Charging efficiency.

[peter]

Having suffered from the bad BMS software I've been gathering data on how many kWh my battery has been able to charge empty to full.
I'm glad to say it has recovered.most of its capacity and is now taking in around 40kwh according to my OHME charger this compares to around just 30kwh at the peak of my problem.
Does anyone however know if this figure would be a gross or net value?
I know chargers are not 100% efficient. I.e. if charger was 90% efficient and I consumed 40kwh of electricity then my battery would actually only be taking 36kwh.
Interested to hear if anyone knows efficiency of the mg charge and whether the smart chargers give you a gross or net value?

 

[JodyS21]

MG ZS EV

All details and specs of the MG ZS EV (2019-2021). Compare price, lease, real-world range and consumption of every electric vehicle.

ev-database.uk

WLTP Ratings​

Range	163 mi
Rated Consumption	295 Wh/mi
Vehicle Consumption	260 Wh/mi

Rated = official figures as published by manufacturer. Rated consumption and fuel equivalency figures include charging losses.
Vehicle = calculated battery energy consumption used by the vehicle for propulsion and on-board systems

So that means MG state (163x295) 48.085kWh is how much mains AC juice it will take in total to charge the car up from empty using the onboard charger.

I believe the Vehicle Consumption figure is a guess/calculation by ev-database, as it works out that 260Wh/mile is the highest figure which multiplied by 163, is less than 42.5Kwh which is generally believed to be the amount of usable battery available to us.

 

[peter]

That's helpful to know. That means I still have a way to go yet then before my battery is fully back to health. So target from charger is 48 and I'm on about 40 at the moment.

 

[JodyS21]

That's helpful to know. That means I still have a way to go yet then before my battery is fully back to health. So target from charger is 48 and I'm on about 40 at the moment.

I think that is correct based on their official figures.
That would of course be from a totally depleted battery, so unless you left the heating on in ready mode etc to TOTALLY drain the battery to it's lowest allowable state.

 

[peter]

I think that is correct based on their official figures.
That would of course be from a totally depleted battery, so unless you left the heating on in ready mode etc to TOTALLY drain the battery to it's lowest allowable state.

Yes. I've been factoring in state of charge into my calculations and grossing up. I.e. If I take in 20kwh from 50% SOC then it's 40kw for 100.