QC Charging Study - Nissan vs EA vs EVgo vs Chargepoint

We often read reports and watch videos about various types of range test for the Nissan Leaf. While all of them are very informative, there does seem to be one area lacking in research. The QC station or network itself. While we assume that all QC are equal, from what I've seen, many are not. Often, they can even be a bottleneck to charging when a station claims to provide 50 kW of power (or 100 kW for others) and it seems as though they struggle to even output that much power. It then shifts the blame onto the EV itself asking "why isn't it charging faster". For those familiar with the Nissan Leaf, charging power can vary because of pack temperature, battery age, etc. I've read and watched many reviews about "range testing" the Leaf (and Ariya) where it is often blamed on the EV for slow charging times. While we can often blame the EV for being slow to charge, this only works in identical circumstances. I want to bring in more info to this subject by using my unique circumstance to test all the charging networks against each other. While I can post all about my anecdotal experiences with all the charge networks, I think having some read data to back it up with go further to helping us all understand the quirks of quick charging the Leaf (and other EV by extension)

As I gather more data, I'm going to post it up here in this topic. Such as battery temperature, state of charge, outside temperature, charging network used, LeafSpy graphs, etc. This way, we can all come up with our own conclusions about what variable effect the QC network has on long range testing of EV charging times.

Awesome. Thank you in advance. Please let the group know if you need more data points. Just provide which ststion, battery temp, starting and stopping SoC, etc.. as well as metrics you want collected.

To make it more "apples to apples" comparison, I'm going to try to keep all the charging to a semi-standard.

Try to keep the battery temperature the same for every station. The weather should help me with that, means I can do probably do at least one test per day since it's easier to drive out in the early morning when the battery is cooled down, low chance of someone else doing a QC in the early morning, etc.

I'm going to try to always start at the same SoC, like 20% and see how long it takes to reach 90%. As much as I would like to see how long it takes to reach 100%, most of the QC won't even do that due to time restrictions. I've ever only seen EA hit 100%, the others tend to stop at 95%, 96%, or 98%, etc. so it's not very precise or consistent to muddy up the data that way. 90% is easy to stop at for all of them.

Finally, LeafSpy graph everything. So it has everything, temperature of battery, how much charging power, etc. all in one graph so it's easy to do a comparison, plus I'll be manually tracking stuff in a spreadsheet as a backup (charging time, max power, min power, outside temperature, etc)

It will be a slow trickle of data, but should be interesting to see a more detailed comparison between them all. Granted, this is only in my area, so this means an EA station that does great here might do poorly elsewhere and vice-versa for EVgo, Chargepoint, etc. At least thought it's a starting point if others want to take time to document their experience.

I suggest taking a photo of the nameplate for each location you visit, and check plugshare for reports of working but possibly defective chargers.

I don't really see the point of this exercise but I hope you have a good time.

SageBrush said:

I suggest taking a photo of the nameplate for each location you visit, and check plugshare for reports of working but possibly defective chargers.

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Good idea. I do use plugshare a lot, but I've never seen people complain much about the charging power, more about "doesn't work" "works fine" is about as good of feedback I see in my area. :lol:

I don't really see the point of this exercise but I hope you have a good time.

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Actually, I feel the same way in the grand scheme of things because the QC station in my small area in no way reflects all of them across the nation, but I feel that knowing that a difference can exist is important when it comes to defining what is working properly on an EV and what is not. If everyone that pulls up to an EA QC is getting 50 kW and you pull in and only get 25 kW, at least it helps in trying to figure out if your EV is the problem or is the QC doing something wrong.

Some of these probs might apply to CHAdeMO plugs:
https://www.greencarreports.com/news/1131501_2021-volkswagen-id-4-range-and-road-trip-charging-some-first-impressions - search for 32 kw and thermal

Some sites have some station or plugs that give apparently low output, sometimes.

Example https://www.plugshare.com/location/321832 - besides some people not knowing their units, one guy on Oct 8, 2022 said:

Oct 8, 2022
...
Tesla Model 3 54 Kilowatts
Anemic charging on all units. Was charging at 12Kw on the one closest to the road, moved to the other chargers and am getting 45kW. The best all vehicles here are seeing at present is 85kW. Use station #1 if it is open.

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From Oct 6:

Kia EV6 2022
50 Kilowatts
Station 1 is a 150 and they are getting 70
Station 2 is a 350 and I'm getting 50
Station 3 is a 350 and they are getting 45

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I've seen reports like these by browsing Plugshare's activity feed quite frequently. And yes, some people have hit similar probs on Tesla Supercharger sites, per Plugshare reports.

knightmb said:

I feel that knowing that a difference can exist is important when it comes to defining what is working properly on an EV and what is not.

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Fair enough, but the lion's share of "charging problems" are explained by pack temperature and/or SoC. I've learned that even among EV drivers there is a huge information gap between the middle 75th percentile and what you know. You are not chasing phantoms, but the elephants in the room are chuckling.

The other issue relevant to your study is that a LEAF may not be enough demand on a 300 Amp charger to bring out differences. I've read that problem #1 for DC chargers is lack of maintenance (read: cleaning) that impairs cooling. 75 kW is only 4/9ths the heating load that a 150 kW charger was designed for.

SageBrush said:

knightmb said:

I feel that knowing that a difference can exist is important when it comes to defining what is working properly on an EV and what is not.

Click to expand...

Fair enough, but the lion's share of "charging problems" are explained by pack temperature and/or SoC. I've learned that even among EV drivers there is a huge information gap between the middle 75th percentile and what you know. You are not chasing phantoms, but the elephants in the room are chuckling.

The other issue relevant to your study is that a LEAF may not be enough demand on a 300 Amp charger to bring out differences. I've read that problem #1 for DC chargers is lack of maintenance (read: cleaning) that impairs cooling. 75 kW is only 4/9ths the heating load that a 150 kW charger was designed for.

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Oh, this topic isn't meant to be positive spin for those charging networks, it's meant to be a "yeah, this sucks and see how bad".

First Test (and Failure :lol: ) today.

QC Network: Nissan HQ - QC
Date: 10/14/2022
Outside Temp. 68 F (20 C)
Cost: $0.00
QC Session Time: 19 Minutes
Max kW: 78 kW
Min kW: 46 kW
SoC Start: 21%
Soc Stop: 64%
Battery Temp. Start: 68 F (20 C)
Battery Temp. Stop: 91F (33 C)

Notes: QC session was stopped early because QC station over-heated. (known issue to happen at random there)
Charge Power Didn't drop below 50 kW until 60% SoC

Conclusion: Knew ahead of time of QC doing random session drops, but was surprised it happened during cool weather. Knew something was up with the QC when I saw those sudden drops in charging power. Usually when using a 100 kW ChaDeMo, the ramp up to full power and ramp down is very smooth (on my Leaf, can't speak to others). QC Station fans kicked into super-high mode right before session failure.




[edit: Forgot to add pictures of charger and plate]

IIRC, the most common issue with those Chademo DCFC stations is the filter for the air cooling system blocking up with dirt from lack of maintenance. That would produce excessive heating in all but maybe frigid ambient temps.

LeftieBiker said:

IIRC, the most common issue with those Chademo DCFC stations is the filter for the air cooling system blocking up with dirt from lack of maintenance. That would produce excessive heating in all but maybe frigid ambient temps.

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The QC sit under trees, so yeah, looking at the side, it is certainly full of debris. :lol:

QC Network: Electrify America
Date: 10/15/2022
Outside Temp. 69 F (20 C)
Cost: $9.76
QC Session Time: 61 Minutes
Max kW: 46 kW
Min kW: 11 kW
SoC Start: 19%
Soc Stop: 90%
Battery Temp. Start: 69 F (20 C)
Battery Temp. Stop: 98F (36 C)

Notes: No issues during entire session. Charge power was 32 kW @ 80% SoC

Conclusion: Compared to other EA QC I have used, this one is the slowest. Mainly because others I've used can hold 20 kW of charging power all the way to 100%, this one was down to 11 kW by 90% SoC. Could be my Leaf of course, but other's I've used don't do this and I've charged on much hotter days than today.

Great first data point.

DougWantsALeaf said:

Great first data point.

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Yeah, I wish my first one was better, but I'll come back to Nissan HQ again after I make it through EVgo and Chargepoint, I'll just cycle between them all over and over to get more data points as I have time and weather permits.

Interesting reading the ratings sticker on the "charger". It looks like all the power conversion electronics is back in the "power bank", as the output specifications are the same as the DC input specifications. The 277 VAC is just one phase to neutral of the 480V phase to phase that would power the power bank. 15A allows for a generous (!) 4kW for the computer, screen, lights,,, :shock: I guess 15A is the smallest fuse that they deal with.

So a site with say 8 "chargers" or "charging stations" in reality probably only has one or two "power banks". There must one power converter for each station, since each vehicle is probably at a different voltage. So one or two rectifiers would be supplying all these power converters. My guess is that the rectifier(s) is(are) way lower power than needed to supply each charging station with 150kW. So if a lot of vehicles are charging, it must drop the power to all chargers.

You would think that it would drop the power to chargers equally, so no charging station should be slower than others.

Since EA was brought up, keep in mind they have 4 different suppliers which https://insideevs.com/news/389891/exclusive-interview-electrify-america-problems-solutions/ mentions: BTC Power (two different styles now), ABB, Signet (2 different styles) and Efacec.

On Oct 15, knightmb used a style of EA Signet I've never personally seen before but I know exists. From https://www.chevybolt.org/threads/dcfc-reliability-%E2%80%93-an-open-letter-to-electrify-america.34849/#post-533232, the pics show from left to right: BTC Power, ABB, Efacec (I've never seen these nor used these), Signet "v1".

https://www.plugshare.com/location/296759 is an example of Signet "v2". This is the only EA Signet style I've personally seen and used (numerous times, at that).

https://teslamotorsclub.com/tmc/threads/electrify-america-general-discussion.249553/page-22#post-6867023 has one of EA's next generation chargers. Don't know if BTC Power is the only supplier of those. Doubtful any of those will have CHAdeMO.

https://www.chevybolt.org/threads/my-informal-tour-of-an-electrify-america-station-in-california.35822/ is a "tour" of EA ABB equipment.

QC Network: EVgo
Date: 10/16/2022
Outside Temp. 72 F (22 C)
Cost: $11.19 - ($0.99 Session Fee + $0.34 / minute) - Pay as you Go Plan
QC Session Time: 30 Minutes
Max kW: 35 kW
Min kW: 35 kW
SoC Start: 20%
Soc Stop: 59%
Battery Temp. Start: 72 F (22 C)
Battery Temp. Stop: 86F (30 C)

Notes: No issues during entire session. Sessions are limited 30 minutes no matter what!?

Conclusion: By far, the slowest QC charger. I did learn something today though, it seems ChaDeMo does have something in the protocol to communicate to the car "when" your charging session will end and it shows up on the display as an estimate of how much battery charge you will get in that limited amount of time. Never knew the Leaf could do that, very interesting.

QC Network: Chargepoint
Date: 10/17/2022
Outside Temp. 62 F (16 C)
Cost: $5.00
QC Session Time: 55 Minutes
Max kW: 46 kW
Min kW: 24 kW
SoC Start: 23%
Soc Stop: 90%
Battery Temp. Start: 67 F (19 C)
Battery Temp. Stop: 94F (34 C)

Notes: No issues during entire session. There were no plates to take a picture of the electrical specs like the others. The closer QC station was offline, so I had to drive a bit further to get to this one, thus, I couldn't predict what starting SoC I would arrive at and the battery got a little warmer from the drive too; since it was not within a few miles away.

Conclusion: This is the fastest QC so far (not counting Nissan QC, which didn't finish a full session the first time). The QC is rated for 62.5 kW but as you can see, it could only reach 46 kW Tops. Why would I rate this one the fastest? Not because of Max KW but because of the power it was able to hold while even at 90% SoC, as you can see, it was still holding 24 kW. I have no doubt it would hold at least 20 kW all the way to 100% like some Nissan and EA chargers I've seen in the past.

I've noticed at several EA stations that the individual chargers are often rated for 350kW, but the signs on the chargers and web info say that some are 150kW and others 350kW. Saw this today while charging at a EA BTC charger; max output 350kW, but the charger sticker under the connector (see EA charger photo upthread) said 150kW. I assume it's cheaper to use a single model of charger, and just limit the max. output as needed.

QC Network: Nissan HQ ( 2nd Try! )
Date: 10/18/2022
Outside Temp. 48 F (9 C)
Cost: $0.00
QC Session Time: 45 Minutes
Max kW: 79 kW
Min kW: 17 kW
SoC Start: 29%
Soc Stop: 90%
Battery Temp. Start: 56 F (13 C)
Battery Temp. Stop: 84 F (29 C)

Notes: No issues during entire session. I started at a higher SoC because I didn't know if the QC was going to overheat and fail again, but the weather outside was very cold, relative to a few days ago. I figured that would help it out a little. Pleasant surprise, was able to do a full session. Power didn't drop below 50 kW until 57% SoC, power at 80% SoC was 34 kW.

Conclusion: When it can complete a full session, the QC at Nissan HQ are the fastest because they output the most power (when not over-heating :lol: ) As mentioned earlier in this topic, they need to do some maintenance on their QC stations (actually, all that I tested probably do). If I could find another charging network that could match Nissan HQ for power, then I think charging times could come down even further given a QC that is in top working condition. Don't blame your Leaf if the QC charging is slow, seems to be more likely an issue with the QC station itself than the Leaf. :?