Miles/ kWh - Winter

[N2STY]

Yes.

I think even at the 7kw guessed at here as the draw from the HVAC, that's not much to get the battery of this size worked up. I could be wrong.

Only way to find out is with a ODBII adaptor and software capable of reading the battery temp.

Like this?

 

[N2STY]

I think even at the 7kw guessed at here as the draw from the HVAC, that's not much to get the battery of this size worked up. I could be wrong.

Only way to find out is with a ODBII adaptor and software capable of reading the battery temp.

So decided to test this

 

[mitchellleighton]

 

[mitchellleighton]

View attachment 13754

124miles range with 70% SoC, this used to be around 200 miles range minimum. Really not liking the winter!

 

[Maciej]

Sorry we got a bit of track here. Heating battery without charging will give me better range yes or no?

I know heating cabin will be nice I do it already but it isn't the same as heating battery up.

 

[Lovemyev]

I’ve mentioned thus before, but my experience (until just now on the forum) was that battery pre conditioning was used to prepare the battery for rapid charging (which I have had on a couple of my cars). It could involve heating (mostly for me) or cooling the pack ahead of rapid charging.
That was the purpose.
I’m now reading that it is also used to make the pack more efficient during normal use - which is a completely new one on me.
It’s a bit like warming your engine up to help it run more efficiently.
Anyway I’m interested to find out more on how this works

I was of the same opinion myself @Cocijo TBH.
I believe I have seen a settings, to turn on the battery precondition in the head unit.
So why bother having a manual switch then.
Unless it automatically turns on the heater, when the pack drops below a certain minimum / negative degree in ambient temperature.
I know it has been cold ? last week ( -6 here ) but I would have expected it to be lower than that, before it kicked in automatically myself.
I see this as a bit of a “Chicken & Egg” situation.
If you are using the battery heater either manually or automatically, to improve the actual range in freezing ? conditions.
Then the energy do this has to come from somewhere.
Either from the stored energy in the pack itself or from your wall box if plugged in.
So, I am charging the pack over night using cheaper off peak energy, then using energy on an expensive daily rate to heat the pack ?.
I can’t see any advantage myself, unless you have tariff that suits this type of behaviour.

 

[Cocijo]

yes, good points. I’m also interested how the battery conditioner actually works.

To heat the pack does it have perhaps a dedicated resistance wire that wraps around the pack and heats up when activated? Cooling will obviously use the structure that is in place with coolant pump and radiator.
If you set a supercharger destination in my Tesla it will start battery conditioning when it gets within around 5 miles of the destination - but this is mainly to speed up charging as I understand it. It’s a useful piece of additional programming, though what it actually saves I’ve no idea. I suppose if you’re paying £1/kWh you don’t want to use that rate to heat up your pack?
This only works for DC rapids, I understood there’s no need or benefit in pre conditioning for slower charging.
I am open to learn otherwise, but I really don’t see any benefit in heating up your pack, solely for driving and improving efficiency - yes cold packs are not at their best, but unless very cold, just drive off.
I don’t think battery heaters were ever primarily designed for that, certainly in the UK.
With electricity rates hitting record levels that no one really anticipated it puts a completely different slant on using peak rates to pre heat your cabin (and battery maybe) when plugged in.
It seems illogical to plan charges around your cheap tariff window and then use highest rate to heat things up…

 

[DB Go Rex]

So decided to test this

Assuming that was sped up overtime, then it's pretty much as I thought, no difference.

If you use the actual battery heater function in the app what does that look like?

 

[DB Go Rex]

It seems illogical to plan charges around your cheap tariff window and then use highest rate to heat things up…

Not if you just want to maximize range a bit.

If you have a round trip of say 180 miles and your range is 180 without heating the battery and 185 with....

 

[DB Go Rex]

Yes it does. Do MG have any user guidelines? I understand that it’s not automated?

Probably not.
Other makes seem to handle this better automatically.

 

[N2STY]

Done a 5 min battery heater test as got to work bit early
Before
View attachment 13747
Start up
View attachment 13748
5 mins
View attachment 13749

If you use the actual battery heater function in the app what does that look like?

I did see post above it basically draws a constant 3 kW on a 40 minutes drive heated battery coolant to 30 and battery to 20

 

[N2STY]

To heat the pack does it have perhaps a dedicated resistance wire that wraps around the pack and heats up when activated? Cooling will obviously use the structure that is in place with coolant pump and radiator.

It heats the battery by heating the HV coolant through a 3kw water heater now as for cooling not convinced it uses the rad think there is a cooler run off ac to chill the water ? The rad water is for motor cooling as that coolant stays cold in this cold snap

 

[Cocijo]

It heats the battery by heating the HV coolant through a 3kw water heater now as for cooling not convinced it uses the rad think there is a cooler run off ac to chill the water ? The rad water is for motor cooling as that coolant stays cold in this cold snap

Interesting thanks. So there’s two separate liquid filled systems for battery and motor.

 

[N2STY]

Interesting thanks. So there’s two separate liquid filled systems for battery and motor.

And if you look under the bonnet there are 2 separate coolant reservoirs

 

[Cocijo]

View attachment 13779
And if you look under the bonnet there are 2 separate coolant reservoirs

Superb. Very informative.