relatively small fraction.
Hyundai and Kia have already switched to CCS and Honda adopted CCS in the Clarity Electric model in the US. Only Nissan and Mitsubishi presently sell cars in Europe that depend on the CHAdeMO DC charging connector. Which standard will Toyota use when the finally begin selling cars with DC charging in the future — would they really use CHAdeMO at this point? Can Nissan and Mitsubishi keep selling CHAdeMO cars there? How will the DC charging infrastructure for CHAdeMO compete?
What about Supercharging in North America?
It remains to be seen whether or when Tesla could make the move to CCS in the North American market. It’s a more awkward change because Tesla uses a charging connector design in North America that is physically incompatible with the upper portion of the Type 1 CCS connector.
In Europe, Tesla just has to add an extra 2 large DC power pins to the physical charge inlet. For North America it would presumably have to keep the existing inlet for compatibility with existing Tesla charging equipment and add a completely new Type 1 CCS inlet.
Aside from the physical plug design the other changes could carry over from Europe. The European Type 2 CCS connector and the North American Type 1 CCS connector use the same signaling protocols and power specifications.
It’s unclear at this time what Tesla’s plans are for North America.