Department of Energy - Chademo vs. CCS

[DougWantsALeaf]

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.

[gtleaf]

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.

[DougWantsALeaf]

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/1vwFar3 ... 8DJPh/view

[gtleaf]

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.

[SageBrush]

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]

Even though the EA chargers are listed as 50 kWh chargers, most of them can charge at a higher rate.

[SageBrush]

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.

[gtleaf]

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.

[WetEV]

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.

[SageBrush]

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.