Electric Vehicles and US' current cold snap

[friendly_jacek]

Originally Posted By: Nebroch
...or you can improve insulation, AC behaviour and waste heat management to get the heat up. Traditional cars have plenty of waste heat to use for heating purposes, so it hasn't gained much attention until now.


Electric/hybrid cars should use heat pump and not waste electicity in electric heaters.

 

[Jarlaxle]

They generally do...but that problem is simply that at very cold temperatures, heat pumps just don't work that well.

 

[Cutehumor]

interesting point. i hate to have an electric vehicle with 50% charge at work with 0 degree temps, then find when you get off, battery is down to 20% and not enough to make it home. I guess you really have to plan when you use these vehicles in the cold winter.

 

[[email protected]]

I drive a hybrid and the battery does suffer from "performance anxiety" in the Michigan winters. But even so, without using any techniques to squeeze out every last mpg, Im still averaging 45mpg.

I have no problem whatsoever with the heat output of my hybrid in the cabin, I start out with the heat on the hottest temp and within 5-10 minutes, I turn it down to 70 degrees because the heat is so hot. It heats the cabin just like our 2010 Escape does or my 2002 Bravada.

 

[BMWTurboDzl]

Originally Posted By: [email protected]
I drive a hybrid and the battery does suffer from "performance anxiety" in the Michigan winters. But even so, without using any techniques to squeeze out every last mpg, Im still averaging 45mpg.

I have no problem whatsoever with the heat output of my hybrid in the cabin, I start out with the heat on the hottest temp and within 5-10 minutes, I turn it down to 70 degrees because the heat is so hot. It heats the cabin just like our 2010 Escape does or my 2002 Bravada.


That's good to hear. Very cold and very hot conditions are my only concern with regards to EV. My diesel has a ceramic aux heater which starts churning out heat within 2 mins. It's one of the nicest features of my car and I'd hate to loose that by going EV.

 

[supton]

Originally Posted By: Cutehumor
interesting point. i hate to have an electric vehicle with 50% charge at work with 0 degree temps, then find when you get off, battery is down to 20% and not enough to make it home. I guess you really have to plan when you use these vehicles in the cold winter.


Technically, you have to plan in an ICE too. Carry a blanket, ice scraper, dress appropriately, run good tires, etc. Leave a bit early, so as to have enough time, since you lose time to scraping ice, and if the roads aren't perfect, from having to drive slower. Or around accidents. Also, make sure you have enough gas to make it between gas stations, but that's almost the same thing (albeit with faster filling up). [Get out on the highway, and it can be a long walk between exits.]

 

[Shannow]

True,
however, my feeling from the answers in the thread are that hybrids at least have enough waste heat to make the battery issues a pretty much non-issue.

If you have to waste electricity to make heat to keep the battery alive, it seems that pure EVs aren't really a cold weather companion.

JMH...with the reduced performance of cold batteries, is the energy lost, i.e. if you run it "flat" with diminished cold performance, is that a pure inefficiency, or does the (some?) energy become available when the battery warms up again ?

 

[IndyIan]

Originally Posted By: Shannow

JMH...with the reduced performance of cold batteries, is the energy lost, i.e. if you run it "flat" with diminished cold performance, is that a pure inefficiency, or does the (some?) energy become available when the battery warms up again ?

My lithium ion drill battery has as low voltage switch that shuts it off to prevent over discharging. In the cold I do find the voltage will rebound enough to run again even without warming it up. I think the potential energy is mostly avaiable in a cold battery, but the voltage it will produce and maintain is much lower with any sort of heavy draw.
Heated battery blankets are made to warm up normal car batteries for cold starts.