Fast Charging at Electrify America: Lessons learned

[timbop]

...
ou can do the math or look at Tom's charging table:

10-20% took ~5 minutes
70-80% took ~7 minutes
That makes it about 2 minutes faster.

I'm crosschecking ABRP for my trip from NJ to Orlando, and it looks like that chart matches pretty closely to what ABRP calculates for charging times. I'm guessing ABRP must have gotten the charging curve from Ford; a few months ago the charging times changed significantly for the Mach E.

 

[dbsb3233]

Kyle and Tom Moloughney were saying the 150kW+ peak is sustained for longer at a higher SoC. Since you're at 30%, you'd probably know how much of that is true.

I didn't actually time it, but it seemed to be roughly the same 90-120 seconds. It's also a little tricky to keep track of because those silly EA screens keep rotating, and the power level is only on one of the two. And I hate to press the button to return because if you don't get the timing right, you can cancel the session and have to start all over again.

More important was average charging power. While I didn't calculate it for every session, I did for many. I averaged around 95 kW of power. That's not just observation, but pulled from the charging logs by taking the total kWh delivered and dividing by the time duration. My best session averaged 109, 2nd best averaged 108, others were in the 90's or 80's. Only one was below that (way down at 33 kW, where the station obviously had a problem). Adding 40 kWh back in (~110 miles) usually took about 25 minutes of actual charging time.

 

[ChasingCoral]

They spent like 20 minutes discussing the MME charging. They seemed pretty sure that it charges faster starting from 20% than 10%.

I just am curious about the experiences of owners and if folks' sessions mirror InsideEVs.

My experience definitely mirrors what they found. You can watch several of my charging videos at https://www.macheforum.com/site/threads/my-travels-with-marlin-gb-fe-delivered.3298/post-126280

Don't confuse the charge rate at SOC with the initial burst of extra-fast charging. Tom's charging curves are here:
https://www.macheforum.com/site/thr...rify-america-lessons-learned.5989/post-169088

Charge rates at 10% and 20% are the same.

However, the first ~90 seconds will be much faster, with a rate that is independent of SOC. It appears that initial burst will last longer at higher SOC.

 

[BradCA]

Do you think they throttle them?
Both locations I went were huge, 10 and 6 spots and I was alone. I didn’t understand why I was only pulling 30kW on a 150kW plug.

I don’t know what incentive Electrify America would have to throttle its chargers, since EA bills by the kilowatt hour. But I have often wondered if EVgo throttles its machines, especially since it seems they never charge the vehicle at the rate advertised on the machine and because they bill by the minute, not by the kilowatt hour.

 

[BradCA]

I really hope that EA is able to keep up with their charging infrastructure and add stations soon. It's the only type of charger I seek out when traveling because of the fast charging capabilities. I'm a bit worried that they aren't putting in the required O&M to keep them functional and charging at desired rates. Although I've had positive experiences with EA chargers so far, the stations are too few and far between to make me truly comfortable while on a road trip.

I also wonder what will happen during summer months when electrical demand is high in the afternoon; will electric utilities have to limit/throttle electrical draw at these stations to keep the grid stable? If so, that could mean slow charging speeds and long waits.

I agree. They seem to have the most consistent charging speeds at their chargers.

 

[dtbaker61]

I look at this time spent at a charger a little differently and I wish the marketing boys would pick up on it.
...
A lot of this anti-chargeritis is to quell range anxiety issues, but they never say we can charge in the comfort of a dry garage and may never see weather to charge up.

absolutely best to charge at home as much as possible, and even better if you produce your own electricity with PV !

so far 100% of my charging has been at home, on 120vAC overnights; my average miles/day are 20-30 with only the occasional longer day. No road trips over 150 miles yet.

I've been driving an EV since 2008 (see enivrokarma.org if you are curious), powered by PV. This cartoon really says it all to me.... the combination of the EV grin powered with Sunshine, is unbeatable.

I've gotten quite aware of daily trip planning to avoid range anxiety knowing my little DIY conversions only had a range of 40-50 miles max. I find my normal day is <20 miles, and only very occasionally over 100. Now that I have MME, I sold my gas car as that was really only for the occasional work day at a remote site, road trip skiing or camping.

 

[dtbaker61]

I don’t know what incentive Electrify America would have to throttle its chargers, since EA bills by the kilowatt hour. But I have often wondered if EVgo throttles its machines, especially since it seems they never charge the vehicle at the rate advertised on the machine and because they bill by the minute, not by the kilowatt hour.

probably throttled due to capacity of shared transformer. The bigger the transformer, the more expensive.... so they probably were hoping to get by with a transformer that would kick out a total of 100kVa, and it gets shared between charge stations.

 

[Jim Guthry]

These experiences are an embarrassment… I hope the non-Tesla chargers get their shit together if/when the US invests in EV infrastructure this year

 

[dbsb3233]

probably throttled due to capacity of shared transformer. The bigger the transformer, the more expensive.... so they probably were hoping to get by with a transformer that would kick out a total of 100kVa, and it gets shared between charge stations.

Have we heard reports of EA stations splitting power if multiple chargers are in use? I don't think I've heard that. I've had someone using the next charger over and it didn't affect my power. Never been to one with all 4 in use though.

And if the transformers they're installing are too small, I'd hate to see the big ones! Those things are already massive. Sometimes you can see the tops of them inside the fences they enclose them in...

 

[Carsinmyblood]

These experiences are an embarrassment… I hope the non-Tesla chargers get their shit together if/when the US invests in EV infrastructure this year

I'm fairly sure there will be a move to put chargers at large chains, eventually. Charger franchises will begin to pop up and they'll be making deals with NAPA and AutoQuest, chain restaurants like Cracker Barrel and hotel/motel chains. Grants in remote areas and financial help in others is coming.

It'll ba a challenge for some of these on pad sites (a NAPA renting the land upon which they build their own building). The landlord may be looking for a piece of the action. There can be localized power limitations..... etc.

But, it's coming. D.C. knows it. Detroit knows it, a OPEC knows it.

 

[rhougey]

New BEV owner here. I've replaced my 2017 Volt Premier with a new MME Premium Extended RWD two weeks ago today. On Monday we will be making our maiden voyage to our second home 235 miles north between Lake Shasta and Mt. Shasta, almost entirely at 75 mph. It's a round trip we make a couple times a month. With an EPA rated range of 300, I am having a bit of range anxiety. I know where we can stop (ElectrifyAmerica) if necessary for a KW bump both directions. It is my hope that we will find we can usually make the trip without topping off , even if I have to slow down a bit. We will see, I guess.

 

[dbsb3233]

New BEV owner here. I've replaced my 2017 Volt Premier with a new MME Premium Extended RWD two weeks ago today. On Monday we will be making our maiden voyage to our second home 235 miles north between Lake Shasta and Mt. Shasta, almost entirely at 75 mph. It's a round trip we make a couple times a month. With an EPA rated range of 300, I am having a bit of range anxiety. I know where we can stop (ElectrifyAmerica) if necessary for a KW bump both directions. It is my hope that we will find we can usually make the trip without topping off , even if I have to slow down a bit. We will see, I guess.

You'll probably be OK making it 235 miles in the RWD ER from 100% if the weather is decent (dry roads, no severe wind, temps 50F+). But... for the first attempt I'd definitely stop to top off at EA if it's along the way. Track your arrival miles/kWh (MPK) on each leg. Then you can easily calculate how you would have done without stopping to top off. That'll give you a good idea for the future trips.

I recently got an average of 2.6 MPK in my AWD ER through CO/UT/NV, so probably similar conditions to what you'll see. But the RWD is 10% better so I'd expect maybe 2.9 MPK. If starting at 100% and arriving no worse than 10%, that's 90% of the 88 kWh battery = 79 kWh * 2.9 = 229 miles. So it could be close. You might get better than 2.9, but that's roughly what I'd expect at 75 MPH with climate control on.

Also note any significant elevation differential. If you're coming from sea level and gaining like 3500' up to Shasta, that could cost as much as 20% more (but gain it the other way). You may find you can go downhill the whole way comfortably but not uphill.

 

[macchiaz-o]

And if the transformers they're installing are too small, I'd hate to see the big ones! Those things are already massive. Sometimes you can see the tops of them inside the fences they enclose them in...

Out here they don't bother to fence them in.

 

[mdolan92869]

Out here they don't bother to fence them in.

Oh give me a home,
where the transformers roam,
and the electrons and protons play,
where seldom is heard,
an exhaust pipe word,
and the skies are not cloudy or gray.

 

[dbsb3233]

Oh give me a home,
where the transformers roam,
and the electrons and protons play,
where seldom is heard,
an exhaust pipe word,
and the skies are not cloudy or gray.

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