NJDevFan30

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We had a road trip planned and happened to take delivery of our extended range, RWD MME 2 weeks beforehand. Now or never... we dove head first and packed up the car, our 4 year old daughter, 2 year old son, and dog and headed from NJ to St. Louis.

For those who like to delve into the data and numbers I wanted to start this thread in hopes you could teach me a thing or two about some oddities related to charging.

Before I get to that, the car and the trip were/are amazing. There was ample room in the back seat for two young kids, our dog, and more than enough toys to (attempt to) keep our kids entertained. The frunk and below floor storage in the rear gave us much needed storage for extra items leaving the trunk for our luggage and items we needed easy access to. The car was a gem to drive and got lots of attention on the road and at DCFCs. As many before have stated, this car is such a joy to drive. Are there some quirks... definitely, but nothing that made us regret the purchase or taking it on our adventure.

Now on to the purpose of this thread.

Observations and Questions:
1. On about half my charge sessions when I plugged in, the DCFC would charge but max out at +/- 33kW or ramp up to high speed but only for a few minutes and then drop down to about 33 kW. This was not an 80% charge cliff issue. The car was often only at 20% SoC or less. Solution: I would unplug, switch bays and then it would ramp up to 110-120 kW. This was definitely not a one off and not a coincidence, it happened multiple times at multiple EA stations. 110-120 speed seemed to be the most consistent max. draw I would pull. Is this an issue with the MME (what it is calling for) or with EA's DCFCs?

2. A few EA bays wouldn't activate. Solution: Switched bays and then no problem.

3. At one EA station both on the trip out and the trip home (different stations), EA charged (kWh) the car but there was some error and didn't charge me ($). No complaints.

4. After using up my Plug & Charge allowance and deactivating to use EA's Pass+ rate I noticed two times the EA app was showing power of 200+ kW whereas the DCFC console was showing a more realistic charge rate. Obviously the 200+ was wrong but it makes me skeptical to leave the car charging by itself and rely on the EA app.

5. In PA, the EA stations were $/min, $0.24 for Pass+. If you do the math, charging is so cheap if you can keep even a modest charge rate. The cost per kWh was on par with charging from home. I wish I realized this earlier and deactivated Plug & Charge on our way out to STL. Save your credits for $/kWh stations.

6. At the two $/min EA stations we stopped at, our charge speeds were well above any of the other $/kWh stations. We maxed out near 157 and stayed at a higher charge rate far longer. I'm not sure if this was coincidence, a result of similar conditions (they were back-to-back on the same day), or what but it was a pleasant surprise from the previous speeds were getting (note 1 above).

7. Be leery of the 'Trip' screen data.
  • Prior to our trip I reset 'Trip 1' intending to use this to track our trip. After leg 1 (220 miles, 95 degree heat, 75 MPH highway driving) it was reporting 3.9 mi/kWh. Amazing! Not so fast. If I did the math myself (see notes below and the attached chart) I was getting closer to 3.0 mi/kWH. I hadn't noticed previously but my 'Trip 1' mi/kWh was (and remains) identical to my 'Trip 2' value, which has been tracking the lifetime of my driving. The data provided is just wrong! All the posts about ignoring the GOM (yes I know) and instead multiplying your mi/kWh x battery pack (in my case 88) have no value if the car is not reporting accurate mi/kWh. Has anyone else had this issue with 'Trip 1' showing the same efficiency as 'Trip 2?'
  • Times are inaccurate. As others have suggested it seems to restart at 24 Hrs and not keep track of days, but I couldn't validate that.
  • I abandoned using 'Trip 1' for the trip out to STL. On the trip home I tried to be diligent about capturing the data on 'This Trip' for each leg before I shut the car off and those values seemed to be more accurate.
  • 'This Trip': Anyone figure out what causes 'This Trip' to reset to 0? Most of the time when you turn the car on it does but there were plenty of times where multiple stop-and-start cycles would track on the same trip. It's not based on a home or charging location either. Tried out that theory. Seems to be random.
8. DCFC-ing was a really nice break every few hours on a long road trip, especially with little kids. Not once did we feel like we were sitting around waiting for the car to finish charging. It was a good time for meals, to stretch our legs, and for the kids to play. It's nice that most of the Walmart EA stations are in the back corner of a parking lot. (Maybe one of you found our kids' chalk art.) We met plenty of folks who just wanted to chat about the car and few who did a stealth drive by photoshoot.

See attached for a log I kept to keep track of mileage, SoC, charge sessions, etc. I couldn't figure out how to upload the actual Excel file.
  • Column numbers (top row has the numbers) 1-5 provide basic info on mileage and SoC
  • Columns 6-8 provide info on energy consumption using some basic calculations based on the SoC change and mileage for each leg, along with what the 'Trip Screen' reported for mi/kWh
  • Columns 9-17 have info on the charge session including both kWh reported by the EVSE as well as calculated based on the SoC change multiplied by an 88 kWh usable battery

9. Energy Usage and Efficiency (Columns 6, 7): Based on the SoC change multiplied by an 88 kW usable battery I calculated out how much energy was used each leg and the mi/kWh based on the odometer reading. I used this for comparison to the 'Trips' mi/kWh (see point 6 above). Note: On the trip home using the 'This Trip' screen the mi/kWh were all within 0.1 mi/kWh which I can chalk up to rounding.

10. Energy Usage, Calculated vs Charger Reported (Columns 11-13): Note that the EVSE reported a difference of between -9% less and up to 14% more kWh compared to a calculation of SoC change multiplied by the battery pack.
  • Negative values were all on small charges so I assume that's a rounding issue.
  • EA stations pretty consistently reported +/- 5% more kWh than a SoC calculation. Is this typical efficiency loss?
  • The 14% was a free ChargePoint station. Not sure what the deal is with that one.
11. If any of my assumptions or calculations are incorrect , feedback is appreciated. I wish the car would visualize some of this for us.

Closing Notes:
  • Have some patience with Electrify America stations. All of our charge sessions worked out fine, but they often took a bit of troubleshooting and reconnecting.
  • Plug & Charge worked well.
  • $/min DCFCs are so cheap if you can maintain a decent charge speed! Do the math and save your Plug & Charge kWh for $/kWh stations.
  • Expect charge speeds to be below the 150kW advertised max. for the car. The majority of the charging was well below this.
  • Ford should provide better logs, historical data, and infographics on the efficiency and battery usage of the car. It's virtually non-existent other than the 'Trips' screen mi/kWh which I've lost faith in (see point 7 above). I would love to be able to see efficiency logs/graphics, charge curves, etc. built into the UI.
  • I only saw one other MME our entire trip and it was at an EA station in Ohio. Ironically we were both Infinite Blue, extended range, RWD. He was a Buckeye fan and I'm a Penn Stater so we'll let that bit of poor judgement slide.

For those who got through this long post, I give you credit. For those who may have feedback, similar or different experiences, chime in.

The car is a winner and this road trip proved it to us.
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ncaadam

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First off, fantastic write up! This type of information and hard data is great to see. Thank you for doing it.

Prior to our trip I reset 'Trip 1' intending to use this to track our trip. After leg 1 (220 miles, 95 degree heat, 75 MPH highway driving) it was reporting 3.9 mi/kWh. Amazing! Not so fast. If I did the math myself (see notes below and the attached chart) I was getting closer to 3.0 mi/kWH. I hadn't noticed previously but my 'Trip 1' mi/kWh was (and remains) identical to my 'Trip 2' value, which has been tracking the lifetime of my driving. The data provided is just wrong! All the posts about ignoring the GOM (yes I know) and instead multiplying your mi/kWh x battery pack (in my case 88) have no value if the car is not reporting accurate mi/kWh. Has anyone else had this issue with 'Trip 1' showing the same efficiency as 'Trip 2?'
Yea, 3.9 is far too high given those parameters and based on my experience. I haven't noticed my efficiency being seemingly too far off of what i expect. However, as you mentioned, this may be specific to a Trip 1/2 page.

1. On about half my charge sessions when I plugged in, the DCFC would charge but max out at +/- 33kW or ramp up to high speed but only for a few minutes and then drop down to about 33 kW. This was not an 80% charge cliff issue. The car was often only at 20% SoC or less. Solution: I would unplug, switch bays and then it would ramp up to 110-120kWh. This was definitely not a one off and not a coincidence, it happened multiple times at multiple EA stations. 110-120 speed seemed to be the most consistent max. draw I would pull. Is this an issue with the MME (what it is calling for) or with EA's DCFCs?
I think the 33kW is the default output when the EA charger doesn't know what to do. I'm not sure if it is an EA problem or a MME problem. I'd lean toward an EA charger problem because I have the same experience from you: if i switch bays or even just chargers at the same bay, things go back to normal. I'm sure others here can shed some more light on this issue.

I've shared the below charge curve on other parts of the forum. I have it saved on my phone for reference. I'll share it here in case you haven't seen it before.
1631288824414.png


  • Ford should provide better logs, historical data, and infographics on the efficiency and battery usage of the car. It's virtually non-existent other than the 'Trips' screen mi/kWh which I've lost faith in (see point 7 above). I would love to be able to see efficiency logs/graphics, charge curves, etc. built into the UI.
i completely agree with this. luckily, this data is readily available in the car. i've seen some good stuff on this forum actually. fingers crossed they actually develop something for us 😏
 

phidauex

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10. Energy Usage, Calculated vs Charger Reported (Columns 11-13): Note that the EVSE reported a difference of between -9% less and up to 14% more kWh compared to a calculation of SoC change multiplied by the battery pack.
  • Negative values were all on small charges so I assume that's a rounding issue.
  • EA stations pretty consistently reported +/- 5% more kWh than a SoC calculation. Is this typical efficiency loss?
Great data, thanks! Always good to see some real results rather than just anecdotes or impressions.

As far as the ~5% charging losses that sounds about right and totally plausible. Based on the internal resistance of the battery (which I measured to be around 36 mOhms on my ER), your losses in the battery itself during DCFC would be 2.6% to 3.8% if you are between 100kW and 150kW charge speed. Assuming that you'd have a similar amount of additional losses from the cables and distribution system, as well as about another 1% to run your AC and loads in the car, and landing between 5-6% total losses from point of delivery to actual charge is reasonable, and actually pretty darn good.
 

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Agreed, nice write up. Comments I have:
  • While Ford states the "peak" rate of 150kw, as you saw that is only breiefly at best. If you look at their statements about how long it takes to DCFC from 20% to 80% you realize that the average is closer to 110kw. It's misleading on Ford's part, and shame on them
  • Yes, resetting the trip1 or trip2 can sometimes "freeze" the displayed value for mi/kwh. If you hit reset and it doesn't change the displayed value to 99.9 you have to hit it again until it does display 99.9 or else the value displayed is "stuck"
  • That is really interesting that the P&C and fordpass charging often resulted in 33kw but using the EA app did not. That almost sounds like an authentication/timeout situation wherein there is a short window for the car and station to negotiate the max charge level and the backend server process for authentication eats too much of that negotiation time so it defaults to 33
  • Thanks for taking the time to share all of this; it's good data and good to know you had such a positive experience
 
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NJDevFan30

NJDevFan30

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I've shared the below charge curve on other parts of the forum. I have it saved on my phone for reference. I'll share it here in case you haven't seen it before.
1631288824414.png
Thanks for sharing! I had not stumbled upon that before but it looks to be right on what I saw on most charges, 110-120 kW start followed by a drop to the 70s.

Happen to know if there's a RWD version, if there's much of a difference?
 

ncaadam

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Happen to know if there's a RWD version, if there's much of a difference?
i'm unsure. i think the curves vary between extended and standard range, but maybe not between trims. someone here can chime in if they understand something different.
 

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Good info. Did you track speed? On our trip down to FL, we were driving 74 or more most of the time. My roughly calculated m/kwh is 2.88. If you were driving slower, that might explain your higher numbers.

Good point about using the free charging in the per kWh states instead of the per minute states. Probably should have done that. Oops.
 

timbop

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Oh, I forgot one thing: the displayed mi/kwh also displays in "bands" instead of simple rounding. I assume there is a reason for it, but it appears to go from 2.7->2.9->3.0->3.1->3.3->3.5->3.7->3.9
 

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Thanks for sharing! I had not stumbled upon that before but it looks to be right on what I saw on most charges, 110-120 kW start followed by a drop to the 70s.

Happen to know if there's a RWD version, if there's much of a difference?
The charging curve is per battery size, not drivetrain. That is the ER charge curve, which is different from the SR charge curve.
 

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Good info. Did you track speed? On our trip down to FL, we were driving 74 or more most of the time. My roughly calculated m/kwh is 2.88. If you were driving slower, that might explain your higher numbers.

Good point about using the free charging in the per kWh states instead of the per minute states. Probably should have done that. Oops.
Great write-up. Thank you for sharing.

In addition to average speed, it would be interesting to track the outdoor temperature at your departure points and charge stops.

When I got my MME in March, I was shocked at how much the cold affected the GOM range / battery %. It's more than just a little bit, but I didn't record any detailed data to share. If you live in colder climates, better get mentally prepared for your first winter in an MME.
 

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Very nice. Great experience and data.

I have found the trip meter reset has to be "held" for a while. A short press resets time and miles, the longer press resets time, miles and the Mi/kW setting. That's the only way to get an accurate Mi/KWh is the full long reset.
 

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Great write-up. Thank you for sharing.

In addition to average speed, it would be interesting to track the outdoor temperature at your departure points and charge stops.

When I got my MME in March, I was shocked at how much the cold affected the GOM range / battery %. It's more than just a little bit, but I didn't record any detailed data to share. If you live in colder climates, better get mentally prepared for your first winter in an MME.
Having a PHEV for 3 years, the winter hit is steep - figure 40%. If you precondition while on the charger, and then drive, it shouldn't be as bad.

Our trip 2 weeks ago was high 80s most of the time, running AC constantly.

As we head back starting Sunday, I plan on tracking more variables just for fun.
 

ncaadam

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When I got my MME in March, I was shocked at how much the cold affected the GOM range / battery %. It's more than just a little bit, but I didn't record any detailed data to share. If you live in colder climates, better get mentally prepared for your first winter in an MME.
ugh - don't remind me. i haven't experienced one yet with an EV, but have heard from many friends: be prepared

if you were to estimate, range loses 15-20%? more? less?
 

Nklem

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Great write-up. Thank you for sharing.

In addition to average speed, it would be interesting to track the outdoor temperature at your departure points and charge stops.

When I got my MME in March, I was shocked at how much the cold affected the GOM range / battery %. It's more than just a little bit, but I didn't record any detailed data to share. If you live in colder climates, better get mentally prepared for your first winter in an MME.
You are spot on. On my AWD SR I have had consistent 240-258 miles at 100% per charge on the GOM and actual range. All summer temps above 55 and warmer days. My first 45-48 degree night, the other night, that went to [email protected]% or 220 at 100%. It will get worse as temps decrease. It is good to see the GOM trying to adjust for anticipated heating.
 
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