macchiaz-o

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115 kW charge rate is 1.92 kWh added per minute.
Don't forget energy losses. 115 kW peak power drawn from the charging station is going to be less than 1.92 kWh stored to the battery for later use. Also, some of that power will go to battery management during charging, like running coolant pumps or fans, electronics, etc.

For me, the most important number from their press release is the 10 to 80% charge in 38 minutes at best for the SR pack. That's the kind of metrics that I'd want to know when I'm thinking about how I might take a road trip with an electric vehicle -- likewise when it's too inconvenient for me, and I make alternate plans like renting a car. So far I'm not seeing much value for my own use cases with power or range analysis on marketing's 10 minute charge figures.
 

dbsb3233

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That's the kind of metrics that I'd want to know when I'm thinking about how I might take a road trip with an electric vehicle -- likewise when it's too inconvenient for me, and I make alternate plans like renting a car. So far I'm not seeing much value for my own use cases with power or range analysis on marketing's 10 minute charge figures.
I'm in the same boat -- the only L3 charging I would expect to do is for road trips. And the 10-80% number is the most pertinent to that since the road trips I would take are many hundreds of miles (typically 800 each way). Those charging times are still way too long for my tastes, so we'll just drive our ICE vehicle instead on road trips.

But there are also some buyers that won't have home charging capability and will be stuck charging at public chargers most of the time. For them, doing frequent short charges may be a way of life, so the 10-minute number could be useful to them.

Personally though, I'd never even consider getting a BEV if I didn't have secure, dependable home charging.
 

Ken7

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Just read this footnote at the bottom:

1. Estimated miles added are based on the first 10 minutes of charging

That's a bit disconcerting. That could mean just from the 10% SOC point, meaning it's not really an average of the 10-80% spread, but an average of just the first 10 minutes. Which we already knew would add miles much faster (what we usually refer to as the peak area of the charging curve).

Could this really just be a marketing spin on the existing data, and nothing really changed?
Yes, that's what I'd see on my MS too. The first few minutes would look just great, but that charge rate would rapidly, and I mean rapidly, decline.

But most importantly, if you're like most owners, 95%+ of your charging will be done at home. So much of this can be largely academic. The only reason I used to use SCs as often as I did, was that for me it was free. Better to use Elon's cash than mine. But if I'm paying, it's cheaper and more convenient to charge at home. The charging cost at most of these fast chargers really suck, so the less you use them the better...and they're not great for the battery.

One more thing, most experienced BEV drivers never hang around for that last 10-20% of charge. It goes so slowly it's just not worth the wait.
 

dbsb3233

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The only reason I used to use SCs as often as I did, was that for me it was free. Better to use Elon's cash than mine.
Although the other way to look at that is that you already paid for it within the purchase price of the car in the first place. 😉
 

dbsb3233

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Here's another nitpicky (yet meaningful) problem I have with that press release... In the headline they call it a "10-Minute Top-Off". But it actually appears to be a 10-Minute Bottom-Up.

Based on the footnote, as well as what we know about BEV charging, that 61 miles in 10 minutes likely only applies when the battery is nearly empty. That's not a "top-off". Top-offs are at the other end (adding to an already mostly-full tank to get it back to 100%).

If I pull my Mach-e into a charging station when I'm at 70%, it's probably gonna take more like 20-25 minutes to add 61 miles. (I figure 22 minutes if the charge curve is down to 50 kW at that point, which is probably in the ballpark.)
 

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After digesting this more and seeing all of the discussion, I'm actually left more perplexed and curious than before the announcement from Ford.

Guess we're just going to have to wait for real world testing from reviewers who specialize in that sort of thing.
 

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After digesting this more and seeing all of the discussion, I'm actually left more perplexed and curious than before the announcement from Ford.

Guess we're just going to have to wait for real world testing from reviewers who specialize in that sort of thing.
This is the way I'm reading it... the car charges faster than previously announced. As an engineer myself, I usually obsess over the details, but in this case I'm not. My thinking is, this is just good news and if I was to ever take it on a long trip, it will be more enjoyable than it would have been with the previously announced rates.
 

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Although the other way to look at that is that you already paid for it within the purchase price of the car in the first place. 😉
Very true, very true. ;)
 

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This is the way I'm reading it... the car charges faster than previously announced. As an engineer myself, I usually obsess over the details, but in this case I'm not. My thinking is, this is just good news and if I was to ever take it on a long trip, it will be more enjoyable than it would have been with the previously announced rates.
That's how I am looking at it also, although since I am getting a SR battery I am curious if those numbers got better also or if the initial press release was wrong regarding the ER charging and Ford is putting a positive spin on the correction.

Honestly this feels like I am living a real-live mystery novel where tantalizing clues are caged in misdirection and obfuscation. Any minute now I hope to turn the page and find out everything - but I am still only 30% through the book where the intrigue continues to build.
 

dbsb3233

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This is the way I'm reading it... the car charges faster than previously announced.
Thing is, I'm not even sure that's true. I may be wrong, but it's appearing to me like the "47 miles in 10 minutes" was always the average from 10-80%, while the "61 miles in 10 minutes" is only the average for the first 10 minutes (just being reported for the 1st time, but not actually having changed). Especially since the 10-80% 45 minute time stayed the same.

Hope I'm wrong though.
 

pbojanoski

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Thing is, I'm not even sure that's true. I may be wrong, but it's appearing to me like the "47 miles in 10 minutes" was always the average from 10-80%, while the "61 miles in 10 minutes" is only the average for the first 10 minutes (just being reported for the 1st time, but not actually having changed). Especially since the 10-80% 45 minute time stayed the same.

Hope I'm wrong though.
For the engineers and enthusiasts, this drip drip of information is beguiling. For the average Joe out there it is probably just fine, but to those on this board it almost does more harm than good. Reading above all the calculations, presuming, guessing, hoping, is both exciting and maddening. I really do think Ford has more "real" information it could release, but chooses not to. Maybe they want to keep the excitement for when the car is closer to being available for purchase. Can't say they'd be wrong in that assessment, but it certainly seems to playing with the heads and emotions of many on this board! 🤔:oops:😵🥴
 

ChasingCoral

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I'm in the same boat -- the only L3 charging I would expect to do is for road trips. And the 10-80% number is the most pertinent to that since the road trips I would take are many hundreds of miles (typically 800 each way). Those charging times are still way too long for my tastes, so we'll just drive our ICE vehicle instead on road trips.
For me, I mainly want to know how long it takes to give me about 2 hours of driving before the next stop. However, I've taken road trips and needed a bit extra to get home. In those cases a 10 minute 60 mile option sounds great!

Honestly this feels like I am living a real-live mystery novel where tantalizing clues are caged in misdirection and obfuscation. Any minute now I hope to turn the page and find out everything - but I am still only 30% through the book where the intrigue continues to build.
More like they tore out the last half of the pages and are tossing them to us, one at a time, in random order.
 

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OK, so I've been reparsing the press release and there is no way to logically resolve the self contradictions that makes sense unless Ford really blew it. Since they are using similar batteries as many other BEVs, that just doesn't seem likely.

Assuming a simple 10% buffer in the ER and with RWD and taking the press release literally (session starts at 10% SOC), the following can be derived:
  • Mi/kWh for all calculations is 3.33 = 300mi / 90kWh
  • 10%-80% charge is 63 kWh = 70% * 90
  • first 10 minutes of charging draws 18.6kWh = 62 mi / 3.33 mi per kWh
  • first 10 minutes average draw is 116.25 kw = 18.6kWh / 0.16 hr
  • After 1st 10 minutes battery has 27.6 kWh = 9kWh + 18.6 kWh
  • SOC after 10 minutes is 30.67% = 27.6kWh / 90kWh
  • Draw still needed to get to 80% is 44.4 kWh = 63kWh - 18.6kWh
  • Average draw for remaining 35 minutes is 76.11kw = 44kwh / (35min/60min/hr)
That means the AVERAGE draw going from 10%-31% is 116kW, which is a paltry 77% of the theoretical max of 150kW. If instead we assume that the footnote is wrong and they didn't update the total charge time, then the 62mi per 10 minute average is MUCH more in line with other BEVs:
  • Average miles added in a 10 minute stretch = 62
  • Average draw is 116kw = 18.6kWh / 0.16 hr
  • Average percentage drop in draw over 10%-80% charge session is 77% = 116/150
  • Time to charge from 10%-80% is 32.5 min = 60 min/hr * 63kwh/ 116kw
 
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Billyk24

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OK, so I've been reparsing the press release and there is no way to logically resolve the self contradictions that makes sense unless Ford really blew it. Since they are using similar batteries as many other BEVs, that just doesn't seem likely.

Assuming a simple 10% buffer in the ER and with RWD and taking the press release literally (session starts at 10% SOC), the following can be derived:
  • Mi/kWh for all calculations is 3.33 = 300mi / 90kWh
  • 10%-80% charge is 63 kWh = 70% * 90
  • first 10 minutes of charging draws 18.6kWh = 62 mi / 3.33 mi per kWh
  • first 10 minutes average draw is 116.25 kw = 18.6kWh / 0.16 hr
  • After 1st 10 minutes battery has 27.6 kWh = 9kWh + 18.6 kWh
  • SOC after 10 minutes is 30.67% = 27.6kWh / 90kWh
  • Draw still needed to get to 80% is 44.4 kWh = 63kWh - 18.6kWh
  • Average draw for remaining 35 minutes is 76.11kw = 44kwh / (35min/60min/hr)
That means the AVERAGE draw going from 10%-31% is 116kW, which is a paltry 77% of the theoretical max of 150kW. If instead we assume that the footnote is wrong and they didn't update the total charge time, then the 62mi per 10 minute average is MUCH more in line with other BEVs:
  • Average miles added in a 10 minute stretch = 62
  • Average draw is 116kw = 18.6kWh / 0.16 hr
  • Average percentage drop in draw over 10%-80% charge session is 77% = 116/150
  • Time to charge from 10%-80% is 32.5 min = 60 min/hr * 63kwh/ 116kw
If the average draw is only 117kW fo rthe first 31% SOC and then only 76kW for 31 to 80% SOC, would the charging curve change (faster?) if a setting in the vehicle would limit the max kW rate of charging to 120kW? Might be cheaper on the EA system?
 

timbop

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If the average draw is only 117kW fo rthe first 31% SOC and then only 76kW for 31 to 80% SOC, would the charging curve change (faster?) if a setting in the vehicle would limit the max kW rate of charging to 120kW? Might be cheaper on the EA system?
For sure, but i doubt ford would allow it. The key is that i dont think those numbers are right
 
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