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I recently got battery protection upgrade on my MG ZS EV and the dealer said I should run some equalisation charges with the 3kw charger to improve the GoM range. I've been getting a bit confused with the manual and some of the threads when it comes to equilibration (I've never been asked to do it by the car but regularly charge to 100% on public chargers) can someone answer the following:
1) is battery equilibration the same as battery balancing?
2) can this be done with a 7kw public charger or does it gave to be through a 3kw 3-pin charger?
3) if so is there a benefit to doing it with the 3kw over a 7kw?

Thanks,
 

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Battery protection upgrade?

Is that how they're selling the latest BMS software to fix the shitpile they put out in Oct/November?

Anyhoos equilibriation/balancing is the same thing - the car will do it automatically at the end of an AC charge (3 or 7kW).

You know the car is on "balancing" when the MG logo stays on solid rather than pulsing - once the logo goes off, balancing is complete.
 

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1) is battery equilibration the same as battery balancing?
2) can this be done with a 7kw public charger or does it gave to be through a 3kw 3-pin charger?
3) if so is there a benefit to doing it with the 3kw over a 7kw?
1) yes
2) It doesn't really matter either way.
3) none
 
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Is that how they're selling the latest BMS software
Well apparently MG have reduced the Voltage of the pack to ensure longevity of the pack. Just waiting patiently for the justifications of 90% is the new 100%, or your range is less but its not less range its more accurate range and in fact more range. Sounds like MG have based their Post Truth "upgrades" modelling on Renault and their BMS fix.
 
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@Sandy. @Miles Roberts explained that range is unchanged. MG has just lowered the top end very slightly and lowered the bottom end very slightly so you should still get the ‘163 miles’ WTLP. That is all that really matters. That our range has not reduced.

My battery is now at 449V. The imbalance was 21mV last night. It may even get better over time. I am getting the expected range for -3°C to -1°C that I would expect at this time of year.
 

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Well apparently MG have reduced the Voltage of the pack to ensure longevity of the pack. Just waiting patiently for the justifications of 90% is the new 100%, or your range is less but its not less range its more accurate range and in fact more range. Sounds like MG have based their Post Truth "upgrades" modelling on Renault and their BMS fix.
I'm not unduly concerned by a slightly bigger buffer to protect battery life.

But the "44.5kWh" has always been a bit disingenuous as it's more like 40.5kWh usable.

Intrigued to see the "new" net capacity in due course.
 

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I'm not unduly concerned by a slightly bigger buffer to protect battery life.

But the "44.5kWh" has always been a bit disingenuous as it's more like 40.5kWh usable.

Intrigued to see the "new" net capacity in due course.
The gross always was 44.5kWh as per the label on the battery.

Usable size has never been officially quoted by MG since the car was launched.

It was around 3% at the top end and 6% at the bottom end according to the OVMS developers.
 

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But the "44.5kWh" has always been a bit disingenuous as it's more like 40.5kWh usable.
Bjorn Nyland (YouTube) who does a lot of various car testing reckoned it was around 42.5 kWh. Which gives 163 miles at around 3.8 m/kWh which is achievable summertime.
 
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Zoe Devotee
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That our range has not reduced.
Yet to be proven of course. Unless you've got multiple sources who've had the dodgy BMS and have now got a fully balanced pack to prove otherwise?

The gross always was 44.5kWh as per the label on the battery.

Usable size has never been officially quoted by MG since the car was launched.
Again if you go back to pre-release it was advertised as usable 44.5kWh. In fact many folk specifically asked if that was usable or raw capacity and time and again we were told usable..... which on delivery of the first cars became apparent it wasn't.

I really hope MG can pull this back and come out smelling of roses. I'd hate for the ZS to pull a Zoe when it comes to disingenuous BMS updates. As we already know MG have gone down the misinformation route on capacity, a la Nissan and latterly Renault.
 
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Again if you go back to pre-release it was advertised as usable 44.5kWh. In fact many folk specifically asked if that was usable or raw capacity and time and again we were told usable..... which on delivery of the first cars became apparent it wasn't.
ISTR being told it was 45.6kWh gross, 44.5kWh usable.

@Neilew There's no possibility from my testing it has 42.5kWh usable - with 9% of buffering suggested by OVMS that would mean c.46.7kWh gross.

I think Bjorn may have subsequently downgraded his estimated capacity from earlier testing but to be fair I haven't watched any of his stuff for 6 months or so.
 

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He YouTubed his databases a few days ago. I can't remember if battery sizes were included. I'll have a look later and see what he says.
 
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On this video he has the data charts showing, but you can't see the MG until around the 10 minute mark. @CasperStorm you were right (or maybe it's updated or summer/winter) it shows 40.8 usable.
 

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Bjorn’s Capacity numbers jump around due to the way he tests the cars. The MG has 4 different capacity readings in that dataset. With greater capacity showing in the summer when the battery is warmer. I forgot his explanation for this, but it’s how he measures the amount of charge taken out v what is put back in and then he does the math to give a usable capacity on that car, on that day.
 

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This agrees with the OVMS guys. Approx 9% buffer across top & bottom. They guess it’s about 40.5kWh useable, which I’ve been trying to tell you all for a while!!!!! :p
 
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I have just carried out another 8 hour balancing charge and my battery has dropped to 436v.. It gets the new BMS update this week and I have a question about how to correctly do the multiple balancing charges that are required to being the capacity back up to where it should be.
As this is going to take many weeks/months to resolve, I don't want to constantly charge the car at peak times (I currently drive approximately 400 miles per week so that will get relatively expensive). Will these ongoing balancing charges work if I plug the car in to allow it to do it's timed off peak charge (to replace the energy I use with my daily driving), then in the morning if I don't need the car (weekends etc) plug it in again and allow it to do an equalisation charge?
Or, does the equalisation charge need to be tagged onto the end of a standard charge (as in, one long charge instead of an off peak charge, then a separate equalisation charge)??

Thanks
Do not bother trying to equalise your battery if you have the duff BMS. it doesn’t do anything to help because it’s not equalising the battery.

Just wait until you have the new BMS, then start doing equalisation charges, which will probably take 12+ hours on top of charging the battery.
 
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