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Discussion Starter #1
Part of an ongoing discussion with colleagues but the Chinese battery manufacturing web site talks a lot about battery cooling but nothing about heating (pre-conditioning for rapid charging etc).

Does anyone know for sure if the MG has any form of battery heating and if so what the kW rating is?

Thanks!
 

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Part of an ongoing discussion with colleagues but the Chinese battery manufacturing web site talks a lot about battery cooling but nothing about heating (pre-conditioning for rapid charging etc).

Does anyone know for sure if the MG has any form of battery heating and if so what the kW rating is?

Thanks!
No heating, presumably because the designers consider that the energy/ power necessary would be quite significant, in order to quickly raise the temperature of the non-trivial thermal mass of the battery by any useful amount...
 

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Zoe Devotee
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Apparently it has heating and cooling, but from what everyone can tell the heating is only to prevent the pack getting too cold and not to warm it actively to aide charging speed.
 

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Zoe Devotee
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From the FAQ on the MG Site

"
DOES THE MG ZS EV HAVE BATTERY WARMING/COOLING?
A. The MG ZS EV is equipped with liquid cooling to keep the battery to the optimised temperature for best performance and range. During charging, the battery will be set to warm to an optimal temperature, so that even on cold days the battery performance will be optimised. During operation, it is natural for an EV battery to warm up, the liquid cooling will effectively cool the battery to optimise performance.

"

So maybe its only got cooling.... but maybe not. Bit vague sorry.
 

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TeslaBjorn posted recently about charging speed and how it's relatively poor when the battery is quite cold, suggesting that the thermal management is mostly about keeping the battery from overheating rather than warming it to optimal temp for charging.
 

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it's relatively poor when the battery is quite cold,
Yes and that was in Thailand where winter daytime temperature is 30°C. I doubt that MG regionalised the car's thermal management for UK and Northan Europe (as Kia has done for eNiro in various markets) to provide battery heating in colder climates and cooling in warmer.
 

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...I doubt that MG regionalised the car's thermal management for UK and Northan Europe (as Kia has done for eNiro in various markets) ...
Dunno - the Thailand market cars don't have a heater for the passengers, just AC!

Being able to see the battery pack temperature would be nice, as would a % SOC gauge. We know the car can show these features as you can see the SOC % when charging, and CCS uses pack temperature as one parameter for deciding charge rate.

In have turned the HVAC off on a very very cold morning and the current draw was 0 amps - unless the battery warming happens outwith the HV battery ammeter, it wasn't warming the pack (unless it also turns off with HVAC....)
 

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It not just the MG ZS.
Tesla Bjorn said that almost every EV suffers from the condition known as “Cold Gate”.
I think he said the Audi e.tron is maybe the exception.
Tesla has a facility to preheat the HV battery prior to arriving at its next charging station.
This allows for a faster charging speed In cold conditions.
Remember, he is conducting his tests in Norway !.
 

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Discussion Starter #12
Carty - it's a discussion I am having with Bjorn as he was insisting that it had a battery heater and I argued that it was not mentioned anywhere and the video only says battery cooling. It looks as though the only battery heating it has is associated with the HVAC system - so when the passenger compartment is warming up with the PTC heater, it uses some of that to warm the battery. But when HVAC is off there is no battery heating.
They seem to be very concerned about battery cooling though.
 

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Carty - it's a discussion I am having with Bjorn as he was insisting that it had a battery heater and I argued that it was not mentioned anywhere and the video only says battery cooling. It looks as though the only battery heating it has is associated with the HVAC system - so when the passenger compartment is warming up with the PTC heater, it uses some of that to warm the battery. But when HVAC is off there is no battery heating.
They seem to be very concerned about battery cooling though.
I am not thinking about travelling to Norway ( or anywhere that cold ) in my car !.
My old bones don’t take kindly to them cold conditions LOL !.
I am retired now and will be charging from home about 95% of the time.
The word “Rapid” does not apply in a lot of cases anymore.
If I had to sit at a “Rapid” charger a little longer because the HV battery is cold, then that okay with me.
I totally understand for busy people covering a lot of miles and long trips, it can be very important to be able to pull a lot of juice quickly and be on there way fast.
Charging on my home wall box overnight works great for us.
But maybe the first time I used a “Rapid” and pulled around 45 kw’s this would feel extremely fast to me.
I do have a personal opinion that constantly hitting your battery with these massive charging rates, can’t help the longevity of the pack surely ?.
I think Bjorn mentioned in one of his recent videos, that Tesla was going to introduce a software update that would down grade ( throttle ) the rate that there cars could charge at after so many Rapid charging cycles, to conserve the life of the battery.
They don’t want to hit for a lot of battery replacement claims under warranty I guess.
 

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Zoe Devotee
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Personally I watch Bjorn as a worst scenario video for MG not typical use. Yes some folk have had some slow figures in the UK, but they seem to in the main doing short trips from not such low SOC to rapids and then complain when charging speed is around 40kW. When I rapid charge its usually after an almost full discharge at speed going somewhere, in those circumstances I'll be expecting faster than 40kW, I won't expect faster than 50kW because that's what the UK model is advertised as, if I get faster speeds I'll be most happy.

Most of my long trips are when the weather is better, i.e. not winter, going on holidays with family. If I get anywhere near 50kW it'll be faster than I got with Zoe (which typically was around 38 to 40 at best charger dependant) I'll be happy. That coupled with the bigger pack will make the bigger car more family friendly for me on long trips.
 
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But maybe the first time I used a “Rapid” and pulled around 45 kw’s this would feel extremely fast to me.
When I rapid charge its usually after an almost full discharge at speed going somewhere, in those circumstances I'll be expecting faster than 40kW
I wouldn't be too disappointed with these charge rates either. My experience however suggests that if I was to get up tomorrow with a fully charged battery and drive 100 miles at motorway speeds to arrive at a good quality 50kW rapid charger with 20 miles remaining on the GoM I would expect a charge speed of around 33 kW. We can make excuses or choose to be satisfied with that but it is not what was advertised and falls below my expectations.

Back on topic, it is true that many EVs don't have active battery heating but some of these do benefit from heat exchange from cabin or HVAC. Either MG are less able to heat the battery compared to rival marques, or they have more conservative BMS or both.
 

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I wouldn't be too disappointed with these charge rates either. My experience however suggests that if I was to get up tomorrow with a fully charged battery and drive 100 miles at motorway speeds to arrive at a good quality 50kW rapid charger with 20 miles remaining on the GoM I would expect a charge speed of around 33 kW. We can make excuses or choose to be satisfied with that but it is not what was advertised and falls below my expectations.
This has definitely been my experience as I described the other day. When I had to wait half an hour to get on the charger I ended up with slightly higher charge rates which suggests more of an issue with cooling the battery rather than warming it. The issue of slower than promised charge rates, apparently more related to hot than cold, is more of an issue than whether the vehicle has active heating for the battery. No point comparing it to what a Tesla or an I-Pace has because it is neither and we haven't paid anywhere near what those sort of vehicles cost. for £25k there are going to be massive compromises to be had but, in terms of of bang for buck, it is the best EV on the market today
 

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When I had to wait half an hour to get on the charger I ended up with slightly higher charge rates which suggests more of an issue with cooling the battery rather than warming it.
Lots of factors can affect the charge speed you receive. I doubt if any UK car has got too hot for optimum charge speed just yet, though that may change if attempting long, fast trips in summer months. Any small variation you have observed may be due to the weather, the charger or local infrastructure (assuming similar SoC and battery temperature of car).
 

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Lots of factors can affect the charge speed you receive. I doubt if any UK car has got too hot for optimum charge speed just yet, though that may change if attempting long, fast trips in summer months. Any small variation you have observed may be due to the weather, the charger or local infrastructure (assuming similar SoC and battery temperature of car).
More than happy to put it down to crappy UK infrastructure to be honest. My brother owns an expanding network of chargers so I will test one of his this weekend and report back. Stupid questions but what is the calculation using the voltage and Amps to derive Kwh?
 
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