Competing Electric Car Charging Standards Can Be Easily Fixed

In every industry that requires connection or interoperation, there are standards battles, so of course electric car charging has one. In the USA, there are two main connectors for slower Level 2 charging (Tesla and J1772) and three connectors for fast Level 3 charging (The same Tesla, Japanese CHAdeMo and an expansion of J1772 called CCS from non-Japanese automakers.) The reasons for all these connectors involve a complex history which I will outline below, but first I want to write about how we can get to what all drivers, and most charging station operators want, which is for every car to be able to charge everywhere.

One answer to that would be a common standard, but that didn’t happen and many of the reasons it didn’t happen are valid in a constantly changing and innovating field. The other answer is adapters.

No adapters between CCS and Chademo (as it is more commonly written these days) exist. An adapter to let a CCS car from Chademo is the easier of the two to build, but instead, almost all new charging stations are just installing both CCS and Chademo plugs on them to serve both cars.

An adapter to charge a Tesla from Chademo is sold for $450. This is the easier adapter to make, though in Europe older Tesla cars can get a CCS adapter for €500. Chademo is easier because it uses the same data protocol and manges locking in its own plug.

There are no adapters to let other cars charge at superchargers. While they could be technically possible, Tesla built its supercharger networks out big and quickly at great cost so that Teslas would be the only cars able to take practical road trips — and it works, and contributes to Tesla’s sales. They even provided supercharging for free to Tesla cars for many years. While they could decide to offer their chargers at a profitable price to other cars, for now they like being the only car with a dense, very high speed charging network. Elon Musk has said they don’t need to be a walled garden, but the other manufacturers would need to pony up some of the cost of having built the network.

Tesla has taken an odd path, though, with their Chademo to Tesla adapter. Their supercharger network is so good that one should rarely need it. Almost every Chademo station has a supercharger not too far away. However, there are a selection of places (California highway 99 is a big example) where that’s not true. If Tesla owners can charge at Chademo stations there (and a few other places) it’s good for the operators of those charging stations, but very good for Tesla owners, and Tesla itself.

To my mind, the obvious strategy for Tesla should have been to offer the adapters, at cost or even free, to the Chademo charging operators, not to the car owners. There are perhaps only a few hundred such Chademo stations. The adapter could be provided in a protective box with a retracting locking cable on it.

1. For the station owner, it’s a big win because Teslas are by far the most popular electric cars that might come by their stations.
2. For Tesla owners, it’s a big win because now they can do road trips in places they can’t otherwise go, even if the charging is slower and a bit more expensive.
3. For Tesla, it’s a big win because their cars become more useful, and Tesla gets that at a tiny, tiny fraction of the cost of installing their own supercharger in this more marginal locations. Tesla should actually list these stations in their charging maps and charge planning navigator.
4. For owners of Nissan Leafs and some other cars, it’s a loss, because the Chademo stations would become much more heavily used due to all the Teslas.

In fact, a few Chademo stations have actually purchased these adapters to loan out to Tesla drivers. As yet, there is no way to get those to display easily on your favorite charging map.

An alternate approach would be for Tesla to rent these adapters at a break-even price to Tesla owners going on road trips. This doesn’t require agreement with the charging stations but does the job, though it needs a lot more adapters as there are vastly more cars than stations where you would want to use them. In my own experience, I would ever have used one 3 times in a year of driving with 3 road trips. There is a company which rents them for about $40/week.

Even so, none of these things have happened, and they may not, because more than the simple desire of drivers and stations to make charging happen is pushing decisions in this area. There are also egos and pride, which comes from the history.

Update: Just hours after releasing this story, charging network operator EVgo announced it would be placing Tesla adapters at some of its Chademo stations. The first 5 are in San Francisco (not very useful because there are superchargers there) but in time they will presumably spread out to more isolated stations.

Designing for a world of competing standards

People who try to design interfaces like EV plugs all presume that their standard, or at least some standard, will win. Sometimes that happens but sometimes it doesn’t. It would be better for the world if such designs presumed they might not win, and instead made it easier for multiple standards, and adapters, to exist. A key way to do that is to make sure data communications can always be done, and that power exists to power processors which do such communications or which do interfaces. Chademo provided that power, CCS did not.

Of course, you want the digital protocol to communicate what voltages and currents are to be used, and to understand if they can be made compatible. While cars can’t change the DC voltage they take, that remains up to charging stations to handle. They can be upgraded as new cars come along since they are already converting the power to the output voltage.

Another key factor is how locking is done. You can lock in the car (As Tesla and CCS do) or in the connector. One way to be future-proof is to put in the holes for locking pins on both (which is cheap) and only put the pin in the place you like. Adapters can then do it both ways.

The history of EV charging

The conflict has come over high speed “Level 3” charging, known as “DC Fast” or “Supercharging” in Tesla’s case. In addition to the Tesla system, as I described above, there is the Japanese system CHAdeMo and the Euro/US system known as CCS. People lament that there are 3 systems, since it’s a common mantra that “standards” are of primary importance. Standards are valuable — and both Chademo and CCS are multi-company standards which compete — but they also often mean an impediment to innovation, which is bad when an industry is nascent and growing. Sometimes standards have allowed a stagnant industry to take off (VHS, the compact cassette, CDs and DVDs are an example) but sometimes they have stood in the way. In the computer industry we tell a joke that “the great thing about standards is that there are so many to choose from.” Standards are more often useful when it comes to hardware, where things have to plug into things, and less useful in software, which can be adapted and changed in the field in real time.

The 3 plugs in cars derive from history. Everybody knew that to make electric cars practical, they needed to charge much more quickly. At least, that’s what people thought when batteries were small, and cars could go only 80 miles in a day. Over time, we’ve learned that the big reason for fast charging is to allow very long trips, like highway road trips — slow charging every night at home actually works just fine for the new generation of cars with bigger batteries. It’s also useful for fleets and trucks.

In Japan, they developed Chademo. It could charge at about 50kw, compared to the 3-6kw typical for slow Level 2. That’s much faster, and fine for a small battery car, but a bit slow for the new cars. Chademo uses a very large plug, and it’s a completely different plug from the Level 2 plug (J1772.) Cars that use it need to have two sockets.

Tesla had already built their own Level 2 plug for their Model S, and it’s smaller and more capable than J1772. Tesla correctly presumed since everybody else made their EVs just to comply with legal quotas, that theirs was the “real” car and it would outsell them. It had no reason to comply with the standard, because it would make more cars than all the others put together, and their plug was better.

One way it was much, much better is that Tesla’s same interface handles both the Level 2 charging and the Level 3 supercharging in the same much smaller plug. Tesla felt it selly to put both the lesser standard and their own superior plug on the car when there were so few “standard” stations a Tesla might want to plug into. While Chademo existed at the time, it had very little deployment, and again, Tesla’s plug was superior in every way. In particular, it could do 120kw instead of 50kw, and today that same plug does 250kw.

Chademo got a boost though when the Nissan Leaf became the first car from a big OEM that wasn’t just made to make quotas. Nissan sold a lot of Leafs and it was in the Japanese Chademo group. The non-Japanese OEMs decided to make their own standard. They also didn’t like needing two sockets on the car, so they designed a plug that added two big pins to J1772, so the socket could work for both CCS and J1772. It also started at just 50kw, but today has grown to as much as 350kw which is just rolling out now. It’s still a very big plug compared to Tesla.

Normally it would have been OK to have different standards on different continents. But Nissan sold a lot of cars in the USA and Europe and so pushed a lot of Chademo outside Japan. In the end, the standards started to fight, and still do, though a large fraction of new DC Fast stations support both. The actual core function is the same, but each plug uses a very different data protocol to control how it happens.

Tesla built out its superior supercharger network fast, and quickly came to dominate. For several years, Tesla was really the only choice for a car that would ever leave town on a road trip. In 2020, a big build out (partly financed by money VW was forced to pay over dieselgate) will change that. The Chademo/CCS network is now starting to match the Tesla one in coverage, but while Tesla stations are at 150kw and have 8 to 40 charging bays, most of the “standard” stations do only 50kw and have just 1-2 charging bays, at least for now.

Tesla also put billing protocols into the charging plug, so you can just drive up to a supercharger and plug in and it all works — plug and play. With all other stations, billing is done a dozen different ways, usually by tapping a card or a phone with the right app onto the station before you can pull out the cord.

The companies don’t resolve this partly because there are differences, but largely because of pride and stubbornness. When you put your effort into something, you want it to be the winner. The many manufacturers who got together to make CCS feel proud that they cooperated while Tesla stayed proprietary. Tesla feels obvious pride that theirs is better and much more widely deployed and useful.

The obvious but unlikely solution would have been for everybody to just adopt Tesla’s superior plug. There are reports that Tesla was willing to make this happen early on, though Tesla also built its superchargers at great expense (and gave free unlimited use to early Tesla buyers) because they wanted everybody to feel the Tesla was the only car you could road trip in. They had reasons to not let other cars use their chargers even if the plug was the same. Tesla also spent a fair bit of money giving Level 2 chargers with Tesla plugs to hotels around the world to encourage Tesla drivers to stay at their hotels. The hotels pay for the electricity, and want to serve guests in any kind of car, but Tesla didn’t give them free gear for that. Even so, Elon Musk has said the Tesla charging network does not need to be a walled garden. An adapter is available to let non-Tesla cars charge at the Tesla level 2 chargers.

Today, Chademo is trying hard, but with VW’s big network in the CCS alliance, it seems to be on the losing side. (The VW stations include Chademo, but they might include far fewer Chademo ports than CCS ones.) Europe decided to push everybody to the European version of CCS (which is like CCS in North America but using the European Level 2 plug as part of it.)

Tesla’s adapter does only Chademo because it happens that both Chademo and Tesla Superchargers use the same data protocol over the wire. Teslas made for Europe can talk the protocol used in CCS. Eventually, as CCS wins over Chademo outside of Japan, Tesla will probably create an adapter able to do the hardware end of the protocol conversion and do the rest in software.

Europe

The situation in Europe went differently for both Level 2 and 3 charging. Level 2 charging eventually standardized on what’s known as the Type 2 connector. It’s similar to J1772 but it can carry all 3 phases of commercial 3-phase power. European CCS adds extra high power pins to that in the same way American CCS adds those pins to J1772. Tesla started with the Tesla connector in Europe, but switched under pressure to use the European CCS connector in new Model 3s. (By this point, CCS had improved to have similar abilities to Tesla’s connector, though it is still much larger.)

In Europe, it is not uncommon for charging stations to not have a cable. Cars are expected to carry a cable to plug in. This allows cars that don’t use the Type 2 connector to just carry a cable that will plug their car into the station. This is a bit more work for the driver, but has the advantage that the stations do not have an expensive cable sitting out which is worth stealing for its copper.

Those outside the USA/Canada/Japan have always had a modest advantage for home charging, because plugs in those places carry 220v at 16 amps, compared to the 120v at 15 amps found in USA/Canada. Proper Euro household plugs can deliver 2.8KW compared to the 1.5kw in the USA, usually enough to more than fill an average day’s driving.

Chademo got a strong start in Europe, again because of the Nissan Leaf, but European regulators made a strong push to promote CCS, effectively regulating it away.

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