Post your MG ZS EV battery SOH data please

[Shippo]

24000 miles SOH 96.15%, was 99.31% at 12000 miles, so a drop of 3.16% over the second 12000 miles which is concerning. 4 rapid charges, the rest 7kw home charges
Fully charged 155 miles in normal mode and 455 volts.

 

[Phil Hayward]

Would the degradation be lower by only charging to 450 volts with the BMS update?

 

[Lovemyev]

24000 miles SOH 96.15%, was 99.31% at 12000 miles, so a drop of 3.16% over the second 12000 miles which is concerning. 4 rapid charges, the rest 7kw home charges
Fully charged 155 miles in normal mode and 455 volts.

I found similar figures with our Gen1 ZS EV at just over two years old and almost 20,000 miles covered.
Our predicted range after a full charge & balance ( with both trip meters reset ) was 154 miles of range ( 448 Volts ) in the normal default mode.
We where running on the Jan 15th 2021 BMS update.
Your pack voltage of 455 suggests you are running on the original factory BMS then ??.

 

[Coulomb]

Would the degradation be lower by only charging to 450 volts with the BMS update?

Yes. Voltage and temperature are the twin enablers of bad reactions that lead to degradation.

 

[Lovemyev]

I believe that the Jan15th BMS update for the Gen 1 ZS EV was intended to lower the fully charged voltage from the original factory software of 455 - 456 volts, down to 448 - 450 volts.
There had been a few instances where the main HV protection fuse on the pack had suddenly failed.
My local dealer had a fuse failure while carrying out a PDI check, prior to a delivery.
The car had to be shipped out to another dealer, because they did not have the training or equipment to carry out the job.
There was a software update produced to lower the voltage of certain vehicles at the time of their service interval.
However, this software allowed a bug into the system and caused a lot of problems regarding lose of power under load and a imbalance of the cells in the pack.
Hence the Jan15th BMS update was written.
I am pretty sure at this point, they increased the buffer at the head of the HV battery ? also.
Some “Comfort 2” updates, applied between certain dates, also had the “Buggy” software that had the same affect.
I still find it strange how the original ZS EV has cars are running two different versions of software ?.
Again, I think it was intended that ALL cars where going to be upgraded at the time of standard dealer service appointments.
But we know this has not been fully implemented, don’t we !.

 

[Shippo]

I found similar figures with our Gen1 ZS EV at just over two years old and almost 20,000 miles covered.
Our predicted range after a full charge & balance ( with both trip meters reset ) was 154 miles of range ( 448 Volts ) in the normal default mode.
We where running on the Jan 15th 2021 BMS update.
Your pack voltage of 455 suggests you are running on the original factory BMS then ??.

I honestly don't know, at my 1 year service the only update was on the infotainment system. Are there any benefits on having the bms update?

 

[Lovemyev]

I honestly don't know, at my 1 year service the only update was on the infotainment system. Are there any benefits on having the bms update?

Wow ….. That is a LONG debated subject @Shippo .
Covered over many many threads on the forum.
Most peoples stance on this subject is this, if the car is working fine, then leave well alone !.
I will edge my bet’s and say you are running on the factory software !.
There is no problem with that at all, if it’s not broke, don’t try and fix it !.
If you have a few hours to spare ( who does these days ) them just search the forum for “BMS update”.
It’s like a good book ? if you have the time to read into it.
On second thoughts ? - don’t bother mate.
It’s like war and peace .
Ask me how I know ?‍.

 

[Maciej]

How do you check SOH on new trophy?

 

[Coulomb]

How do you check SOH on new trophy?

I don't think you can at present. You have to wait for EV Watchdog or one of the others to figure it out, unfortunately. I'm sure they'll get there soon enough, so in the meantime, you can order one of the reasonable quality Bluetooth dongles. See the resources forum for recommendations.

 

[Lovemyev]

I honestly don't know, at my 1 year service the only update was on the infotainment system. Are there any benefits on having the bms update?

Wow ….. That is a LONG debated subject @Shippo .
Covered over many many threads on the forum.
Most peoples stance on this subject is this, if the car is working fine, then leave well alone !.
I will edge my bet’s and say you are running on the factory software !.
There is no problem with that at all, if it’s not broke, don’t try and fix it !.
If you have a few hours to spare ( who does these days ) them just search the forum for “BMS update”.
It’s like a good book ? if you have the time to read into it.
On second thoughts ? - don’t bother mate.
It’s like war and peace .
Ask me how I know ?‍

 

[Zoomy]

24000 miles SOH 96.15%, was 99.31% at 12000 miles, so a drop of 3.16% over the second 12000 miles which is concerning. 4 rapid charges, the rest 7kw home charges
Fully charged 155 miles in normal mode and 455 volts.

One end of my pack voltage is 100mV down on the rest, something I’ve seen with other’s too. I do wonder if there is a localised cooling issue there with the design that would lead to excess decay. The basis of this theory wasn’t from seeing Cleevely via Youtube work on a Leaf with a similar issue.

The stock BMS though was highly stressed aiui and the lower voltage now increases cycles. However as I alluded to before something was done to speed the rapid charging, which increases heat and resistance. The algorithm for SoH pre and post “BMSgate” is closed code so we will never know how SOH was and is being calculated, thus if accurate or not.

 

[BrutusSpain]

Hello from Spain
I bought a MG ZS EV (gen1) in January this year.
17000 kms covered
94.2% SOH. I'm worried about this
Do u think this is normal for this car?

I think the used app has read the usable part of battery 42.5 kwh which is 94% of 45 kwh total capacity
Is this possible?

Thank you very much, I have been reading this forum for a long time and I have learned a lot with you

sorry for my english, it's very bad

 

[Zoomy]

It could be normal Brutus, it may have had a few extra rapid charges?

 

[JohnInFrance]

(car started without brake pedal pressed/under no load) (this gives a good indication of SOH if you haven't got access to OBD2 data)

... OK, ready to be shot down here, but how do I find SoH for the battery? I understand the above, but once I've done that, where should I be looking? We don't have a OBD2 thingy or any fancy apps other than the decidedly un-fancy MG app.

 

[Runnerarne]

... OK, ready to be shot down here, but how do I find SoH for the battery? I understand the above, but once I've done that, where should I be looking? We don't have a OBD2 thingy or any fancy apps other than the decidedly un-fancy MG app.

For OBD2, look at this site: vgate icar pro: Search Result | eBay

 

[JohnInFrance]

For OBD2, look at this site: vgate icar pro: Search Result | eBay

I don't want an OBD2 device, hence why I ask the question.

 

[N2STY]

I don't want an OBD2 device, hence why I ask the question.

Don't worry it don't work on MK2 anyway?

 

[JohnInFrance]

Don't worry it don't work on MK2 anyway?

 

[BrutusSpain]

It could be normal Brutus, it may have had a few extra rapid charges?

2 rapid charges to 80%
13 rapid charges from 20% to 60%

Rest, about 150 AC charges at home to 3.45 kW

Does this car handle rapid charges well??
I know others, like Hyundai Kona or Kia Niro, with 100% charges on DC and no degradation.

 

[Delboy102000]

Firstly having looked through this correct me if I am wrong it comes to no overall conclusion. I wonder if driving style also puts degradation on the battery if driven frequently with harder acceleration.

Secondly surely all posts should have needed to show BMS numbers to be meaningful comparisons.

Thirdly Mk1 and Mk2 cars and LR. Versions need distinguishing.

Lastly stating device/app used would make data more meaningful.
In summary what can be drawn overall from the data posted.

Battery life looking good/bad
In line to get the manufacturer off the warranty hook?
As expected or not.