Miles/ kWh - Winter

[Ruislip Resident]

I managed 3.8 average yesterday at -1C over 200 miles. How - by pre- heating the battery. I got it up to a toasty 20C before departing and initially managed around 3.7 m/kwh travelling around 60mph. This slowly dropped as the battery cooled so after 120 miles I topped up the battery and left with the battery temp at 26C. This then gave me 4.1 m/kwh until the battery started cooling. So the secret is to leave with a hot battery. Most of the time it was just seat heater with the HVAC off.

Do you heat up the battery with the charger plugged in. If so does the power to heat the battery come from the charger cable either whilst charging or not charging. I cant seem to find the answer to this. Or do you just heat the battery without the charger cable plugged in.

 

[Dragonfly]

You can do either, with or without the cable.

However if you're heating the battery, I would suggest you are doing a longer run, and not just popping to the local shop. So I would be looking to heat both the car and the battery with the cable plugged in. My take on this, is that the heating is done from the HV battery, but it also charges the battery at the same time. That is what makes the most sense to me, but I may be wrong.

 

[rpannell]

Do you heat up the battery with the charger plugged in. If so does the power to heat the battery come from the charger cable either whilst charging or not charging. I cant seem to find the answer to this. Or do you just heat the battery without the charger cable plugged in.

I cannot find a way to preheat with the lead plugged in. I had to remove the type 2, turn on the car, battery heat for about 40 mins, turn off car, pug in type 2 and recharge the battery to 100%. All a bit of a faff but as I was intending to do 200 miles without a charge, I needed the range. As mentioned, I did top up the charge part way but mainly to re-heat the battery.

 

[Ruislip Resident]

I cannot find a way to preheat with the lead plugged in. I had to remove the type 2, turn on the car, battery heat for about 40 mins, turn off car, pug in type 2 and recharge the battery to 100%. All a bit of a faff but as I was intending to do 200 miles without a charge, I needed the range. As mentioned, I did top up the charge part way but mainly to re-heat the battery.

How long does it take to charge back up to 100% after heating for 40 minutes, with starting the heating of 40 minutes whilst at 100%.

 

[rpannell]

It lost 4% battery capacity during the 40 mins battery heating so around 25-30 mins on a 7KW charger. The battery loses a couple of degrees during this time

 

[frb123]

I managed 3.8 average yesterday at -1C over 200 miles. How - by pre- heating the battery. I got it up to a toasty 20C before departing and initially managed around 3.7 m/kwh travelling around 60mph. This slowly dropped as the battery cooled so after 120 miles I topped up the battery and left with the battery temp at 26C. This then gave me 4.1 m/kwh until the battery started cooling. So the secret is to leave with a hot battery. Most of the time it was just seat heater with the HVAC off.

These are encouraging numbers compared to what others are reporting so gives me some hope!

EDIT
How are you specifically pre-heating the battery (only) before the journey? Is it just by having the car "ready" mode and having the battery heater toggle setting switched on? (And it does it's thing behind the scenes)

Presumably the increased batt temp you mention when you stopped (26C) was following a fast charging break, is that correct?

 

[rpannell]

These are encouraging numbers compared to what others are reporting so gives me some hope!

EDIT
How are you specifically pre-heating the battery (only) before the journey? Is it just by having the car "ready" mode and having the battery heater toggle setting switched on? (And it does it's thing behind the scenes)

Presumably the increased batt temp you mention when you stopped (26C) was following a fast charging break, is that correct?

Yes and yes. But with an outside temp of -1, the battery does cool pretty fast once traveling along.

 

[Lovemyev]

Most of the time it was just seat heater with the HVAC off.

Preheating the cabin & the HV battery before setting off is the secret here of course.
Combined with NOT using the greedy cabin heater while travelling, is the trick to keeping your efficiency so high in these much colder weather conditions.
If you need to conserve your range and are travelling alone then using the heated seat is great, but if you are carrying other passengers etc then the cabin heater has to be used really.
A family member has very recently ( about two weeks ago ) collected a brand new Merc SUV EV.
A loverly EV to be fair, but he has been shocked at just how quickly the range is dropping in this recent colder weather.

 

[Cocijo]

This MG estimated range calculator is interesting to play with (scroll down). It halves the range on motorway compared to slow work. It doesn’t take into account cold either, it’s an MG4 but you get the gist ..

All-New MG4 EV | Fully Electric Hatchback

MG4 EV is an affordable electric hatchback packed with innovation, style and up to an impressive 323 miles of driving range. Learn more now.

www.mg.co.uk

 

[Maciej]

Is there any benefit in heating battery unplugged on longer journey say 30ish mile? I can preheat on the way to work but on the way back can't charge and preheat

 

[N2STY]

Is there any benefit in heating battery unplugged on longer journey say 30ish mile? I can preheat on the way to work but on the way back can't charge and preheat

I think so when it's cold it's lovely jumping in the car and driving off when work colleagues are spraying and scraping there windows and leaving there cars running even if it worked out a bit more I would still do it as it happens with pre heat set at 24 work well for me drop it down to your comfort level say 20 and the you definitely get that 1% back in fact these very cold mornings -8to-12 this week I have been running it 2 times when I get home I am no worse off

 

[Cocijo]

I think we are mixing up pre heating the cabin and pre heating the battery pack.

 

[N2STY]

I think we are mixing up pre heating the cabin and pre heating the battery pack.

But pre heating the cabin will heat the battery pack

 

[Cocijo]

But pre heating the cabin will heat the battery pack

Will it? Ok. Didn’t realize that. I thought it was a separate setting and circuit.

 

[N2STY]

Will it? Ok. Didn’t realize that. I thought it was a separate setting and circuit.

Drawing current from a battery will warm it up due to the internal resistance

 

[Cocijo]

Drawing current from a battery will warm it up due to the internal resistance

Sure. But it’s not battery heating is it? It’s pre conditioning the cabin. Battery heating is completely different.

 

[DB Go Rex]

Sure. But it’s not battery heating is it? It’s pre conditioning the cabin. Battery heating is completely different.

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.

 

[Cocijo]

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

 

[DB Go Rex]

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 think it's no secret that batteries don't like to be too cold or too warm to work at their best.

In these current cold temps, heating the battery up to a half decent operating temp makes some sense.

 

[Cocijo]

I think it's no secret that batteries don't like to be too cold or too warm to work at their best.

In these current cold temps, heating the battery up to a half decent operating temp makes some sense.

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