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We all know of charging times and range reduced in colder weather, but what accelration performance? I have never driven in sub zero conditions but under hard accelration I find there is not a huge difference between hot and cold weather conditions.

Does the cold have much of an effect on this?
 

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Zoe Devotee
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I've noticed in my MG that you don't get 100% performance in extreme cold. I never noticed it on the Zoe but then it did only give you 100% power for about 3 seconds from pulling away then it would start reining in the power as you accelerated.
 
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I noticed a significant drop in peak acceleration in my Peugeot Ion if it was sub zero and especially if the car had been left for a couple of days over the weekend for the traction battery to cool right down to ambient. I'd say it knocked 20% off the acceleration as it was very noticeable. However I've noticed no change in acceleration in my Leaf 30 in sub zero temperatures.

So I'd say "it depends" on whether the battery on a given model EV is the limiting factor for peak acceleration or not - if it is then there might be a drop in cold weather when the cells internal resistance goes up and voltage drop under load increases, but if the battery was not the limiting factor then there may be no change, as the drive inverter electronics and motor itself will actually be happier and slightly more efficient in the colder temperatures due to lower resistance of windings and interconnects.

Charging times increase in cold weather because the rate you charge a Lithium Ion battery has to be reduced as it gets colder to avoid Lithium plating of the graphite electrode - allowing this to happen would cause cumulative and irreversible damage to the cells which can eventually lead to dendrites and short circuits. (Battery go boom...) So BMS's all progressively limit charging (and regen!) rates as it gets colder, and they play it really safe.

Fortunately there is no such limitation in the discharge direction or we'd all be driving really slow in winter. :) You can discharge a Lithium Ion battery at normal rates even at very cold temperatures without damaging it - sure, you'll get increased losses due to the higher resistance, and you can't discharge it as deeply when it's very cold, (some capacity at the bottom becomes unusable) both effects will reduce range, but the battery won't be damaged by high discharge rates in the cold, in fact high discharge rates will warm it up and bring it into a more comfortable operating range where it becomes more efficient and can charge/regen at a higher rate again.
 

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Speak, Eevee!
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Can't say it's something I've ever noticed, but in any case it's not like it's a Tesla when it comes to acceleration. It's superb compared to an ICE at 0-40 like any EV, and then it's.. well, a reasonably priced car :)
 
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dunno specific on each car's BMS. but lithium batteries USUALLY shouldnt be charged (and if so, should be done super slow) if temperature is 0C or lower, while most of them that say to not charge under 0C, say its ok to DISCHARGE at down to -20C. so they're usually safer to discharge in the cold than charging. So i would be more worried with hooking to a fast charger at -5C than to do a 0-60 at -15C

I'm obviously omitting that many cars have ways to warm up the batteries
 

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2020 Zoe ZE50 135 GT Line
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I haven’t really noticed a drop in performance, and with the continuously damp roads at the moment I’m definitely wheel spinning more when pulling away.

It's still blisteringly fast for me, but then I used to drive a VW Up with a 0-60 of around 14 seconds!
This is the most powerful car I’ve owned, even the Galaxy’s extra 1hp cant help it beat the Zoe to 60mph. And that is a torque’ diesel!
 

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dunno specific on each car's BMS. but lithium batteries USUALLY shouldnt be charged (and if so, should be done super slow) if temperature is 0C or lower, while most of them that say to not charge under 0C, say its ok to DISCHARGE at down to -20C. so they're usually safer to discharge in the cold than charging. So i would be more worried with hooking to a fast charger at -5C than to do a 0-60 at -15C

I'm obviously omitting that many cars have ways to warm up the batteries
I wouldn't be worried. The BMS monitors the cell temperatures and knows the safe operating area for the cells charge rate vs temperature. It won't let you harm the battery charging it cold. It will just reduce the charge rate to the point where it's safe or stop you charging.

(Or in EV's with battery heaters, heat the battery for a while before starting to charge...)
 
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