Thanks.
I've added to the spreadsheet.
I'm really surprised they didn't update your BMS at the service. I thought that this was part of having a service - a big reason why should have it done at an MG dealer rather than a cheaper independent etc.
What date in Feb was the service? as another newer BMS came out in Feb (earliest someone got the newer BMS is 11/2).
Decision for you really, I think if it were me, I'd want a newer (must be better) one installed.
We believe the SoC is the percentage of a full 44.5kWh battery charge, the BMS stops it being charged to the full amount for preservation purposes. The data must be manipulated to show on the dash when charging that it gets to "100%".
SoH, not sure yet what this means/how it's calculated.
It'll be very interesting to see your fully charged & balanced data. (Take data with car on but brake pedal not pressed so HV battery is off)
Thanks for this.
Yes, I was umming and ahhing about whether to specifically request BMS and other software updates at the first service and assumed that if they were important, that they would be done as a matter of course.
I decided against specifically asking for these to be done as at the time there was still (in my opinion) not a clear picture on the impact of the faulty BMS software and whether the more recent updates rectifying the problem were themselves bug free. I am nervous to say this but, to date, the car has been flawless in terms of performance, range, drive-ability, etc and I didn't see any new functionality from the updates that warranted specifically requesting updating the other bit, not like me as I am usually an early adopter.
It is interesting to see that only the comfort update and DCDC and ECC updates have been undertaken. This being the first time I get to see what has and hasn't been done proved interesting but I still don't feel compelled to get the entire car updated at this stage.
It will be interesting to see the impact of the recent updates to the BMS in terms of the SoH evolution over time, perhaps that is one of the key benefits of the more recent updates and the move to shifting the upper (and presumably lower) voltage limits of the operation of the battery.
Will re-post when I get some data of the charged car and will follow your advice on the conditions relating to how to capture this. Thanks for this effort and for the spreadsheet, it has been eye opening to see the range of software variants (and combinations of these) around. Must be a nightmare to keep track of.
My feeling around SoH and SoC is that however it is done, (SoC/100) x (SoH/100) 44.5 = Available Capacity. You either always report SoC between 0 and 100 regardless of the "full" voltage and then decrease SoH as available capacity decreases with age (makes most sense to me) OR do the opposite, keep SoH constant at 100% (Why have it in this case?) and reduce and report the "full" voltage or SoC as the available battery voltage decreases. However, it I guess that batteries are complex things and it is almost certain that capacity degrades without voltage limits changing.
I love seeing the battery voltage and current but one of the dangers is that it can overly simplify how batteries operate and age, leading to disappointed customers/drivers in some cases. I wonder if it is a way of shielding the available capacity of the battery from the user making warranty claims not impossible but more difficult as the company learn about deploying these cars in a countries with a different set of climates.