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Taking Your Old Leaf On A Summer Road Trip - Don't Do It


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Special To The Auto Channel
From Author Jennifer Sensiba
Contributing Editor

In past articles, I’ve had some pretty tough things to say about the second generation Nissan LEAF. The #Rapidgate issue, where the passively-cooled battery heats up and charging rates slow down more than previous generations, was a particularly bad one. Customers familiar with the first generation LEAF didn’t know that the vehicle was going to slow charging down, and it made life hard for many owners in the summer. In warmer places, the unexpected issue hurt the LEAF experience for most of the year.

I changed what I was doing for a living in 2019, around the same time as Nissan released the software update. I had also moved, and there just weren’t many DCFC stations in the area to give the vehicle a good test with. Then, the COVID-19 pandemic came along and kept the LEAF grounded quite a bit in 2020 and so far this year.

Since 2019, the buildout of Electrify America’s network changed the EV charging landscape, even in west Texas and southern New Mexico. Instead of zero stations, there are now stations all along I-10. It’s possible again to use my 2018 LEAF on some road trips. With Electrify America’s free charging on Earth Day, I had the opportunity to give the LEAF a fairly thorough test without having to spend any money on fuel, so I went for it!

The Testing

I decided on a road trip of about 250 miles with three charges. That many highway miles (with 75 MPH speed limits) and that much charging gives the vehicle an opportunity to heat up the battery, and then I can see if the software update helps with charging times.

Ambient temperatures were about 80 degrees for most of the trip, which should represent summer temperatures for places outside of the Southwest (this is late-spring weather here). There were some winds, but that wasn’t a huge problem, as I slowed down a bit to make up for it when I was heading into it and it helped the vehicle on the way back. I also aired the tires up to about 40 PSI to make sure that the vehicle would get decent efficiency. Air conditioner was set to 72, and didn’t run very hard.

I also let the vehicle and battery cool down to ambient temperatures before departing, to make the test as fair as possible.

For the route, I went along I-10 from Las Cruces, NM to Lordsburg, NM, and then back. That gives 244 miles of highway driving with three DC fast charging sessions along the way. #Rapidgate issues have usually cropped up in the past for other drivers on the second or third charges, so this was a good test to see if it gets better charging speeds in summer temperatures.

The Results

When I left, the temperature was at the halfway mark on the temperature gauge. I know from experience that if it’s below this temperature, it can get a full 50 kW charge rate, and with the software update could have done a 40-50 kW charge at that temperature. But, it was fully charged, so no need for that.

On the first leg of the trip, I kept things at about 70 MPH due to a 10 MPH headwind (with some gusts to 20). I picked up one segment on the temperature meter doing this.

I ate up 80% of the battery going 58 miles, and it estimated that I had 20 miles left. When I plugged it in, it gave me 40 kW of charge rate, which is better than the 28 kW charge rate it used to give me at this temperature. This tells me that the #Rapidgate software update does improve the charge rate some. Due to the headwinds, A Better Routeplanner recommended a 98% charge, and that took me just under 52 minutes.

On the second leg of the trip, things went downhill. At the start of the drive, the temperature gauge was at the top, but not in the red. By the time I was about halfway to the next charger (30 miles of driving), the power started cutting to prevent overheating. I kept the speed at about 70 MPH because the headwinds were still between 10 and 20 MPH, and I didn’t want to run out of charge, and this probably kept it from overheating entirely.

Despite slowing down below the speed limit like this, half of the power was cut by the time I reached Lordsburg, and the temperature gauge was in the red. Instead of plugging it right in, I decided to wait 5 minutes and let it cool down a bit, and during that time it got some of its power back but was still in the red. I had 16% battery remaining after driving only about 60 miles.

When I plugged in, I got a 14 kW charging rate, and estimated that I’d be here for about an hour and 45 minutes. I knew something like this could happen, so I brought my laptop along to work and everyone else had something to do. We ended up spending an hour and 24 minutes to get to 85% (enough to get back to Deming with a tailwind).

Departing Lordsburg and heading back to Deming, the battery was still in the red. The sun had set and temperatures had fallen about 20 degrees, and I was headed back east with a 10 MPH tail wind. I set the cruise for about 70 MPH, and watched the power meter slowly lose segments. 20 minutes later, it was almost to the point where it would go to “turtle mode” due to heat, so I decided to go ahead and drop to about 60 MPH. Fortunately, there was a slow semi-truck I could fall in behind so I wasn’t the lone person going that slow.

After another 40 minutes of almost getting run over by 80,000 pound loads that were going the 75 MPH speed limit, I arrived in Deming and the battery had cooled off almost out of the red zone. We stopped to get some water and snacks, and while it sat, it dropped just below red. When we arrived back at the Electrify America charger, we noticed an improvement in charging.

But, we only got 2 kW more, for a grand total of 16 kW. The car estimated a 55 minute wait to get to 80% (enough to get back to Las Cruces). We went from 22% to 85% in 1 hour, 5 minutes. Temperatures were back in the red, and the power was cut again, meaning I needed to cut my travel speed down again for the next and last leg of the trip.

Because temperatures had dropped into the 50s, I managed to go 72-74 MPH without further heating that would take it to turtle mode, but that was still below the speed limit. Unfortunately, I had difficulty going around a vehicle that was moving erratically because half of the vehicle’s power was gone, leaving me with no passing or emergency power. That actually scared me a bit.

I got home about 8 hours and 20 minutes after leaving. That means I drove 244 miles in 8 hours, for an average of about 30 miles per hour. Roughly 4 hours were spent driving, and the remaining 4 hours were spent charging. A gas vehicle or a much better electric vehicle would have done the same driving in 3 hours (3.5-4 if the EV has to stop and charge because it was going 80 and ran its battery down).

Conclusions

I’ve had this vehicle for three years and have driven it almost 70,000 miles, so I know it tends to overheat in anything but winter temperatures along the highway unless you obey the Japanese speed limit (62 MPH). The software did help it charge a fair amount faster at the first charging session on the trip, but once it overheats, it charges at poor speeds like it always has. Really, there’s only so much Nissan could do with software to make it better, and when it hits the red, there’s no room for faster charging without setting the thing on fire (which I wouldn’t break into tears over at this point).

If I was a new EV buyer and had just picked up the LEAF, I’d be pretty angry that it can only go about 70-75 miles at normal western American highway speeds and overheats. I’d be even more angry about long charging stops that make a road trip possible, but not pleasant or time efficient at all. New owners also don’t know to avoid overheating it to the point of activating “Turtle Mode,” and people in my family call this “Meeting Mister Turtle” (and no, his name is not Crush).

Basically, the LEAF has proven to only be remotely usable in the summer for highway trips of up to 100-120 miles round trip if there’s a rapid charger at the destination. Go any further, and you get to the point where it overheats and/or charges slowly and becomes a problem. In places where your maximum traveling speed is around 60 MPH (like most of Japan, where the car was designed), and in a relatively mild climate, the car probably does better.

I don’t live in Japan, though. I live in the Southwest US where it gets hot, and the speed limits are 75 (which means you have to go 80 along some stretches, or up the risk getting destroyed by a semi-truck). Vehicles that can’t keep up with the flow of traffic in a region probably shouldn’t be sold there, or at the very least, they shouldn’t be marketed as usable highway vehicles.

Nissan should consider ending LEAF production if it can’t make a third generation of the vehicle that doesn’t have these problems. It needs to have liquid cooling, more than 200 miles of range for the bottom model (to make it to the next station consistently), and a CCS plug for the US market. Anything short of that is not only bad for the company, but bad for EV adoption in general.

I’m financially stuck with the thing for now and will keep using it around town, but that doesn’t mean I’m happy with its limitations.

Featured image and all images in this article by Jennifer Sensiba.


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