SAE Releases EV Quick Charging Standard, But Debate Continues

By · October 15, 2012

CHAdeMo versus Combo Cord

You say Combo Cord (top) and I say CHAdeMo (bottom). Let's call the whole thing off.

After years of discussion and wrangling, SAE International today announced that its new technical standard for the quick charging of electric cars and plug-in hybrids has been approved and published. Any characterization of this new standard as a “breakthrough” or “game-changer” should be taken with a giant grain of salt—because, in fact, it does nothing to resolve the debate about the best coupler device for EV quick charging.

Many industry insiders see it as a step backward. Arun Banskota, president, electric vehicle services at NRG Energy, a few months ago told me, “The longer this continues with more than one standard, the more challenging it is for service providers like ourselves, and for consumers.” Kristen Helsel, director of EV Services at Aerovironment, a manufacturer of EV charging equipment for more than 20 years, added, “We’ll have to develop multiple products, so it makes it more expensive,” said Helsel.

I have already lost hours of my life trying to make sense of DC Quick Charging standards, so let me share a transcript of (an imaginary) conversation between proponents of the CHAdeMO protocol and the new SAE combo chord.

Fly on the Wall

Pro-CHAdeMO: Our plug works! Why fix what ain’t broken? It’s out there and being used everyday by EV drivers.

Pro-Combo: Are you kidding me? One thousand or so CHAdeMO quick chargers, and 10,000 or so cars that can use them? That’s nothing. It’s completely nascent considering that the EV market will grow to 1 million or more in the next five years. Let’s build the right plug for the long haul.

Pro-CHAdeMO: Combo chord doesn’t improve anything. Your approach just derails our momentum. It's a poke in our eye, just because we led the way. We already have the right plug.

Pro-Combo: That heavy ugly toe-breaking monster? Our DC Combo cord is a smaller and lighter connector. One thing to connect is better than two things. Read my lips: One is better than two.

Pro-CHAdeMO: But drivers never use AC and DC charging at the same time. Combining the cords is a non-issue.

Pro-Combo: But our inlet can use the gasoline filler door, which saves a lot of money instead of punching a new hole in the sheet metal, just because it’s an EV.

Pro-CHAdeMO: That makes no sense. Cost reductions will not come from a new piece of hardware. It’ll come from reaching production scale. That scale is already underway by companies that really believe in EVs, not you guys [pretending to cough while under breath, saying “GM, Ford, Germans”]. Scale will come from companies most committed to EVs and who build them from the ground up, and are those using CHAdeMo.

Pro-Combo: Your communications protocol is so yesterday. We’re using power line communications (PLC) so we can link up to the web.

Pro-CHAdeMO: Excuse me. Our cars are already wirelessly connected to the web. Besides, we use CANBUS communication. That’s the on-board communication system that allows the charging equipment to know what’s going on with the battery, its state of charge, and health. Puleeeze.

Tesla: Yoo hoo. Hey guys. We’re over here. Our cars use the same small sleek connector for Level 2 and DC Quick Charging. It’s smaller, simpler and faster than both of your approaches.

Chinese EV Makers: Hello? How come we didn't get an invitation to this meeting? Did you see our charging plug and outlet? In case you forgot, we’re the biggest auto market in the world, and soon will be the biggest EV market in the world.

Round and round it goes. Let’s face it. There are no standards for quick charging.

And after more than a year-and-a-half with my Nissan LEAF, I have yet to use my DC Quick Charge port. When my lease is up, and I shop for a new EV in early 2014, the last thing I'll worry about, or pay extra for, is a quick charge port.


· Spec (not verified) · 5 years ago

Standard is better than better.

I don't really care which one is selected as long as ONE is selected.

Due to that alliance of US and German car makers lining up behind the SAE Combo standard, I say go with it.

The Tesla is the laserdisk of charging. It is a bit better than Beta and VHS but the market is so small that it is pointless.

· · 5 years ago

Spec, why should we have to go with the US/German standard? Those companies don't seem to be interested in producing EV's. At least Nissan/Mitsubishi/Tesla have cars with fast charging out already. I'd be happy if the Tesla or CHAdeMO standard won.

· LeafLuvr (not verified) · 5 years ago

I have used the CHAdeMO charger option on my Leaf after a year of owning it and found that it definately changes the whole picture with respect to range and convenience. The enemy of any budding technology is "Standards wars". I can see what they are selling here with having one plug for all cars, but with Infiniti looking to launch their new sedan with induction charging as standard, I am not sure this is a fight worth having.

· vbsdan (not verified) · 5 years ago

Someone needs to show these guys the connector that Tesla has come up with for their Model S, which incidentally uses the same connector for Level 1, Level 2, and for their new DC Superchargers at 90 kW. It's about one third the size of those other two monsters.

· KellyOlsen (not verified) · 5 years ago

This is all ego based and has nothing to do with what is better for the consumer. The people at SAE got their nose in a twist and now want to muscle their name into this issue. Beta vs, VHS, BluRay vs, HD DVD, it is all silly and nothing more than a bunch of guys touting the size of their "package."

What we have now is working. Stop this insanity.

· JohnE (not verified) · 5 years ago

That's the nice thing about standards. There are so many to choose from.

· Anonymous (not verified) · 5 years ago

Thank you for the breakdown, Brad. That's very good!

· Spec (not verified) · 5 years ago


I'm not sure what you are not understanding. The most important thing is to get ONE standard that everyone agrees to support. The SAE (Society of Automotive Engineers) has picked one that has the LARGEST BACKING of auto makers. That is why we should go with it.

Think about this . . . building out a charging infrastructure is going to require some government support in terms of incentives, regulations, etc. Do you think the American and German governments are going to help out a proprietary system from Japanese automakers? No. Go with the system backed by the largest consortium of industry participants.

Yeah, Nissan & Mitsubishi have some cars out now. Well, in the USA the number of ChadeMO cars & chargers is statistically insignificant. Nissan & Mitsubishi should just quickly adopt the new standard and be the first companies on the market with an SAE Combo plug.

· · 5 years ago

I had a chance to meet executive officers from an Arizona-based company, GoE3, this past spring. They're proposing to install Level 3 EVSEs across the US that are modular in nature. Each EVSE would feature CHAdeMO, SAE J1772 Combo and Tesla plugs. Their theory is that one (not all) of these Level 3 standards would surface as the dominant one over the next several years. As the proverbial handwriting appears on the wall, they can simply revisit their remotely located EVSEs and swap out the modular circuitry relating to the standard(s) that are no longer current and replace with modules that are. This, in essence, makes the EVSE "future proof."

So, assuming this could an industry model for all Level 3 EVSE installations, the problem of multiple plug formats and the inevitability of only one format winning is a pretty simple one to solve. You can read about it and stream audio from here . . .

· Spec (not verified) · 5 years ago

"And after more than a year-and-a-half with my Nissan LEAF, I have yet to use my DC Quick Charge port."

Yep. This is why a single standard is needed. No one is going to want to fund fast-chargers in confused market without standards. Benjamin's post mentioning a multi-standard is an attempt to resolve the issue but that is a lot of hardware that will be designed, not used much, then discarded.

I think it is great that Tesla built a few fast-chargers in California. But anyone that believe they'll install all the rest of those chargers in the coming two years is in for some disappointment.

· · 5 years ago

I love this debate. Very good.

Tesla won this by a landslide. These guys think outside the box. Look how small this is.

I can't see consumers manhandling either of the other two designs. Their GIGANTIC, and they only look safe to use by a utility company lineman.

The manufacturers take a close look at licensing the Tesla design.

· · 5 years ago

I have had my Leaf for a year and a half and I just fast charged for the first time this week. It was nice. I drove to another town, did my business there, went to the restaurant with the CHAdeMO, ate lunch and came back out to a 70% charge. I configured the charger to stop at 70% when I plugged in. I then drove off with enough juice for the rest of my day's needs.

The EVs of the EV1 era had small paddle, large paddle, AVCON... it is sad to see it happening again. It is like we learned no lessons from this past experience.

A fast charge network really does help make EVs more useful. If this rift divides the fast chargers and/or makes them more expensive, it will hurt the industry. At these power levels, you can not simply jury-rig an adapter with parts from Home Depot like you can with a dryer outlet for level 2 charging.

· · 5 years ago


What do you think we should standardize on? Horse saddles with stirrups or do you think we shouldn't allow stirrups in order to standardize our saddles so we can buy them from anyone.
Let's not even get into saddle horns. Nobody will be able to use a horse for roping since English saddles, coming first, will have to be the standard. Sorry cowboys.
Your choices will be bareback or tiny English saddles without horns. We will not permit any improvements since that would violate standardization.

Personally, I'm not a fan of strict standardization. It gets in the way of optimization and revolutionary improvements. It has its place, but IMHO it is way too early to worry about standardization of EV charging.
Were I to choose, I'd choose Tesla hands-down over all of the other junk being proposed. The ICE industry will, undoubtedly, never go along with supporting Tesla though.

· Harvey_Titan (not verified) · 5 years ago

I am a Leaf Owner with CHAdeMO and I live in the Pacific Northwest, so I have ready access to a whole bunch of CHAdeMO and a car that can use them. This system is working, and I feel sorry for the honest EV enhusiats that live outside the Northwest. Here I can already travel through a large area of urban and countryside with access to Fast EVSE. I understand their frustration and hope that soon they will enjoy the same level of access to Fast EVSE we do here.

What is disturbing is that motor companies that don't see one bit serious about the EV market are using the SAE Combo as a delaying tactic against Nissans' leap ahead of the pack with the Leaf. Sour grapes! And I am not sure why I would care one bit about the opinion of someone that is waiting to buy an EV till what, the availability of the SAE Vapor Ware DC Charger? They missed the boat a long time ago. Those are the folks that would have delayed buying a Model T till something better came along.

· · 5 years ago

Here in the northeast, we are seeing the effects of this battle first-hand. NYSERDA (New York State Energy Research and Development Authority) recently announced a large sum of grant money to develop EV charging infrastructure. I contacted them directly to inquire about the possibility of L3 infrastructure, especially along the thruway (which runs through all major cities in NYS, from Buffalo to NYC). The response I got was that they are aware of the competing standards, and don't want to pick winners/losers. Therefore, all the money is going to L2 (yawn), and we get to wait until it is clear which standard wins before getting any L3. Once again, NYS cedes the leadership role to the west coast.

· Spec (not verified) · 5 years ago

@ex-EV1 driver

Really? Do you wish you had to go to a Ford gas station if you have a Ford and Chevy gas station if you had a Chevy. You really don't see the point? Luckily the auto industry knows better.

· · 5 years ago

Regular, Premium, Diesel, Leaded (which I can't get anymore for my old car that needs it). Gosh, how can we live if everything isn't exactly the same. Horrors!!!
Yep, I'm aware of the situation quite well. We live with it all the time and it doesn't hurt much at all.

· Spec (not verified) · 5 years ago

Regular, Premium, Super-premium . . . I can put any of those into my car.

And the fact that you had to refer to a gasoline variety that doesn't exist anymore weakened your point and showed how it sucks to have different versions! LOL!

There is a difference between gasoline & diesel but it certainly would be easier for the oil industry and everyone else if there were only one liquid fuel!

If you starting from the very beginning, it is much easier to have a single standard since that one single charger could charger ANY EV then.

· · 5 years ago

@Spec: "And the fact that you had to refer to a gasoline variety that doesn't exist anymore weakened your point and showed how it sucks to have different versions! "

Leaded fuel did not go away because it "sucks to have different versions". It was regulated away because of the pollution associated with it. And you may be able to put any of those into your car, but you shouldn't. You should use what's recommended because that's what your car is tuned for.

I agree with ex-EV1 in that "We live with it all the time and it doesn't hurt much at all." Yes, a few places (mostly the west coast, Chicago and Tennessee) have a growing CHAdeMO infrastructure. However, the EV movement has only but begun. Yes, there are 30k+ EVs worldwide which support CHAdeMO (my Leaf is not one of them). But there are 150 MILLION cars in the US alone. This is exactly the time we should be working on getting the "right" standard, not just the "first" standard.

· Tony Williams (not verified) · 5 years ago

So, officially today, we have the Renault Chameleon 43kW / 22kW AC fast charger, Tesla 90kW-120k DC fast charger, CHAdeMO, Chinese standards, and last and late to the party, SAE. I note this didn't specify that the European and USA version of this "standard" won't be joined until at least 2017 (if ever).

The right "standard" for EV charging is likely to be none of the current offerings. All of those are limited in speed (compared to oil burning cars). I suspect we'll go to some under the car, automated system to charge the battery at 1,000kW (which is way too big and dangerous for the general public to handle directly with 2" diameter conductors). And some fleet battery swapping. People would complain about that, too, though. Still too slow.

So, what to do today. The reality is the newly created SAE "Frankenplug" is coming; it is neither better or specifically worse than its competitor, CHAdeMO. Both have the same basic speeds and big clunky connectors.

It's common for the Frankenplug supporters to call CHAdeMO a proprietary Japanese standard, even though it is neither proprietary (as of August 2012) nor only in Japan. It is in Europe (250 units), USA (approaching 100), UK ,Russia, Middle East, and more. This new SAE standard has precisely zero cars and zero charge stations.

None of the eight or nine Frankenplug supporting manufacturers, with the lone exception of BMW, have plans to use this standard for anything more than California "compliance" cars; those that are built only to satisfy that state's zero emissions requirements. Fewer still have plans to use it at all, with only GM and BMW with announced cars.

Frankly, it will be a rocky road for Frankenplug.

· Bill Howland (not verified) · 5 years ago

To these eyes the standard seems very poorly thought out, even amateurish. This means that 2 high power wires lay dormant (increasing the cable heft for small women, for instance), and accomplish nothing towards charging the car.

Of course the original J1772 standard was so poorly codified that many different brands of chargers do *not* work with J1772 cars since the standard was so loosely defined. They should have 2 high power posts for a single phase ac feed, and reuse the same wires for DC high power. This thing appears to me to be so bad that a competing standard will appear soon enough

· SPIKE (not verified) · 5 years ago

These various L3 standards could co-exsist just like there are multiple wall outlets voltaage and connection standards. Electric cars are sold locally just like other electronics are. Maybe in the future you will be able to specify which L3 connector you want with your EV. And if your car dealer does not offer the option you need I am sure there will be an aftermarket solution.

Or perhaps things will be easy on the consumer and the connector that has market dominance will be the defacto standard.

· Bill Howland (not verified) · 5 years ago


I would have posted on the GreenCarReports site but its too hard to login there for someone who isn't on Facebook.

Point 1: Tesla's Model S connector shows some intelligent thinking, that's true.

Point 2: It's another non-standard plug, just what we all need, including incompatibility with tesla's own Roadster owner's equipment;; the Blog said an adapter would be needed to go between the existing Roadster charging hardware and the new model S. Unfortunately, I'm not aware of Tesla offering this adapter. Maybe on the new "buy back program" they will buy back the HighPowerConnector also?

Point 3: Tesla was indeed invovled in early J1772 standards, but chose to eschew them because I was told by Tesla the current j1772 at the time was 30 amps, (its now 80) and they wanted 70 and couldn't wait. I think that was a critically bad decision, as much as I think the j1772 is a dopey standard. Charging the Roadster at a 70 amp rate apparently doesn't happen for all that long anyway, and while it is happening the power input / battery soc gain is rather inefficient, in other words, quite a bit of the juice turns into electric heat. The most efficient rate to charge a Roadster is 30-40 amperes.

My view is that there are few of the powers that be that apparently care about standards. If this was 30-40 years ago I don't think most people would have accepted this. I did not accept Tesla's charging solution ( I've been told by Tesla I'm the only US customer who hasn't, hehe. that's why I bought the j1772 adapter a day before the car)..

This whole group of competing products is probably due to manufacturers wanting to get on the bandwagon and make their product the 'defacto' standard before anyone else does. Unfortunately, there are not enough EV or PIHybrid sales as of yet to force a shake out of the market.

Tesla's solution probably should have been the standard, all things considered... But then other bloggers are correct when they say Tesla put too much design effort into a latch that opens when you get near the car. Way too much complication,and a great opportunity for something to break down when a simple hand operated latch would have been fine.
GM has the same kind of problem with some of their recent gasoline filler caps. The filler pipe starts rusting a bit and then you can't get the gas cap off. I'm aware that provision needs to be made for evaporative recooperation in a charcoal canister, but its another indication GM likes to fix things that aren't broke, by breaking them.. This Tesla thing looks like its going down the same path, but hell, the warranty is good for a while right? hehe.

Its reminiscent of GM deciding the 100 year old battery post design was no good, and came out with those attrocious side post batteries. So then we had a defective wire connector attached to unbelievably horrid Delco batteries which were much more junky then anything from years before even that. I notice the aux battery in my Volt has gone back to the 100 year old posts, hehe.

There's currently a cacaphony of too many different connectors, on something that looks to me to have been a super high markup item due to collusion of electric equipment charging providers (something not unknown to the NEC/NFPA - the aluminum romex debacle in the 60's-70's was also due to similar collusion and is unacceptable due to the number of houses burning down - we'll have to see how many garage fires of the future are because of poorly designed charging apparatus).

I suspect many of us are just going to sit this out until a lower cost resolution is provided by a more mature industry.

In the meantime it causes many potential EV owners to just suffer along with standardized 110 volt charging, or is just another issue to scare them away completely.

Thats the real crying shame here.

· · 5 years ago

@Bill Howland,
I think your points miss some historical and cause/effect perspective:
Point 2: The adapter from legacy Roadster chargers to Model S exists today and all former Roadster Owners that have bought a Model S has received one.
Point 3: The Tesla Roadster was out 2 years before J1772 was finalized. Their connector is electrically compatible, just not mechanically. You also may not understand the causality. The J1772 committee was dominated by the traditional ICE companies. GM was trying to protect the Volt so they didn't want to allow anything but 40 mile charging overnight and the rest wanted to stall J1772 as long as they could because they had no desire to produce EVs at all. All were very happy stalling Tesla to keep an upstart out of their club. IMHO, Tesla going out on their own, doing the right thing with decent charging speed was the best one could have done.
The Roadster charges at 70 amps up to about 85 - 90% SOC depending on the ambient temperature. Have you even tried 70 amp charging?
I have to question the judgement of anyone who spends over $100K on a car but then cheaps out over buying a $1500 charger and suffer with 110v charging. I do know people who do so because their house wiring would require extensive rewiring but refusal to accept the non-standard is unnecessary stubbornness.
When we got our Roadster, there was no such thing as J1772. I'm so glad Tesla didn't wait or J1772 might never have been completed - no matter how bad you think it is. I credit Tesla's lead with their Supercharger for pushing the SAE to finally finish the frankenplug - no matter how bad I think it is.
You may choose to sit by the side and wait but that isn't how a revolution gets started. I know a lot of folks who took that attitude with the 1st generation of modern EVs and decided they would just wait until " a more mature industry" happened. It took over a decade and a lot of foresighted pioneers before what you enjoy today even happened.
I hardly call what we have today a 'cacophony'. There is one connector that every EV today can use except the old RAV4EV - J1772. If one wants fast charging, there are only 2 incompatible standards - hardly a cacophony. One can also use the plethora of 240 volt plugs out there with very little effort. Tesla has supported them for nearly 3 years already and it is easy to modify an SPX or EVSE upgrade to take any standard NEMA plug.
As a wiseman said a few years ago, if you want the EV that perfectly suits your needs, you will have to buy the one built today that comes closest or your perfect one will never be built.
Another said: Perfect is the enemy of 'good enough'

· Bill Howland (not verified) · 5 years ago


Well perhaps.... But my charging info was from that engineer who died in the plane crash a few years ago.. He had a blog where he compared all the different charging rates.

As to price, yeah on a $109000 car that's true... But I sympathize with people who make less money than I do, and frugality will be necessary if we're ever to get widespread adoption of EV's.

I'm not yielding on the confusion point though. I've talked to too many people who are not amused by nonstandards and is causing them pause.

· · 5 years ago

@Bill Howland,
If the non-standard DC Fast charging is causing someone a problem, they probably aren't cut out as a pioneer anyway. They probably will have to keep buying gasoline, irregardless of the price, and wait until a lot of other things become easier with EVs as well.
To me, the problem with DC Fast charging is that there isn't very much!
As Michael points out, EVs aren't for the average driver yet. They take a bit of thinking.
Widespread adoption will take more infrastructure and, more importantly, EV savvy, knowledgeable teachers to explain (in simple terms) what one needs to do to get somewhere in an EV.

· Bill Howland (not verified) · 5 years ago


This ties in with what you just said. I went to "Buffalo Green Projects" with my Green Roadster, and won the "Most Green" Trophy. Why I don't know exactly, but I was:

A). The most expensive car there (the most greenbacks)
B). The only fully electric car (most environmentally green)
C). The only Green color there.

During the festivities someone drove up with a One week old Volt, and they explained they specifically came to find out how to USE THE ELECTRICITY! (hehe).

One of the attendees showed them how to take the '110 cord' out of the trunk and plug it in the wall, so as to facilitate gasoline savings. They were very happy!

· · 5 years ago

@Bill Howland,
That's the first time I've heard of someone who couldn't figure out how to plug a car in. I guess they don't have much experience with laptop computers or cellphones either. I really don't see much of a difference.
This anecdote definitely supports Tesla's position of not using dealers to sell their cars. Whomever sold this person their Volt should definitely be fired.
I fully support the idea of charging stations that automatically connect to the car. However, given the amount of complaining I hear about how expensive chargers are today, I've basically written such expensive additions off as being way in the future, after the market has grown large enough to be able to bring the price down on such complicated technology. With today's sales volumes, such a charger would probably cost half as much as a car.

· Bill Howland (not verified) · 5 years ago

OH, I would surmise that once the people were visibly shown how to plug in the car into a 110 outlet , that they'd remember how to do it a second time. No big deal.

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