why are Tesla charge connectors so much smaller than CCS etc.

[miimura]

I see most of this thread is from 2019, but there are some errors that should be corrected.

1. Supercharger V3 delivers up to 625A for short periods of time.
2. The Porsche Taycan and Audi eTron GT use a DC-DC converter to charge on DC chargers that can only deliver 500VDC. The standard one goes up to 50kW, but the Taycan has an optional one that can go up to 150kW. I don't know why anyone would pay for that since every 150kW charger I've seen can go up to at least 920VDC. There is no such thing as dividing the pack to charge in parallel at less than 500VDC.

 

[Frank99]

I don't see much value going higher than 250 kW any time soon since power limit is still mostly the battery at this point rather than charging infrastructure.

I'm in your camp on this one...

Tesla's 250-kW Supercharger Only Saved Us 2 Minutes vs. a 150-kW Charger

We tested each of Tesla's high-output charging stations with our long-term 2019 Tesla Model 3.

www.caranddriver.com

Tesla probably can't raise the current any higher than it is now for faster charging; it probably can raise the voltage at the same current to increase power. For example, perhaps the CT will have an 800V battery rather than the classic Tesla 400V battery (probably not, but let's use this as an example). With an electronics retrofit to enable 800V charging, the exact same cables that a 250kw Supercharger now has can all of a sudden support 500 kw. As was noted upthread, there may be limitations on the voltage based on the physical spacing of the contacts in the handle; someone with more knowledge than I would need to comment.

But even for a putative 250 kwh CT with a 400V battery, it's not clear that more than a 250kw SC is necessary. How long does it take to Supercharge a 75 kwh Model 3 from 0 to 100%? About an hour on a 250 kW SC according to the C&D link. How long would it take to Supercharge a 250 kwh CT at 250 kw? A bit more than an hour, but probably not much more - the charging rate could stay at 250 kw all the way up to about 75% charge (based on the C&D link above, where the charge rate drops to about 1C), then the charge would taper. Eyeballing the C&D chart, I might guess at about 15 minutes longer for the CT - 1:20 rather than 1:06. Probably not worth rebuilding all the infrastructure for that.

I really believe that, at some point, Tesla will give up on their superior charging handle and start equipping their cars and SCs with CCS, just like someday Nissan will give up on CHAdeMO. I'll predict that Tesla will ship a car with CCS in North America within 5 years, and it'll take a couple of years to transition their entire product line.

 

[Gasaraki]

I was looking at a video of the Taycan motorised charge port and the thing that struck me was how huge the socket and connector is. So many pins! How is that Tesla can create such a svelte simple connector whilst others have a bunch of pins, sometimes even double stacked like CC? Are Tesla just that much smarter or will they be unable to take advantage of faster charging speeds etc. later on?

Tesla is awesome like that. 3 pins, 250KW, communications, etc. Everything in a small 3 pin connector. The Tesla connector should have been the standard.

 

[Gasaraki]

Tesla made some fundamental tradeoffs by the smaller connector. They basically made it so the switching from DC to AC charging has to be done by the charger circuit, since the Tesla pins handle both DC and AC. CCS/J1772 completely separated the pins so you don't have to do any internal switching, you just have the DC charging pins directly connected to the DC circuitry and the AC pins connected to the AC circuitry.

Also, keep in mind Tesla uses the 'Type 2' connector in the EU since they handle 3-phase power. Same compromise as in the US, but it's larger since it has more pins for additional 3-phase power support. The Type 2 connector is larger than the US Tesla charging port.

I believe CCS is also rated for 1000V usage, whereas the Tesla ports are only rated for up to 500V. This has to do with separation distance between the two pins so therefore the CCS is inherently going to be a bigger connector. The Taycan is the first car I think that is supposed to utilize the 1000V, so it actually needs the CCS separation.

If Tesla ever decides to move to a 1000V system (currently they use 500V), then the connector would need to be redesigned. There's not a ton of reasons to actually move to a 1000V system for cars, as far as I can tell. For trucks (semis, etc), the higher voltage could be very useful since you no longer need to use such large connectors. Honesty, it seems to me the 1000V that the Taycan is advertising is mostly marketing than anything else.

Some info is wrong here.

The Taycan uses 800V charging and Teslas use 400V. For the Tesla Semis they use the Megacharger plug.

 

[Frank99]

Tesla is awesome like that. 3 pins, 250KW, communications, etc. Everything in a small 3 pin connector. The Tesla connector should have been the standard.

I wanted to answer the OP, but figured that two years was a bit late. You've given me an opening to fully agree with you.

why are Tesla charge connectors so much smaller than CCS?​

Because back in the noughties Tesla actually wanted people to drive EVs (as opposed to, say, Ford). They thought about where charging would be in the future (home AC charging and on-the-road fast DC charging) then designed and built the sleekest handle that they could. This design included the ability to supply either AC or DC through the large pins on the connector keeping it small.
CCS started out as a mandate by the California Air Resources Board, and reflects that - the resulting J1772-2001 standard had little in the way of forethought applied, it simply met the state-mandated requirements. In and of itself, the second-generation J1772-2009 connector (the current round one, including the EU Type 2 connector) isn't bad; the electrical signalling is archaic but the connector itself is reasonably small and robust. But without thinking ahead to DC charging, they ran into a problem when batteries got bigger and EVs became road-trip capable - and they solved it by grafting two humongous pins on the bottom of the J1772 connector to enable high-power DC charging. They couldn't simply reuse the same pins for AC and DC like Tesla did, because there were a bunch of cars and chargers that hadn't been designed with that in mind, and plugging them into newer chargers might have been disastrous.

Unfortunately, I'm afraid that Tesla's superior solution will end up losing out. With a dozen different charging networks installing CCS, and two dozen auto manufacturers building EVs with CCS, the Tesla connector is going to get buried. When an airport wants to install EV chargers in the parking lot, or City Hall wants to install them on the street, or Walmart wants to put them in the parking lot, they're gonna choose CCS.

 

[Tam]

...the Tesla connector is going to get buried....

Unless Tesla owners become the majority on the road because charging companies start to realize Tesla's popularity and decided to integrate Tesla Connectors together with their CCS stations as well.

 

[Suspect]

I see most of this thread is from 2019, but there are some errors that should be corrected.

1. Supercharger V3 delivers up to 625A for short periods of time.
2. The Porsche Taycan and Audi eTron GT use a DC-DC converter to charge on DC chargers that can only deliver 500VDC. The standard one goes up to 50kW, but the Taycan has an optional one that can go up to 150kW. I don't know why anyone would pay for that since every 150kW charger I've seen can go up to at least 920VDC. There is no such thing as dividing the pack to charge in parallel at less than 500VDC.

V3 Superchargers actually go up to 631A and Model 3 can accept it briefly. Not much indication of what these stalls can do in the future but it’s more likely that Cybertruck will just have a flatter curve to take advantage of 250KW charging.

 

[Gasaraki]

Exactly, 250KW charging is plenty fast. All they have to do is improve the charging curve. If the car can charge at 250KW from 10 to 80%, that would be a game changer.

 

[SageBrush]

Exactly, 250KW charging is plenty fast. All they have to do is improve the charging curve. If the car can charge at 250KW from 10 to 80%, that would be a game changer.

For now an average C rate of over ~ 1.5C between 10-80% SoC is not possible unless one is willing to accept accelerated battery degradation. Other than a novel chemistry development, what else can break that barrier ?

 

[id436eg9045]

For now an average C rate of over ~ 1.5C between 10-80% SoC is not possible unless one is willing to accept accelerated battery degradation. Other than a novel chemistry development, what else can break that barrier ?

So the alternative is to take the approach Audi used with the e-Tron and build a huge buffer into the pack. The e-Tron has 83kWh usable out of a 95kWh pack, which lets it maintain high rates of charge deep into the charging cycle. (150kW all the way to 80% SoC)

 

[SageBrush]

So the alternative is to take the approach Audi used with the e-Tron and build a huge buffer into the pack. The e-Tron has 83kWh usable out of a 95kWh pack, which lets it maintain high rates of charge deep into the charging cycle. (150kW all the way to 80% SoC)

That is not an alternative, it is marketing BS. Nothing stops me from calling my 50% SoC "100%"

 

[id436eg9045]

That is not an alternative, it is marketing BS. Nothing stops me from calling my 50% SoC "100%"

I disagree. Having that large buffer lets them maintain the pack degradation better over the long haul and it's transparent to the driver. For EV nerds manually figuring out degradation and knowing range loss is fine, but for most folks I think that having a consistent range over a long period of time that they don't have to think about is better. That's a functional decision IMO.

 

[SageBrush]

I disagree. Having that large buffer lets them maintain the pack degradation better over the long haul and it's transparent to the driver. For EV nerds manually figuring out degradation and knowing range loss is fine, but for most folks I think that having a consistent range over a long period of time that they don't have to think about is better. That's a functional decision IMO.

Whatever. Set your charge limit to 70% and call it 80%
Presto -- same result, same reason. Is this the intellectual challenge you think customers want to avoid ?

It is beyond moronic. Give me access to full capacity when I need it. One does not have to be a "nerd" to realize that charging the first half of the battery goes faster.

 

[Frank99]

Give me access to full capacity when I need it.

You realize that even Tesla doesn’t do that, right? Tesla engineering and marketing have chosen 100% and 0% points that don’t reflect 100% and 0% on the battery. There’s only a difference in degree between Tesla’s fudging and Audi’s fudging.

 

[SageBrush]

You realize that even Tesla doesn’t do that, right? Tesla engineering and marketing have chosen 100% and 0% points that don’t reflect 100% and 0% on the battery. There’s only a difference in degree between Tesla’s fudging and Audi’s fudging.

There is no reserve at the top, and the reserve at the bottom is usable.

 

[Frank99]

There is no reserve at the top, and the reserve at the bottom is usable.

Please define “top” and “bottom”.
Once again, they’re arbitrary points decided in by Tesla engineering and marketing.
“Top” is probably defined as “all battery cells are at 4.20 volts”, but they could just as easily have decided on 4.15 or 4.25 volts; 4.15 will have slightly less capacity but a longer life, while 4.25 will have slightly more capacity but shorter life.
“Bottom” is probably set at 3.0 volts per cell, but this is where the car shuts down, not where the range meter says 0 and the car warns you the battery is dead. They could have chosen 3.1 or 2.9 volts, but didn’t.
There’s a belief that batteries have an absolute value for “full” and “empty”. That’s not entirely true.

 

[SageBrush]

Please define “top” and “bottom”.

"Top": industry standard, aka 'nominal'
"Bottom": industry standard. Somewhere in the 2.5 to 2.6v range, I'm not sure

There are also top and bottom chemical limits, where top is defined by the half cell Nernst potential and bottom by irreversibility

----
You are attempting to obscure something that is straightforward in practical terms: the carmaker bought X kWh of capacity for a car and lets the consumer use Y kWh. X kWh is the nominal, industry set capacity rating.

 

[WhiteWi]

I wanted to answer the OP, but figured that two years was a bit late. You've given me an opening to fully agree with you.

why are Tesla charge connectors so much smaller than CCS?​

Because back in the noughties Tesla actually wanted people to drive EVs (as opposed to, say, Ford). They thought about where charging would be in the future (home AC charging and on-the-road fast DC charging) then designed and built the sleekest handle that they could. This design included the ability to supply either AC or DC through the large pins on the connector keeping it small.
CCS started out as a mandate by the California Air Resources Board, and reflects that - the resulting J1772-2001 standard had little in the way of forethought applied, it simply met the state-mandated requirements. In and of itself, the second-generation J1772-2009 connector (the current round one, including the EU Type 2 connector) isn't bad; the electrical signalling is archaic but the connector itself is reasonably small and robust. But without thinking ahead to DC charging, they ran into a problem when batteries got bigger and EVs became road-trip capable - and they solved it by grafting two humongous pins on the bottom of the J1772 connector to enable high-power DC charging. They couldn't simply reuse the same pins for AC and DC like Tesla did, because there were a bunch of cars and chargers that hadn't been designed with that in mind, and plugging them into newer chargers might have been disastrous.

Unfortunately, I'm afraid that Tesla's superior solution will end up losing out. With a dozen different charging networks installing CCS, and two dozen auto manufacturers building EVs with CCS, the Tesla connector is going to get buried. When an airport wants to install EV chargers in the parking lot, or City Hall wants to install them on the street, or Walmart wants to put them in the parking lot, they're gonna choose CCS.

At the same time while Tesla is number one EV seller in North America. As dumb as it gets brought to you by Gov.

 

[henderrj]

Actually the op's question is really easy to answer. ccs and chademo were both designed by committee, Tesla did it on their own. They could do the right thing, not the thing that made everybody happy. Not a huge compromise.

As to voltage and amperage, to boil it down to the most simple terms, higher voltage means higher chance of arcing, higher amperage means more heat. You make your choice and you live with it.

 

[thedanl]

For now an average C rate of over ~ 1.5C between 10-80% SoC is not possible unless one is willing to accept accelerated battery degradation. Other than a novel chemistry development, what else can break that barrier ?

My observation is that these 800-900+V pack architectures (I think some even play games to only charge at 800V while the power train is 400V) can sustain a higher average C rate than 1.5. IIRC the Ioniq 5 has demonstrated this capability. According to this inside EVs article, the Ioniq 5 has an average 2.3 C rate from 10-80%, 50% better than 1.5. I think a move to 800+V charging on Teslas could really cut down time on road trips.