Snow

[nikwax]

We've had our first snow of the year here in Portland, and of course I had to drive the Spark around to see what it was like.


First off, the preheat function is brilliant in these conditions. Seats nice and warm of course, back window completely clear. A few inches of snow on the windshield, but as the windshield was warm the snow very easily slid off. Side windows just required a light dusting to clear off the snow. I was ready to drive in about a minute.


Traction was very good. If I goosed the accelerator too much from a standstill, the traction control kicked in, and I quickly learned to go very easy on starts up to about 5 mph. No sign of traction control or slipping once under way. This was even true on ice, remarkably. No problem with cornering, or starting up from the curb with accumulated snow. Some credit may be due to the BFG tires.


Only odd bit: a bunch of snow ended up in the charge port and charge bay, I had to clean it out a bit to get the door closed.



The Spark continues to impress.

 

[nikwax]

Also: battery conditioning. First time I've seen that show up on the energy consumption pie chart. Temperature was about 28 F.

 

[NorthernSpark]

Do your BFGs have any noticeable impact on range? Still on the stock Ecopias here in the Canadian winter believe it or not. Good thing it's been a dry winter so far, relatively speaking. Even in the rain, I've noticed the tires spinning quite a bit from a stop, and that's not even punching the throttle. I did take it out when it was a bit icy just on our local roads and wound up several feet past a stop sign once, and that's when I decided I needed to get some better all-season rubber, but I was still researching tire models and keeping my eyes peeled for a deal. Are you running 195s all around?

 

[nikwax]

I drove the Spark home from the dealer and was so appalled by the tires that they were gone by the end of the week, so I can't say what the range impact is of the BFGs. I made a choice to trade range for traction, as range isn't much of an issue for me. In the summer, my GOM showed 80-100 miles of range, which included a fair amount of highway driving and air conditioning. In the cold and rain with the climate control running, the GOM is showing 60 miles. That sounds in line with what other drivers see.



That said, I'm sure there is some range penalty here, perhaps 5%. If range is an issue and you want high quality all season tires, maybe look at the Michelin Premier A/S. I'm very happy with the BFGs.

And yes, 195 all around. Lots more choices in this configuration, and no reason not to.

 

[Nashco]

TLR - Plug your Spark EV into a Level 2 EVSE and pre-condition it while plugged in to get significantly improved efficiency and range.

I've been getting more in tune with the battery conditioning as I get more miles on my (2014) Spark EV. I should probably start a "sticky" thread with tips on improving range/efficiency for all sorts of conditions, but for now I'll just put this here. I did a comparison test to show how much more range/efficiency you can get in the cold by leaving your car plugged into when you're not driving it and by pre-heating the cabin. I did one drive cycle with a fully charged, but unplugged and chilled car, and another with a fully charged car that was pre-heated before it was unplugged.

In both cases, the outside temps were around 30°F, and there was snow and ice on the roads. In both cases, I had the HVAC turn to "auto" and 72°F set temperature, two passengers were present with seat heaters used, and lights were on to keep conditions consistent. My car is a 2014 (A123 battery) that I've had for 2 years and it has about 15,000 miles on it.

In the case of the fully charged, unplugged car, I drove about 25 miles over a two hour period around snowy roads before and after breakfast. This included pre-heating the car (while unplugged!) twice, once in the morning for about 15 minutes when the car was completely cold soaked and once again for about 10 minutes after eating breakfast and before driving home. I got about 2.2 mi/kWh, the worst efficiency I've ever got when I wasn't racing. This is also BY FAR the most battery conditioning energy I've ever seen in my use case (even in much colder conditions).

Using the displayed numbers, that means my car is measuring:
18.4 kWh usable
10.1 kWh used
2.2 kWh for driving and accessories
5.5 kWh climate setting
2.4 kWh battery conditioning

I then plugged the car in, letting it charge and cool for about 5 hours. I pre-heated the car for about 15 minutes before unplugging it and going for a drive. I drove about 10 miles, watched a 2 hour movie, then pre-heated the car for about 10 minutes. I then drove about 10 miles. So this is very similar behavior from me from the earlier trip, pre-heating the car about the same amount of time while not driving. This resulted in about 2.9 mi/kWh.

Using the displayed numbers, that means my car is measuring:
19.2 kWh usable
7.3 kWh used
3.1 kWh for driving and accessories
4.2 kWh climate setting
0 kWh battery conditioning

The major takeaway is that this data supports what is said here often and in the owner's manual as well. If it's very cold, keep your car plugged in when you're not using it! In the case of the "cold" car that is unplugged, battery conditioning used more energy than driving, and HVAC was double the amount used for driving. If you're driving very efficiently (slow, snowy roads in my case), then the driving energy is only about 20% of the actual battery energy used!!! This is obviously worst case scenario, with short drives and a chilled car that is heating up to very comfortable temperatures, but in this case of non-ideal conditions our 110 mile car becomes a 40 mile car. On the flip-side, if you use the same scenario of short drives and a chilled car that is heating up to very comfortable temperatures and the ONLY change you make is leaving the car plugged in and pre-conditioning it while plugged in when possible, you can cut your energy use from the battery drastically. That means our 110 mile car can be more like a 55 mile car even in cold temperatures IF you make this minor change. Of course, there are many other things you can do to improve driving and HVAC efficiency, that's another post for another day, this was only focusing on the effects specifically of charging and pre-conditioning when cold.

On a related note, this is where the Spark EV really shines compared to the competition. None of my other EVs have been able to maintain their efficiency as well as the Spark EV in extreme temperatures. The temperature management on the battery is a huge boost to usability in extreme temperatures! The catch is that you will only see this big gain if you keep the car plugged in and pre-condition the cabin.

Bryce

 

[NORTON]

Awesome post Bryce !

I looked at my display on my way home last night: 6% heat, 4% battery conditioning. 28°.
This was after charging at an L2 early in the day, then moving the car at lunch closer to work, so it sat without being plugged in for 4-5 hrs.
I'm no longer going to do it that way.
I'm now plugging in at work on L1 at 12A. I'll see tonight if I get any battery conditioning. The battery pack is insulated, so hopefully not.

I still have not answered the question: If you are plugged in (at home,L2) and set the 'Delayed Departure' time so that you don't actually start charging at all,
will Battery Conditioning still draw some power to keep the battery at a happy temp? (probably not)

I can answer this myself but I need to switch my home EVSE to L1 and use a 'Killawatt'.

If it does not draw any power for battery conditioning while on delayed departure, I could modify my departure time to allow some charging at home.
Only my SOC can be different when I arrive at home, so my 'start of charge time' is variable.

 

[nikwax]

another data point: I leave my car plugged at home in 100% of the time. The battery conditioning that I saw, and it was only once, took place not long after I departed.

I agree that the thermal management of the battery is another feature that sets the Spark apart from certain other EVs.

 

[NorthernSpark]

I drove the Spark home from the dealer and was so appalled by the tires that they were gone by the end of the week, so I can't say what the range impact is of the BFGs. I made a choice to trade range for traction, as range isn't much of an issue for me. In the summer, my GOM showed 80-100 miles of range, which included a fair amount of highway driving and air conditioning. In the cold and rain with the climate control running, the GOM is showing 60 miles. That sounds in line with what other drivers see.



That said, I'm sure there is some range penalty here, perhaps 5%. If range is an issue and you want high quality all season tires, maybe look at the Michelin Premier A/S. I'm very happy with the BFGs.

And yes, 195 all around. Lots more choices in this configuration, and no reason not to.

I did notice the tires didn't have the best grip fairly early on, even though I bought the car in the middle of summer, during the driest weather. I think I have just been in denial :lol: Well I suppose the other factor is that it's my first EV and on top of that it was from a used car dealer, so I just wanted to make sure everything was stable with it first before plunking down $800 for new rubber. 7 months on and so far, so good. Will likely go with Michelin Premier 195s based on the good things I`ve read about them, so looking forward to that.

Bryce, I would also like to thank you for your informative post. I have already been in the habit of preconditioning but have never really paid attention to the chart showing energy usage. It was really cold today (-15C) so I preconditioned the car for about 15 minutes and amazingly, in my 40km trip, no energy was put towards battery conditioning. I had figured that due to to the cold, it may still be in effect for some period of time, but that was not the case. I still only have a L1 charger, so my range may take a small hit due to preconditioning, but it's not a big issue as we only will do 40km a day on average.

 

[sTeeve]

Terrific info, Bryce! Well done!


-Bob K.

 

[NORTON]

Another reason to avoid driving patterns that show 'battery conditioning' on the display is, it theoretically means you started your trip with the battery NOT in the ideal temp range.
This theoretically means you are giving your battery a less than ideal life, correct?

Lately since I started plugging in as much as possible I have not seen battery conditioning usage !

I know there will be times when 'That's life', such as leaving the car unplugged at an airport for a week in the dead of winter. (Nothing's finer than the Tropics in the winter !!)
In those cases you could do a cabin precondition, or two, if you have the range, from the phone app, while still taxiing in.
I believe a 'cabin precondition' while unplugged will also use power for battery TMS, correct? I don't know...

 

[Nashco]

If you pre-condition the car while it is unplugged and it is extremely hot/cold, it will use battery energy to condition the battery. Since this is at very low power levels to condition the battery before driving at higher power levels, I suspect the amount of "damage" done to the battery in these case is negligible. If you jump into a completely cold car and drive it hard, of course that is harder on the battery, but even then I would suspect this is negligible unless you live somewhere that is cold a significant portion of the year. Once or twice a year is definitely not going to cause a problem. Even then, the point of the conditioning is that the amount of time with "bad" conditions for the battery is very short. In the case of our previous Nissan Leaf, without heating or cooling there was nothing to do to immediately improve the situation if you were driving in extreme temperatures...you just caused damage while using the car!

By far the more likely concern is reduced driving range caused by the battery conditioning reducing usable energy available. In any case, in extreme weather, if you can plug in, do plug in!

Bryce

 

[NORTON]

.... In any case, in extreme weather, if you can plug in, do plug in!....

Too True!!!

Although, another aspect of Li-ion batteries is the 'shelf life' is longer if not stored at 100% charge, especially in very hot conditions.
(Most consumer goods with Li-ion batteries come from the factory with 40-60% charge because of shelf life concerns.)

This is one reason I felt good about charging only at work once a day and leaving the car over night with a 30-60% charge.
My battery spent less of its life at 100% just sitting there.

But now with this gadawful winter weather here, those days are done. My +8000 miles of free driving streak has ended... I'm now charging half the time at home at night..

Come on Spring Time !!!