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I'm pondering a longer distance drive come January and would love to find a graph of EUV range versus ambient temperature. Living in the frozen tundra Wisconsin wasteland, and it get cold in January.

Anybody with a suggest where to look? Any advice for cold weather range maximum techniques other than no heat, slower speed, pre-conditioning?
 

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Any advice for cold weather range maximum techniques other than no heat, slower speed, pre-conditioning?
What you need to remember are two things :
  • a warm battery is a better battery
  • you can only control the speed and the tires pressure out of the rest of things that influence the range of an EV

So, you make sure the battery is warm at the start of the trip by using delayed charging and set it to end a full charge an hour before you start your trip. In the hour left, you should do two pre-conditionings of the cabin. This way you have a crispy hot cabin and if the car needs a battery conditioning, it will do it.

I am against the "don't use heat", but instead of using "Auto" when the heater is on, use the fan speed 2. I use to drive with 20C set on heater on very cold days, and 21C usually in winter.

When you are at about 15 mins from the DCFC, crank up the heat to HI and make the cabin crispy hot. Do some "yo-yo" for 10 minutes. What "yo-yo" means ? To speed up and then brake hard, but do it safely (for exemple, if driving 65 mph, accelerate hard to 75-80 mph then brake hard to 50 mph). Then repeat. This way, the battery that wasn't too much solicited while driving at a steady speed, will be forced to "move the electrons between the packs" and warm up.
When you charge at a DCFC, don't use the heater for the first part of the charging session (about 50% SOC, when it starts to stepdown the speed). The electrons will all go to the battery and its conditioning instead of the heating the cabin. This is why I told you about the 15 mins Max heat.

For the rest... one last thing. Keep an eye on your average (mi/kWh). It will tell you the story. Reset the Average in the DIC before you start the trip. It will become accurate after about 20 miles in the trip. And the Min value of the GOM, compare it always to the distance to the DCFC. If the Min is above it, great. If it's showing a trending towards less than the destination, lower the speed.
 

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What you need to remember are two things :
  • a warm battery is a better battery
  • you can only control the speed and the tires pressure out of the rest of things that influence the range of an EV

So, you make sure the battery is warm at the start of the trip by using delayed charging and set it to end a full charge an hour before you start your trip. In the hour left, you should do two pre-conditionings of the cabin. This way you have a crispy hot cabin and if the car needs a battery conditioning, it will do it.

I am against the "don't use heat", but instead of using "Auto" when the heater is on, use the fan speed 2. I use to drive with 20C set on heater on very cold days, and 21C usually in winter.

When you are at about 15 mins from the DCFC, crank up the heat to HI and make the cabin crispy hot. Do some "yo-yo" for 10 minutes. What "yo-yo" means ? To speed up and then brake hard, but do it safely (for exemple, if driving 65 mph, accelerate hard to 75-80 mph then brake hard to 50 mph). Then repeat. This way, the battery that wasn't too much solicited while driving at a steady speed, will be forced to "move the electrons between the packs" and warm up.
When you charge at a DCFC, don't use the heater for the first part of the charging session (about 50% SOC, when it starts to stepdown the speed). The electrons will all go to the battery and its conditioning instead of the heating the cabin. This is why I told you about the 15 mins Max heat.

For the rest... one last thing. Keep an eye on your average (mi/kWh). It will tell you the story. Reset the Average in the DIC before you start the trip. It will become accurate after about 20 miles in the trip. And the Min value of the GOM, compare it always to the distance to the DCFC. If the Min is above it, great. If it's showing a trending towards less than the destination, lower the speed.
May I ask why you set the delayed charging to end an hour before you leave? Wouldn't the car just use grid power to do the preheats while the battery is still charging up until you leave? Just checking to make sure that you don't lose any SOC in the hour before you actually leave. Thanks!
 

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May I ask why you set the delayed charging to end an hour before you leave? Wouldn't the car just use grid power to do the preheats while the battery is still charging up until you leave? Just checking to make sure that you don't lose any SOC in the hour before you actually leave. Thanks!
Let’s say you drive 100 miles a day, and you use 35 kWh of the battery. You arrive home @ 6 p.m. and you plug the car in. Your EVSE gives you 7.2 kW/h so your car will be fully charged in 6 hours (including the loses on the circuit). So, you have a fully charged battery at midnight. Until the next morning, your car will sit doing nothing (charging wise) for 7 hours. If outside is cold/very cold, and given the fact that the conditioning of the battery is triggered at a lower battery temperature while it doesn't charge versus when it charges, you have a colder battery in the morning in this situation vs setting the delayed charge for 7 a.m. next day. That’s all it is.

And no, you don’t lose any energy while the car plugged in, is sitting or is doing the pre-conditioning unless the EVSE can’t supply the power needed by the pre-conditioning. The pre-conditioning takes 20 mins once, you do two, that’s 40 mins. When you wake up, you might want to do your stuff, then remember to start the pre-conditioning. That’s why the other 20 mins were added to make up for the hour I mentioned.
 

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Discussion Starter · #6 ·
Thanks to all for your inputs. I'll have to factor in the upcoming January conditions that day when the time comes. I'm a bit surprised to see the sharp linear downward slope with temperature drop, but I understand. Electrochemistry likes moderate ambient temperatures, and sure slows down in the cold. I do too.
And so it goes.
 

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One thing that most people overlook during the colder weather is tire pressure. I'm losing between 3-6 PSI per tire whenever the temperature drops a good 5-10 degrees (that's F for you weirdos that use that fancy pants "metric" system 😝 ). I think since the cold weather has hit earlier last month, I've had to air up my tires at least 3 times already to keep it at the same PSI. I'm tempted to go to the dealership that sold me the car and tell them that since they insisted I pay $700 for nitrogen, that they need to refill my tires with the "right amount" of what they charged me.
 
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