Indications for using battery heating (now the weather is getting colder)

[Rolfe]

That's an improvement from the car suddenly telling you it's a bit chilly out and do you want to turn on battery heating, when it's 20 in the shade.

 

[smurfy1962]

Hi there . On the MG4 that i have it has a function for heating the battery. So when is it the best time to use this facility?

 

[AndyL61]

It reduces your range. Personally I wouldn't use it. It supposed to help to increase rapid charging speed by warming the battery but it actually uses quite a noticable amount of energy to do this.

 

[Rolfe]

I've merged this in with an earlier thread, so keep all the information and advice together. I think the earlier pages cover quite a lot of the issues.

 

[Anon70]

In this Winter tips video Burl Solomons suggests using battery heating on cold days before starting off on a journey to get better efficiency (and running the heating while still on charge)

 

[Brettus]

Preheating while on charge does depend if you need ALL the battery or not as quite often you’ve filled it with cheap kwhs overnight and are then paying 3x the price for heating kwhs to save you using the cheap ones you’ve stored.
Might seem obvious but just mentioning it as it’s usually news to someone.

I do the other extreme, fill the battery and use those cheaper kwhs to heat my office/lounge during the day to save using grid ones but that’s getting OT now.

 

[securespark]

What about "intelligent battery heating" that we were all urged to turn off in the spring to improve our miles/KWh figures? How intelligent is it? Should we just be leaving it on in winter, or not when we're only doing short journeys?

IDK how to turn this on or off...

 

[Rolfe]

There's a screen on the infotainment screen. Try the car icon, then charging?

 

[siteguru]

Battery tile, Energy Consumption tab ... the option is there.

 

[Alex1985]

How much power does the battery heater use.
Will it work whilst on the charger and does it enhance the miles per kw on a cold day.
Aproximately how long does it take if the overnight temp drops to 0 degrees to raise the battery temperature before before use.

 

[Rolfe]

I've just merged this in to keep all the battery heating info in the one place.

 

[fnegroni]

How much power does the battery heater use.
Will it work whilst on the charger and does it enhance the miles per kw on a cold day.
Aproximately how long does it take if the overnight temp drops to 0 degrees to raise the battery temperature before before use.

I think it’s a 7kW heater: whenever I’ve used it at sub zero temps it has run for 20 minutes and used 2kWh.

 

[lfc958]

With winter coming up I decided to start investigating battery preheating, there appears to be a lot of confusion, however the main thread I seem to be getting here and elsewhere is .

1. If outside temp is 10 C or less then use preheat battery from app before going out.
2. During cold weather (no one can say what is cold) utilise preheat from inside car heading to charge, the Burt Solomons video seems to recommend 10 mins before.
3. If you try to preheat battery from app before going out and the temp is not low enough I get an error message as mentioned above.

Looks like a little more 'investigating' is needed and a "dummies guide" pinning to this forum for all to read.

 

[hharzel]

For me the important question is, will it ruin the battery if it is never used under below freezing conditions and shorts trips. Because for whatever reason, the car is still regenerating as I leave my parking space, even if it is -8C outside - it should not regenerate at all due to lithium plating issue. The battery temperature is hidden, but I doubt it is above zero if the car has been standing outside for over 12 hours. As I deal with inferior software daily at my work I have some serious trust issues when it comes to software....

 

[lfc958]

For me the important question is, will it ruin the battery if it is never used under below freezing conditions and shorts trips. Because for whatever reason, the car is still regenerating as I leave my parking space, even if it is -8C outside - it should not regenerate at all due to lithium plating issue. The battery temperature is hidden, but I doubt it is above zero if the car has been standing outside for over 12 hours. As I deal with inferior software daily at my work I have some serious trust issues when it comes to software....

I understand your reticence over trusting software having worked in the industry for over 30 years.
This is why I believe that constant looking at what is being shown and comparing each data reading will eventually reveal a constant figure that can be taken as the baseline and close to the truth.

 

[fnegroni]

For me the important question is, will it ruin the battery if it is never used under below freezing conditions and shorts trips. Because for whatever reason, the car is still regenerating as I leave my parking space, even if it is -8C outside - it should not regenerate at all due to lithium plating issue. The battery temperature is hidden, but I doubt it is above zero if the car has been standing outside for over 12 hours. As I deal with inferior software daily at my work I have some serious trust issues when it comes to software....

The regen strength is controlled by the inverter
It could be that the rectifier then converts that energy into heat or simply reroutes it somewhere else. The preconditioning (battery heating) will be even more beneficial at this point.

 

[Rolfe]

Looks like a little more 'investigating' is needed and a "dummies guide" pinning to this forum for all to read.

This is a damn good idea! Are you volunteering?

 

[tsedge]

For me the important question is, will it ruin the battery if it is never used under below freezing conditions and shorts trips. Because for whatever reason, the car is still regenerating as I leave my parking space, even if it is -8C outside - it should not regenerate at all due to lithium plating issue. The battery temperature is hidden, but I doubt it is above zero if the car has been standing outside for over 12 hours. As I deal with inferior software daily at my work I have some serious trust issues when it comes to software....

No it won't ruin the battery - the car will limit charging speed (including via regen, which is a low level of charging anyway) to levels below the threshold of plating onset. This is pretty well understood territory these days: the battery heater will serve to enable higher charging speeds.

There's reams of evidence now that EVs survive well in cold countries.

 

[lfc958]

This is a damn good idea! Are you volunteering?

When I know what am talking about then I can

 

[mg4mc]

I think it’s a 7kW heater: whenever I’ve used it at sub zero temps it has run for 20 minutes and used 2kWh.

I see a 7kW draw on my charger when using the battery heater and plugged in with pre-conditioning active