charging limitations

[JPR]

I bought an e-Golf last November (model 2019) and am basically happy with it.
I also installed a 11kW charging unit at home.
Problem: when charging, it will never charge with more than 7kW, be it at my own or any public charging station (which is supposed to deliver 22kW !).
On the parameters that I can select at the car's display, I checked "max" for the charging power.
And lately even the 7kW charging ends at a 192km range (instead of the nominal 230km).
Can anyone tell me what I'm doing wrong?
Thanks...

 

[f1geek]

The AC charger is in the car, not on the wall. The on board AC charger is rated at 7.2 kW so your car will never be able to accept more power than 7.2 kW when charging on AC power. Also, the on board charger is a single phase rectifier, so no way to accept three phase power. The on board charger will accept a maximum of 30 amps at a maximum of 240 V. That being said, the car can accept up to about 39 kW for DC Fast charging. I did read that the ID.3 should come with an 11 kW on board charger, but I know that's not much help for your car.

The range you see is what is called the Guess-O-Meter (GOM). The GOM readout is based on how fast you drive, if it is hot or cold outside, and how much heat or air con you use. GOM readout is based on your habits and will change with how you operate the car. Best of luck!

 

[manybees]

the car can accept up to about 39 kW for DC Fast charging.

Last weekend on an Electrify America DC fast charger, my 2018 e-Golf was pulling 42kW for awhile, according to the Electrify America app. That's the highest I've ever seen on a DCFC.

 

[f1geek]

Impressive! What was the state of charge, amps and volts delivered? How long did 42 kW last?

For the few occasions I haves used DCFC, I took a walk and so wasn’t watching the entire time, but never saw above 39 kW when I was actively following the session.

 

[JPR]

Thank you for your detailed answers!
If I understand right, you say that I could theoretically plug my car straight to the grid (I'm living in Switzerland where we have 240V AC singe and 400V AC tripple phase) and pull up to 40 A from the single phase, which would amount to the 7.2 kW I noticed ?
OK, but I have a 3-phase charging unit which is supposed to deliver 11kW and I suppose (I didn't measure it) it delivers it's power in form of DC-current, no?
And at a commercial charging station, marked as 22kW and featuring a type 2 plug, shouldn't that allow a DC fast charge ABOVE the 7.2kW ?
I admit I'm a bit confused...!

 

[manybees]

Impressive! What was the state of charge, amps and volts delivered? How long did 42 kW last?

For the few occasions I haves used DCFC, I took a walk and so wasn’t watching the entire time, but never saw above 39 kW when I was actively following the session.

Initial SoC was at 34% and power delivered hit 42kW at around 38% for a few minutes. It held steady at around 41kW until around 65% (I think—wasn’t paying close attention), then started slowing. Really started tailing off at just over 80% but I charged to 95% and even when tapering, it never went below 15kW. Added just over 20kWh in 36 minutes.

 

[manybees]

Thank you for your detailed answers!
If I understand right, you say that I could theoretically plug my car straight to the grid (I'm living in Switzerland where we have 240V AC singe and 400V AC tripple phase) and pull up to 40 A from the single phase, which would amount to the 7.2 kW I noticed ?
OK, but I have a 3-phase charging unit which is supposed to deliver 11kW and I suppose (I didn't measure it) it delivers it's power in form of DC-current, no?
And at a commercial charging station, marked as 22kW and featuring a type 2 plug, shouldn't that allow a DC fast charge ABOVE the 7.2kW ?
I admit I'm a bit confused...!

The e-Golf’s DC charging capability tops out theoretically at 50kW, but real world power delivery tops out at around 40kW DC power, and this will be just for a relatively short time because the charging starts to taper as the state of charge approaches 80%. DC fast chargers use the Type 2 CCS plug standard in Europe. If marked 22kW, the public DC charger won’t deliver more than that. DC fast chargers are not normally available for home use for a variety of reasons, one being that they are expensive to buy, install, and maintain and another being that residential building codes usually wouldn’t allow it because residential housing is usually not wired to deliver that much power.

The e-Golf’s AC charging capability tops out theoretically at 7.2kW (240v x 30 amps = 7.2kW), but will be less than that because of inefficiencies in the charging process. No matter what the maximum AC power a charging station is capable of delivering, the e-Golf’s AC charger can’t accept more than the theoretical max of 7.2kW. Even though your 240v 40a AC circuit can deliver more, the e-Golf can’t accept it.

Here’s a pretty good overview explanation of the difference between DC and AC charging:

https://evsafecharge.com/dc-fast-charging-explained/

Here are details about the Type 2 plugs used in Europe:

https://en.wikipedia.org/wiki/Type_2_connector

 

[f1geek]

The e-Golf on board charger only accepts single phase AC power and also the car has to be connected through either a J1772 connector or Type 2 plug (depending on what inlet came with your car) for the on board charger to communicate with the charging station. You can not directly confect the car to an electricity supply for human safety and to protect the car electronic equipment. Please do not attempt to directly connect 400 V ti the car.

As far as DC charging goes, special charging stations (typically costing around $20,000 to $50,000 for the station) convert grid AC power into DC electricity, communicate the the car computer and this charge the car battery directly, bypassing the on board AC charger. A DCFC station is known as an off board charger.

The theoretical max DCFC rate of the e-Golf is not 50 kW. From what I have read, the max amps accepted is 115 amps DC and 369 Volts DC, so 115x369= 42.4 kW is the max theoretical DC charge rate. The computer will not allow more than this amperage and voltage at any given time.

 

[manybees]

The theoretical max DCFC rate of the e-Golf is not 50 kW.

I don't know if it's correct, but the specs given at this link say that the max DC charging rate is 50kW:
https://evcompare.io/cars/volkswagen/vw_e-golf_2018/#tabs-main

 

[f1geek]

That website is wrong. Someone should shoot them a correction email.

Fastned knows their charging sh*t.

https://support.fastned.nl/hc/en-gb/articles/205205168-Charging-with-a-Volkswagen-e-Golf-or-e-up-


Best of luck!

 

[tbier]

I was just about to post that article from Fastned. I get very close to that DC charge curve the 5 or so times I've used a 50kW-150kW DC charger.

 

[miimura]

The e-Golf on board charger only accepts single phase AC power and also the car has to be connected through either a J1772 connector or Type 2 plug (depending on what inlet came with your car) for the on board charger to communicate with the charging station. You can not directly confect the car to an electricity supply for human safety and to protect the car electronic equipment. Please do not attempt to directly connect 400 V ti the car.

As far as DC charging goes, special charging stations (typically costing around $20,000 to $50,000 for the station) convert grid AC power into DC electricity, communicate the the car computer and this charge the car battery directly, bypassing the on board AC charger. A DCFC station is known as an off board charger.

The theoretical max DCFC rate of the e-Golf is not 50 kW. From what I have read, the max amps accepted is 115 amps DC and 369 Volts DC, so 115x369= 42.4 kW is the max theoretical DC charge rate. The computer will not allow more than this amperage and voltage at any given time.

The European e-Golf can charge just fine on any Type-2 charging station. The 11kW and 22kW stations are 3-phase 400V L-L and work just fine with the e-Golf. However, it is still limited by the on-board charger to 7.2kW.

 

[f1geek]

Some more info:

https://ev-database.uk/car/1087/Volkswagen-e-Golf#charge-table

It suggests the on board charger can take 2 phase power, with each phase at 16 amps for both an 11kW and 22 kW station, and 31 amps at 230 V. If you have tested this scenario and were able to pull 7.2 kW at an 11 kW station, then that suggests the EU e-Golf on board charger can indeed take two phases of AC current. VW should have the specs listed somewhere...