MG4 Range

Michael1982 said:

I disagree, i could regularly beat the claimed MPG in my BMW, especially on a long motorway run doing the speed limit and not sitting at 50mph hiding behind an HGV for improved wind resistance, apparently thats how i must drive to make my EV's get closer to its claimed range

My 4 is doing 2 miles per kwh and its doesnt really make a difference how i drive

I fully understand all these things and accept them, but i was expecting a bit of a drop off in range, i was not expecting to lose most of it or needing to drive at 20 mph everywhere i go to be able to achieve the claimed range

Some people should not have a licence, driving way too slow is as dangerous as driving way to fast

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A long motorway drive sitting in 6th gear isn’t what mpg averages are calculated on either. They’re based on cycles of mixed road and speed driving. Drive round town in stop start traffic and your 2 miles per kWh will drastically improve. You won’t have moved very far but it will have been efficient.

It feels like you just want to disagree about everything. If you really don’t like the car that much then trade it in and mark it up to a bad experience.

Michael1982 said:

is that against the law or a sign or being disrespectful???

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I don’t have a problem with it, I see it just as your style, like an accent in question-mark form.

Michael1982 said:

is that against the law or a sign or being disrespectful???

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I think it's clear that people here are trying to help you, whether or not you are deemed disrespectful. Ultimately if your vehicle doesn't fit within the norm that people have been advising for this cold period, then you have to determine if your vehicle has an issue and whether you need to take it back to your dealer. I see you have it booked in, so I'm sure we're all hopeful that you find a solution.

Please remember that we are all trying to provide the best help we can, and getting angry with any responses because it doesn't "cure" your issue will not help anyone. As someone I think has already pointed out, your issue is with MG and not with anyone on here. I hope you obtain a successful outcome.

Michael1982 said:

is that against the law or a sign or being disrespectful???

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It’s against the “Totally Wasteful Excessive Repetitive Punctuation act 2022”. Penalties can be severe. Seriously though, I’m sure you will use whatever communication style you like and it’s obvious you’ll pay no mind to how you come across. Good luck with resolving your issue.

tsedge said:

To 100%? That was the crucial part of my question.

LFP requires regular charging to 100% and battery pre-heating in very cold weather. Otherwise you can get exceptional range losses.

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With danger of dragging this thread back on track - Does the 100% have to be from a low % or does it just need to hit that 100%? Also, does the charge rate matter with balancing? I'm currently only slow charging at 1.8kw at the moment. I am seeing the range to be about 1 mile per % of charge and wondering if never charging to 100% is making this reading inaccurate.

Crawfyp said:

It’s against the “Totally Wasteful Excessive Repetitive Punctuation act 2022”. Penalties can be severe. Seriously though, I’m sure you will use whatever communication style you like and it’s obvious you’ll pay no mind to how you come across. Good luck with resolving your issue.

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It's like when people come to a forum and use txt spk - using a forum like instant messaging. Or post a wall of text using hardly any punctuation.

Actions which may annoy some people and so limit the breadth of help they may receive.

MarkSponge said:

With danger of dragging this thread back on track - Does the 100% have to be from a low % or does it just need to hit that 100%? Also, does the charge rate matter with balancing? I'm currently only slow charging at 1.8kw at the moment. I am seeing the range to be about 1 mile per % of charge and wondering if never charging to 100% is making this reading inaccurate.

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Just has to reach 100% and slower charging is generally better for balancing. If it isn't reaching 100% LFP can quite rapidly lose track of the battery state of charge and may enforce a defensive/conservative mode on the battery. If it is out of balance, it won't be able to predict range accurately.

Edit: 1 mile per % with 51kWh battery is about 2 miles per kWh. That's low as an average, many people achieve more like 3-4 but in winter it will be less. What is your typical journey mix?

tsedge said:

Just has to reach 100% and slower charging is generally better for balancing. If it isn't reaching 100% LFP can quite rapidly lose track of the battery state of charge and may enforce a defensive/conservative mode on the battery. If it is out of balance, it won't be able to predict range accurately.

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Could that be why a couple of owners are having restricted speed and or lower than average miles/kWh because the battery hasn't had a chance to balance properly?

Ian Key said:

Could that be why a couple of owners are having restricted speed and or lower than average miles/kWh because the battery hasn't had a chance to balance properly?

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Yes. I think it is the most common case with LFP because people don't know about it and dealers are terrible at communicating. NMC generally needs less balancing and it is inherently easier for the BMS to track it, but even there if you don't do a 100% charge periodically, you can get problems.

Having only a granny charger can be a tell-tale because then you might never reach 100% if you drive every day, eventually triggering this problem.

Of course, it is much better if the car detects and proactively warns about these problems. Haven't seen much evidence that the MG4 does this.

Edit: The general recommendation for LFP seems to be to 100% charge once a week.

tsedge said:

Yes. I think it is the most common case with LFP because people don't know about it and dealers are terrible at communicating. NMC generally needs less balancing and it is inherently easier for the BMS to track it, but even there if you don't do a 100% charge periodically, you can get problems.

Having only a granny charger can be a tell-tale because then you might never reach 100% if you drive every day, eventually triggering this problem.

Of course, it is much better if the car detects and proactively warns about these problems. Haven't seen much evidence that the MG4 does this.

Edit: The general recommendation for LFP seems to be to 100% charge once a week.

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That's right LFP has quite a flat voltage profile except at the extremes of its usable output range where as NMC and NCA batteries have a gradual rise and fall.

LFP charge and discharge profile attached for a generic LFP battery

Well all that kept me from Strictly it takes Two. You have no idea how much I appreciate
that, thanks. Now what we're we talking about again..oh yes range..my current ev is down about 15% this morning....but only because Tesco down the road (2 minutes at most) gave me 15 minutes free charge whilst every combination of heating was blasting away to save battery before my longer drive and that definitely helped maintain range. Oh and it warmed up my drivers door lock which would not lock after opening this morning...and the folding mirrors opened but would not go back...the joys of this freezing weather eh

tsedge said:

Just has to reach 100% and slower charging is generally better for balancing. If it isn't reaching 100% LFP can quite rapidly lose track of the battery state of charge and may enforce a defensive/conservative mode on the battery. If it is out of balance, it won't be able to predict range accurately.

Edit: 1 mile per % with 51kWh battery is about 2 miles per kWh. That's low as an average, many people achieve more like 3-4 but in winter it will be less. What is your typical journey mix?

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I give more details in post 87 in this thread but basically I preheat cabin for 10 minutes (off charge) then do 2-3 mile trips with heat blasting and normal driving mode. I do this trip a couple of times per day and the dash says 2 kwhpm.

I did try eco as a test and got 3 kwhpm but realistically I’m too lazy to change it every time

I don't know how to reply to this but somehow feel like I should. I'm sympathetic to Michael's points even if he could maybe tone down the confrontation a bit.

He's obviously got a problem with the loss of power which should be looked at by the dealer.

Let's face it, EV's are not great in winter and the MG4 seems particularly bad. People like me might say that the benefits of pre-heat etc. outweigh the reduced range but would I feel the same way if I couldn't charge for free at work and had to pay 70p/kWh instead? Probably not.

I'm getting less than 100 miles per charge, for our usage, with a trophy currently but I expected that having owned a leaf for 8 years. New owners won't realise this, and shouldn't really be expected to.

It doesn't help that people try to paint EV's in a too positive light by only focusing on summer savings, or long journeys etc. Or telling people they are driving it wrong. A 60-70% reduction in range is easily possible, as I am also seeing.

A newcomer to EV's might read things like "post your mi/kWh" threads (not necessarily on this forum) and think that it is representative of everybody when it's not. I've always tried to be conservative when posting about efficiency and think it would be better if we all did the same. It's not how far you can go in summer behind a lorry, but how far you can go at 70mph in the driving rain that really matters. Even that isn't perfect but would be a better baseline.

MoDolph said:

I'm getting less than 100 miles per charge, for our usage, with a trophy currently but I expected that having owned a leaf for 8 years. New owners won't realise this, and shouldn't really be expected to.

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100 miles range on a Trophy? Something is wrong or different, it should never be that low.

tsedge said:

100 miles range on a Trophy? Something is wrong or different, it should never be that low.

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It's easily possible. My routine currently is:

Wake up and defrost the car and drive 1 mile to nursery. Whilst there I keep the heating running whilst the Mrs takes the boy in then it's 1 mile to work.

Lunch is half mile trip home and back to work.

After work it's another preheat followed by a 2 mile drive to Asda before heading back to nursery. Once out of the car I'll activate the preheating again so it stays warm for the boy when he gets in before heading home.

I think this shows the benefit of EV's but also recognise that it might not be seem that way by everyone.

MoDolph said:

It's easily possible. My routine currently is:

Wake up and defrost the car and drive 1 mile to nursery. Whilst there I keep the heating running whilst the Mrs takes the boy in then it's 1 mile to work.

Lunch is half mile trip home and back to work.

After work it's another preheat followed by a 2 mile drive to Asda before heading back to nursery. Once out of the car I'll activate the preheating again so it stays warm for the boy when he gets in before heading home.

I think this shows the benefit of EV's but also recognise that it might not be seen that way by everyone.

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Ah... well that's the 'different' then and I get what you mean: you have this choice available to you in the way that an ICE car would not. Thanks for explaining.

tsedge said:

Ah... well that's the 'different' then and I get what you mean: you have this choice available to you in the way that an ICE car would not. Thanks for explaining.

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Yeah, it just shows how complicated the question of "range" can be.

I'm certain I can get 200 miles if I wanted to on a single journey whatever the conditions, but that's different to day to day range.

MoDolph said:

Yeah, it just shows how complicated the question of "range" can be.

I'm certain I can get 200 miles if I wanted to on a single journey whatever the conditions, but that's different to day to day range.

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Exactly the points I tried to make. Michael will think you must work for MG too

Michael1982 said:

so???? thats just what i do.
Do we live in a world now where a person can only use 1? and anything else is harassment and disrespect?

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I once sent an email to a japanese business and tried to indicate suprise by ending a sentence with !!!

They took that as me being very upset.

So if i called you silly in these ways they are all different

Are you silly

Are you silly?

Are you silly??????!?!

Are you silly!

Are you silly!!!!!!!!!!!!!

Punctuation and context matters.

Or should i say it matters!!!!!!!!!!!!!!!!!

On the problem that I think Michael mentioned on his blast where he cant do more than 60….

I think in the manual it states the 150kw motor is constantly rated at around 70kw.

So its 150kw peak but can’t maintain it for long periods.

So its possible that heavy footed use can heat up the motor which then gets power limited to stop overheating.

Im pretty sure that Tesla also has a constant power limit.