EV mode warm up

I still don't think the car is actually using more energy. I've watched temperature gauges on hybrid assistant, and nothing warms up particularly fast in EV mode. I expect the battery current would be about the same no matter what temperature if the HVAC is off. I think it's just getting the indicated SOC caught up to the actual battery level.

How cold is cold? It's been 90 degrees in the day and 60 at night here. I wouldn't consider 60 to be very cold, but I guess relative to 90 it's colder.

I'm also convinced that how "fresh" the charge is makes a difference. For example if you let it sit without charging for a few days, the SOC will drop faster once you start driving than if you charged it the same day or the day before. But I haven't been able to test it to be sure.

 

I was thinking the same thing. We'd need to know what's meant by a "cold" car. Does that mean the engine hasn't been run or that you can see your breath inside the cabin?

The battery does have heaters, but I don't know the temperature threshold for turning them on.

 

I haven't done the experiment myself. So this is only speculation but I think a drop in SoC is more the function of multiple factors. The temperature may be a factor, but that is not the only one. In order to compare the "hot" vs "cold" in your description. I think you have to do the "Hot car" in exactly the same driving condition as your "Cold car". So, in your example, for "Hot car", you need to drive the car for a while until you get the SoC down to 6% and park your car in your driveway. Then, start immediately again and drive 1 km and record the drop in SoC. Compare this drop in SoC value to "Cold car" by doing the same but parking the car for a few hours before driving the same 1km trip. Of course even with this setup, if the ambient temp changes or way you drive the 1 km is slightly different say due to traffic, then there will be other variables playing in. But do this several times, and if "Cold car" always use more SoC on the same 1km drive, then your theory is more or less proven.

 

My understanding is that the heaters only run while charging. They come on when the battery is somewhere around 32-34 degrees and turn off once the battery reaches around 37 degrees F. I don't think they ever come on while driving. If the battery falls below freezing it becomes very hard to stay in EV mode.

 

aren't canadian primes different in regards to battery heating?

 

They just run the heater longer in Canada and Alaska, up to 30 days instead of up to 3 days, while plugged in. It's irrelevant for this discussion since ambient temperature is well above freezing. I only brought up heaters because jerrymildred mentioned them.

 

The hybrid assistant app can show you instantaneous power. It updates frequently in real-time (at least with my Bluetooth OBD dongle).

I watch the power consumption regularly, and I don't think you'll see any unusual consumption. If the car has been sitting for a while it charges the 12V battery, so "idle" power will be around 0.5-0.6 kW. If it is "warm" the "idle" power goes down to about 0.2-0.3 kW. But 0.3kW extra is not enough to explain a much bigger drop in SOC on a short drive. You could turn on the rear defroster and/or some seat heaters to cause an extra 0.3 kW load when the car is warm, and I don't think you'll notice much SOC drop a from that on a short drive.

In addition, if there was some additional consumption, you should see the same effect at both high and low SOC when the car is cold. The fact that it only happens at low SOC means it is probably something to do with the battery itself.

I still think the extra energy isn't being consumed or lost anywhere. The SOC is just being updated as the car "learns" the actual condition of the battery as you start driving.

I'm not saying the battery is discharging itself over time. The discharge while parked would be extremely low, probably too low to measure unless you leave it parked for two weeks.

But we know the range depends on battery temperature. In the summer you can get more range then in the winter, even if you could equalize all other variables. Here in Colorado we often have wife temperature swings in the winter, so that's as close to equalizing all variables as it gets.

So when you see the car lose SOC faster than expected, it is probably just noticing that the battery voltage (or some other parameter we can't see, that it uses to calculate SOC) has changed while it was parked, and it updates the display to catch up. I'm not sure why it can't do that while parked when you first start it, but I suspect it's not possible to really accurately measure the SOC of the battery until it's under some load.

 

I stand corrected!! I went back to John Kelly's deep dive and he states at least twice that the heater only comes on while charging and if the battery is under about 2C. So it would not be a factor here anyway since it's not that cold and it's not on while driving.

 

LOL

 

Oops. Should be "wide"

 

You have to be more gentle with the accelerator (made easier by ECO mode). Mine shows all kinds of values in between near zero when hard accelerating uphill and full when coasting. On level ground moving around 45 mph I usually see it hovering around 10 mi/kWh (6.2 kWh/100 km).

 

Hello,

I can confirm the same results with "cold car + low SOC " on my car ( 2017 Advanced ).

I'm always using GOM on miles ( km ) left and not percentage. I tend to believe that this has something to do with battery aging. I have 43000 miles on my car and I still can get around 38.4 miles with a full charge until ICE kicks in ( no A/C ). However, I've remarked the fact that with the same driving style, immediately after fully charging battery I can drive( let's say ) 4 miles with GOM decreasing only for 2 miles while the opposite happens when the battery is almost empty ( 4 miles GOM decrease while only 2 miles are driven ).
Overall I'm happy as I can constantly go above 32 miles with a full charge.

 

Are you finding this when the car is cold and comparing it when it's warmed up? OP's finding is not so much about full vs near empty, but warmed up vs cold start.

 

Immediately after charging battery, the temperature of the battery is quite high due to charging ... So I would not say my car is cold even if the car was not driven during last ( let's say ) 3 hours.
But if I will drive from a fully charged battery until ICE will kick in , then I will see those results...

 

To repeat OP's finding, you have to drive your car down to near empty 6% SoC remaining. And park your car at your home (or somewhere you can park your car over night. Drive the car right away or 12 hours (over night) later. Compare the distance you can drive from the same 6% SoC, when the battery is warm vs cold. Full battery is not a part of this experiment.

 

Do you have an ODB dongle to measure the battery temperature? It varies less than you might think. For example charging only increases it a few degrees, unless you're charging in direct sunlight. And the battery hardly cools off in 3 hours. It usually takes overnight to get significant cooling. In the summer my battery is usually around 95 degrees F if I've been driving or charging, and it usually stays at least 10 degrees above ambient overnight whether I charge or not.