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I have a 2017 Bolt. I LOVE this car for a lot of reasons.....but I digress.

I have an account with Electrify America. The last few times I’ve used one of their stations, I have not drawn anywhere near the current expected. Granted, I live in MI and a couple of times the temp was been below freezing. But I still should see 40 or 50kWhr, right? But I’ve only seen 16 or 20kWhr.

As an analytical chemist, I have to wonder what the variables are. I get plenty of current from an EVGo station (I’ve connected to several). I’ve used a couple of CP units that seem to do OK as well.

1. Is there something about about the EA system in combination with the Bolt that causes this?
2. Has anyone else seen this kind of phenomenon?
3. Am I missing something REALLY obvious?

If I’m only going to get 20kWhr then that’s no good....I can get that free from any number of Chevy dealers in the area. And they have nicely appointed customer lounges too. I’ll ditch my account and move on. I really want the EA thing to work since it’s paid for by VW getting caught with their hand in the cookie jar.

TIA for any insight into this issue. Stay healthy.

Dayle
 

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Several variables. Soc, battery temperature, max current (not power) of the charger. 20kW is not entirely impossible. That's why I only go to chargepoint because they charge by kWh instead of by minute.

-TL

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Two major things affect charge rate: State of charge (what % charge you battery is) and temperature. Our Bolts only charge at max rate below 50% state of charge. In other words, if your battery is more than 50% full, the charge rate will be reduced. There are several step downs above 50%.
If it was cold outside, most likely your battery was cold. The only way to tell for sure is to get Torque Pro and hook it up to your car. Unfortunately, there is no way to manually turn on the battery heater. I'm not sure it comes on as you're charging UNLESS you have your car "on" as you charge. In other words, after you get EA to start charging, get in your car and turn your car on as if you were going to drive away. (Obviously leave it in park).
 

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The battery heater turns on charge, even the car is off. But it has only 2kW of power, so it will taken quite a while to reach the optimum temperature window.

Theoretically the bolt can charge at 55kW max. But that rate only happens rather momentarily in practice, before tapering happens. 40kW on average is about right on a normal day.

-TL


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Discussion Starter #7
Yesterday’s charge was done when I had about 40% charge and the temp was 40F. It’ll be warmer in a couple of days (🤞) and I’ll see if temp has an effect on charging efficacy.

Dayle
 

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@Dayle Frame as others have said, this is all on the Bolt EV battery management system and not a Electrify America issue. The attached image should help you appreciate what you are seeing. This image is for Bolts prior to the 2020 model year.
29151


  • You will see max charge rate when the Battery temperature is between 77 - 112 deg F and the state of charge is below 67%
Also, Chevy made available to the dealers a "cold weather charging update" I highly recommend requesting it, search this forum for details, it is a reprogramming of the Bolt BMS for those that complain of slow cold weather charging.
 

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It is mostly the car. But under certain condition it is the charger.

Say it is a 50kW charger. 50kW is its max output at max voltage of 500V. That could means its max current capability is 100A.

When bolt's battery is nearly empty (soc close to 0%), its battery voltage could be as low as 300V. So you will see no more than 30kW charging rate even with everything ideal.

So go to a charger with higher rate if possible. Anything higher than 75kW will suffice, as bolt can only take 150A.

-TL

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@Dayle Frame as others have said, this is all on the Bolt EV battery management system and not a Electrify America issue. The attached image should help you appreciate what you are seeing. This image is for Bolts prior to the 2020 model year

Also, Chevy made available to the dealers a "cold weather charging update" I highly recommend requesting it, search this forum for details, it is a reprogramming of the Bolt BMS for those that complain of slow cold weather charging.
Was the addressed on the MY 2020? Just curious as I leave in a warm climate?
 

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If I’m only going to get 20kWhr then that’s no good....I can get that free from any number of Chevy dealers in the area. And they have nicely appointed customer lounges too. I’ll ditch my account and move on. I really want the EA thing to work since it’s paid for by VW getting caught with their hand in the cookie jar.
If you have and OBD-II reader, you can check the battery temperature.

Then, there's a nice chart of maximum charging current for a given temperature. This is for the 2017-2019 models. The 2020 appears to be a bit different.

Summary:

Although the car is capable of charging at 150A, but it will limit current based on battery temperature (and state of charge). We actually know a little about how it does that (source).
  • -30.0 ℃ / -22 ℉ — 0 amps, car will not charge at all until battery has warmed
  • -20.0 ℃ / -4 ℉ — 3 amps, very slow (1 kW, slower than home charging from a 120 volt outlet)
  • -10.0 ℃ / 14 ℉ — 12 amps, slow (4.3 kW, slower than typical level-2 home charging)
  • -0.0 ℃ / 32 ℉ — 30 amps (10.8 kW, finally faster than home charging)
  • 10.0 ℃ / 50 ℉ — 54 amps (19.4 kW)
  • 15.0 ℃ / 59 ℉ — 93 amps (33.4 kW)
  • 22.5 ℃ / 72.5 ℉ — 134 amps (48.2 kW)
  • 25.0 ℃ / 77 ℉ — 150 amps (54 kW, faster than almost all DCFC chargers can supply)
  • 40.0 ℃ / 104 ℉ — 150 amps (54 kW, faster than almost all DCFC chargers can supply)
  • 45.0 ℃ / 113 ℉ — 75 amps (27 kW)
  • 50.0 ℃ / 122 ℉ — 0 amps, car will not charge at all until battery has cooled
 

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But I still should see 40 or 50kWhr, right? But I’ve only seen 16 or 20kWhr.
...
If I’m only going to get 20kWhr then that’s no good....I
Please also use the right units. Charging rate is measured in kW, a measure of power. The charger and the car (right side of the dash when car is powered on, may need to be in enhanced layout) uses the correct units.

kWh or kWhr are a measure of energy.

If you charge at 50 kW for 1 hour, 50 kWh was dispensed. 50 kW for 2 hours --> 100 kWh
 

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I have a 2017 Bolt. I LOVE this car for a lot of reasons.....but I digress.

I have an account with Electrify America. The last few times I’ve used one of their stations, I have not drawn anywhere near the current expected. Granted, I live in MI and a couple of times the temp was been below freezing. But I still should see 40 or 50kWhr, right? But I’ve only seen 16 or 20kWhr.

As an analytical chemist, I have to wonder what the variables are. I get plenty of current from an EVGo station (I’ve connected to several). I’ve used a couple of CP units that seem to do OK as well.

1. Is there something about about the EA system in combination with the Bolt that causes this?
2. Has anyone else seen this kind of phenomenon?
3. Am I missing something REALLY obvious?

If I’m only going to get 20kWhr then that’s no good....I can get that free from any number of Chevy dealers in the area. And they have nicely appointed customer lounges too. I’ll ditch my account and move on. I really want the EA thing to work since it’s paid for by VW getting caught with their hand in the cookie jar.

TIA for any insight into this issue. Stay healthy.

Dayle
VW is “pretending” that they are electric-mobility-friendly They are still VERY MUCH INTERNAL COMBUSTION friendly. They want you comply with punishment, but want the end result to be painful to the EV crowd.
 

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VW is “pretending” that they are electric-mobility-friendly They are still VERY MUCH INTERNAL COMBUSTION friendly. They want to comply with punishment, but really want the end result to be painful to the EV crowd.
 

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If Electrify America charging stations are charging ($$) people based on time and not energy dispensed, could it be that they are deliberately ratcheting down the stations to increase the cost (and maybe only in certain locations)?
 

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If Electrify America charging stations are charging ($$) people based on time and not energy dispensed, could it be that they are deliberately ratcheting down the stations to increase the cost (and maybe only in certain locations)?
on DCFC the vehicle Battery Management System (BMS) determines the charge rate (Current) up to the station capacity. EA 150kW and 350kW stations can both deliver the max Bolt charge rate of 55kW across the entire battery pack voltage range. Anything less than that on a EA station is because the Bolt EV is limiting the charge rate due to battery pack temperature, State Of Charge (SOC), or both.

short answer, No
 

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If Electrify America charging stations are charging ($$) people based on time and not energy dispensed, could it be that they are deliberately ratcheting down the stations to increase the cost (and maybe only in certain locations)?
Some areas do not allow selling electricity by kWh unless you are a public utility. That's why EA and others charge by time. Where they are allowed to sell by energy dispensed, they do.
 

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Some areas do not allow selling electricity by kWh unless you are a public utility. That's why EA and others charge by time. Where they are allowed to sell by energy dispensed, they do.
We are in southern California. Only chargepoint is charging by kWh. Contrary to what you believe, they love to charge by minute if they can.

-TL

Sent from my SM-N960U using Tapatalk
 
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