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Winter & Cold Weather EV Range Loss in 7,000 Cars

recurrentauto.com

201–210 of 332 posts

Re: Winter & Cold Weather EV Range Loss in 7,000 Cars

#201
post #50

My fuel economy drops about 20% on my petrol car in cold weather city driving. I don't know what causes the difference, perhaps waiting for the car to warm up and windows to defrost.

Warming up the whole car (including grease in wheel hub bearings, for example, that becomes much harder in cold) takes a lot of energy, so perhaps it is it. I'd say that a fully warmed car though should be a bit more efficient due to a bigger temperature difference and a bigger oxygen amount going into cylinders.

People drive differently in really cold weather - they tend to idle the vehicle more (and spend time in it while idling more), drive slower, and on mushier surfaces (snow/slush/ice), etc. and that is without figuring mechanical stuff like thicker oil.

If someone isn’t driving highway distances all the time, ‘warm up’ is quite inefficient for ICE vehicles, and tends to run very rich.

Totally right that if those factors aren’t there, it should get better fuel economy.

Re: Winter & Cold Weather EV Range Loss in 7,000 Cars

#202

Forget driving range... how do EVs cope with long term parking, and how much does the winter affect that? I have become acutely aware that some car designers have not really considered "must work after parking" as a feature of a car. I had not thought much about it, but some ICE or HEV cars cannot maintain their basic (non-traction) battery unless driven several times per week at minimum. I had not thought about this…

They definitely handle it a lot better than ICE cars!

ICE cars, more than a week or two with any frequency is tempting fate.

Re: Winter & Cold Weather EV Range Loss in 7,000 Cars

#203

Earlier quoted context omitted.

It's called a block heater and they have been in use for many decades in cold climates.

Block heaters don't heat the cab, so it's still uncomfortable

I wasn't claiming that they did. The block heater keeps the engine warm to allow for easy remote start.

Re: Winter & Cold Weather EV Range Loss in 7,000 Cars

#204
post #80

Yes northerner checking in here. Yes in the winter at sub zero temps your cars battery looses half of its starting crank amps. Half just from the low temps. Makes complete sense that an EV would have much worse performance in winter conditions. Further longevity of such vehicle would likely be much less than one found it warmer temps. We still have a ways to go to solve EV issues for mass adoption… however am optimis…

As with all things ‘it depends’ - most EV’s have battery thermal management that will heat up/cool down the pack so it’s within its optimal range.

If the EV is left plugged in overnight, it’s probably going to be in better shape than an ICE car with a block and battery heater.

Re: Winter & Cold Weather EV Range Loss in 7,000 Cars

#205

I can’t decide on my next car - Live in cold village on US east coast - ICE might be going obsolete - BEVs are improving quickly so what I buy might be superseded soon - feels almost like the early days of smartphones. - Gas prices are very high - Used and new car prices are unreasonably high - There’s not enough chargers to support the number of EVs being driven in my area leading to long waits. - I could charge at…

The ICE will not be "going obsolete." There's no real replacement and there won't be just because of the underlying physics. There are too may drawbacks with EVs that they'll never be for everyone and everywhere. If your 150k mile car is a reliable brand (i.e., Honda or Toyota), you probably have another 150k miles on it.

They are already obsolete for most usages in Norway.

Re: Winter & Cold Weather EV Range Loss in 7,000 Cars

#206

I find it strange that the charts only go down to 20°F, when for example at the moment I write this comment, it's -5°F (-21°C) in Bismarck, North Dakota. And sub-zero Fahrenheit temperatures are pretty common in the winter across the Northeast, especially at night. "Normal" driving conditions extend way below just 20°F.

The charts should _all_ have the same range and scale so that they can be visually compared. As it stands they appear optimized for maximizing the data acuity of each individual car without consideration for visually comparing curves between cars.

Re: Winter & Cold Weather EV Range Loss in 7,000 Cars

#207

Do EV's keep their batteries warm electrically? I know some RV LiPo batteries have integrated heaters to keep the batteries from going below freezing. I suspect that's an acceptable tradeoff in cold climates. Ideally you would keep the battery warm while charging since it's more or less free power when tethered, and thermally insulate the battery enclosure to try to retain that heat as long as possible.

That doesn't sound very practical; keeping the batteries of all cars warm 24/7 would require immense amounts of electricity on a country-wide scale. It's not like everyone have heated garages, and outdoor temperatures often reach -30c or below in arctic climates.

1) the batteries are insulated

2) you don’t need to keep them warm 24/7, just above freezing when charging them or and/or when you want more efficiency or maximum power (like a longer trip, or midway through a drive).

ICE engines are quite inefficient when ‘cold’ (and diesel may refuse to run at all), this isn’t a new problem.

The batteries don’t need to be warm by human standards, and the vehicle will still work even when quite cold, just not very well.

Re: Winter & Cold Weather EV Range Loss in 7,000 Cars

#208

Earlier quoted context omitted.

Your car doesn't feel wind chill. I drive an EV in Canadian winter all the time. Not at all an issue. Range loss is a thing but it's not like the car stops working. In fact it starts more reliably and heats up more quickly for me. And I start mine remotely while it's still plugged in, so the cabin is warm and ready to go without wasting battery energy. And can do this safely in the garage without concerns of carbon m…

> They're only useful as a relatively subjective measure for people who aren't dressed properly. That's a bizarre thing to say when to dress properly, you need to know the wind chill. If it's 25°F out no wind, vs. 25°F out but it's 5°F with wind chill, that's an entire additional layer I need to put on during my morning walk. Wind chill is a very accurate measure for judging what to wear. How do you think it's not ac…

But if you only know the windchill temperature, how do you dress? If it is 10f with wind chill, do you prep for wind or not? I want to know temperature and windspeed, and then I know how many layers of wool I need (from the temperature) and how windproof I need to dress (from the windspeed).

Re: Winter & Cold Weather EV Range Loss in 7,000 Cars

#209

Earlier quoted context omitted.

An EV battery is entirely different than a lead acid accessory battery in a combustion car. It has a whole system dedicated to maintaining its temperature within ideal ranges. They don't die in cold weather. I've never heard of one doing so. The only issue with cold weather is reduced range. So just make sure you buy one with a battery big enough to handle your commute even with reduced range in cold. Which is pretty…

Phones and laptops get worse battery performance in cold weather and use similar batteries to EVs.

Those don't have "a whole system dedicated to maintaining its temperature within ideal ranges" although now you've got me wondering whether a laptop that expends some energy to keep its battery warm would actually last longer in extreme cold than an otherwise-identical laptop that doesn't... of course one would need to also consider whether the keep-warm energy is drawn while plugged in (which would obviously let it last longer) or not (which I'm not sure about).
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