DCQC charging rates

[jdunmyer]

What are the typical rates of DC quick chargers? Seems like I've seen numbers as high as (at least) 55 KW. My Clipper Creek gives me 7.7 KW, so that's kind of my baseline.

I charged at a Chevy dealer today, just to see how they operate, and sat in the car, listening to the radio while charging. With the climate control 'off', the rate was showing 20 KW. It added about 60 miles of range in an hour; I had the CC 'on' for about half the time, which dropped the rate to about 17 KW. Not complaining, as the charger is free, and I was only about 7 miles from home.

Not sure why, but the dealer's Bolt was plugged in when I arrived, but it wasn't charging. I unplugged it, then replugged it when I was leaving. Perhaps they were just showing off how easy it is to charge the car..???

 

[keijidosha]

What are the typical rates of DC quick chargers?

Bosch units like what your dealer had can charge the Bolt at around 22kW peak.

EVgo units seem to be 100 or 125 amp and will charge at about 38 and 42kW peak.

ChargePoint DCFC also seem to be in the 40kW range.

New units from Electrify America, Recargo, and select EVgo DCFC sites will peak at about 55kW.

Check PlugShare.com or venders site for check-ins from other drivers.

 

[jdunmyer]

Thanks for the info!

FWIW: I didn't notice the brand of charger, but it looked about the size of your first picture, but was horizontal oriented; IE: long dimension horizontal. It has a small window with a readout that tells you what is going on during the handshake phase, etc.

Nice pics!!

 

[keijidosha]

Thanks for the info!

FWIW: I didn't notice the brand of charger, but it looked about the size of your first picture, but was horizontal oriented; IE: long dimension horizontal. It has a small window with a readout that tells you what is going on during the handshake phase, etc.

Nice pics!!

Bosch unit is sold in different configurations.

https://www.amazon.com/Bosch-25kW-DC-Fast-Charger/dp/B074Z9SG2J

 

[gpsman]

Most ChargePoint DCFC that are floor standing models (not pole mounted) are “rated” at 50 kw and tend to shove 44kw to 47kw into the Bolt.

The newest Chargepoint DCFC is “rated” at 62.5 kw (I hear it is capable of more but software limited to 62.5 kw). It will shove about 55kw into the Bolt.

The Bolt EV itself is limited to 150 AMPS of input current, so it won’t matter if you could connect to something more than 60kw. The Bolt’s maximum charge rate is 60kw as 150 amps x 400 volts.

 

[SparkE]

Most ChargePoint DCFC that are floor standing models (not pole mounted) are “rated” at 50 kw and tend to shove 44kw to 47kw into the Bolt.

The newest Chargepoint DCFC is “rated” at 62.5 kw (I hear it is capable of more but software limited to 62.5 kw). It will shove about 55kw into the Bolt.

The Bolt EV itself is limited to 150 AMPS of input current, so it won’t matter if you could connect to something more than 60kw. The Bolt’s maximum charge rate is 60kw as 150 amps x 400 volts.

Well, the Bolt's max current *IS* 150 amps, however the car steps down (pulls less current) long before getting to 400V. I *think* that it steps down (the first time) around 370V, lowering the charge current to around 105A (and thus dropping the 'charge rate' from around 55kW to around 38 kW at that point). The first step down (from 150A to 105A) happens about when the battery is 55% full.

The Spark EV, on the other hand, will pull max amps (up to 135A) until charge voltage reaches 400V (around 75% 'full'), then it slowly tapers the charge (amps pulled) to keep the battery voltage at 400V. It is more of a 'lowering charge rate *curve*. rather than a 'step down' like the Bolt does (fairly sudden drop).

Both vehicles will limit their current draw based on battery temp as well (either too cold or too hot).

 

[Telek]

Most ChargePoint DCFC that are floor standing models (not pole mounted) are “rated” at 50 kw and tend to shove 44kw to 47kw into the Bolt.

The newest Chargepoint DCFC is “rated” at 62.5 kw (I hear it is capable of more but software limited to 62.5 kw). It will shove about 55kw into the Bolt.

The Bolt EV itself is limited to 150 AMPS of input current, so it won’t matter if you could connect to something more than 60kw. The Bolt’s maximum charge rate is 60kw as 150 amps x 400 volts.

Bolt is limited to 150A below 370V, so 55.5kW. 100A after that to 380V, then 60A to 390V and 40A to 395V, then 25A and natural taper.

 

[NeilBlanchard]

I used an EVgo unit (eastbound on Mass Pike, near Exit 13) and only got around 22kW, which is pretty disappointing.

 

[GetOffYourGas]

I used an EVgo unit (eastbound on Mass Pike, near Exit 13) and only got around 22kW, which is pretty disappointing.

I'm guessing that your SoC was above 67%. That is the normal (aggressive) taper at work.

 

[NeilBlanchard]

No, it was about 35-37%. And it was a cool day, only around the mid 40's F or so.

 

[GetOffYourGas]

Interesting. Was your battery cold? That unit *should* be able to push at least 100A IIRC.

 

[JeffN]

I used an EVgo unit (eastbound on Mass Pike, near Exit 13) and only got around 22kW, which is pretty disappointing.

Very likely due to a cold battery. And remember, the battery temperature changes slowly so it might be 45F outside when you charge but the pack itself may be colder from spending the night at 30F or whatever.

In any case, if you look at the graph in my article about cold weather charging you will see that the Bolt can be limited to only around 60A at 8-10C or 45-50F which implies around 22 kW.

https://electricrevs.com/2018/10/23/frigidity-and-the-challenge-of-high-power-coupling/

 

[NeilBlanchard]

I used an EVgo unit (eastbound on Mass Pike, near Exit 13) and only got around 22kW, which is pretty disappointing.

Very likely due to a cold battery. And remember, the battery temperature changes slowly so it might be 45F outside when you charge but the pack itself may be colder from spending the night at 30F or whatever.

In any case, if you look at the graph in my article about cold weather charging you will see that the Bolt can be limited to only around 60A at 8-10C or 45-50F which implies around 22 kW.

https://electricrevs.com/2018/10/23/frigidity-and-the-challenge-of-high-power-coupling/

I had driven it about 15 miles, so that doesn't seem likely. I think the EVgo unit in question was less than 50kW.

 

[JeffN]

I used an EVgo unit (eastbound on Mass Pike, near Exit 13) and only got around 22kW, which is pretty disappointing.

Very likely due to a cold battery. And remember, the battery temperature changes slowly so it might be 45F outside when you charge but the pack itself may be colder from spending the night at 30F or whatever.

In any case, if you look at the graph in my article about cold weather charging you will see that the Bolt can be limited to only around 60A at 8-10C or 45-50F which implies around 22 kW.

https://electricrevs.com/2018/10/23/frigidity-and-the-challenge-of-high-power-coupling/

I had driven it about 15 miles, so that doesn't seem likely. I think the EVgo unit in question was less than 50kW.

Driving for only 15 minutes will have very little effect on the battery pack temperature, as noted in the article. You would have to drive at faster highway speeds like 70-75 mph (20+ kW output) for over an hour to really have much useful battery warming. It would help if the Bolt was able to share heat from the motor and and motor inverter into the battery like Tesla and the new Kia/Hyundai car’s can but the Bolt is unable to do that.

The Bolt also doesn’t have any “Winter Mode” to enable the driver to tell the battery heater to turn on before you arrive at a charging station. Tesla recently added that and the Kia/Hyundai models with a dedicated battery heater have a such a mode. There is a link to that in the article.

The only way to know your pack temperature for sure is to get an OBD II reader and the Bolt PID configuration file for your OBD reader app.

 

[NeilBlanchard]

I said about 15 miles, not 15 minutes. That included a brief stint on the Mass Pike. I have been driving EVs for about 5 years, and over 50K miles. The battery pack wasn't too cold to take 50kW. The problem is the wimpy EVgo unit.

 

[JeffN]

I said about 15 miles, not 15 minutes. That included a brief stint on the Mass Pike. I have been driving EVs for about 5 years, and over 50K miles. The battery pack wasn't too cold to take 50kW. The problem is the wimpy EVgo unit.

Oops, sorry about misreading that.

But, that implies that your 15 miles of driving was at slower city rates which wouldn’t necessarily warm the battery faster than 15 minutes of highway driving.

So, yes, I still think it is quite likely a cold battery issue. I know you’ve been around the block a few times (okay, a lot of times...) as an EV driver but the Bolt has a nearly 1,000 pound battery. It takes a lot to warm it up and what you are describing, whether 15 minutes or 15 miles, just isn’t going to make a lot of difference to a cold pack.

Ultimately, we’re both guessing. The way to know for sure is with an OBD reader.

 

[SparkE]

The best thing to do to increase charge rate on cold days is to plug it in (even at only 120V). That will tell the car to heat the battery. Plugging it in 30 or 60 minutes before leaving will tremendously increase the fast charging rate if the temps are below 40.

Driving for 15 miles isn't going to do much to warm the battery, unless you are purposefully doing fast accel (and regen) most of the time to warm the battery (by pulling OUT lots of electrons, and then putting them back in).

There are very few EVgo DCFC stations that are less than 100A (~37 kW for a Bolt) - I personally have never seen one - so the problem was either "cold battery" or "DCFC problem". If the plugshare reports don't list "gee, this unit is really slow" recently, most likely is cold battery.