CharIN and CCS, CHAdeMO,

[jbcarioca]

There has been an increasing amount of discussion about various alternative charging solutions including quite a few confusions about present vs future capabilities of various technologies. It seems to me we need a dedicated thread on teh subject;

Long Tail Pipe does have a superficial be useful comparison of standards:

EV DC Fast Charging standards – CHAdeMO, CCS, SAE Combo, Tesla Supercharger, etc

CharIN (Charging Interface Initiative) began with German automakers but now includes almost everyone, including Tesla. The CCS/SAE Combo is the common descriptor of user interface:
http://www.charinev.org
Files of the CCS Design Guide and Specifications are attached.

CHAdeMO has lots of information about present and future developments on their site. I have not attached any files because this is probably better known to Tesla people:
CHAdeMO Association
"CHAdeMO is an abbreviation of "CHArge de MOve", equivalent to "move using charge" or "move by charge". The name is also a pun drawn from O cha demo ikaga desuka in Japanese,[1] translating to English as "How about some tea?", referring to the time it would take to charge a car..." from CHAdeMO - Wikipedia, the free encyclopedia

SAE J1772 is usually a work in progress, but the traditional J1772 plug has been incorporated as part of the North American version of the CCS (often called SAE Combo). I link to the iwki, because that is the most concise source I know:
SAE J1772 - Wikipedia, the free encyclopedia

I hope knowledgable people among us, or at least opinionated ones, will discuss all this and the Chinese standard too. I did not mention Superchargers but they clearly are included.

 

[RDoc]

From what I've read, the CharIN (CCS) standard is kind of stuck for it's maximum amperage so is going to have to significantly up the voltage to increase power. Unfortunately, the documents and CharIN site seem to be silent on this, but if that's the case it will require an entirely new generation of batteries to use I'd think.

We'll see of course, but it all seems pretty bureaucratic to me.

 

[widodh]

From what I've read, the CharIN (CCS) standard is kind of stuck for it's maximum amperage so is going to have to significantly up the voltage to increase power. Unfortunately, the documents and CharIN site seem to be silent on this, but if that's the case it will require an entirely new generation of batteries to use I'd think.

We'll see of course, but it all seems pretty bureaucratic to me.

They will go to 300A 500V, which is 150kW at max.

Tesla is running into about the same problems. They max out somewhere around 340A, but at some point you can't simply put in thicker cables.

So CharIn/CCS is indeed going to bump the voltage to 1000V. That doesn't require new batteries, just a new way of configuring them inside the vehicle.

Using relays/switches you can change a 400V pack into a 800V pack on-demand, no problem.

Tesla will probably do the same at some point.

 

[jbcarioca]

There are several serious issues as total power increases. Tesla already has used liquid-cooled cables, partially addressing the heat dissipation issue as electron flows rise. Battery Management Systems are another major issue, one in which Tesla has a major advantage today.

One big advantage for both the CharIN group and CHAdeMO group is that major utilities are participants. Every major public utility knows a great deal about high-voltage high-amperage electrical transmission, and about grid management too. They may not yet be doing too much publicly visible work towards "Smart Grid" but nearly all of them are experimenting with ways to store energy to mitigate peaks and valleys in both renewable power generation and energy usage.

Without question the standards and specifications are bureaucratic. That is in the nature of standards. The subject of EV charging is full of safety pitfalls as well as extremely complex grid management and billing issues.
That is precisely why the rapid adoption of BEV's is about to become seriously political. There are a number of studies that suggest EV charging is mostly contra-cyclical with other daily demand. That is because they charge mostly at night, and mostly with standard voltages and amperages. Even there demands will create porblems with multi-family housing, local and regional switches and the like.

One reason for this thread is to help us all become more familiar with all the issues. We are on the verge of major challenges to electrical distribution and usage.

 

[RDoc]

They will go to 300A 500V, which is 150kW at max.

Tesla is running into about the same problems. They max out somewhere around 340A, but at some point you can't simply put in thicker cables.

So CharIn/CCS is indeed going to bump the voltage to 1000V. That doesn't require new batteries, just a new way of configuring them inside the vehicle.

Using relays/switches you can change a 400V pack into a 800V pack on-demand, no problem.

Tesla will probably do the same at some point.

Sure I understand that, but it still means there will have to be new physical batteries to use the higher voltage and all existing vehicles won't be able to.

 

[jbcarioca]

Sure I understand that, but it still means there will have to be new physical batteries to use the higher voltage and all existing vehicles won't be able to.

That is not really correct. The CCS standards require for the vehicle to establish charging capacity. Just as tesla cars today impose tapering as they reach higher states of charge, in the CCS standards similar processes are used. the difference is in the use of AC to set charging limits while Supercharger and CHAdeMO use the CAN bus for that function. In any of the three systems the vehicle impose the charge limits, so all can use charging systems with higher capacity than the vehicle can absorb.

 

[Jeff N]

They will go to 300A 500V, which is 150kW at max.

Both CHAdeMO and CCS will go to 350A at 500V (which is 180 kW but they call it "150 kW" for whatever reason) and a short time later to 350A at 1000V. It may even be possible to do 400A for short initial periods of time until temperatures rise on the connector but they should both be good for 350A continuous with liquid cooling on the charger-side cable and plug.

 

[jbcarioca]

Both CHAdeMO and CCS will go to 350A at 500V (which is 180 kW but they call it "150 kW" for whatever reason) and a short time later to 350A at 1000V. It may even be possible to do 400A for short initial periods of time until temperatures rise on the connector but they should both be good for 350A continuous with liquid cooling on the charger-side cable and plug.

Both also have processes to increase limits as technologies develop. We all should understand that everyone involved in Supercharging, CCS and CHAdeMO is committed to establishing faster charging as vehicles advance to need and are capable of accept faster charging. The biggest impediments remain one related to cooling, for the batteries and for the charging apparatus. Any of us who've connected a tesla to Supercharge from a low SOC are aware of how hot the current Supercharging equipment can become. All three systems have similar constraints, in point of fact, even though the only current production EV's that test the limits are Teslas. Wait three years and there will be many others.

 

[emir-t]

AFAIK the limit with fast charging now isn't how much power you can deliver but rather how much the battery can take. And as long as battery capacity doesn't go way over 150kWh current DC fast charging would be enough right?

I thought batteries were the limit here. Be it a 1 kWh pack, a single 3,3Ah cell or a huge 100kWh pack, 80% charge will be in around 30-40 minutes and a full charge would be a little over an hour with these batteries. (given that you can supply the power)

It's about the c rates the battery can take. So although the 'filling up a liquid down a tank' analogy feels very intuitive it's not very realistic.

Correct me if I'm wrong; to charge at 1000V / 350A you'd need a 1000V pack. That's not impossible, Rimac already uses 600+ V battery, just connect enough of them in serires and it will be there. Assume that the pack's capacity is 100Ah, so a 100kWh battery. Just because this futuristic DC charger is able to dump 350kW of energy doesn't mean it can into this battery.

If you apply 3+ C to this battery it will just reach its peak voltage way early (and shorten its lifetime) and you'll have to taper the current and have a constant voltage charge for a very long time. Overall charge time won't change. I guess we are looking into batteries getting bigger so that you don't actually need the 100%. Also as they get bigger because filling up 80% still takes the same time, filling up 80% of a larger battery means more miles charged per unit of time.

Charging x% in x minutes won't improve but charging x miles in x minutes will improve. And currently the bottleneck isn't power delivery but battery capacity. I guess they want that much power delivery to future proof? I don't think batteries will go over 120 or so kWh ever so they're future proofing what? Or are there cells incoming in that can charge at 3+ C continiously?

 

[miimura]

There are other cells that can charge and discharge safely and reliably at higher C rates. However, they are more expensive and less energy dense than what Tesla and other automakers want to use for long range EVs. EVs and Hybrids don't use the same kind of battery cells for good reason - the design targets are different. An EV needs energy density so that it can go longer distances. Tesla puts enough of these batteries in the car, so they get high power as a byproduct. A hybrid needs to get a certain amount of power in and out of the battery and doesn't need the energy capacity because there's an ICE. If you were to use a very large quantity of high power batteries in an EV, you could charge it in 15 minutes. However, it would require a lot more volume and it would be heavier than a typical EV battery pack of the same capacity. Everything is a trade-off.