[Brian Matthews]

On a full charge, If I go a long distance on battery power and then recharge, my next expected range is usually around 44 miles but if I do 2 or 3 miles and then recharge, the expected range is higher. Yesterday I did 3 miles, then recharged and today I had an expected range of 48 miles. Has anyone else noticed this? Any theories why this happens, thanks.
Today I did 49.6 miles using 10Kw and the battery still had 4 miles left.

 

[Paul_Moxhay]

Can't say I undersstand it fully (no one does!!!) but as you know, that is just an estimate. It calculates the estimate based on how the car has been driven in the recent past. It is thought that it is the past 100 miles or so. So, all I can imagine is that when you drive a short distance it is normally at a slower speed than if you drive a further distance thereby lowering the average power used over the recent past and increasing the estimate.

As I say... I really don't have any firm idea but I think it is possibly something to do with that.

 

[Mike From Manchester]

I have to agree, it appears to be that the way the car is driven impacts on the future anticipated mileage. My better half has repeatedly pointed out that a full charge after she has depleted the battery always gives a better electric mileage forecast than when I have been 'allowed' to drive.

 

[Knightstonethornbird]

My Ampera has recently only been giving me 31 miles on a recharge, no matter how it's been driven previously or by whom. It seems to be dropping gradually.
The only unusual thing I do is quite a lot of long distances (300miles) and I wonder if it's affecting something. My car has done over 7000 miles, and I just hope the batteries are not deteriorating.
Anyone else have any thoughts?

 

[Paul_Moxhay]

I think that this kind of range is what we are all seeing at this time of year... I am only getting 30-35 where as I was getting 40-45 regularly in the summer.

Having said that I will be happy when I see it rise again in the spring and only then will we know if the batteries are deteriorating... I suspect they will be fine

 

[Big Paul]

I also believe it's "to be expected" as the ambient temperature drops. My forecast (and actual) range has dropped to very low 30's.

I sat in the car for about 40 minutes the other day with the "power" on just for heating and watched the range drop by 4 miles without going anywhere! I guess the same would have happened in a "regular" car but we just can't see such an effect without all the info displays!

Is it too early to say "Roll-on Summer"?

Big Paul

 

[proddick]

lots of discussion on US forum regarding cold weather range

http://gm-volt.com/forum/showthread.php ... g-about-it

If heading on a longer journey and will use all the battery, the idea of starting off in hold to get ICE heating certainly makes sense IMHO.

 

[dpeilow]

^ yep, I do that (did it again tonight).

 

[proddick]

Almost got 40 miles today - missed it by 0.3

 

[Paul_Moxhay]

Got 36 miles today... estimate was 29 miles !!!

 

[Duncan]

The estimate this morning was down to 34 miles, and I had to divert because of flooding so my route into work was 18 miles instead of the usual 14. I now have 14 miles estimated remaining and 18 miles again to get home so expect to be burning petrol before I get there.

 

[Paul_Moxhay]

Sounds like you need to get charging at work

I know that might not be possible in your particular case but some people are managing it (dpeilow for example) so it might be worth a try for some.

 

[Duncan]

I'm told there may be plans, but the main car park at work is already overflowing and they have to solve that first (possibly by installing barriers). Also I work for a charity, so there may be concerns about who pays for the electricity. One of my colleagues says he decided against buying an ev because of the lack of charging facilities (and he lives further away so he would need them every day).

Also, I didn't bring my cable today as I didn't think I would need it.

 

[Paul_Moxhay]

I feel for everyone who are having to try to resolve these kinds of issues... it isn't as simple as it might seem, I know.

 

[dpeilow]

Most big companies have environmental and travel policies that can be used to support getting charging. I just wrapped them up in their own argument.

 

[Duncan]

This morning the estimated range was down to 31 miles, but (unusually) I wasn't car sharing so I turned the heater off (except the automated seat heater). Round trip to and from work was 24.1 miles, 6.7kWh with 12 miles estimate remaining. Morning temperatures were -3C to -1C and afternoon was 3-4C.

If I count it right, scaling up the power used by the miles remaining only gives me 10.0kWh total which seems lower than I'd have expected, I'll have to check how much I actually get next time I use the full charge. Or it may just be that the estimate still has some component of max heat miles included in it.

 

[Parax]

I find it odd that the car still reports it has used 10.4kWh over just 28 miles. it feels like it is the motor being inefficient not the battery. As the cold affects the power released by the battery I'd have expected the power used to drop off also like the range.

I Also expected that the battery would be warmed more to extend range, does anyone know what the actual figures are for the battery heating?

 

[Duncan]

I find it odd that the car still reports it has used 10.4kWh over just 28 miles. it feels like it is the motor being inefficient not the battery. As the cold affects the power released by the battery I'd have expected the power used to drop off also like the range.?

I think the battery temperature management means the battery is still at the same temperature as it was in the summer, all that has changed is that it's now using a lot of that energy to heat the battery and the cabin. So output power should be the same but the motor gets less of it.

 

[Parax]

I think the battery temperature management means the battery is still at the same temperature as it was in the summer, all that has changed is that it's now using a lot of that energy to heat the battery and the cabin. So output power should be the same but the motor gets less of it.

That's an interesting idea, but if that were the case, I'd expect that using petrol preheat (below 0C) would give better range? as would one single drive using all the power rather than 3 seperate drives (allowing cooldown). Its all a bit puzzleing sometimes I wish the car would give you more details of what its doing..

 

[dpeilow]

It does.