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Can any of the owners who have received their cars already comment on the DCFC curve? Since the Blazer and Equinox are going to be based on the Lyriq, having this info would be very helpful for a lot of people. Specifically, if you've done a DCFC session, can you comment on

  1. Ambient temperatures
  2. How many KW the charger was rated for, and if it was broken (eg liquid cooling pump not working on an EA, so only able to get 32KW)
  3. How much power the car was able to draw at various states of charge (SOC)
  4. How much power the car was able to draw past 80%, if you got there
Thanks
 

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Quick charge to 80% to test the process/app for FPL Evolution charging station. The FPL app creates a charging curve. The temperature was about 82 Degrees.
Thanks for posting. Wow, that doesn't look very good at all. 65% - 70% at about 75kW, and 70-80% at less than 60kW. And 18 minutes for only 15% added charge (80 miles).

Any idea regarding the charger kW output rating? 150kW, 350kW? Were you the only one at the site, or several people potentially sharing / limiting the output?

It should be better at lower state of charge. Lyriq is supposed to be over 190kW, but I don't think anyone has seen anywhere close to that. If you have the opportunity to fast charge at a lower state of charge (starting at 10% or 20%), it would be welcome info.
 

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Thanks for posting. Wow, that doesn't look very good at all. 65% - 70% at about 75kW, and 70-80% at less than 60kW. And 18 minutes for only 15% added charge (80 miles).

Any idea regarding the charger kW output rating? 150kW, 350kW? Were you the only one at the site, or several people potentially sharing / limiting the output?

It should be better at lower state of charge. Lyriq is supposed to be over 190kW, but I don't think anyone has seen anywhere close to that. If you have the opportunity to fast charge at a lower state of charge (starting at 10% or 20%), it would be welcome info.
I forgot to post the Charger Max speed: 120kW. No one else was using any of the other 3 chargers at the time.
 

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For the Lyirq and other Ultium Vehicles you need Chargers that can put out a lot of Amps, to push up the speed.
Yes, but that doesn't account for the ramp down 65-80% shown here. Any limitation with current delivery (amps) would be seen at the beginning of the cycle, when the battery voltage is low and the amps are high. As the car charges the voltage increases - less amps are needed. So if charger limited by amps, the power would actually go up over time. That's not what was recorded in this session.

What we would really want to see is the data from charging starting at a much lower state of charge, as that is where the most power should be able to be pulled.
 

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Now that more and more cars are out there, I’m hopeful lots of data will become available. Those of you with a car, please help.
I'm really hoping Tom Moloughney get his hands on one soon for a 70 MPH range test and a full charging curve. There seems to be exactly zero press cars for use in non-controlled circumstances, so maybe a customer can lend him the car for a day or two.
 

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Yes, but that doesn't account for the ramp down 65-80% shown here. Any limitation with current delivery (amps) would be seen at the beginning of the cycle, when the battery voltage is low and the amps are high. As the car charges the voltage increases - less amps are needed. So if charger limited by amps, the power would actually go up over time. That's not what was recorded in this session.

What we would really want to see is the data from charging starting at a much lower state of charge, as that is where the most power should be able to be pulled.
I believe the nominal voltage for the Lyriq is at most 380 Volts, and you would need a Charger than can supply at least 500 Amps to get it's max 190 kW charge rate.

Anyway... here is an example charge curve from a GM patent, shows what is assumed to be the Lyriq charge curve based on time and SOC.

Falls off a cliff around 80% SOC GM is very protective of their battery.
Rectangle Slope Font Parallel Plot
 

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So here’s a quick question about charging… do the chargers supply a fixed voltage and control current to limit charge rate? Or do the chargers vary the voltage to control charge rate? I assume that the car sends a message to the charger telling it how much power to supply, and the charger responds by either current limiting or voltage reduction.
 

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So here’s a quick question about charging… do the chargers supply a fixed voltage and control current to limit charge rate? Or do the chargers vary the voltage to control charge rate? I assume that the car sends a message to the charger telling it how much power to supply, and the charger responds by either current listing or voltage reduction.
This is all dictated by the the comms from the car - it controls the process and the charger is a slave. To cause significant current flow, the charger voltage does need to be higher than the battery voltage (and due to cable losses). This voltage is set by the car, as well as a current limit. As the state of charge changes, the car adjusts this process. Toward the end the voltage is fixed, and the current ramps down as the battery reaches near fully charge.

But all this can also be limited by the capability of the charger, in both max kW and available amps. Clearly a 120kW charger can't get the Lyriq its 190kW power request.
 

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Anyway... here is an example charge curve from a GM patent, shows what is assumed to be the Lyriq charge curve based on time and SOC.

Falls off a cliff around 80% SOC GM is very protective of their battery.
Thanks for sharing this chart again. It does show that if starting above say 65% SOC, it would probably already be in the ramp down area - and not spend much time at max 190kW draw regardless of charger capability (120kW charger in this case - but nowhere near that level was seen). But would have still expected more power in that ramp.

What the post described is more of the end of charge ramp shape if started at zero SOC (from the patent graph). The idea of the patent is you can still have a high power draw for some time even if you start at a higher SOC, and sustain a higher ramp level also. That was not seen in the data gathered, so something is still amiss. But we really need to see a charge start at lower SOC, and with a more capable charger.
 

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Also have to look out for situations like this:
Where the Charger is limited by the cable and will not deliver anywhere near what the Charger is supposedly capable of.
(180 kW Charger limited by a 200 AMP cable and will only give 80 kW to the Rivian.)
 

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A little extrapolation and math from published figures on DCFC found on Cadillacs official site: EV Charging & Finding Charging Stations | LYRIQ Quick Start Guide

“ 76 miles of range in 10 minutes of charging or 159 miles of range in 30 minutes of charging”

76 miles is equivalent to 24kwh on the lyriq (76/312miles X 100kwh battery). Achieving 24kwh presumably at the most favorable part of the charging curve is only equivalent to 144kwh average over those 10min. A far cry from the 194kwh peak charge rate. Can’t sustain 194kwh for 10min Vs attains 194 for a few minutes the drops off massively to come to an average of 144kwh over the 10min? The latter is probably worse.

159 miles in 30min? roughly 50kwh, which means average rate of charge is 100kwh over the most favorable part of the charging curve (probably in the 5-60% SOC range).

Interestingly, previous publications from at least may 2022 or older state 30min charge should add 195miles. Not sure if the 159miles on Cadillacs website is a typo, but it seems cadillac has realized that their car doesn’t charge as quickly as anticipated. Could this be remedied by a future OTA update? Cadillac Lyriq first look: At $60,000, my biggest question is will GM make enough of these?
 

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Data from my 1462 mile trip
Total DC Charging time = 4 hour and 8 minutes
Total Cost = $79.72 using the Electric America Charging network
Fastest charging speed seen = 173 kW
Pre-condidtioning comes on automatically when a Charger is mapped to
Total Energy used = 481.4 kWh
481.4 kWh is equal to 14.3 gallons of gasoline. That would equal to getting 102 miles per gallon
1462 miles / 481.4 kWh = 3.037 miles per kWh. 3.037 miles per kWh x102 kWh ( battery size ) = 309.7 miles for trip average miles for complete battery range ( EPA range = 312 miles )
 

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Data from my 1462 mile trip
Total DC Charging time = 4 hour and 8 minutes
Total Cost = $79.72 using the Electric America Charging network
Fastest charging speed seen = 173 kW
Pre-condidtioning comes on automatically when a Charger is mapped to
Total Energy used = 481.4 kWh
481.4 kWh is equal to 14.3 gallons of gasoline. That would equal to getting 102 miles per gallon
1462 miles / 481.4 kWh = 3.037 miles per kWh. 3.037 miles per kWh x102 kWh ( battery size ) = 309.7 miles for trip average miles for complete battery range ( EPA range = 312 miles )
Interesting note here is the 2024 EPA range seems to have been changed to 308 Miles.

Edit: Oh one question... what was the average temp during this trip?
 

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Data from my 1462 mile trip
Total DC Charging time = 4 hour and 8 minutes
Total Cost = $79.72 using the Electric America Charging network
Fastest charging speed seen = 173 kW
Pre-condidtioning comes on automatically when a Charger is mapped to
Total Energy used = 481.4 kWh
481.4 kWh is equal to 14.3 gallons of gasoline. That would equal to getting 102 miles per gallon
1462 miles / 481.4 kWh = 3.037 miles per kWh. 3.037 miles per kWh x102 kWh ( battery size ) = 309.7 miles for trip average miles for complete battery range ( EPA range = 312 miles )
3.037 miles/kWh .... not bad.

For context and referrence:
 
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