As DC fast chargers multiply, so do standards

Public DC fast-charging stations are proliferating around the world at what some might call an alarming rate. In at least 50 countries, EV drivers can top up their batteries in the time it takes to (leisurely) enjoy a cup of tea, or whatever the local beverage may be.

While automakers agree on the importance of fast charging, they have not united behind a single technical standard, nor are they likely to do so any time soon. There are currently at least three DC charging standards in operation in the US, and which one you can use depends on which model of EV you drive (for AC Level 1 and Level 2 charging, all current EVs conform to the same J1772 standard).

Industry trend-setter Tesla has its own Supercharger standard, which is now available at 209 sites in North America, Europe and Asia (it’s not clear how many individual charging stations this represents – for example, Tesla’s 200th installation, in Oxnard, California, has 10). For the moment, only Tesla’s Model S can use the Supercharger, although Elon Musk has said the company is open to making it compatible with other makes. Tesla says that an adapter that will make Model S compatible with CHAdeMO is coming soon.

SONY DSC

The newest standard, CCS, which combines both Level 2 and DC charging on the same plug, is supported by the American and German automakers. Cars that use it include the Chevy Spark EV, BMW i3, and VW e-Golf. There are some 435 CCS charge points in Europe (according to a nifty interactive map by a gentleman called Mutwin Kraus), but only a handful in the US so far. However, that may change soon. BMW has a deal with NRG to install up to 100 in California by the end of the year, and when VW starts selling its e-Golf stateside, it’s likely to make a push for more CCS stations.

SONY DSC

In terms of sheer numbers, the CHAdeMO standard, championed by the Japanese automakers, has already won the day. There are 4,241 CHAdeMO chargers in the world, including at least one on every inhabited continent. “CHarge de MOve” is used by the industry-leading Nissan LEAF, as well as the Mitsubishi i-MiEV and the new Kia Soul EV. For a while, some in the EV media were speculating that the European standards agency was going to refuse to recognize CHAdeMO, setting off a destructive standards war, but cooler heads seem to have prevailed, and CHAdeMO and CCS are co-existing peacefully for now. Some charger manufacturers have wisely sidestepped the issue by producing dual-standard chargers.

GBT-Standard

It’s anyone’s guess what’s going on in China. Theoretically, there is a national standard called GB, but it’s still subject to disagreement among Chinese officials. “Until about 2016 China won’t have a DC standard formalized,” says David Reeck, the former Manager of Electrification Strategy for GM China. SAE is now working with China’s CATARC on a DC standard, and a group of foreign automakers known as the Charging Interface Initiative Asia has been encouraging China to adopt a combined plug standard similar to CCS.

 

Source: Tesla, CHAdeMO, Alysha Webb’s ChinaEV Blog, InsideEVs
Image: Top – BostonTx/Flickr, 

  • http://twitter.com/brian_henderson Brian_Henderson

    This article omitted (ignored) the official European Type2 Standard Connector that supports both AC, DC, and Supercharging. The Type2 supports charging at up to 500V (both AC & DC), handle 200A and has the advantage of being a more ergonomic design compared to other DC connectors.

    An additional advantage of Type2 connector is it’s fully compatible with J1772 plugs by using a connection cord with J1772 at one end and a Type2 at the other end. This offers low cost access to charging points of both AC standards. Outside of Tesla’s CHAdeMO adaptor (in testing, but not yet released) there are no other adaptors available that support connecting between standards. (Nissan includes this type of cord with LEAFs delivered in Europe).

    Type2 Standard supported charging configurations.
    http://insideevs.com/wp-content/uploads/2013/08/3.png

    Type2 on Tesla Model S which also supports Supercharging in Europe
    http://insideevs.com/wp-content/uploads/2013/08/125.jpg

    Size comparison between Type2 and CCS plugs (CCS & CHAdeMO) are similarly oversized needing two hands to connect.
    http://www.plugincars.com/sites/default/files/combo-and-mennekes-plug.jpg

    The large CCS and CHAdeMO connector are more costly to manufacture and due to poor ergonomics will be dropped more by users. The issue less about the connector breaking, but picking up dirt and contaminants that will effect the quality of the electrical connection. A significant number CHAdeMO connectors fail in field related to improper handling of the oversized awkward connectors.

    What would it take for CCS and CHAdeMO standards committees adopt the Type2 connector and support their communication protocols like Tesla accomplished with providing Supercharging access? If standards committees could leave their egos at the plug, we’d have a universal connector that could support all charging protocol standards.

    • vike

      You wrote that Type 2 supports DC fast charging at 200A, but the diagram you included shows that is only provided with Type 2 CCS (the bottom picture for “DC-High”). The basic Type 2 connector itself only goes to 500V DC, 140A if I’m reading that chart right. Could you clarify/explain this?

      • http://twitter.com/brian_henderson Brian_Henderson

        Tesla uses the same pin configuration as DC-Mid configuration, but with superior materials to support 200A. The Type2 is able to supply 80kW at 400V & 200A.

        If a Tesla EV (Model S) connects to a ‘standard’ public infrastructure, then the ‘standard’ protocol will be followed, only requesting the max. ‘standard’ amps. (140A max., about 55 kW for a Model S’s 400V pack)

        This was part of my point; by using better quality materials the extra 2-pins associated with combo connection are not required.

        Benefits are reduced connector size and weight, plug a plug that can be more universally adopted. Reduces the need to have both an AC Type2 connection and a dedicated DC Type2 CCS combo connection … a singe Type2 connector can supply both AC & DC charging.

        Further the CHAdeMO protocol (signaling) could modified to support charging using the Type2 connector. Some engineering would be needed to convert the analog

  • cw

    They need to get one standard for DC fast charging or adaptors….. they did it with the 240v! it makes the EV in general look bad to newcomers when they figure out there are all these different standards going on…… I personally expect better from the EV industry, and I own an EV.

    • Lance Pickup

      I’m pretty sure that was intentional…the consortium responsible for CCS (and unlike some others, I don’t have a problem per se with the CCS connector) likely did not adopt the existing CHAdeMO standard because they were behind and thought they would throw a little confusion into the mix to slow down the deployment and allow them to catch up (and to some extent, they were successful).
      The good news is that at the end of the day the DC charger is essentially about providing a communication path between the charging station and the vehicle. The vehicle specifies how much voltage & current it wants and the charging station complies and sends the requested power through its DC terminals. So there is very little impediment to chargers that can speak multiple “languages” or adapters that can translate. And in fact this has been done in the case of dual-headed CHAdeMO/CCS charging stations, and the forthcoming Tesla CHAdeMO converter.
      Now there is the other concern of the Supercharger network being proprietary, so Tesla can simply decide it doesn’t want to allow “foreign” vehicles to charge on those chargers. This is not Tesla’s intent per se (they are willing to open it up), but they want to ensure that before they do that the other vehicles are able to accept enough power that they won’t be tying up a charging spot longer than necessary because they are not taking full advantage of the Supercharger’s max charging rate. I can see both sides of the argument here, but in the end it boils down to the fact that they could solve this through the use of time-based fees rather than a simple go/no-go policy.

      • vike

        That’s a pretty fair assessment of CCS vs CHAdeMO. There’s nothing intrinsically horrible about CCS, but it’s created an unnecessary mess. Since I don’t think either represents the end game for fast-charging, I hope we can just live with the “okay, so there’ll be two standards for Level 3 in the U.S. and Europe” (as I expect the Japanese will ignore CCS for JDM), understand that this technology is in transition, and just take this as a lesson learned and do better when it comes to whatever “Level 4” might be.

        Speaking of which, I’mnot sure I understand what you’re saying about Tesla Superchargers. The problems you note (non-Teslas tying up Superchargers with their puny soda straw charging capacity) cannot be addressed by time-based fees. Superchargers aren’t set up for billing at all, since access to the system is accounted for in the purchase price of Tesla cars. If other manufacturers want to play, I imagine they’ll have to pony up for Supercharger construction costs to buy similar benefits for their customers.

        • Lance Pickup

          Correct, Superchargers are not set up for billing today. I was speaking in the hypothetical. If/when other manufacturers take Tesla up on their offer to open up Superchargers to other vehicles, they will have to work out some kind of revenue plan where money flows in the direction of Tesla. Tesla could just demand a flat fee from other manufacturers to allow their vehicles access to the network, but I suspect that the only fair arrangement would be to weight the fees based on actual (or at least approximate) usage by the other brands’ vehicles, so some kind of accounting mechanism would have to be added (and I have no doubt that that’s well within the technical capabilities of the folks at Tesla Motors if it’s not already present). to tally usage figures for each different brand (and possibly direct bill non-Tesla customers if that’s the direction they want to go).