SOH 98.31 after 19889 miles

[Mark Holmes]

Dear all,
Please see the attached for your information about battery degradation after 19889 miles, that said my battery didn’t fully balance before being unplugged due to needing to get on the road, but it appears I’ve only lost 3 miles which I feel is very good.
All trip info reset and volt at 449 as expected.
See pictures

 

[Pepe]

Hi Mark,

Many thanks for the information. Can you say what app and connector you use to be able to read the data like this? Many thanks. Doug (Australia).

 

[Mark Holmes]

Hi Mark,

Many thanks for the information. Can you say what app and connector you use to be able to read the data like this? Many thanks. Doug (Australia).

I will look to post again tomorrow’s, but it’s the one mentioned within the subject matter within this forum under OBD11

 

[JodyS21]

Dear all,
Please see the attached for your information about battery degradation after 19889 miles, that said my battery didn’t fully balance before being unplugged due to needing to get on the road, but it appears I’ve only lost 3 miles which I feel is very good.
All trip info reset and volt at 449 as expected.
See pictures

It finally happened then.
I guess can't really complain about loosing 3 miles range after 20k miles, let's hope it doesn't carry on going down any quicker and you get another 20k miles before you loose another 3 miles.

BTW. 98.31% of 163 = 160.25, so your reset GOM 160miles vs 163miles adds up.

 

[Mark Holmes]

It finally happened then.
I guess can't really complain about loosing 3 miles range after 20k miles, let's hope it doesn't carry on going down any quicker and you get another 20k miles before you loose another 3 miles.

BTW. 98.31% of 163 = 160.25, so your reset GOM 160miles vs 163miles adds up.

I’m going to check this again today, ensuring a full balance has been completed

 

[Mark Holmes]

I’m going to check this again today, ensuring a full balance has been completed

159 miles shown on the GOM this morning with everything reset and SOH has dropped to 97.2, I will continue to monitor this……

 

[JodyS21]

159 miles shown on the GOM this morning with everything reset and SOH has dropped to 97.2, I will continue to monitor this……

WTF, you've lost more since last night, I don't like the sound of that.

So, 97.2% of 163 = 158.44miles

 

[Mark Holmes]

WTF, you've lost more since last night, I don't like the sound of that.

So, 97.2% of 163 = 158.44miles

I will be keeping a close eye on this over the coming months…

 

[JodyS21]

I read an article this morning that suggests that battery SOH will not continue at the same rate, hopefully it's true...

EV Battery Health Insights: Data From 10,000 Cars | Geotab

Geotab research reveals how EV batteries can last 20+ years with proper care. Learn key insights and best practices to maximize EV battery life and performance.

www.geotab.com

 

[Cocijo]

My car can show varying predicted ranges - albeit slight (all after a full reset and under the same conditions - i.e. fully charged and balanced ancillary components switched off etc) which is weird. I can get between 159 and 162 miles in N mode - i’m not sure why there is a variation

 

[JodyS21]

My car can show varying predicted ranges - albeit slight (all after a full reset and under the same conditions - i.e. fully charged and balanced ancillary components switched off etc) which is weird. I can get between 159 and 162 miles in N mode - i’m not sure why there is a variation

That’s a bit odd.
Mine shows 163miles (N3) fully off/reset after a full charge and full balance 99% of the time, I have seen it show 162 a couple of times but generally that’s been when I’ve checked it after it had been sat for a while/a day after it had finished charging.
That’s since January so over different ambient temperatures too.
I do like seeing that mines consistent but given it is a guess o meter I wouldn’t worry too much about that slight variation.

 

[Cocijo]

I’m not too concerned. I’ve never seen 163miles!

 

[Lovemyev]

I don't really worry about the small reported fluctuations on the GOM from charge to charge to be honest.
It's only a "Prediction" anyway.
On my previous PHEV I have seen the GOM prediction fluctuate from morning to afternoon, without the car even moving an inch !.
On a couple of occasions while cleaning the car first thing in the morning, by opening the drivers door, it would display a predicted range of say 28 miles on the GOM.
A nice morning regarding the weather, but a little dull.
By 1.30pm with a big improvement in the weather ( very sunny now ) opening the door again and it displays a range of 29 miles now !.
The car has not moved an inch and I have gained 1 mile of range - go figure !.
A good example of how the ambient temp influences the GOM.
I have witnessed this on more than one occasion.
I have learnt over the four years of ownership of the PHEV - to take this figure with a large pinch of salt.
Others owners had reported the same condition.
The best advice I was offered was this :-
"Don't get paranoid and stress over it, instead just drive and enjoy the car".
I was fine after this !.

 

[Alan5]

My battery SOH has been slowly dropping since April it was 98.93 on the 7th June , I have decided not to worry about it and have been charging the battery fully recently using the granny charger (which I use 95%of the time) as I have been doing longer journey's in the nice weather . Checked the SOH on the 11th June after a full charge and it is now showing 98.98 it's gone back up ? My car is still on the original BMS and still charging to 97% 162 miles in N , next month it's booked in for the 2nd year service so will be interesting to see if they advise a BMS update.

 

[Cocijo]

How many miles have you covered?

 

[Alan5]

How many miles have you covered?

11800 miles

 

[Lovemyev]

My battery SOH has been slowly dropping since April it was 98.93 on the 7th June , I have decided not to worry about it and have been charging the battery fully recently using the granny charger (which I use 95%of the time) as I have been doing longer journey's in the nice weather . Checked the SOH on the 11th June after a full charge and it is now showing 98.98 it's gone back up ? My car is still on the original BMS and still charging to 97% 162 miles in N , next month it's booked in for the 2nd year service so will be interesting to see if they advise a BMS update.

I think MG suggests that a HV balance of the pack, should be carried out at least once a month to help keep the cells balanced correctly.
In most circumstances, I only carry out a charge to a level that will suit our needs.
If I have above 100 miles of range, then I am happy to roll with that for local day to day stuff.
About once a week, we will make at least ONE pleasure trip that is very likely be over a 100 miles.
Last week we did a “There and Back” journey of around 130 actual miles on the same charge, and arrived home with a predicted range remaining of 60 miles.
For these type of trips, I am conducting a full charge and balance on a cheaper over night tariff.
I also like to “Zero” the accumulative trip meter on the car before starting out also.
As these longer journeys are possible now, they warrant a full charge and therefore the car gets it’s weekly balancing session as a bonus.
I have absolutely NO idea ?‍ what my HV battery SOH is right now, and this may sound a little crazy.
But the car is now 18 months old and covered over 12,000 miles.
When I consider we have covered this amount of mileage and been through two lengthy lock downs in Wales, it is a lot more mileage than we did in our previous car !.
EV driving is pretty addictive and a LOT more affordable than even my previous PHEV.
The car HAS received the latest BMS update on the 15th Jan and was likely to be one of first privately owned cars that got it.
Long story, but the car was given the update as part of an instruction from MG Tech after the car had a complete melt down at the dealers while in for its first service and drivers door wiring harness replacement.
I do feel that I can trust the car to makes the longer trips and that the reported range on the GOM is pretty accurate.
We tend to get the amber low range warning at around the 35 - 40 mile mark.
Just for the record, I always drive in the default mode of Normal and Regen level 3.
I have a EV friendly electricity plan that gives us cheap rate of 8p all weekend.
Yesterday ( Sunday ) I charged to roughly 150 miles of range.
This morning ( Monday ) my wife has suggested a trip that will be around 120 miles.
I feel more than comfortable to accommodate this request with regards to the available range in the car.

 

[JodyS21]

I think MG suggests that a HV balance of the pack, should be carried out at least once a month to help keep the cells balanced correctly.
In most circumstances, I only carry out a charge to a level that will suit our needs.
If I have above 100 miles of range, then I am happy to roll with that for local day to day stuff.
About once a week, we will make at least ONE pleasure trip that is very likely be over a 100 miles.
Last week we did a “There and Back” journey of around 130 actual miles on the same charge, and arrived home with a predicted range remaining of 60 miles.
For these type of trips, I am conducting a full charge and balance on a cheaper over night tariff.
I also like to “Zero” the accumulative trip meter on the car before starting out also.
As these longer journeys are possible now, they warrant a full charge and therefore the car gets it’s weekly balancing session as a bonus.
I have absolutely NO idea ?‍ what my HV battery SOH is right now, and this may sound a little crazy.
But the car is now 18 months old and covered over 12,000 miles.
When I consider we have covered this amount of mileage and been through two lengthy lock downs in Wales, it is a lot more mileage than we did in our previous car !.
EV driving is pretty addictive and a LOT more affordable than even my previous PHEV.
The car HAS received the latest BMS update on the 15th Jan and was likely to be one of first privately owned cars that got it.
Long story, but the car was given the update as part of an instruction from MG Tech after the car had a complete melt down at the dealers while in for its first service and drivers door wiring harness replacement.
I do feel that I can trust the car to makes the longer trips and that the reported range on the GOM is pretty accurate.
We tend to get the amber low range warning at around the 35 - 40 mile mark.
Just for the record, I always drive in the default mode of Normal and Regen level 3.
I have a EV friendly electricity plan that gives us cheap rate of 8p all weekend.
Yesterday ( Sunday ) I charged to roughly 150 miles of range.
This morning ( Monday ) my wife has suggested a trip that will be around 120 miles.
I feel more than comfortable to accommodate this request with regards to the available range in the car.

I assume after a full charge & balance, resetting trips, with everything off, taking the GOM reading effectively gives an indication of what the SOH% is.
To confirm, take the GOM e.g. 160 and divide it by 163 (x100) and you'll pretty much get the SOH%.
Someone gave a couple of data points for this, they provided their full GOM and SOH% on a couple of occasions and they calculated out consistently.

I think in the current UK temperatures, I would (the wife wouldn't) just about risk a trip of 120miles after a charge with a reset trip showing 150miles, would def not be going above 65mph max though & def in E3 mode. 120miles could easily turn into 140+ miles with any detours/missed turnings etc. I'd feel a lot more confident knowing I had a 100% charge though.

 

[Lovemyev]

I assume after a full charge & balance, resetting trips, with everything off, taking the GOM reading effectively gives an indication of what the SOH% is.
To confirm, take the GOM e.g. 160 and divide it by 163 (x100) and you'll pretty much get the SOH%.
Someone gave a couple of data points for this, they provided their full GOM and SOH% on a couple of occasions and they calculated out consistently.

I think in the current UK temperatures, I would (the wife wouldn't) just about risk a trip of 120miles after a charge with a reset trip showing 150miles, would def not be going above 65mph max though & def in E3 mode. 120miles could easily turn into 140+ miles with any detours/missed turnings etc. I'd feel a lot more confident knowing I had a 100% charge though.

I totally agree with all of your points.
Thanks for the tip on working out your SOH of your battery !.
See, I tend not to bother using Eco mode myself, I find because I have used the default normal mode from pretty much day one, I have a fairly good understanding of how the car is performing.
Flicking to Eco increases the range alright, but it does not increase the actual distance you can travel I don’t think ?.
70 Mph work is a big contributor to consuming your range and HVAC use is the same I find.
Natural ventilation from the sun roof is my preferred option.

 

[JodyS21]

You raise an interesting point, my wife asked me just the other day, what is more efficient using aircon or having the window/sunroof open.
I couldn’t answer it, as I doubt there’s much in it.
Aircon only seems to use an amp or so (it’s the heater that really sucks the life out of the battery), but open windows/aircon mess up the aerodynamics & causes drag.
I wonder if something like over 50mph the aircon is more efficient and at lower speeds opening the window/sunroof is.

In theory you can get the same distance from eco & normal, but you would need to always be very conscious of how gentle you are on the accelerator pedal. I just can’t do it, I find myself unconsciously using more power on the dial in normal mode!