You take your ICE car to a petrol station. Whatever brand of petrol you are trying to buy, the nozzle fits your tank. Whether you buy your car from Tata, Mahindra, Maruti or one of the exports, it still manages to fit your tank. The reason for this is the oil industry agreed on a standard design and diameter size for the nozzles.
When it comes to EV, because they are relatively new to the market than the firmly established fossil fuel industry, there is a fight for the right standard to be used on cars or the one govt would like to regulate. There are several standards all fighting for their right to be the one.
The war of the plugs
Let’s have a look at some of the common regions of the world and why I think CCS is a standard to depend on for the future.
As you can see from the image, the Japanese and Chinese would require 2 different charge ports to support AC charging at home and DC Fast charging when out and about. This means you require 2 charge ports on the car.
For reference here are the Nissan Leaf’s charge ports. One for the DC fast charging CHAdeMO and the other a Type 1.
Here’s one with Type 2 instead of Type 1, probably because it was built for a different region.
For the manufacturer, this leads to added complexity in their manufacturing and supply processes to support multiple standards.
Here is the Tesla China Model 3 with 2 ports to support the local government regulated GB/T and the Type-2 standard for the Tesla Super Charger and home charging.
We can see that just from the design standpoint, the CCS(Combined Charging System - the name says it all) is a well thought of approach into standard design. Why do you need 2 separate plugs for AC and DC charging, why not have 1 design that can do the handshake and communications on the common pins and use the AC probes or the DC probes depending on the outcome of the handshake.
Here’s a Kona with a CCS2 port.
The upper half can be used with a Type 2 connector for AC charging upto 22kWh and the lower half is for the fast charging DC that in theory can support upto 350kWh depending on the vehicle side of things.
It takes half the space as adding 2 ports and if the vehicle designers think hard enough, it can even find it possible to hide behind a tail light as in the Model 3.
Porsche is an odd one who seem to be showing lack of knowledge and adding 2 ports for all regions.
Exactly why a redundant type 1 and type 2 required for AC charging when the Combo ports can be used for the same task is anybody’s guess. Perhaps some genius at Porsche thought, “Hey, we are making 2 holes for the Chinese and Japanese variants which will be left empty in US and America. Let’s not build a special panel for these markets and provide an additional AC port instead." I wonder what happens if 2 AC chargers are connected on either side. Someone willing to experiment?
Access to Specification documents
CHAdeMO is a proprietary protocol that has now been turned into a standard. The protocol was made by the CHAdeMO association which is a group originally comprised of Japanese Automotive manufacturers. It now has members from around the world. CCS on the other hand is an open protocol by a group called CharIN which has several companies as its members. If you want to get a CHAdeMO specification, you can buy it from the IEC or IEEE website or become a CHAdeMO member. For the CCS specification, you just visit the Charin website and put a request here and they send you an email with several PDFs. They do have a membership option too for other detailed info and access to reference designs, but at least you don’t have to pay if you are just curious to learn about the specifications.
CHAdeMO uses the CAN bus protocol for communications between the charger and the Car. CAN is a protocol that has been used by the automobile industry since 1986 when Bosch first introduced it. This protocol is used to pass messages between the various microcontrollers in the car and requires a separate set of cables for data communication..
CCS on the other hand uses the Homeplug Green PHY which is a specification of powerline communications, which uses the same cables that are used for carrying AC current. This protocol is being used by a lot of modern day smart appliances like the smart meters, and other home appliances like smart fridges, etc. This leads to less cabling requirement when building the car and charger.
Both the charging protocols have several members from the industry. We can look at them CHAdeMO and CCS, but the list won’t tell us much. Why? On both the members list we find companies like Tesla, Mazda, Suzuki, Volvo, Toyota, etc. We know that Tesla does not make cars with builtin CHAdeMO support. However, they do sell an external adapter to support regions that have CHAdeMO chargers deployed and that includes the Japanese market, US and Europe.
However, a better way to look at would be which other OEMs have cars with one of these protocols installed. From the EVs in the market, it looks like the only companies that have CHAdeMO built into them are the Japanese cars, but even those companies seem to be turning it’s back on the protocol. For example Nissan Leaf has traditionally been a CHAdeMO, but Ariya will come with CCS2. The Honda e has CCS2 and so does the Clarity. The neighbours don’t seem to favour them as well. The Korean EVs Hyundai Kona and Kia e-Niro are sold with CCS2, Kia Soul EV was the only CHAdeMO, probably built to test the waters. OEMs from US and Europe choose the CCS2 standards at least for non Japanese markets.
Right now chargers are being installed with support for both, but as more companies ditch CHAdeMO for CCS2 on their cars, the chagring industry will tip their support towards the side that is more commonly available, the reason being it’s cheaper to manufacture and support 1 protocol than having to build chargers that support 2 different protocols.
One advantage that CHAdeMO has right now over CCS is that they support Vehicle to Grid (v2G), which is a way to use the car as a battery backup for the electrical grid or the house. Think of it as a portable powerwall. CCS will be making this a part of the next revision and will be available by 2025. This does not mean existing cars will suddenly start supplying power to the grid one day after 2025. Only new cars sold by then will support it due to the hardware limitations of the older cars. Perhaps a component upgrade could be offered, who knows?
Having multiple standards is a waste of both time and money. The amount spent on supporting multiple standards could have been spent on supporting just a single good one. One of the standards would see less use and due to lack of vehicles supporting it and eventual abandonment.
As we see above, CCS not only provides savings when manufacturing the vehicle, be it due to the design of a common AC/DC port or the lack of additional communication data lines as an advantage of HomePlug Green PHY protocol but also it has a larger industry support and will eventually drive the charging industry to support the Winner. If I had to compare this to the videotape format wars of the 70s and 80s, CHAdeMO is the Betamax and is losing the battle to the VHS of charging, the CCS.
By - Sam Albuquerque
Team Tesla Club India
Building a Community for the Future