Recent BMS update

[Mike]

Personally I think manufacturers will start to stop giving us battery pack size at some point in the future, like Tesla have done.

I don’t really care what the pack size is, however what I do care about is range. This is what Tesla quote.

What would be more useful would be ‘the car can do 120 miles in sub zero temperatures at 70mph up a steep hill!!’

MG are being proactive.

My previous car, a Nissan Leaf 40kWh suffered from #rapidgate from the day I collected it in March 2018. It was widely publicised. Unknown to us Nissan altered the BMS on new cars around September 2018, but didn’t release it to people who complained until February 2019.
It didn’t fix the problem, but helped it a bit. The problem with a Leaf is its passive air cooled battery, which is prone to overheating.

MG on the other hand have reacted very quickly to issues, some may say not quick enough, but they found a problem and fixed it and admitted it. I’m sure it takes time to find the fault, fix it, test it then roll it out to dealer.

Nissan never have admitted there is a problem with the Leaf! the best selling EV until recently...

 

[Lovemyev]

Nissan never have admitted there is a problem with the Leaf! the best selling EV until recently...

Lesson learnt !.
If you are not totally honest with your customers, they will vote with their feet and walk !.
Find it - Fix it !.

 

[jamesie]

Agree with all you are saying Cocijo.

MG through their dealers should be contacting all customers affected for a recall. Sounds like Chorley Motors are doing this which is good practice. It doesn't appear that other dealerships are following suit. MG should insist that they do.

I picked up my car in November 2020 so I am likely affected (inflicted!!). However, due to lockdown and particularly bad weather in the past week or two I haven't been able to determine if I have. What doesn't help is that we can't check the various software release(s) we have (other than OVMS users) to see either.

It's a poor situation for owners.

 

[Paulie68]

If that is the case then MG should recall all cars and complete the update shouldn’t they? It seems some have had their cars in service recently and not had the update.

Yes, I agree, MG's general running of its business here seems a little shambolic to be kind!. Dealers all seem to be doing thier own thing, some are excellent, but many are giving poor, or in some cases, downright incompetent service.

 

[JodyS21]

They aren’t reducing the range we have been told. Just reduced the top end voltage and the bottom end to keep useable battery capacity the same and hence the range the same.

If that is indeed true, as we hope to be the case, then yes the capacity available should be the same.
It would be nice if it could be proved however.
- It'd be nice if we didn't need to test these things & could just easily see them, unfortunately the trust in MG clearly isn't there currently.

Personally my car as per my calculations from the journey data & small bit remaining on the GOM, gives me a 39.56kWh usable battery....

 

[JodyS21]

Bear in mind aswell, that MG aren't actually doing anything wrong by reducing the voltage and range by approx 5% because the warranty on the car covers for a loss of 30% over 7 years.

That is a good point and I have no idea where legally owners would stand on this.
In theory MG could update our cars now to restrict the battery usage to say 35kWh, to "protect" the batteries, but say they're within their 30% over 7 years warranty.

 

[JodyS21]

Good points. I wonder if reducing the top end voltage also reduces the motor power output? It would wouldn’t it? That would mean the published power has also changed.

I'm not sure how the battery voltage relates to motor performance.

The motor is rated at 105kW from my bad memory. I don't know what voltage that is rated at though.
I'm wondering, does the power go through some voltage regulation before it hits the motor, therefore the voltage at which the motor is powered is always static. This then just comes down to the current that can be drawn from the battery pack when it is at the different voltages/SoC, if enough current can be drawn to supply the motor at it's full 105kW.

 

[Kithmo]

When I bought mine in July, with 6 miles on the odometer, the average m/kWh read 3.9 and the range fully charged was 163 on the GOM.
Am I right in thinking that means; 163/3.9 = 42 kWh capacity (approx) ?
Is that the way the GOM calculates the range, multiply the average m/kWh by 42, is is as simple as that ?

 

[JodyS21]

Realistically most owners - who don’t vacate forums like this one - will only have the limited information that is given them by their MG dealer. They will judge their ownership experience on how the car performs for them, and most I think will be very pleased with it. For this reason I can’t see a change in approach from MG in the short term anyway. I do however think that MG are asking for trouble if they supply for example a HV pack voltage meter - what real purpose does this achieve for the average owner other than to create anxiety over what it should or shouldn’t read? All of this stuff should just happen in the background - owners just want their cars to charge up and work as intended - not have to monitor battery voltages or complete equalisation after equalisation (I’m amazed at how tolerant owners are at diligently completing these tasks.). I’m sure other EV manufacturers tinker with their batteries and BMS systems post production and you never get to hear about it - if you provide customers with information like battery voltages then you must be prepared to meet the challenges that you will face when these change.

To me, what would make sense is to provide an actual figure of what usable capacity is remaining in the battery "tank".
After I'd fully charge, I'd expect to see this say probably 42.5. And when the car were to run out of juice for it to say 0.

The GOM is all very well, but it is based on a guess algorithm on how you're using the car.
In an ICE car, we have a dial of what's in the tank - which is what we use to know when to fill up etc. Surely we should have it on an EV car.
Yes, in a modern ICE car, the computer tells you MpG and estimated miles until empty, which is like our GOM. I rely on this in my ICE car rather than the tank capacity - But that is because it's many times more accurate than an EV GOM, as driving etc differently doesn't make anywhere near the difference in an ICE car as in an EV car.

 

[JodyS21]

When I bought mine in July, with 6 miles on the odometer, the average m/kWh read 3.9 and the range fully charged was 163 on the GOM.
Am I right in thinking that means; 163/3.9 = 42 kWh capacity (approx) ?
Is that the way the GOM calculates the range, multiply the average m/kWh by 42, is is as simple as that ?

Spot on, logically that is what it must do.

Your journey or accumulated data (don't know which), is the data the computer has to base your expected driving on. So literally it would multiple that m/kWh by the amount of capacity it thinks is available in the battery to use.
If you then switched on heating etc, it would alter the algorithm by a percentage I guess. Same with changing the mode.

Now, whether it is clever enough to remember what parts of the journey and m/kWh were on what mode setting, and apply this factor to the final GOM calculation based on the currently selected mode, I very much doubt MG have done that to be honest.

 

[AV2EV]

I purchased my car in March 20 and have the comfort 2 software added in May, but since then the car hasn’t been back to the dealer for any updates. My first service is due next week and I’m concerned that the new BMS update will still cause me problems, okay my car shouldn’t have any balancing issues, but do I have the right to say I don’t want it installed as my current BMS seems to be working fine, why did they look to update it anyway, what were they trying to accomplished with the version that went wrong. Do you have any advise on this matter?
MilesperKWH - Would be interested in you thoughts and comments as an MG dealer....

I'd recommend you skip the update. Had a lot of problems, the range dropped 80 km, constant warnings "Slow Charge the Vehicle", one cannot trust the numbers of remaining km at all. the other day it showed a "Low Charge" warning at 96 km...

 

[Mark Holmes]

I'd recommend you skip the update. Had a lot of problems, the range dropped 80 km, constant warnings "Slow Charge the Vehicle", one cannot trust the numbers of remaining km at all. the other day it showed a "Low Charge" warning at 96 km...

When did you have your BMS updated, was it prior to Jan 21?

 

[Cocijo]

Personally I think manufacturers will start to stop giving us battery pack size at some point in the future, like Tesla have done.

I don’t really care what the pack size is, however what I do care about is range. This is what Tesla quote.

What would be more useful would be ‘the car can do 120 miles in sub zero temperatures at 70mph up a steep hill!!’

MG are being proactive.

My previous car, a Nissan Leaf 40kWh suffered from #rapidgate from the day I collected it in March 2018. It was widely publicised. Unknown to us Nissan altered the BMS on new cars around September 2018, but didn’t release it to people who complained until February 2019.
It didn’t fix the problem, but helped it a bit. The problem with a Leaf is its passive air cooled battery, which is prone to overheating.

MG on the other hand have reacted very quickly to issues, some may say not quick enough, but they found a problem and fixed it and admitted it. I’m sure it takes time to find the fault, fix it, test it then roll it out to dealer.

Nissan never have admitted there is a problem with the Leaf! the best selling EV until recently...

I agree on the battery size point and I also have mentioned this in other posts. The problem with comparing with a company that has clearly been historically poor in this area (Nissan) is that there is not much of a standard to live up to. I would rather judge MG on how they treat their customers now and going forward. Are they being proactive or reactive? The problem is it’s so hard to tell without good software release notes and effective versioning and consistent customer communication. These are areas that most car companies will need to significantly improve as the EV era approaches.

 

[Cocijo]

Cheers Miles your response offers me much more confidence, thank you for taking the time to reply.

Have you made a decision on the update?

 

[Lovemyev]

My local dealer indicated to me that most of their updates are carried out as a direct request from the customer !.
Therefore, indicating if you don't ask, you don't get it done.
Looking like a case of not inviting trouble is their view !.
This could well be a common practice I think, because owners cars are being submitted for their annual service and leaving with NO updates being done !.
There has been evidence of this only this week.

 

[Cocijo]

There’s a pattern here I’m afraid. My MG dealer service manager has been helpful - but I still got this in response to software update questions
”In that case I would not load any other software as we would not know if this would cause any other problem so best left as it is”

 

[Mark Holmes]

Have you made a decision on the update?

I’m not sure to be honest, I trust Miles, but there still seem to be many with historical issues and I would like to see these criticisms be corrected first by this recent update. Once I see positive comments coming through I maybe willing to take the plunge.

 

[ging353]

I haven't had the BMS updates done to my car but after a full overnight charge it's showing 451 volts. Is that good or bad?

 

[Miles Roberts CG]

I haven't had the BMS updates done to my car but after a full overnight charge it's showing 451 volts. Is that good or bad?

Is that with all consumers (lights,heating/air con) switched off? As these things can all drag the voltage down by a couple of volts.

 

[Trevor]

My local dealer indicated to me that most of their updates are carried out as a direct request from the customer !.
Therefore, indicating if you don't ask, you don't get it done.
Looking like a case of not inviting trouble is their view !.
This could well be a common practice I think, because owners cars are being submitted for their annual service and leaving with NO updates being done !.
There has been evidence of this only this week.

I presented my car for 1st service beginning Nov and declined comfort update as I wasn't going to spend £140 (or maybe he said £114?) upgrading a lease car. This was the only software I was told was available. After service I asked if any error messages were logged on car computer as I had had several instances where "MG pilot quit" on me. They don't actually check log during service, and I was told to return vehicle if I wanted it investigated. On way home the pilot quit and I turned back, left car running and instructed technician to connect up whilst error code active. After a while I was told technician is loading new software which improves MG pilot. I must also return in a couple of weeks to get the wiring harness changed under recall (but was told it was to the passenger mirror, so who knows what was really installed...). I noticed no difference in GUI, but do believe pilot worked better. I was also able to charge with doors unlocked. After wiring harness changed, I noticed that the range was permanently displayed on dash (but not outside temperature), so they obviously did another software update. Then my range started deteriorating and the car went back in Jan, getting the new BMS. I also told them I was unhappy with the previous software update as the headlights would now randomly flash (very short flash, almost strobing)- I could see myself getting into a road rage incident, or someone turning in front of me thinking I was giving them right of way, and wanted to be able to permanently turn off auto-lights. To do this I guess I got the comfort update, as I now had temperature display and the quieter bongs. So, there is a way to get comfort update for free, as it's not just for comfort, but addresses safety concerns too. Now I'm trying to recover battery - have already risen from 429V to 440V. Next job is to get compensation for electricity bill, as I'm equilising through my cheap midnight to 5pm slot, and charging at a high cost below that. Easily costing me 3x running costs, plus inconvenience of also having to charge away from home so as to be able to return. I do love the car, but MG reputation taking a big hit in my books.