thebishman

"I have driven that stretch of I-5 many many times, and Tesla drivers are usually flying along with everyone else. This time around it wasn't like that. Even the EV's that were going faster were hanging around the 70mph speed limit. I didn't get passed by an EV while I was driving through the valley in both directions. That's unusual. And I was keeping it around 75-80 for the most part when traffic allowed it. I don't think I saw a single etron the entire time. I saw plenty of them in LA and Sacramento, but not in between. Other than Tesla's, I saw a few Kia's, and one of those BMW i3's that makes me laugh every time. Wow, that drive must have been a struggle in that car. Hopefully they weren't going very far. The Kia's were going slow. Of course the i3 was going slow. It had to have been the heat. From the limited reading that I have done, it sounds like these cars are more or less unaffected up to a point due to liquid cooled batteries and other features, but when you get into the 115+ realm it starts to become an issue at least with some of them. Someone in Dubai was commenting that the range on their Tesla is noticeably affected when it's 115+. That's pretty extreme though, and what I experienced on Sunday was also a pretty extreme event. Las Vegas hit 120 that day which broke the previous record by three degrees. Redding set a new record at 119. Death Valley reached 128, and lived up to it's unfortunate name by claiming a life. Heat like this isn't something that the vast majority of the country has to worry about. I just thought it was interesting watching these cars get tested in unusually harsh conditions. I think it's also important to point out that I didn't see any EV's on the side of the freeway. I did see some broken down ICE vehicles, but no EV's."

I really think that the major takeaway from your post and observations is summed up in one word: 'Tesla'.

I believe that the BMS in Teslas is still a very poor relation to the one in the etron and/or my iX. We know for a fact that the range a Tesla will actually obtain at typical highway speeds even in perfect conditions is much less than advertised, whereas the etron normally can travel the range stated by the GOM at the start of a journey, and my iX generally gets better range than its EPA rating; (much better tbh).

We've been having the same conversation on the BMW iX forum re: range effects in extreme heat, and most owners seem to feel that they're losing perhaps 5% in range with these temps in the 100's, but whether that is partly due to the A/C running in a higher state versus some form of battery inefficiency is debatable.
__________________

JNealCox

Range-wise, lithium batteries are even more sensitive to high temps than low. The etron turns on active cooling when the battery temp gets close to 100F.