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Apologies for running an identical thread from another forum but:

I've been trying to record my rapid charging speeds since getting my new car a week or 2 ago. I do about 24k miles a year in my car so it's relatively important to me that I can charge quickly. Since owning the car I never seem to break 26kW on the rapid chargers... Even after driving from fully charged down to 10% in a single run before trying to rapid charge...

I've tried IONITY, BT Polar, Electric Highway & Shell Recharge but it's always the same...

I know my old leaf suffered from "Rapidgate" and it looks like MG have done a really good job at keeping the battery cool on these cars, but have they done it at the detriment of charging in cold weather (Coldgate)? I'd love to know how many other people have been experiencing this to understand if it's me or if there is genuinely an issue with the rapid charging on my vehicle.

As a side note, I've taken my car into the dealer and they're being excellent with trying to get information from MG but I'm struggling to find anywhere that MG details how fast the car should charge? In some placed it mentions 20% to 80% in 40 minutes (which would require about 40kW rapid charging) and in others (such as the FAQ's) it says that empty to 80% should be 40 minutes on a standard 50kW charger..

I'm just very confused and what I thought would be a good budget car with a thermally managed battery (heat when cold and cooling when hot) is turning out to be much less so.

I don't really want to go with the Battery Heater option because I'm also hearing some horror stories about it significantly draining the battery and the UK notes from service centres advise against it, saying it's irreversable and could lower the value of the vehicle in the future...

Open to discussion and feedback here guys as if I can't break 30kW then it's likely this is not the car for me.
 

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MG EZS 2020
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heat when cold
Current MG (in the UK) AFAIK do not heat the battery in cold weather. This is the subject of the next MG update, which I think is currently being rolled out. There are some that have had the update, one said it cost £65, that shows you use about 10 to 20% range with it on. Nothing about faster charging though.

The EZS seemed to be a bit of a work in progress. This is not unusual as my first (2015) Zoe gave me the impression, with the number of visits to the dealer for major repair work, that I was Beta testing for Renault.

I don't really want to go with the Battery Heater option because I'm also hearing some horror stories about it significantly draining the battery

It doesn't need to be permanently on. You could wait until you're a few miles before the chargepoint and then turn it on. I think that would be sufficient.
 

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Battery temperature plays a big role in charge speed as does state of charge.

I have seen over 70kW over the summer when it was warm, but the fastest speeds I ever got was in my 2nd charge. Every time.

I’m booked in tomorrow for the heater update, but unsure at the moment if I’ll go ahead. My dealer did not mention warranty being affected, despite me specifically asking that question, just resale value.

I not convinced this update has been implemented very well.

Battery heating does currently occur, but I think it doesn’t cut in until well under -10°C. I don’t know if it does it if the car is not switched on, or if the car has to be switched on for it to work.

With the update, it’s only really supposed to be used for 15 mins or so before a rapid charge to warm the battery. So I don’t know why it isn’t a toggle that has a timer built in for say 15 minutes. Plus why does the automatic heating have to go? Surely that is just poor code writing?

I also don’t know if it stays on all the time, or you have to turn it on every time you start the car.

If it’s on all the time, then why can’t they implement that for all the other settings we use like sport, Kers, camera recognition, manual speed limit etc.

MG are doing a great job overall and listening to suggestions, but some is poorly implemented.

I would love to sit down with them and discuss things with somebody at MG.
 

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Mike makes a valid point theyhave a tech team in UK at head office for mg uk.
Why not have a panel that our mg eV drivers could say have a zoom chat once or twice a year. as they build the cars. We drive them all the time so probably have far more insight on tweeks and ways maybe to improve them.
That surely would be winwin to mg
Maybe tho owners club could approach them and sound them out on that
 

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I’m averaging about 22 kWh from rapid chargers at the moment.

I was averaging 42 maybe a month ago, looking at my records November 24th.

On the plus side it no longer throttles the last 20%, it stays at 22 kWh until 100%. Before it would drop to 15 then 5 at the end.

I use rapid charging almost exclusively, i only slow charge once a month for equalisation. I’m aware this will cause aggressive battery degradation.
 

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Current MG (in the UK) AFAIK do not heat the battery in cold weather.
Not sure that's totally right. The battery heating is designed to protect the pack at extremely low temps. So if we got a week of extreme minus temps the heater should stop the pack getting too cold. What it doesn't do is actively heat prior to a charge (akin to Tesla). In fact I don't think any other firms do this. MG have an update that you can request that will allow this, but apparently it kills the auto heating protection at extremely low temps.

I've tried IONITY, BT Polar, Electric Highway & Shell Recharge but it's always the same...
I agree it is always the same. What you need to do is check with other owners as not all owners have the same issue. Seems its not an issue that affects all, but as is usual the ones that are affected scream the loudest.
 
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i3 94AH
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Hi Claw...
Don't despair yet. Yesterday with outside temperature of 12 degrees I managed 3 separate rapid/ultra top-ups starting from between 25%-52% at a 35kW rate for all 3. That is a first for me as I couldn't get better than 25kW rate before but they were at 3 or 4 degrees. I was hoping for more on the ultra unit starting at 25% but happy to get an improvement. According to a graph I saw on Fastned the rate should be 76kW max around 17% tailing off to less than 50kW at 47% and maintaining 36kW to 80% then dropping to around 15kW/h rate. If I cannot improve on 35kW during the spring/summer then I will be getting my dealer to check the BMS. I know I haven't got the latest update as I can't fast charge with the doors unlocked but that is not an issue for me unless that update increases the rapid rates.

Open to discussion and feedback here guys as if I can't break 30kW then it's likely this is not the car for me.
[/QUOTE]
 

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This was my second rapid of the day in temperature of around 25°C

138557
 

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I’ve rapid charged approximately 90 times in the last three months, maybe 1700 kWh. It’s only the last month that rapid charging has halved in speed. Yesterday I charged 73 minutes, 25.4 kWh 34% to 100%.

Also wanted to comment that the hvb fuse update (charge while unlocked) has no effect on battery charging speed.

I’m suffering with Winter charging speed slowness and low range. I’m averaging 1700 miles a month and I’ve saved £500 in three months vs petrol/diesel so I’m pleased I went with mg eZS.
 

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I don't doubt that if you know what you are doing and start a second or third rapid of the day from a very low SoC it is possible to get high powered chargers to peak at good rates for a short period but posting pictures like this is a little disingenuous.

Will the average MG ZS EV driver achieve the claimed 0-80% charge in 40 mins this time of year? No they won't. They would do well to get from 20-65% in 40 mins (an average charge rate of less than 30kW).

In my experience charge rates are acceptable in warmer months, and I could live with a gradual tail off in performance as it gets cooler, but there does appear to be a cliff edge beyond which waiting for a rapid charger to deliver sufficient power to complete the next leg of a journey becomes painful.
 

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I don't doubt that if you know what you are doing and start a second or third rapid of the day from a very low SoC it is possible to get high powered chargers to peak at good rates for a short period but posting pictures like this is a little disingenuous.

Will the average MG ZS EV driver achieve the claimed 0-80% charge in 40 mins this time of year? No they won't. They would do well to get from 20-65% in 40 mins (an average charge rate of less than 30kW).

In my experience charge rates are acceptable in warmer months, and I could live with a gradual tail off in performance as it gets cooler, but there does appear to be a cliff edge beyond which waiting for a rapid charger to deliver sufficient power to complete the next leg of a journey becomes painful.

It has been confirmed that the battery warming software update replaces the automatic battery warming that occurs, albeit at very cold temperatures.

This has put me off having the update (not that we suffer very cold temperatures in the U.K.) and even though my car is garaged when not in use and therefore less likely to suffer cold damage.

My use of the software update does not seem to be for the common reason, that of enabling higher charge rates at rapids, It was instead because it would give me much better range if I preheated the battery prior to starting a journey (in the depths of winter), It should allow this whilst on charge which could have meant winter range almost on a par with summer use.

As an alternative to the software upgrade, I would be very interested to find out if there was any way to trigger battery warming on a one off basis ?
 

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It is difficult to comment because there insufficient info in the public domain, but there appear to be some pretty firm boundaries whereby if you commence a rapid charge at a battery below the temperature threshold or above the SoC threshold then the charge rate is dramatically reduced. The battery heating update appears to allow user to manually turn on the battery heater but without understanding what these threshold values are, how much energy is used and how long it takes to heat up the battery to the required temperature to enable more rapid charging, I'm not sure how useful it is.

In my view battery condition would be better managed if charge rate tapered more gradually, or battery heater and liquid cooling worked more dynamically to keep the battery temperature in the goldilocks zone, or manual heating acted as an override that could be switched on before rapid charging. The software should in any case protect against extremes of heat and cold but extra heat could be diverted to the battery for a short period on flicking the now redundant battery switch. Once battery had reached the necessary temperature the extra heating should turn off automatically and not require the driver to do it manually.

I wouldn't take the battery heater update at the moment because I'd be afraid that I'd not remember to turn it on or understand when to turn it off again.
 
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