Everything you need to know about BMS & voltage balancing

[macd2401]

Badge Pulsing.
Although it looks like it didn't upload

 

[Stuart Wright]

Badge Pulsing.
Although it looks like it didn't upload

You can't upload videos as attachments, unfortunately. Is there a file sharing service you can use please?

 

[Stuart Wright]

Badge Pulsing.
Although it looks like it didn't upload

Don't worry, I found one, thanks

 

[rbpasapera]

What are the benefits of the BMS update ending in EU1 vs A01? Would be interesting to know if there are some benefits.

 

[Mike]

All sounds great @Stuart Wright

 

[Mg5man]

I sold my mg due to bms issues

 

[Freddy]

I need some resources. Can anyone please send me

• video of the charging light pulsing
• video of the charging light solid
• photo of the dash showing 449 volts
• photo of the dash showing 455 volts

456 volts.

 

[Cocijo]

456 volts.

Superb range!

 

[Lovemyev]

That range can’t be accurate surely ?.

 

[Cocijo]

That must be what 220miles in Eco? And if the hvac is on during the pic add another 20+! Tremendous. Great voltage too for 8000mile+ car.

 

[Electrifried]

Later today, @MilesperkWh and I are making a video to explain what BMS is and to address the concerns of ZS EV owners regarding potentially unbalanced batteries.
I will ask Miles a series of questions to answer, the purpose being to create a definitive video on the subject which addresses all the questions and concerns that people might have.
This is the list of questions:

1. What does BMS stand for?
2. What is BMS generally and why is it important?
3. Can MG ZS EV owners see the battery health?
4. What should the voltage display read?
5. What if the voltage display reads something else?
6. What is battery balancing?
7. Why have some ZS EV owners got an imbalanced battery?
8. How can a ZS EV owner identify whether their car has the particular software version?
9. What impact will an imbalanced battery have?
10. Will having an imbalanced battery damage the battery or car?
11. What should an owner who believes they have an imbalanced battery do?
12. What is the procedure for re-balancing the ZS EV battery?
13. Why does balancing a battery take so long? Is there any way to speed it up?
14. Do MG5 owners need to rebalance their battery?

Can you suggest any questions to be added to this list?
Please reply. Thanks

Why after 2 BMS updates HVCC update will my car still not do a delayed charge from Smart charger, my Dealer appears to be at a loss. The other strange aspect is after the latest update my car has started to do a balancing charge as soon as I unlock the car it disengages the lock for charger cable then immediately re locks it and starts to charge, even after having been on charge all night. It will do this approx 3 times for about 20min each time before it decides it’s done. The car seems to have a mind of its own.

 

[Tango130]

Why after 2 BMS updates HVCC update will my car still not do a delayed charge from Smart charger, my Dealer appears to be at a loss.

What smart charger do you have?

Ask your dealer to ensure that they have updated the EVCC module to allow for 10 hour delay to charge starting. The software in my EVCC that allows this is software code 1770124111.

 

[Lovemyev]

That must be what 220miles in Eco? And if the hvac is on during the pic add another 20+! Tremendous. Great voltage too for 8000mile+ car.

Running on original OEM 455 volt software here, do we think ?.

 

[Tango130]

The other strange aspect is after the latest update my car has started to do a balancing charge as soon as I unlock the car it disengages the lock for charger cable then immediately re locks it and starts to charge, even after having been on charge all night. It will do this approx 3 times for about 20min each time before it decides it’s done. The car seems to have a mind of its own.

Yes, there is only a short window to remove the charge cable before the lock actuates closed.

 

[Electrifried]

What smart charger do you have?

Ask your dealer to ensure that they have updated the EVCC module to allow for 10 hour delay to charge starting. The software in my EVCC that allows this is software code 1770124111.

My charger is a Wallbox Pulsar Plus. I got my son in law to try his e Golf on my charger in case it was a charger issue but his car charged every time we did a delayed charge on his car.
I have no idea what software is in my car as the dealer does not give any info on what they have done. It’s simply a the young lassie on reception hands your keys over has no answer to questions so you are left with no idea what has been done. I have already passed comment that there should be paperwork handed over to the Owner saying exactly what has been done to the car, as yet nothing.

 

[PeteJ]

In reply to Micky & JodyS21. My update was done on the Feb 25th and the garage is insistent that I have the latest BMS software. My third charge using the Granny Charger still give 450v and it seems a small improvement in range, however this is subjective.

 

[Electrifried]

Yes, there is only a short window to remove the charge cable before the lock actuates closed.

I appreciate that fact but this has just started happening after latest update and the relocking of the cable is immediate, it unlocks then immediately relocks within 2 seconds

 

[Freddy]

Just for info, the obdll connector I have had 4 or 5 years so don't know what chip it has.
It also looks like I'm the only one that doesn't have 100% SoH.
Not had the dodgy BMS.

 

[Cocijo]

Running on original OEM 455 volt software here, do we think ?.

And some very good careful driving too

 

[Mike]

My SOH was 98.21% last time I was able to check. This is after 15 months and 14,500 miles.