# Battery temperature gauge in red after fast charging (or a long day of driving)?

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Annoyingly difficult to avoid highways with 70mph limits with some of this, at least typical navigation isnt much help.

Yep

For the last part of my mini-series in how to live with a LEAF outside or local commuting, here is a bit of LEAF physics (love it or hate it!)

Power is proportional to the cubic increase in speed
Example: doubling the speed will require an 8x increase in power
Heat generation in the pack is proportional to Power

Let's look at 70 mph Vs 65 mph
Driving at 70 mph will generate (70/65)^3 = 125% more heat generation than 65 mph and you will go 70/65 further.
So while not exact for reasons I will not go into, it is approximately true that driving at 65 mph will let you drive (70/65)^2 = 1.16 = 116% further than at 70 mph within the same temperature budget

A 200 mile drive at 70 mph can be an ~ 230 mile drive at 65 mph (as limited by pack heating), with the trade-off being more traveling time of (70/65)x

There is quite a bit more that can be mentioned, but hopefully this is enough to get you back on the road. We'll talk again when wind foils your best laid plans.

I follow the slow trucks at a polite distance, at least 70', usually 100'.

I don't get any aerodynamic benefit, but the psycho/social payoff is striking. It is mind-boggling how much hate you can get for driving slower than the crowd... we're still talking 60 - 65 mph, when everyone else is going 70 -80 mph.

But everyone can see the big truck in front of me going slow, so they get in the passing lane and don't give me a second thought.

I don't get any aerodynamic benefit,
I've thought there was still some aerodynamic benefit when doing that, even if it's not dramatic. Say I'm following a ~60-65mph rig for a while at what seems to me a respectful distance, then back off a few mph to let the truck get farther ahead. I've noticed a couple of times the "power meter" in the console showing higher consumption rather than decreasing the way I'd expect. I'll have to pay attention and see if it's consistently that way or just a fluke from where the hills were or whatever.

At 25 MPH and over 400hp working to drag it, I'd be more worried about rolling backwards before I could get off the throttle and on the brake.
lol. Fair enough. Perhaps that’s why convoys aren’t so much of a thing anymore.

I follow the slow trucks at a polite distance, at least 70', usually 100'.

I don't get any aerodynamic benefit, but the psycho/social payoff is striking. It is mind-boggling how much hate you can get for driving slower than the crowd... we're still talking 60 - 65 mph, when everyone else is going 70 -80 mph.

But everyone can see the big truck in front of me going slow, so they get in the passing lane and don't give me a second thought.
Needs to be more like 30’ for it to really work. Or it did. Cars are a lot more aerodynamic now. When it really works you can actually hear it. The wind noise mostly goes away. My dad had a CB in his car. We were always in back. Dad had a diesel vannagon. Weighed nothing relative to everything else, and it had brakes from a heavier faster vehicle. To call the thing a dog was massively inadequate. Thing wouldn’t hit 50 in a good headwind. Merging onto the freeway was downright dangerous. It was designed to be a night bus in German towns and never go over 50kph. Stopped fine though.

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I'm quite familiar with the aero behavior when I'm in the pocket. That just pisses people off.

I want to drive the speed limit without getting killed.

One time, I was doing 65 and the teen in a Compass behind me was doing 75 without paying attention. I was so happy we both didn't die.

Another time, I was towing and a kid in a Grand Prix went right up onto my trailer. I even had my hazard lights on. Again, distracted.

I'm quite familiar with the aero behavior when I'm in the pocket. That just pisses people off.

I want to drive the speed limit without getting killed.

One time, I was doing 65 and the teen in a Compass behind me was doing 75 without paying attention. I was so happy we both didn't die.

Another time, I was towing and a kid in a Grand Prix went right up onto my trailer. I even had my hazard lights on. Again, distracted.
One I saw recently was pretty stunning. Dude stopped at a stop sign and then rammed a car passing through. I was told it’s called a roll thru. What was amazing is it apparently happened because the guy was watching videos on his phone. He was still doing it when he got out of the car, and only paused it to talk to the other driver (who was of course royally pissed) he actually said it wasn’t his fault. I stopped and offered to corroborate testimony to the guy he rammed.

I've thought there was still some aerodynamic benefit when doing that, even if it's not dramatic.
Mythbusters did an episode on that. Apparently there's much benefit when following closely but that's obviously dangerous (and annoying), but the benefits gradually diminish for a surprisingly long distance.

Interesting. I’ll have to look that up