Losing charge overnight

[McX]

Hi all,

My wife has just bought herself a MG ZS short range, 2022 model.

She is reporting that it is losing anywhere between 9 and 15 miles of charge overnight, a percent or two.

I've checked all I can think of any everything appears to be turned off so not sure what may be causing this battery drain?

Anything obvious that I might be missing or can anyone give me some pointers?

Many thanks!

McX

 

[Eclectic]

Its probably just temperature drop overnight, it makes a noticeable difference to the battery.

 

[Alb]

Charge isn't measured in miles so it probably hasn't changed at all.
Your car is just taking a different guess at what the range may be based on the prevailing conditions.

 

[Jomarkh]

If you reset all the trip counters every night does it still lose a few miles.
Why do you think it has a 'short range' and not a 'standard range'?

 

[Kithmo]

Does she drive in ECO mode ?
If she ends her journey in ECO when she starts the car in the morning the car will be in Normal mode and showing 10-15 miles less on the GOM.

 

[MichaelJHunt]

The SR version of the ZS requires that you charge to 100% when ever you charge the car. This allows the BMS to more accurately determine the SOC %.

If not regularly charged to 100% SOC the BMS will falsely report the active SOC.

The range figure reported is just a guess and will vary on driving style. As mentioned by @Kithmo above, reported range will vary depending on active driving mode: ECO, NORMAL or SPORT.

The SOC (State Of Charge) % is the figure to look at.

 

[McX]

Thanks for your comments all. In my OP I mentioned both miles remaining and percentage charge. I've a Tesla Model 3 which does not 'lose charge' overnight which prompted by question on this forum.

2 days running now the car has not moved, but we've checked the % remaining and it has decreased by 2% each night. Battery was 100%, but now 96%.

My wives driving style can be described as 'enthuastic' and is always in NORMAL mode.

 

[drmcw]

I'd expect all EVs to behave like the Tesla. Losing 2% SOC in 24 hours indicates either it's not shut down or there's an issue. The cars'd never make it over from china in the boats if they behaved like that!

 

[MichaelJHunt]

I'd expect all EVs to behave like the Tesla. Losing 2% SOC in 24 hours indicates either it's not shut down or there's an issue. The cars'd never make it over from china in the boats if they behaved like that!

Advise for Tesla owners who all suffer from “Vampire Drain”….

How to reduce battery drain (aka vampire drain) when you leave your Tesla parked up (Phantom Drain) - Tesla Owners UK

In an ideal situation, you should leave your car plugged in if you plan to leave it for extended periods of time (e.g. more than a few days), however, that isn’t always possible so this page will help you reduce your risk of running out.

teslaowners.org.uk

And if you use “Sentry Mode” you can expect a flat battery in around 10 days from a full battery.

 

[drmcw]

I knew that sentry mode in a Tesla was "thirsty" but didn't realise they had other thirsty options. Perhaps I should've said that I'd expect all EV's to behave better than a Tesla Still think that consistently seeing a drop in SOC overnight if everything is shutdown is not "normal".

 

[drmcw]

Was just going to mention that keeping the SOC at 100% for a couple of days is not the best idea when I read the original post and it's the SR version. Wondering if the LFP chemistry of the SR model may well account for the change?

 

[DebbieP64]

Was just going to mention that keeping the SOC at 100% for a couple of days is not the best idea when I read the original post and it's the SR version. Wondering if the LFP chemistry of the SR model may well account for the change?

Thanks for your comments all. In my OP I mentioned both miles remaining and percentage charge. I've a Tesla Model 3 which does not 'lose charge' overnight which prompted by question on this forum.

2 days running now the car has not moved, but we've checked the % remaining and it has decreased by 2% each night. Battery was 100%, but now 96%.

My wives driving style can be described as 'enthuastic' and is always in NORMAL mode.

My SR 22 plate did this. I took it back to garage. They said there was updates etc. whatever they did sorted it out as far as I could see. Only had the car for another week and swapped for LR

 

[Tim Falkiner]

Hi all,

My wife has just bought herself a MG ZS short range, 2022 model.

She is reporting that it is losing anywhere between 9 and 15 miles of charge overnight, a percent or two.

I've checked all I can think of any everything appears to be turned off so not sure what may be causing this battery drain?

Anything obvious that I might be missing or can anyone give me some pointers?

Many thanks!

McX

I have had a short range MG ZS EV for about fourteen months. I only fully charge it about every month to balance the battery. I have a Zappi charger which charges it at 6.8 kW which effectively gives me 40 km range per hour charging. So I let the car get down to about 100 km range and charge it for 2.5 hours on the Zappi to bring it up to 200 km range. I just set my iphone to give me an alarm. This means the battery range stays between about 50% and 85% and this should result in very little battery degradation. When you say the car loses between 9 and 15 miles of charge overnight is this every night or just when you have charged it to full?

 

[N2STY]

I have had a short range MG ZS EV

Some people will get confused by this you have a gen/mk 1 ev normally when someone says SR (short/standard range) there referring to gen/mk 2 (face lift) with a completely different battery that really needs 100% to keep BMS working efficiently

 

[Tim Falkiner]

Some people will get confused by this you have a gen/mk 1 ev normally when someone says SR (short/standard range) there referring to gen/mk 2 (face lift) with a completely different battery that really needs 100% to keep BMS working efficiently

Fourteen months and I am obsolete.

 

[drmcw]

Fourteen months and I am obsolete.

Count yourself lucky, with the delays to Mk2 deliveries then most will be obsolete before the car arrives!

 

[Tim Falkiner]

Absolutum, obsoletum - if it works, it's out of date. (Dedication to Stafford Beer, Brain of the Firm 2nd ed.)

 

[Kithmo]

Count yourself lucky, with the delays to Mk2 deliveries then most will be obsolete before the car arrives!

I wonder if they will get their cars before the mk3 comes out.

 

[MichaelJHunt]

I wonder if they will get their cars before the mk3 comes out.

I’ve just ordered the face-lifted MG5 LR. Expected delivery in October - see how that pans out