Is GeniePoint 11Kw charging being overstated?

[Clanduncan]

I have noticed this on a few occaisions whilst using a GeniePoint charger. I know my car (BMW i3 94Ahr) can charge at up to 11kW connected to a 3-phase 22Kw charger. Indeed the charger in question seems to deliver exactly that, at around 10.5-11Kw. However, and here lies my conundrum, my car only reports receiving (or charging by) around 2/3 of that. Most recent example is 22Kw delivered by GeniePoint on a 2hr connection, but only charged up by 15Kwhrs, which seems closer to the standard 7kw I get at home! This is independant of which charger I use on that particular site. Which is an ASDA site by the way, and still free for Type 2 charging.

I'm not particularly bothered about this apparent disparity, but I'm curious about it because if I started using the 50kw charger (which is chargeable) am I going to see the same overstated charge? It would be particularly interesting if I did a full (10-100%) charge at 50k and GeniePoint charged me for 37Kwhrs received, especially when my battery is only a 33Kwhr item!

I know that there are some losses in charge transmission, but this seemes excessive. Any thoughts?

 

[eNate]

I've calculated about 10% loss in the i3 Level 2 charging, nowhere near what you're suffering. That energy has to go somewhere — it can't just disappear. I have trouble believing the car could convert that much to heat and let it drift away, with no ramifications.

DCFC is another animal all together. Unlike L2, which suffers efficiency loses in the car when converting AC to DC in the built-in inverter, DCFC is going directly to the battery. The losses there are heat generated on the cells and operation of the cooling system.

 

[3pete]

Most recent example is 22Kw delivered by GeniePoint on a 2hr connection, but only charged up by 15Kwhrs

How are you arriving at the 15kWh value that went into the car? The i3 doesn't make this easy to discern. Are you calculating it from the % readout on the dash, or going into the service menu for batt. ladung?

And what % were you at when you plugged in and when you left? The i3 ramps down the charge it can accept as the battery gets full. I'm not sure where exactly that happens on an 11kW connection but it is likely between 80-90%. So after you hit that threshold, you're no longer maxing out the i3s 11kW chargers due to battery chemistry limitations. The last few percentage points are charged close to 1kW on my 60ah.

 

[Arm]

I have noticed this on a few occaisions whilst using a GeniePoint charger. I know my car (BMW i3 94Ahr) can charge at up to 11kW connected to a 3-phase 22Kw charger. Indeed the charger in question seems to deliver exactly that, at around 10.5-11Kw. However, and here lies my conundrum, my car only reports receiving (or charging by) around 2/3 of that. Most recent example is 22Kw delivered by GeniePoint on a 2hr connection, but only charged up by 15Kwhrs, which seems closer to the standard 7kw I get at home! This is independant of which charger I use on that particular site. Which is an ASDA site by the way, and still free for Type 2 charging.

I'm not particularly bothered about this apparent disparity, but I'm curious about it because if I started using the 50kw charger (which is chargeable) am I going to see the same overstated charge? It would be particularly interesting if I did a full (10-100%) charge at 50k and GeniePoint charged me for 37Kwhrs received, especially when my battery is only a 33Kwhr item!

I know that there are some losses in charge transmission, but this seemes excessive. Any thoughts?

I thought the maximum charging rate for an i3, regardless of year, for AC was 7.2kWh.

 

[eNate]

European 3-phase voltage (380) with a fixed 30A or 32A EVSE jumps from 7.7 kW (240 volts in the US) to 11kW.

 

[Arm]

European 3-phase voltage (380) with a fixed 30A or 32A EVSE jumps from 7.7 kW (240 volts in the US) to 11kW.

Got it thanks

 

[Clanduncan]

How are you arriving at the 15kWh value that went into the car? The i3 doesn't make this easy to discern. Are you calculating it from the % readout on the dash, or going into the service menu for batt. ladung?

And what % were you at when you plugged in and when you left? The i3 ramps down the charge it can accept as the battery gets full. I'm not sure where exactly that happens on an 11kW connection but it is likely between 80-90%. So after you hit that threshold, you're no longer maxing out the i3s 11kW chargers due to battery chemistry limitations. The last few percentage points are charged close to 1kW on my 60ah.

I use a bluetooth ODB2 dongle to monitor AC charging power, along with the 'Electrify App'. This shows the amount of battery actually charged, charging rate, along with lots of cell voltage, SOC, SOH info etc. In that instance above, % at start of charge was less than 25%. Then the 15Kwhrs received would only add about 50-60%, totalling a max of 80% on the day in question.
Eventually I solved this issue by buying a 3-phase 22Kw capable charging cable, i.e. 3x 32A. My dongle then reported a full 10.5kwhr charging rate, as per the cars limit of 11kw (or 3x 16A) from the Geniepoint chargers.

Still, this does show that the Geniepoint charger could have overcharged users (monetarily), if they aren't careful, by claiming a different charge sent than received.