Disappointing winter range

[Andy pandy]

I drive an MG4 LR and the range I am getting at the moment is disappointing. I know that in colder weather the range drops off but right now it seems excessive. The quoted range for this model is 281 and in the summer months it goes above 300. At the moment it's dropped to 163 on 100% battery. On any longish trips the range is limiting.
Anyone else got comments on this subject?

 

[Griffian]

On very cold days when I first set off, I get about 2m per kWh increasing to about 3m later. With a 77 kW battery that's between 154m and 231m.. In summer, we can get towards 4.5m, or 340m on a full charge.

 

[jpk]

I drive an MG4 LR and the range I am getting at the moment is disappointing. I know that in colder weather the range drops off but right now it seems excessive. The quoted range for this model is 281 and in the summer months it goes above 300. At the moment it's dropped to 163 on 100% battery. On any longish trips the range is limiting.
Anyone else got comments on this subject?


View attachment 33817

I have to drive a bit more conservatively when it's this cold, mines a 64Kwh trophy, and I'm getting just shy of 200 miles range in these temps. If you think our range is disappointing in these temps you wouldn't want the standard range with the lfp pack

 

[DannySB1]

I have a Trophy LR and I agree, during these really cold stretches in winter the range drop off can be quite alarming. I try to drive as conservatively as possible but even still I'm probably struggling to hit 130-150 miles on an 80% charge at the moment.

HVAC is going to be one of the biggest culprits, sitting in the car earlier for 35 mins with the heat on drained the battery 2%, and that was stationary!

Fortunately I only really do city driving so it's not a huge deal for me, but when you talk about your car to other people it does tend to draw out a giggle or two. Hopefully EVs can improve in this area in the future.

 

[Martinonline]

@Andy pandy, have you calibrated your BMS in the past? A less than 10% to 100% charge plus balance. My Trophy is indicating ~ 200 miles at the moment.

 

[Andy pandy]

@Andy pandy, have you calibrated your BMS in the past? A less than 10% to 100% charge plus balance. My Trophy is indicating ~ 200 miles at the moment.

Hi Martinonline
Not really sure how to calibrate the BMS. Would appreciate info on how to do that plus balance.

 

[EvTek23]

On my last charge to 80% on 7th Jan (which also performed a balance) indicated 161 mls on the display. Mine is a Trophy LR.

 

[webhiker]

On my last charge to 80% on 7th Jan (which also performed a balance) indicated 161 mls on the display. Mine is a Trophy LR.

How did you make it do a balance at 80%?
According to manual it only balances in the hours after 100%?

 

[dsimpkins]

Also getting around 200 miles at the moment on a SE LR. MOst of my driving is commuting for work, about 8 miles each way, which means my miles/kWh is about 2.5/2.6. Longer journeys in this weather it gets up in the high threes.

Preheating the car to defrost it in the morning also effects the GOM reading.

 

[Jomarkh]

Hi Martinonline
Not really sure how to calibrate the BMS. Would appreciate info on how to do that plus balance.

There a few threads on this and it depends on your battery chemistry if it can charge and different SOC or just when at 100%. Different battery chemistrys also react differently to the cold. My NMC can loose anything between 25-35% range in the winter.

 

[EvTek23]

How did you make it do a balance at 80%?
According to manual it only balances in the hours after 100%?

I believe they call this phase "equalisation" When it gets to 80% you see the charging power dropping off, and eventually ending up pulsing every few seconds for about half an hour or so before the charge is finished, rather than terminating the charge abruptly when it reaches 80%. Its the same for a 100% SOC too.

 

[Coulomb]

I believe they call this phase "equalisation"

I like to reserve the term "equalisation" for the process of brutally overcharging flooded lead acid batteries, with later replacement of the water lost through gassing. No naked flames during this process!

Obviously, you can't use this process with sealed lead acid, and certainly not with any kind of lithium battery.

When it gets to 80% you see the charging power dropping off,...

I've recently noticed this too. I think that this removes most of the need for charging to 100% every month or two, assuming that you regularly charge to 80%.

In fact, I suspect that charging to 100% may undo a small part of the balancing done at 80%. The cells will never be perfectly the same total capacity, so balancing at 80% will "line them up" slightly differently to when at 100%.

Overall though, balancing at 80% is still a good thing, and I'm glad that the MG4 does it.

 

[Martinonline]

Balancing had been seen at levels less than 100%. See images below from @GrayCat and @sparc00 :

 

[Martinonline]

@Andypandy, you have an NMC battery so it will balance at levels lower than 100%. Balancing involves charging on AC until the car declares it is no longer charging having reached the set level. Note that just reaching the set level is not good enough, you must wait until the port lights (if working) go out or the car/app declares charging finished. Balancing can be assumed to be occuring if the estimated end time keeps moving in sync with real time and the consumed power goes between 0.0kW and a higher level, eg 3kW.

Calibrating the BMS involves running the battery down to below 10%, waiting an hour or so (recommended by some), then fully charging + balancing to 100% on an AC charger. See the Manual extract below:


Note: what you see on the car's screens is an 'guestimate' of the range. Your real range depends on a number of factors. You cannot rely on scaling up from a percentage range to the 100% range. A better estimate may be obtained by multiplying the accumulated miles/kWh figure by your battery size once that figure has stabilised on a journey.

 

[Andy pandy]

@Andypandy, you have an NMC battery so it will balance at levels lower than 100%. Balancing involves charging on AC until the car declares it is no longer charging having reached the set level. Note that just reaching the set level is not good enough, you must wait until the port lights (if working) go out or the car/app declares charging finished. Balancing can be assumed to be occuring if the estimated end time keeps moving in sync with real time and the consumed power goes between 0.0kW and a higher level, eg 3kW.

Calibrating the BMS involves running the battery down to below 10%, waiting an hour or so (recommended by some), then fully charging + balancing to 100% on an AC charger. See the Manual extract below:

View attachment 33837
Note: what you see on the car's screens is an 'guestimate' of the range. Your real range depends on a number of factors. You cannot rely on scaling up from a percentage range to the 100% range. A better estimate may be obtained by multiplying the accumulated miles/kWh figure by your battery size once that figure has stabilised on a journey.

Martinonline
Thanks for the info, it's really helpful. I'll try calibrating as you have explained.

 

[Coulomb]

Balancing had been seen at levels less than 100%. See images below...

Oh, wow! I don't recall seeing the display actually mention balancing. But I'm usually not in the car when balancing happens.

It would be nice if the iSmart app mentioned this as well.

you have an NMC battery so it will balance at levels lower than 100%.

Oh, yes; balancing an LFP battery can realistically only happen at 100% SoC, or very near 100%.

 

[BingBong]

It happens on all EVs, but especially at EVs like ours that doesn't have heat pump and generate heat with the A/C.

 

[Lord Randall]

I really don't get why UK mg4 is missing heatpump. It makes no sense at all.
EU one get it on the luxury/trophy/xpower specs. And when it reach the plateau, the drop in consumption is huge.

 

[Tight Git]

I really don't get why UK mg4 is missing heatpump. It makes no sense at all.
EU one get it on the luxury/trophy/xpower specs. And when it reach the plateau, the drop in consumption is huge.

Because it would add about £1000 to the cost and would only be useful a small part of the year.

MG UK will have decided where they want to save money so decided to not spec one for the UK

 

[Slipstream]

On my last charge to 80% on 7th Jan (which also performed a balance) indicated 161 mls on the display. Mine is a Trophy LR.

You can't do a balance till the battery is 100%