Battery equalisation charge

[NAnd]

Hi ppl I have just tried to do my first battery equalisation charge MG ZS EV. I missed when the car got to 100% charge. How do I know if the the equalisation manouvre (whatever it is called) actually happened? Nothing apparent from either the car itself or the MG app. So I am in the dark whether this worked or I just wasted the last few days.

 

[Coulomb]

How do I know if the the equalisation manouvre (whatever it is called) actually happened?

I have the Mark 1 (non facelift) model. On that, the MG logo LEDs go solid when balancing (as opposed to "breathing" when charging). I think that the dash will show 100% and not charging, but to see that without disturbing the balance charge you have to be at the driver's window looking in, and use the key fob lock button to turn on the display. Do NOT unlock as that will temporarily stop the charge, and it may not resume the balance after the 30 seconds.

You could also check the charge current reported by the EVSE, especially if it has a convenient WiFi connection and app. Unfortunately, if you charge at low power as I do, you may not notice the early balancing, which sometimes "limits" to some 4kW. I usually charge at 3.5kW max, to use up excess solar. But you will see the late part of balancing, where the car draws less than 400W, and way less than that goes into the battery.

On my MG4, I can use the app, which shows the power going into the HV battery. If you have a facelift ZS, you can presumably do that too. Unfortunately, it doesn't say that it is balancing. But it shows the estimated end of charge time as the same as the present time. This apparently happens only when balancing. My MG4 can balance at 80% etc. I don't know if the facelift ZS can do that.

After the charge is finished, I'm not aware of any way to tell that the balance has happened. I find that my ZS will often do a second balance charge, but I have to wait at least 10 minutes from the last attempt.

 

[NAnd]

thanks for your reply.

sounds like I mucked things up and wasted the last 2 days. After the car was at 100% I unlocked the car and sat in the drivers seat to see if i could find anything to say that balancing was happening. After unplugging I turned the car on and the screen said syncronisation was required. So I plugged the car back in and left it on trickle until the green charging lights (where you plug into the front of the car) went totally out. When I unplugged and turned on again there wa no message about synchronisation.

Car owners manual is totally useless. I had to search the pdf to even find equalisation and then it didn't say what you actually need to do. I only found out about equalisation last week when the car was in for a service. So this is all new to me. Only found this group yesterday.

 

[Coulomb]

Only found this group yesterday.

Welcome to the forum!

You'll probably find lots of answers here.

The message about synchronisation is not familiar to me. It sounds like a phone and/or Bluetooth issue to me, not related to balancing.

 

[Gadget Geek]

When charging, the green lights slowly pulsate. If the green lights have gone off, then I would be confident that the equalisation charge was completed.

 

[GaryMG4]

With the Zappi the car tells it 'charging complete', the granny via the Tapo shows <1 w consumption.

 

[maskull]

I'm pretty confused about this subject . On my PFL MG 5 I could see in my bonnet app slow down as it reached 100%.
On my facelift ZS Trophy the car showed at 100%,yet the Bonnet app showed the car still charging at 6kW approximately.
Is this the balance charge period ? I was scared to leave it charge any further for fear of damaging the battery.

 

[MG Clive]

On my facelift ZS Trophy the car showed at 100%,yet the Bonnet app showed the car still charging at 6Kw approximately.
Is this the balance charge period ? I was scared to leave it charge any further for fear of damaging the battery.

This is how it should be, once it's reached 100% charge, it will still show the full 6kW for a few minutes, but this will gradually decrease over the next 10 minutes or so until it shows 0kW, this is the balance charging time.

 

[maskull]

This is how it should be, once it's reached 100% charge, it will still show the full 6kw for a few minutes, but this will gradually decrease over the next 10 minutes or so until it shows 0kw, this is the balance charging time.

That sets my mind at rest thanks . Just to be clear you mean 0Kw on the app ?

 

[MG Clive]

That sets my mind at rest thanks . Just to be clear you mean 0Kw on the app ?

Yes it'll show 0kw 'Charging Power' on the app when it's completely finished charging and balancing.

 

[maskull]

Yes it'll show 0kw 'Charging Power' on the app when it's completely finished charging and balancing.

I'll leave it run next time then

 

[MG Clive]

Ill leave run next time then

Also bear in mind, it may take longer than 10 minutes if the battery is older, or if it has never been balanced before. I said 10 minutes or so in my previous post because that's all it takes for mine, but mine is only a year old with 2k miles.

 

[maskull]

Also bear in mind, it may take longer than 10 minutes if the battery is older, or if it has never been balanced before. I said 10 minutes or so in my previous post because that's all it takes for mine, but mine is only a year old with 2k miles.

Mine is 2 years old; no idea if the last owner looked after it. I'll probably plug it in overnight

 

[Joules]

Hi ppl I have just tried to do my first battery equalisation charge MG ZS EV. I missed when the car got to 100% charge. How do I know if the the equalisation manouvre (whatever it is called) actually happened? Nothing apparent from either the car itself or the MG app. So I am in the dark whether this worked or I just wasted the last few days.

Hi NAnd, when I'm charging to 100% I check the electricity usage on my Octopus Go app the following day. You can see it tail off as it balances. Hope this helps.

 

[wazmac]

When you are charging up to 100% charging the power consumption rate will be 2kW/7kW/11kW (depending on your charger supply). When the BMS is 'balancing' (after the battery has reached 100%) the battery will only be drawing 0.3kW. This might be for 30 mins or it might be for 2 hrs, depending on how much equalisation is required. As far as I know, you need to be watching the charging device app to see this happen. Once the balancing is complete the power draw will be zero. It would be great if there was an option in the MG app or on the dash display to see a live estimate of the cell equalisation, or maybe an alert when it was required.

And of course this equalisation only happens when you are charging from an AC supply, not a DC fast charger.

More info is available at EV Battery Cell Balancing - EV World

 

[EVentropy]

This is how it should be, once it's reached 100% charge, it will still show the full 6kW for a few minutes, but this will gradually decrease over the next 10 minutes or so until it shows 0kW, this is the balance charging time.

This is not what happens with my MG4 SE SR 25k km. 2023 demo
My observations:
100% is triggered by cell voltage of highest cell hitting 3.65V
HighestV/Lowest V cell Delta at this point is 265mV.
On hitting 100%, power in drops to ~300W instantly per wasmac above
"Balancing" takes up to half an hour and stops at delta of ~150mV ( 3-5mins of contactor clacking)
Left, no load, the delta will take DAYS to reach acceptable 20mV (Charger -auto off)
UNLESS, you drive vehicle (or supply load) and reduce SOC to ~ 98% where delta will be <20mV.
Which is standard behaviour for LiFePO4, ASFAIK. (With one cell lower IR, all the rest pretty similar)
Sad that I cannot get mean cell voltage unrested to >3.4V.
Did these observations when I got vehicle 10mnths ago, and have somewhat lost interest but still curious to another SESR owners reading re HV LV delta at 100%.

I drove an X-power a couple of days ago!!! OMG!

 

[Joningy]

When you are charging up to 100% charging the power consumption rate will be 2kW/7kW/11kW (depending on your charger supply). When the BMS is 'balancing' (after the battery has reached 100%) the battery will only be drawing 0.3kW. This might be for 30 mins or it might be for 2 hrs, depending on how much equalisation is required. As far as I know, you need to be watching the charging device app to see this happen. Once the balancing is complete the power draw will be zero. It would be great if there was an option in the MG app or on the dash display to see a live estimate of the cell equalisation, or maybe an alert when it was required.

And of course this equalisation only happens when you are charging from an AC supply, not a DC fast charger.

More info is available at EV Battery Cell Balancing - EV World

Thank you @wazmac, this is the most informative article I've read on car battery management and in particular 'balancing' or 'equalisation' as it is commonly referred to.
It is generally in line with my earlier post on the MG4 forum, and I'll re-post the excellent Australian article you kindly ferreted out. Great find!

See Equalisation charge - NMC battery (MG4 forum)​

 

[Joningy]

Mine is 2 years old; no idea if the last owner looked after it. I'll probably plug it in overnight

How did you get on @maskull with the Equalization charge.
I can't see if you've followed it up!

 

[maskull]

How did you get on @maskull with the Equalization charge.
I can't see if you've followed it up!

The only clue I get is that ,when I charge to the set percentage, the car is still accepting charge according to ISmart.
I assume this eqalization