Road tripping in the MG4

[Werrex]

The 77kWh battery pack is NMC ... the only battery pack in an MG4 that is LFP is the 51kWh one.

Thanks for the correction.

Still, wondering if anyone else has come across similar behaviour or abnormal charging curves on their MG4s. Quick search around the forum didn't result too many graphs at least.

 

[mg4]

I have a similar observation to yours on the charge curve. It is nowhere near that praised flat charge curve i read everywhere about. You can see the gif i posted and it has a frame every percent change, so it is easy to chart it out.

It starts high for me, 130-134, then dips to about 80 above 20% and over 5% it returns to 130 or so. But i just gave up on watching it. It is what it is for me, only if you want precise to the minute charge times, you will be dissapointed

 

[Werrex]

I have a similar observation to yours on the charge curve. It is nowhere near that praised flat charge curve i read everywhere about. You can see the gif i posted and it has a frame every percent change, so it is easy to chart it out.

It starts high for me, 130-134, then dips to about 80 above 20% and over 5% it returns to 130 or so. But i just gave up on watching it. It is what it is for me, only if you want precise to the minute charge times, you will be dissapointed

That's a bummer, considering that early high power throughput is what really counts when driving long distances with several charging stops each day.

Has there been any explanation whatsoever from dealers regarding this unusual charging curve?

 

[dave99]

interesting thread! Whats peoples thoughts about not having a spare tyre when touring in Europe? I'm thinking about driving down to spain next year and an earlier comment about the lack of a spare rung a concerning bell in my mind I assume MG Assist with the AA only covers the UK (or country of purchase)

 

[mg4]

interesting thread! Whats peoples thoughts about not having a spare tyre when touring in Europe? I'm thinking about driving down to spain next year and an earlier comment about the lack of a spare rung a concerning bell in my mind I assume MG Assist with the AA only covers the UK (or country of purchase)

I went through the horrible roads on the Balkan 3 times and never had a flat, actually, never in my life (yet) so i don't carry one.

 

[wattmatters]

Still, wondering if anyone else has come across similar behaviour or abnormal charging curves on their MG4s. Quick search around the forum didn't result too many graphs at least.

It's not the easiest thing to gather data on unless you can be bothered to set up an OBD reader with a device to capture the data which is left in the car. Most people would use their phones but I'm not sitting in the car while it's charging, I'm off doing something else.

I did a rough curve based on a Supercharger session a long time back in my 64 kWh MG4:

Note that the car itself is not the only factor determining charge rate. Charge stations also adjust how much power they deliver based on various factors.

 

[Jamesrr]

Thanks for the correction.

Still, wondering if anyone else has come across similar behaviour or abnormal charging curves on their MG4s. Quick search around the forum didn't result too many graphs at least.

I too have a Trophy ER / Essence LR 77 (which is indeed an NMC battery).

I don't think your graphs look that "unusual" to me. I regularly see the 144kW max rate at 20% SoC which by the time I'm back at the car at 80% SoC has dropped to 40ishkW. Obviously, after that the rate starts to drop significantly.

I've never been bothered to try and get an exact "plotted curve" because I've got better things to do, like visit the bathroom or grab a bite to eat By the time I'm back from that, the car is ready to go. My typical charge session gets me an overall average 90ish kW rate which is more than ample to do long distance trips.

I've done the 1,500km 2 day journey from our place in Sydney NSW to our holiday house in country South Australia 3 times with the 4th coming up in another 3 and a half weeks. I break the trip over 2 days doing 720km the first day with 2 half hour DC charging sessions, overnight AC recharge at the motel, then 780km the next day with 3 shorter DC charging sessions of around 1:10minutes total.

The car handles long trips really well.

Note that the car itself is not the only factor determining charge rate. Charge stations also adjust how much power they deliver based on various factors.

This is important to keep in mind. The Kempower units (which I'm always happy to see as the delivery unit!) are really good IMHO because they dynamically load balance their total power delivery capability amongst the plugs.

It's also worth keeping in mind that the power rating of the Kempower (and plenty of others) is based on 800V whereas the MG4 and many other EVs are only 400V. For example a 150kW Kempower unit may only deliver 100kW to a 400V car. If another car plugs in, it will then both load balance the total power based on the relative SOCs the now 2 cars are at.

In the big picture, I find I get very acceptable charge rates and under "good" conditions regularly get 10-80% charges in the advertised 38 minutes. Of course, more typically I'm only in need of a 50-60% SoC top-up and by the time I've had my pitstop I've already put in more than I "need".

Very good value for money long distance tourer.

 

[Werrex]

I too have a Trophy ER / Essence LR 77 (which is indeed an NMC battery).

I don't think your graphs look that "unusual" to me. I regularly see the 144kW max rate at 20% SoC which by the time I'm back at the car at 80% SoC has dropped to 40ishkW. Obviously, after that the rate starts to drop significantly.

I've never been bothered to try and get an exact "plotted curve" because I've got better things to do, like visit the bathroom or grab a bite to eat By the time I'm back from that, the car is ready to go. My typical charge session gets me an overall average 90ish kW rate which is more than ample to do long distance trips.

I've done the 1,500km 2 day journey from our place in Sydney NSW to our holiday house in country South Australia 3 times with the 4th coming up in another 3 and a half weeks. I break the trip over 2 days doing 720km the first day with 2 half hour DC charging sessions, overnight AC recharge at the motel, then 780km the next day with 3 shorter DC charging sessions of around 1:10minutes total.

The car handles long trips really well.

This is important to keep in mind. The Kempower units (which I'm always happy to see as the delivery unit!) are really good IMHO because they dynamically load balance their total power delivery capability amongst the plugs.

It's also worth keeping in mind that the power rating of the Kempower (and plenty of others) is based on 800V whereas the MG4 and many other EVs are only 400V. For example a 150kW Kempower unit may only deliver 100kW to a 400V car. If another car plugs in, it will then both load balance the total power based on the relative SOCs the now 2 cars are at.

In the big picture, I find I get very acceptable charge rates and under "good" conditions regularly get 10-80% charges in the advertised 38 minutes. Of course, more typically I'm only in need of a 50-60% SoC top-up and by the time I've had my pitstop I've already put in more than I "need".

Very good value for money long distance tourer.

Thank you for the comprehensive write-up and for sharing your experiences!

It does indeed vary between many things and load balancing could have also been a factor in those graphs of mine. Kempower chargers are indeed very handy as they provide you with a single-use QR code at the start of your session to a website that you can use to monitor the progress and charging speed while doing one's business elsewhere. After each session the site then updates with the given charge curve - would love to see more operators implement this or preferably Kempower chargers as they've never failed me so far at least (Looking at you ABB).

The reason why I'm curious, or rather worried, is that I too plan to do some roadtripping for the winter - from Finland to Portugal, in fact. And a whole day of driving with 2-3 charging stops sounds like a blessed relief to someone who has completed the same journey twice previously but in a Peugeot e208 with a 50kWh battery and much less range and lower charging speeds.

With that car a typical day required 5 charging stops per day plus the overnight charge or a top-up before arriving at thr hotel, especially on days with mainly highway driving.