Level 3 Charge in very cold weather

Does anyone see any issues with using a L3 charger in extreme cold or very cold weather? By that I mean -5F - 20F approx temps? Worried the temp variations could possibly damage the battery.

By level 3, do you mean a CCS unit (level 3 isn't a valid designation, but sometimes mistakenly used for a CCS unit)?

I've not tried it, but it's my understanding that the logic in the car should be able to handle this...it may not charge as fast as it would at other temperatures. The car has both the ability to heat and cool the battery pack (but that does use more power from the unit to accomplish this).

I charged this afternoon on a level 3 CCS charger in 6 degree weather. Zero issues. Charged normally. I was preceded at the charger by a Model S and succeeded by a Bolt. So this is totally within spec of all EVs, presumably.

As jadnashuanh stated, there is no Level 3 charging standard yet, but a DC Level 3 standard is under consideration. It could very well be a 900 V standard or a very high current 450 V standard, neither of which an i3 could utilize fully. The current DC fast charging standards are DC Level 1, 200–450 V DC up to 80 A or 36 kW, and DC Level 2, 200–450 V DC from 80-200 A or up to 90 kW. An i3 can use either DC Level 1 or 2 but can utilize only up to 50 kW with a DC Level 2 charger.

So mentioning Level 3 charging now is meaningless and could be confusing when a DC Level 3 standard exists.

I don't have technical details on the charger but I do know it can shell out about 48KW if that helps. It's definitely a DC Fast charger. I used it and didn't have problems and I did notice in the cold it was seemingly only injecting about 25KW max even at a low state of charge so perhaps there is some logic to protect to batteries in extreme cold and heat when charging.

The act of charging warms the batteries, which is why starting with a hot one is much more problematic than a cold one. But, the chemical process of charging is slowed by them being cold, and charging a hot battery too fast can overheat them, causing issues. The only time where a super cold battery is an issue is if you leave it that way in a cold environment. When you drive up to a CCS unit to recharge, the odds are that you've just been driving the car for awhile, and the batteries are warmed by that use and the battery management system in the car...thus, ready to accept a fast charge. The CCS unit may have slowed down for numerous reasons, and only some of them are related to the car...they do get hot on their own, and after pumping out that high current DCV, while the car might have been able to accept it, the CCS unit may have throttled itself down to cool itself off. That's generally more of an issue when it's hot...it's cooling capacity isn't as efficient.

After all, a CCS unit is essentially a smart, high-powered, variable DC power supply...there is some loss in converting from ACV to DCV and that heat needs to be managed whether it's in the CCS unit or the car itself. The reason the i3 is limited to 7.4Kwhr when using an EVSE is for the same issue...the conversion of ACV to DCV creates heat, and that's the maximum they wanted to deal with on the i3.