[d287]

Mustang Mach-E Battery Charges Slowly, Overheats Quickly: Why?

Through extensive research and modeling, we dive into the Mach-E's battery issues. We also compare it to the Tesla Model Y and Volkswagen ID.4.

insideevs.com

 

[Islander]

This is a pretty damning critique of the Mach-E. Take-away line: Ford's promised software upgrade to address its battery issues "treat symptoms and do not resolve the root cause: The current Mach-E pack’s hardware-based thermal bottleneck – the plastic-carrier/passive-fin based module design – is baked in."

Hope the engineering types weigh in here. I remember Sandy Munro criticizing the ID.4 battery pack for utilizing too much metal and not enough plastic. Is this piece about the Mach-E an answer to Munro?

 

[JimmyVW]

This is a pretty damning critique of the Mach-E. Take-away line: Ford's promised software upgrade to address its battery issues "treat symptoms and do not resolve the root cause: The current Mach-E pack’s hardware-based thermal bottleneck – the plastic-carrier/passive-fin based module design – is baked in."

Hope the engineering types weigh in here. I remember Sandy Munro criticizing the ID.4 battery pack for utilizing too much metal and not enough plastic. Is this piece about the Mach-E an answer to Munro?

Let me just leave this here:

https://twitter.com/i/web/status/1409271297859805187

It’s a Mach-E charging at 11KW last summer, keeping half the street awake. Fact that it needs to make that much cooling noise for charging at 11KW max at a temp <70F is not a great sign imho.

They fixed it here later with a firmware update, but I was told that also brought the charge speed down

 

[Stinsy]

I remember Sandy Munro criticizing the ID.4 battery pack for utilizing too much metal and not enough plastic. Is this piece about the Mach-E an answer to Munro?

Sandy always criticises anything metal, well made, or that could be accessed for maintenance. He loves a crappy plastic item with flimsy clips. I get that he looks at everything from the perspective of "how could I manufacture this more cheaply" and I see how he earns a lot of money saving manufacturers money. But he isn't very good when it comes to looking at things from a customer's perspective. We want sturdy products, that can be disassembled with bolts and screws, and that have great cooling. And we don't care if a manufacturer could have saved $10 on a $50k car by making a part out of plastic rather than cast aluminium.

 

[tothemoon]

I just read this same article last night and have a reservation for a California Rt 1 AWD but am considering cancelling now...Curious what the real world charging impact is if I don't plan on DCFC'ing very frequently if at all. I've had my ID4 for nearly 3 weeks now and have over 800 miles on it and haven't DCFC'ed at all.

 

[Dana]

I agree with what Stinsy said above, but to be fair, Munro doesn't seem to advocate plastic over metal just for cost savings -- weight savings to increase efficiency is one of his main priorities as well. Lighter EVs would have more range and maybe better handling and faster braking. IMO Munro has been generally unfair in his assessment of the ID.4, but seems to me he did have some good things to say about the battery and motor/transmission assembly.

 

[d287]

You can find charging curve videos on YouTube for these cars. (Out of Spec motoring is one I remember.) I did fast charge ours once and it was moving at over 125kW.

And the two views aren’t necessarily contradictory. Sandy Munro is right that lighter materials make a vehicle more efficient and easier assembly methods make it more affordable. However, Ford just didn’t do enough engineering on this.

(As an aside, the plastic door modules he praised somewhere on one video are probably the reason that when you pull on the interior handle to close the door on a Mach E it flexes away from the door.)

 

[ChristophW]

I am just glad to have a well engineered car where it truly counts. Between this and the thermal throttling Bjorn found on the Ioniq 5 it looks like quite a few manufacturers cut corners when it comes to thermal management. I think substandard thermal management cause more battery degradation than frequent fast charging, letting the battery drain to near zero, or charging up to 100% would on its own.

 

[Islander]

I agree with what Stinsy said above, but to be fair, Munro doesn't seem to advocate plastic over metal just for cost savings -- weight savings to increase efficiency is one of his main priorities as well. Lighter EVs would have more range and maybe better handling and faster braking. IMO Munro has been generally unfair in his assessment of the ID.4, but seems to me he did have some good things to say about the battery and motor/transmission assembly.

Munro seems to think that Tesla is the gold standard when it comes to weight management. So for the fun of it, I thought I'd compare a Tesla battery to the battery in the ID.4. Please, I hope someone who's better at math and engineering will check my work and my reasoning. But ... the ID.4 battery weight is reported at 493 kg, so the ID.4 battery's ratio of total energy capacity to battery weight (kWh/kg) is 166.33. It's never easy to find straightforward Tesla statistics, but I've seen reports that the Model Y 82 kWh battery pack weight is 480 kg and its kWh/kg number is 171.26 (which would correspond to a battery pack weight of 479 kg). Now ... no argument that every bit of kg savings is worth considering, but overall, a 14 kg weight savings would cut the ID.4's curb weight by 0.66%. Again by my rough calculations, this would boost the ID.4's ideal efficiency at 70 MPH by 0.01 miles/kWh. Maybe I'm doing the math wrong or my reasoning is faulty, but it's hard for me to understand why Munro thought this was worth mentioning.

 

[d287]

Munro seems to think that Tesla is the gold standard when it comes to weight management. So for the fun of it, I thought I'd compare a Tesla battery to the battery in the ID.4. Please, I hope someone who's better at math and engineering will check my work and my reasoning. But ... the ID.4 battery weight is reported at 493 kg, so the ID.4 battery's ratio of total energy capacity to battery weight (kWh/kg) is 166.33. It's never easy to find straightforward Tesla statistics, but I've seen reports that the Model Y 82 kWh battery pack weight is 480 kg and its kWh/kg number is 171.26 (which would correspond to a battery pack weight of 479 kg). Now ... no argument that every bit of kg savings is worth considering, but overall, a 14 kg weight savings would cut the ID.4's curb weight by 0.66%. Again by my rough calculations, this would boost the ID.4's ideal efficiency at 70 MPH by 0.01 miles/kWh. Maybe I'm doing the math wrong or my reasoning is faulty, but it's hard for me to understand why Munro thought this was worth mentioning.

I think the big reason the Teslas (3/Y) are more efficient at highway speeds is the body shape is more aero with the fastback and overall lighter weight. But I picked ID.4 for the more useful cargo space and standard roof rails and trailer hitch, knowing I’d give up a bit of range on those few days a year when I do a long highway trip.

 

[voxel]

Welp... guess I might cancelling my Mach-E order at some point. I know the Mach-E only charges are 0.9C which is pretty low rate. ID.4 charges between 1.2 and 1.5C. The EV6/Ioniq charge nearly at 2C (1.9C average) which is insane. That's wickedly fast charging and at 800V too.

Charging and discharging are correlated. Explains why power on the Mach-E around 250 kW @50mph (which is 2.5C) starts getting throttled - somebody on the Macheforums has detailed charts. The battery pack is heating up and can't push out 3C/4C without increasing temperatures drastically. 1C already generates at least 4 extra degrees (Celsius) of heat.

 

[voxel]

I think the big reason the Teslas (3/Y) are more efficient at highway speeds is the body shape is more aero with the fastback and overall lighter weight. But I picked ID.4 for the more useful cargo space and standard roof rails and trailer hitch, knowing I’d give up a bit of range on those few days a year when I do a long highway trip.

To be fair, the Model Y has far more usable rear cargo space than the ID.4 (the rear area did not fold flat which bothered the crap out of me because I needed to place RC planes without them sliding around). It's just a significant price difference that most can't justify.

 

[d287]

To be fair, the Model Y has far more usable rear cargo space than the ID.4 (the rear area did not fold flat which bothered the crap out of me because I needed to place RC planes without them sliding around). It's just a significant price difference that most can't justify.

View attachment 6830

I guess it depends on what you’re carrying. I always have the rear seats up, and our full size dog crate fits in the ID.4, but hits the tailgate in the Model Y.