Battery SOH

[mgaz]

No it's in the UK so it's the nc type thanks not lfp
Can you ask for a copy of the read out for the battery check after main dealer service?

 

[Chrisdriving]

X power 18 months old 100% still.

 

[ReintjeWA]

No it's in the UK so it's the nc type thanks not lfp
Can you ask for a copy of the read out for the battery check after main dealer service?

It doesn’t work like that…

Which version of the MG4 do you have? Some have LFP batteries and other versions have NMC batteries.

 

[Martinonline]

My Trophy was declared as having a 95% SOH at its third service. Whereas at its second service it was 100% and at the first service was 99%.

So I treat the figures as estimates. I have not done a 10% to 100% charge for over 6 months and I could be convinced that such an action and the SOC when the SOH is measured affects the reading.

 

[mgaz]

Thanks it's the MG S5 EV trophy

 

[Tuareg]

X power 18 months old 100% still.

My Xpower was also 100% after my 1st service, after 12 months. The technician explained that it would be between 99.5% and 100% as it rounds up to the nearest %. So 99.4% would come out at 99%.

 

[ReintjeWA]

Thanks it's the MG S5 EV trophy

I looked it up but yeah you do have a NMC battery, so maybe the SOH reading is a little strange.

When is the last time you let the SOC go down below 10%, let it sit there for at least an hour, then charge it in one continuous go to 100% and let the cells balance, then let it sit for another hour? This will show the BMS exactly how much capacity the battery still has.

Have you noticed a difference in maximum range you get from the car?

There may be some more (specific) info on the MG S5 forum though.

 

[mgaz]

Many thanks I have never let it get below 20% since I have had it (6 months) but always used home 7kw charger, when main dealer serviced it their form from garage said 90% soc, though the dash was on 49%! And soh was 90%
Wondering if it was checked - I really have looked after the battery always letting it balance after charging etc
Disappointed if I have only 90% soh after a year

 

[gary333]

Have you tried running it down very low <10% and then charging to max in one session? Might be worth trying that. Although, if the dealers have just left it charging for months on end when it was new, might just be they caused premature wear.

 

[Mouss]

My Luxury (EU Trophy) built in February 2023, delivered in July 2023 :
SoH via Car Scanner since August 2024:

August: 99
September: 98.5
November: 98

2025
January: 97.8
March: 97.3
April: 96.6
May: 95.9
June: 95.4
July: 95.1
August: 94.9
September: 94.6 then 94.8
October: 94.5
November: 94.6
December: 94.5

And from January 2026 to the present, 94.5 to 94.2, passing through 95.6 in February

Biggest drop was S1 2025 (-3%)

 

[mgaz]

Have you tried running it down very low <10% and then charging to max in one session? Might be worth trying that. Although, if the dealers have just left it charging for months on end when it was new, might just be they caused premature wear.

Thank you I will try that next.

 

[MickeySw]

Is it LFP? I wouldn't worry about it if it is the LFP pack. Shows an initial drop and then levels out. Meanwhile no one notices any drop in range.

Same applies to NMC batteries, once SoH hits the mid 90s, degradation seems to slow down significantly?? See also post #30

 

[Mystralfire]

Trophy extended Range (74kwh) 2024, 42tkm soh 96,7%.
90% slow 11kw charging between 20-80%