MG ZS EV battery Balancing - battery knackered?

At the end of every full charge my ZS takes at least a 4 hour balancing charge at 0.3kW. Sometimes 6 hours.

This is in addition to the very poor fast charging and very low battery capacity compared to specification.

Max charge rate ever has been 36kW. Spec 76kW.
Max charge from zero to full 32kWh. Spec 44.5kWh.

MG will not accept that there is a problem because diagnostic says battery is in good health. PS last time we used DC charging was 2 months ago and before that 6 months and car is used daily.

Does anyone else have the balancing problem?

Have you used an OBD to check the SOH of the car?

That does sound odd

How is your range? does it tie in with 32kWh or 44kWh?
If you reset the trip meter, from a full charge, what range do you achieve on a long run and what was the Miles/kWh for the same journey?

MG did - 95% at 40k miles.

Striker said:

That does sound odd

How is your range? does it tie in with 32KWh or 44KWh?
If you reset the trip meter, from a full charge, what range do you achieve on a long run and what was the Miles/KWh for the same journey

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Ties with 32kWh. Energy in and out balance give or take some losses.

andymgzs said:

Ties with 32kwh. Energy in and out balance give or take some losses.

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Did you run the battery down so the GOM said zero miles range remaining then charged with 32kWh? I'd say the range & miles per kW is more important than the amount of energy put into the battery in determining it's health too.

I often only get 30-40kW charge speed (max 94kW) but it depends on so many factors and if you don't use it much what's the problem?

Equalisation Charging / Balancing takes on average 8.5 or 11.5 hours depending on battery type so your time sounds fine?

andymgzs said:

Ties with 32kwh. Energy in and out balance give or take some losses.

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To me, that is the best evidence that you have to demonstrate that their is an issue with the battery
What sort of miles/kWh do you get on average?

The dealerships must get quite a few complaints about not achieving the advertised range, but this isn't the same, if you could document...
Charged capacity, miles achieved, Mile/kWh over a number of journeys, then present a file of information
I could still understand them being sceptical of the figure you supply on the amount of energy supplied, I assume that you're getting that off either your home charger or meter, they have no way of knowing that this is accurate
Your challenge will be presenting sufficient, clear data that separates you from someone who doesn't understand variable range on an EV

andymgzs said:

MG did - 95% at 40k miles.

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Andy - This is a ZS EV Gen1 of course ?.
Tell me, what software is the car running on ?.
The original factory software or has the BMS update been carried out ?.
Your four hour balance cycle may suggest the latter is the case.
Speaking from experience, balance cycle on original software is usually 30 minutes to about 1 hour.
Post BMS update, I could never get it below 2.5 - 3,0 hours !.

No idea. It goes into service every year and the dealer kick the tyres and charges me ~£100. Other symptoms suggest to me it knackered.

Striker said:

To me, that is the best evidence that you have to demonstrate that their is an issue with the battery
What sort of miles/kWh do you get on average?

The dealerships must get quite a few complaints about not achieving the advertised range, but this isn't the same, if you could document...
Charged capacity, miles achieved, Mile/kWh over a number of journeys, then present a file of information
I could still understand them being sceptical of the figure you supply on the amount of energy supplied, I assume that you're getting that off either your home charger or meter, they have no way of knowing that this is accurate
Your challenge will be presenting sufficient, clear data that separates you from someone who doesn't understand variable range on an EV

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I hope my meter is accurate. Ps I use a Zappi and I have verified it with Zappi, independent CTs and meter readings.

I has become irrelevant because it goes back in 11 months and we never use it on a road trip because of poor charging speed and battery capacity.

You should have the battery soh on your service report.

The OP dosen't provide much specific information: here I'm assuming a gen 1 ZS EV and charging at home on 7kW AC charger? (not granny, surely?)

No, had no problems on a gen 1 I owned for a few years; Always followed the 80% charge rule for NMC battery chemistry, then charged to 100% with balance every six weeks or so; always took exactly 105mins to balance in every case. 32A 7kW Wallbox pulsar plus, overnight off-peak.

Worth checking with your service centre that you have the latest SW updates (some earlier versions did have a bug with charging and balancing). On a home 7kW charger, in which case there may be a possibility that the charger be checked out by sparkie for that trickle charge phase in particular. If a granny charger, well, of course may take a very long time.

bzr160 said:

You should have the battery soh on your service report.

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95%. My learned colleagues on this site have told me that MG have hardwired the SOH and it bears no relation to the actual health.

Computer says it’s ok so it must be despite PPP.!

Also, charging speed not covered by warranty so they can dial it back as much as they like with a software reset. Mine - ~ 50% charge power at best.

andymgzs said:

95%. My learned colleagues on this site have told me that MG have hardwired the SOH and it bears no relation to the actual health.

Computer says it’s ok so it must be despite PPP.!

Also, charging speed not covered by warranty so they can dial it back as much as they like with a software reset. Mine - ~ 50% charge power at best.

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Forget VW emissions scandal, it’ll be MG with SOH!

Maybe you never had the full amount of parts in your battery. I never got a sunroof due to shortages…