Department of Energy - Chademo vs. CCS

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Aside from the relative counts between Chademo and CCS, the AFDC website has, in my humble opinion, a flaw in the way that they count stations.

Take this station near where I live in San Diego....

https://afdc.energy.gov/fuels/electricity_locations.html#/station/93121

They show 4 Chademo and CCS outlets, but those are the typical ABB stations that have 2 cords and can charge only a single car.

So they have two DC Fast chargers that can charge either flavor, but can still only charge two cars at once. By stating they have 4 outlets, i think they are overstating the count of what is really there...

This would also be true for EA stations.

One being built nearby me has three charger boxes and three dispensers with dual cords. #1 has two CCS 150 kW, #2 has two CCS 150 kW, and #3 has 1 CCS 150 kW and one Chademo 50 kW cord. Do you count that as 5 CCS and 1 Chademo? That isn't really correct since only three cars can charge at once...
 
Nubo said:
SageBrush said:
...I'll be delighted if all parties can reach 200 Amps but more incompatibilities cropping up seems more likely. And that is the Achilles's heel of CHAdeMO -- it has not proved to be reliable outside of the certification laboratory.

What is the typical failure mode of a CHAdeMO station? Is it a fault of the specification or just crappy implementation?
Interesting question -- I don't know.
The EA debacle smells more like a less than robust spec but that is just a guess.
And the high failure rate could be manufacturer related.

Or just go for all three :lol:
If CHAdeMO was a successful protocol money would probably fix these issues but since it is in ~ caretaker mode problems fester, stations remain out of commission indefinitely, and progress is shoddy.
 
Randy said:
Aside from the relative counts between Chademo and CCS, the AFDC website has, in my humble opinion, a fatal flaw in the way that they count stations.

Take this station near where I live in San Diego....

https://afdc.energy.gov/fuels/electricity_locations.html#/station/93121

They show 4 Chademo and CCS outlets, but those are the typical ABB stations that have 2 cords and can charge only a single car.

So they have two DC Fast chargers that can charge either flavor, but can still only charge two cars at once. By stating they have 4 outlets, i think they are overstating the count of what is really there...

This would also be true for EA stations.

One being built nearby me has three charger boxes and three dispensers with dual cords. #1 has two CCS 150 kW, #2 has two CCS 150 kW, and #3 has 1 CCS 150 kW and one Chademo 50 kW cord. Do you count that as 5 CCS and 1 Chademo? That isn't really correct since only three cars can charge at once...

Good point.
How then do you count CHAdeMO ?
1/2 ?
None ?
 
Fair enough, I'm not sure whether it is the Leaf or the EVgo charger that started dialing back the charge rate when the battery was only half full. When you look at Nissan's website, they seem to indicate you could get about 80% charge in about an hour but I don't see that being realistic if I only got about 40% after 45 minutes. I agree though, not a great road trip car if you need to charge it along the way. I drove about 180 miles to my destination so I didn't have to rely on charging to reach my destination. This was more of an experiment, I didn't buy my Leaf thinking it would be a road trip car.
 
gtleaf said:
Fair enough, I'm not sure whether it is the Leaf or the EVgo charger that started dialing back the charge rate when the battery was only half full. When you look at Nissan's website, they seem to indicate you could get about 80% charge in about an hour but I don't see that being realistic if I only got about 40% after 45 minutes. I agree though, not a great road trip car if you need to charge it along the way. I drove about 180 miles to my destination so I didn't have to rely on charging to reach my destination. This was more of an experiment, I didn't buy my Leaf thinking it would be a road trip car.
All car batteries taper charge as they fill up, although the details differ.

A useful way to compare different cars is to compare C rates:
If the battery is X kWh capacity, then X kW is 1 C

E.g., my Tesla Model 3 can charge at ~ 3C for a short time between 10-20% SoC
Then it charges at 2.5C for the next 20%
At 45% SoC it tapers down to ~ 2C until 55%
By 60% SoC it is charging at 1.5C and the taper continues from then on...

Like so:

uc
 
GLeaf

On my Iowa trip last month, I charged from 16% to mid 70's in about 42 minutes at an EA charger (in spite of high battery temps), so I think the Plus is pretty close to advertised if the charger has the power. The EA charger was giving me 53-54 KW, for the main part of the battery charge, then tapered until I took it off at 90% (it has reduced to 20 KW by then).

When the new 150 KW Chademo chargers get installed, I am eager to see whether the Leaf can hit a 100KW peak pull.
 
DougWantsALeaf said:
When the new 150 KW Chademo chargers get installed, I am eager to see whether the Leaf can hit a 100KW peak pull.
EA has installed 200 Amp CHAdeMO although it has been derated to 125 Amps for now due to unspecified problems.

At 200 Amps your peak power into the battery would be ~ 72 kW, presuming the car can take it (40 kWh LEAF I'm not sure; 62 kWh LEAF presumably yes .... unless rapid-gate trumps)
 
Nubo said:
SageBrush said:
...I'll be delighted if all parties can reach 200 Amps but more incompatibilities cropping up seems more likely. And that is the Achilles's heel of CHAdeMO -- it has not proved to be reliable outside of the certification laboratory.

What is the typical failure mode of a CHAdeMO station? Is it a fault of the specification or just crappy implementation?

As I understand it, the typical failure mode, at least for older stations, is overheating due to clogged air intake filters that weren't serviced regularly. There may be other issues with newer stations.
 
It definitely makes sense that the charge would taper off some as the battery fills up, just was surprised to see it go from 35KW down to 20KW after only 50%.

That's good info to know on your Leaf Plus experience, I'm glad to hear it is the charger and not my car. This was a business trip, so I'll see if there are any other CHAdeMO stations in the area I can try the next time I go.
 
I have been using quick chargers frequently the last couple of years first due to frequent long trips across the Phoenix metro area and now due to battery capacity loss (gradual loss until recently with a few weak cells causing greatly reduced range now). I use both EVgo (combination CHADeMO and CCS) and Blink (old CHADeMO units with 2 cables). Both brands will only charge one car at a time. I prefer the Blink units because they have a bit higher output, don't stop after 30 minutes, and cost less per charge (with memberships in both networks). I have also noticed broken handle latches on the EVgo CCS cables on numerous occasions so I am concerned about the safety/reliability of those connectors. The CHADeMO connectors are heavy duty connectors similar to high-current welding receptacles/plugs while the CCS connectors are just L2 connectors with two additional terminals for DC current. Since LEAF is the only car still available in the USA with CHADeMO connector, I suspect those chargers will gradually fade away so I am starting to consider replacing my 2015 with a longer-range car to eliminate my need to use quick charging.
 
I agree that Nissan and Mitsubishi alone not are likely to hold the Chademo Fort for too many years. Having All the Tesla’s now potentially having access may give the connector a bit more life. If Leaf sales go up and they Launch a few more higher volume models, that would help too. Toyota is the other variable. The prime carries a Chademo, but not yet on the US version.

All That said, the number of Chademo stations is still going up pretty rapidly. A good chunk of those are EA, but not nearly all of them. The desire is to see more 2 nozzle stations over the single EA stops.

If the new China cars next year start using Chademo or Chaoji its a whole new ballgame as that standard goes up to a potential 900KW.
If Tesla sells its supercharger network or even access to it, that also changes the calculus quickly.

Chademo will be fine for next 3 years though surpassed by ccs in the next year in terms of total stations.
 
I've tried a couple more quick chargers and it looks like the EVgo one I mentioned earlier just tapered off on it's own. I used a free quick charger that supplied 30KW and it charged my Leaf at a fairly consistent 30KW all the way from 25% to 90%. I also used an Electrify America charger that supplied 44KW from 60% to 75%, then tapered off to about 28KW when I stopped at 90%. It would seem the EVgo charger backed off on it's own, I would assume because it was charging by the minute.

Anyone know why all the pay chargers charge by the minute instead of by the KW? It would seem this method incentivizes them to charge at a lower rate than the car can except to increase their profit.
 
Many states don’t allow charging by KW unless you are a utility. So by minute is what companies end up using.

Last night I peaked at 73 kWh on a new charger in my area.

07/28/2019 08:57:49 PM
Lincolnwood Town Center
3333 W Touhy Ave.
Lincolnwood, Illinois 60712
Charger #200014-01
Connector #2
Total paid: $6.07
Session ID: 35142
End state of charge: 50%
Total energy delivered: 22.1 kWh
Max charging rate: 73.29 kW
Charging time: 00:20:17
Grace period: 00:10 min
Paid idle time: 00:00

https://drive.google.com/file/d/1vwFar3npeDc-tMLMkveRR14qoNY8DJPh/view
 
Wow, that's impressive! The Electrify America charger I tried was brand new, it just opened a week or two ago. Unfortunately, it is only a 50KW charger.
 
EA has kW tiers, and then charges by the minute.
Some charge by the kWh
No one charges simply by the 'kW' -- learn your units, LEAF owners !
 
DougWantsALeaf said:
Even though the EA chargers are listed as 50 kWh chargers, most of them can charge at a higher rate.
listed as 50 kW chargers ...

kW is a rate
kWh is an amount

The units confuse many people because a watt is a joule per second. You are looking for the 'per second' part of the unit but it is hidden in the watt term. See why kWh is an amount ? It is watt * time = (joule per time) * time. The time cancels out and joules (energy) remain.
 
I'm well aware of the difference, I'm an electrical engineer. You got me on the notation though, kW is more correct than KW but I think you know what I meant. So, my 62 kWh battery was being charged at a 44 kW rate at the beginning and tapered off to 28 kW at the end, we cool? ;)

Seriously though, I have limited experience with the quick chargers at this point but find it interesting that the commercial ones that charge by the minute gradually reduce their rate but the free one I tried did not. I do know how batteries work and that the power has to taper off at some point as the battery fills up. However, my experience to date is showing that the commercial chargers are backing off before they need to.
 
gtleaf said:
Seriously though, I have limited experience with the quick chargers at this point but find it interesting that the commercial ones that charge by the minute gradually reduce their rate but the free one I tried did not. I do know how batteries work and that the power has to taper off at some point as the battery fills up. However, my experience to date is showing that the commercial chargers are backing off before they need to.

The car tells the external charger what current to supply.
 
gtleaf said:
Seriously though, I have limited experience with the quick chargers at this point but find it interesting that the commercial ones that charge by the minute gradually reduce their rate but the free one I tried did not. I do know how batteries work and that the power has to taper off at some point as the battery fills up. However, my experience to date is showing that the commercial chargers are backing off before they need to.
It goes by car manufacturer, cell chemistry, and C rate. If you found a charger that did not taper it only means that the peak power was low.
 
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