Cold Start - Thoughts?

The clarity already has a liquid cooled pack so a water/water heat exhanger wouldn’t have added many parts. If the pack was air cooled as it was with most of Honda’s hybrid systems it would use cabin air (like it did in my 2005 Civic hybrid with NiMH pack or my 2013 Civic hybrid with LiIon pack). In that case some heat could be put to the battery by preconditioning the cabin.

https://www.sae.org/publications/technical-papers/content/2018-01-1184/

 

Oh hell looks like it can use heat from charger and low speed engine operation.
From the SAE Article above.
“A valve installed before the battery in the cooling circuit allows it to be bypassed when coolant temperature rises due the charger or low-speed engine operation, helping to preserve battery life. Conversely, this waste heat can be used to heat up the battery when it is cold.“

 

Thank you for linking to that paper. I was completely wrong to believe that the cooling water didn't circulate through the battery pack.

 

I think I am going to do a real life experiment. The graph below is the forecast temperature for my location. Wednesday morning is supposed to dip below the magic 22°F limit. I think I will park my Clarity outside Tuesday night and see what happens on Wednesday morning. I am torn; it is a terrible thing to do to a piece of machinery (and won't be pleasant for my human body either) but I may be in a position where I actually need to know whether I can depend on the vehicle. If someone else beats me to this trial, please share!

 

I live north of Chicago,and park the car in my detached garage,past 3 days I've preheated it with level 2 carger,car started ,but I've driven it in hybrid mode considering that at 3 40 am temp.was even -12, so far no issues, but I would like to know if there is any way to warm up the ICE.

 

There is a secret procedure (but don't ask me where the shift lever is).

 

Shift lever=shift buttons

 

Yah. Hey der. Where’s the bubbler? Got any lutefisk?

So those of us in WI and MN (and I suspect moving East) without garages have three questions to answer during the forthcoming deep freeze:

1. Will it really not start at the listed -22’F?
2. Can timing a recharge help that? Read: Is the trigger on battery temperature or ambient temperature?
3. Will the maintenance mode procedure force-start the vehicle at that temperature and, if so, will you be able to actually move?

Given the coolant that envelopes the battery, while we’ve been warned that the *operating* limit is -22’F, is there a potential problem with even a non-operating (storage) limit?

 

Forecast here (GTA Canada) is for -25 C low's this week, without windchill. So we aren't hitting the magic -30 C yet... hopefully not at all! Every time I shut off my Clarity, it says "Low Ambient Temperature Detected - Recommend plug-in connection" or something like that. When it is plugged into the charger, on very cold nights I can see the charging activity come on periodically for little low-draw blips, which is the battery warmer in use. On the HondaLink app, it shows "Warming Up" underneath "Fully Charged" in the Battery section, in fact it is on right now. Pressing the "I" for more info, it tells me: "Warming up Battery: Temperature is too cold for vehicle to operate. Please wait while vehicle is warmed." Though it has never actually failed to start, to date. Current outside temperature is -9 C (windchill is -17, even though that is irrelevant.)

I have never paid attention to see if the warmer has come on when the car is not plugged in, because it is plugged in all the time when I'm home. The trouble will occur when I'm NOT at home, therefore not charging, in very cold temps, which is a lot of the time due to my work.

 

If my campus (University of Minnesota Duluth) is not closed on Wednesday, I'm considering Uber-ing in to work. During the day, temps (without windchill) are expected to hit -27F and I have only an open parking lot for the car to sit all day.

This weekend, I was at a cabin and the car was parked overnight outdoors. Morning temp (reported by car) was -19F. Car started and as I was driving home, car reported outside temp at -25F. Worked alright, but the ICE stayed on for the entire 100 mile journey. Stayed on even after "warming up" on the drive. And even after outside temp warmed up to -7F. Interesting.

 

I guess that’s better than just stopping when it gets cold. Can we conclude that if it starts, it will keep running regardless of temperature change?

 

Be careful up north everyone... just checked and lakeville area is down to -35F

 

This will be "the test." This will be the first official cold snap like this, for darn near every single Clarity that has been set loose in the wild thusfar So again absolutely nobody knows the answers to these questions yet. Please let us know when you find out!

Do you feel lucky? Do ya?

Again...let us know.

I'm looking forward to the chatter here over the next few days. I'm genuinely curious. I'm not far enough north to be part of the test group...predicting maybe -15 here where I am in Indiana, and I have an insulated and attached garage that never dips below freezing...plus a heater in there I can turn on if I choose to.

So I'll just be eating popcorn and watching the show mostly, as I also have little reason to go out anywhere during such weather. To those of you who may be out in it, be careful and have fun!!

 

If I were you, I would make the same decision on Uber. Our temperature range on Wednesday is forecast to be -33F to -20F. I'm not sure I would trust a conventional car to start in those conditions, but the Clarity would definitely stay at home.

Next time you're cruising at very low temperatures, try turning off the cabin heat to see if that drops you back into EV. I am not suggesting leaving it off, as I did not buy the car as a place to be uncomfortable and I'm perfectly happy to burn a bit of gasoline to keep my body warm. But my experience is that if I manually set the fan speed to minimum that the engine will shut down within a short time. I think it has decided that pulling that much energy from the battery to heat the cabin just isn't the right thing to do. And it's right.

 

-15F? Pfffft.

What we here in Duluth call "warm country."

 

Rajiv will be wearing shorts when it gets up to -15!