Plug & Charge Fail and the 80% Cliff is Real

[Dan G]

So here we have 50kw 100kw and 150kw chargers. For the small amount of time that the car reaches 150, would it make more sense to go to a 50 or 100kw charger pay less but get a more linear curve or would the curve be the same for the slower chargers? In other words if you go to a 50kw would it stay at 50kw or would you end up at like 33kw

Charging curves are usually dependent on the car, not the station. If you're at a SOC (state of charge) where the car can accept higher than 100kW, but you're at an 100kW station, then the car should charge at the max the station can output. The curve won't (or shouldn't) change based on the station. It will be a much flatter charging session, but that's because it's limited by the station capability.

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[kdryden99]

Charging curves are usually dependent on the car, not the station. If you're at a SOC (state of charge) where the car can accept higher than 100kW, but you're at an 100kW station, then the car should charge at the max the station can output. The curve won't (or shouldn't) change based on the station. It will be a much flatter charging session, but that's because it's limited by the station capability.

Right, i agree with you, which is why I hypothsize that it is possible that since the battery did not get to its max charging rate on a 100kw charger, that where the graph starts to taper (around 24mins) on the 150kw charger, that on a 100kw charging station it doesnt taper. Rather it stays at 100 because the battery should be at a lower internal temperature. That it might actuslly charge faster. Well at least until it gets 80% soc.

 

[Plutoman15]

You need to renew your plates. At that time you have to provide your odometer reading. They could charge you for the new plate sticker based on miles put on your EV since your last plate renewal. It could be variable and a lot more for plates in the future to maintain our frost heaved roads.

I think New Zealand does something with registration every year where you pay for x number of miles.

 

[silverelan]

Right, i agree with you, which is why I hypothsize that it is possible that since the battery did not get to its max charging rate on a 100kw charger, that where the graph starts to taper (around 24mins) on the 150kw charger, that on a 100kw charging station it doesnt taper. Rather it stays at 100 because the battery should be at a lower internal temperature. That it might actuslly charge faster. Well at least until it gets 80% soc.

Both Charged EVs and InsideEVs (Kyle) said that the charging profile is more driven by time than internal pack temperature. It's unique if not weird.

Since we're now seeing production cars out in the wild, I'm curious to see if the pre-prod cars from December match the newly delivered vehicles or if there's been changes.

 

[dbsb3233]

I was oversimplifying a bit. Most people probably spend only 5-10% of their miles in road trips, and even those road trips are much shorter. Your situation seems to be not so common. Perhaps when you pick your hotels for overnight stays, you have to be more selective and pick the ones with L2 chargers. How far are you traveling on these trips? How many miles do you travel per day on such trips?

Sure, most will do the vast majority of their miles near home using home charging where none of this matters. But for this purpose we were just talking about DCFC charging on road trips.

If/when we attempt to drive the Mach-E instead of the Escape, the extra hours of charging required will push it to a 2-day drive. The first day will be the long one (about 500 miles). Unfortunately hotels with L2 chargers are scarce along this route. One of the problems with hotel chargers are they're often a feature only offered by the expensive hotels, so you'd spend a lot more for that charge (often more than simply doing a full EA charge instead). But it just depends on the route. I-70 through Utah is pretty scarce. It was only a few months ago that the route even became possible, when EA added a station in Green River to fill a too-far gap.

 

[Dan G]

Unfortunately hotels with L2 chargers are scarce along this route. One of the problems with hotel chargers are they're often a feature only offered by the expensive hotels, so you'd spend a lot more for that charge (often more than simply doing a full EA charge instead).

Sounds like you've done your research for your route. But for anyone else wondering, I've stayed at plenty of hotels at the other end of the expensive spectrum that had a charger. (And would take dogs.) Plugshare has the ability to filter to show only hotels. Expedia will let you search for EV chargers, as well. Plugshare will give you the most accurate information on whether or not the chargers are working.
And don't be afraid to call the hotel and ask them to reserve the charging spot for you.

 

[DBC]

If/when we attempt to drive the Mach-E instead of the Escape, the extra hours of charging required will push it to a 2-day drive.

A long road trip with a BEV that charges at 400V with the current number of chargers is going to something of an adventure, and the longer the trip the more of an adventure. The good thing is that, if you take this route, this may result in an upgrade in your lifestyle if your idea of the relationship between hotels and chargers holds true.

But for anyone else wondering, I've stayed at plenty of hotels at the other end of the expensive spectrum that had a charger. (And would take dogs.) Plugshare has the ability to filter to show only hotels. Expedia will let you search for EV chargers, as well. Plugshare will give you the most accurate information on whether or not the chargers are working.
And don't be afraid to call the hotel and ask them to reserve the charging spot for you.

I haven't found that many at the lower end of the spectrum to have chargers but I haven't looked that closely. On Plugshare, it's my go-to site for finding chargers, but I've found it misses hotels/motels from time to time. For example, I know there are a couple of hotels/motels in Cambria which have chargers because I've stayed there, but they don't show up on the Plugshare charging map.

Great tip on calling ahead. Assuming they pay attention, might also help with keeping the charging space free of non-electric vehicles. (I've had to get staff who parked in the charging spots to move their vehicles).

 

[jhalkias]

This seems like exactly the sort of candidate for someone to tweet @ JimFarley over to bring it up. Though, I'm sure they're aware of the issues and they'll improve over time. But it doesn't hurt to raise the concern while we're still in the early adopters phase.

FYI - I sent a DM to Emma Bergg about this and she told me she has forwarded it on to that team. If I hear anything, I will let you all know.

 

[jhalkias]

This problem is already solved today by adding extra fees to EV registration fees in some states. Granted it doesn't capture the mileage driven. So someday the registration fees may be based on odometer reading to make it fair to those who drive less.

EA high rates: I actually support higher rates at EA. Just imagine if those high powered chargers were only costing 10c/KWh. They will be clogged by locals who will charge there instead of charging at home, denying those who really need a fast charge on their long road trips. The current rate seems to be a good balance to deter misuse. Those on local trips should find cheaper lower power chargers or just charge at home or destination.

This is not a big deal, as it is still comparable to gas. Also, with electric cars, you start with a full charge at home and probably get another full charge at your destination. So for a 1000 mile round trip, one may only fast charge 500 miles.

Yep. That's already happening in most states. For lack of a better method yet, they're typically adding a fixed annual "EV fee" that's supposed to replace the typical amount of gas tax paid for road funding.

But yes, since it's usually a fixed fee, heavy users benefit and light users get screwed.

Exactly, and I have rambled about this before, but these legislative actions have been prompted in several states by ALEC, and they get a great deal of funding from fossil fuel energy companies.

I would MUCH rather see a mileage rate set. Make it the same for ICE and BEV at registration. Right now we get screwed not only because of low mileage on my wife's car, but it is a PHEV, that burns some gas too where we pay the gas tax on top of the $200 additional registration fee. They charge that same $200 for a BEV and a PHEV. My wife only drove about 8,000 miles last year total. At a conservative 25mpg of gas, you would have to drive 13,000 miles in a gas car before you paid $200 in gas tax for roads.

 

[CHeil402]

I think New Zealand does something with registration every year where you pay for x number of miles.

Annual vehicle registration and inspection already track your milage in Pennsylvania for all vehicles, although they don't really do anything with that information, but they do collect it. Registration is user reported, so technically it's the honor system, but inspection is not.

 

[dbsb3233]

Exactly, and I have rambled about this before, but these legislative actions have been prompted in several states by ALEC, and they get a great deal of funding from fossil fuel energy companies.

I would MUCH rather see a mileage rate set. Make it the same for ICE and BEV at registration. Right now we get screwed not only because of low mileage on my wife's car, but it is a PHEV, that burns some gas too where we pay the gas tax on top of the $200 additional registration fee. They charge that same $200 for a BEV and a PHEV. My wife only drove about 8,000 miles last year total. At a conservative 25mpg of gas, you would have to drive 13,000 miles in a gas car before you paid $200 in gas tax for roads.

Yep, well-known issue with all fixed-rate car registrations.

The problem with tracking mileage, of course is the implementation. How to prevent cheating, how to charge all drivers (not just those that live locally), privacy issues if tracking by GPS, administative cost, etc.

 

[available_username2]

Sure, most will do the vast majority of their miles near home using home charging where none of this matters. But for this purpose we were just talking about DCFC charging on road trips.

If/when we attempt to drive the Mach-E instead of the Escape, the extra hours of charging required will push it to a 2-day drive. The first day will be the long one (about 500 miles). Unfortunately hotels with L2 chargers are scarce along this route. One of the problems with hotel chargers are they're often a feature only offered by the expensive hotels, so you'd spend a lot more for that charge (often more than simply doing a full EA charge instead). But it just depends on the route. I-70 through Utah is pretty scarce. It was only a few months ago that the route even became possible, when EA added a station in Green River to fill a too-far gap.

If driving an EV turns a drive from one day to two, you should not be making that drive in an EV. You're going to spend $50k to end up with a much worse experience? Drive the escape, or rent an ice. It just doesn't make sense yet.

 

[JamieGeek]

If driving an EV turns a drive from one day to two, you should not be making that drive in an EV. You're going to spend $50k to end up with a much worse experience? Drive the escape, or rent an ice. It just doesn't make sense yet.

Where is the fun in that?

 

[ClaudeMach-E]

A long road trip with a BEV that charges at 400V with the current number of chargers is going to something of an adventure, and the longer the trip the more of an adventure. The good thing is that, if you take this route, this may result in an upgrade in your lifestyle if your idea of the relationship between hotels and chargers holds true.

I haven't found that many at the lower end of the spectrum to have chargers but I haven't looked that closely. On Plugshare, it's my go-to site for finding chargers, but I've found it misses hotels/motels from time to time. For example, I know there are a couple of hotels/motels in Cambria which have chargers because I've stayed there, but they don't show up on the Plugshare charging map.

Great tip on calling ahead. Assuming they pay attention, might also help with keeping the charging space free of non-electric vehicles. (I've had to get staff who parked in the charging spots to move their vehicles).

For chargers at hotel/motel on Plugshare I believe users should list them when they find one that is not listed has Plugshare is a community of users, I don't think they appear automatically especially when they are private chargers.

 

[SnBGC]

Charging curves are usually dependent on the car, not the station. If you're at a SOC (state of charge) where the car can accept higher than 100kW, but you're at an 100kW station, then the car should charge at the max the station can output. The curve won't (or shouldn't) change based on the station. It will be a much flatter charging session, but that's because it's limited by the station capability.

Charging curves are dependent on both the car and the station. The car has much greater influence but the station can and does factor into it. The station has the same basic concerns as the car in some respects. There is gear at those stations for cooling and conditioning the equipment. When we commission a new DCFC station.....there is a calibration process based on the electrical service that machine has at the time. Sometimes we are able to calibrate it to provide max power.....sometimes we aren't so we set it for the max we can get with the power available from the grid at that specific location. Here in Phoenix.....we can get them in the 98%-100% most of the time. SoCal is also pretty good. Northern California we are happy with 95%-97%. My technicians tell me that no two charging sessions are the same. Too many variables. There is a wide range for charging rates. It rises and falls. It's the average we need to pay attention. The area under the curve is what matters.....not really the curve itself.

Then there is a duty cycle requirement for the vehicles. Ford wants a 5% signal. Some other manufacturers are slightly different. The station has to work within the limits that the connected vehicle stipulates. For the most part....it's all a pretty well buttoned up process with an emphasis on safety. Keep in mind that DCFCing can be very dangerous and both the station builders and EV manufacturers have multiple layers of safety and protection built into the system. If any of those systems are triggered, then the charging system derates or stops completely.

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