Livin’ La Vida Eléctrica

The New York Times offers a breezy article, Living With an Electric Car:

… Jackie Eskin, a computer consultant in Fairfield, Conn., who works from home, loves her Nissan Leaf battery electric, which she has been driving for six months and 2,000 miles. “I’m extremely happy,” she said. “It’s wonderful, and I love it.”

Before Ms. Eskin bought her car, she kept track of how many miles she drove each day and found it was rarely more than 15. That convinced her that she could live with the car’s 73-mile Environmental Protection Agency range rating. “I haven’t really experienced range anxiety,” she said. Her major issue with the Leaf? It doesn’t have a sunroof.

Paul Beerkens, a Chicago-based programmer for a hedge fund, also owned a Leaf, but traded it in after only six weeks. He told a reporter for (to which this writer also contributes) that dying batteries almost left him stranded during a snowstorm with his children in the car, so he bought a plug-in hybrid Chevrolet Volt. …

Dr. Michael Rabara, a Phoenix psychologist, isn’t likely to encounter a snowstorm, but he sold his Leaf because, he said, its battery pack showed signs of capacity loss after 10,000 miles in the Arizona sun. The Leaf’s 24-kilowatt-hour battery pack is air-cooled and lacks a liquid temperature management system like those in the Tesla Model S and other electric vehicles.

In Consumer Energy Report, Russ Finley attempts to tamp down Nissan Leaf Range Issues:

This test would never pass muster in the world of science, where a hypothesis is proposed and tested using methods to minimize researcher bias. These guys were out to prove that the capacity of their batteries had been reduced by exposure to extreme heat beyond what the published specifications would predict. When any researcher sets out to prove he’s right, he will invariably manage to do so, at least until his research is peer reviewed or attempts are made to duplicate results. That is why the scientific method was invented.

There is a simple, relatively crude gauge, in the Leaf dashboard to warn owners when their battery won’t hold as much charge as it did when new. Nissan has suggested that some of these gauges may be out of calibration (possibly because of the extreme heat) and may be providing overly conservative estimates of battery life. Lo and behold, one of the cars in the test with a gauge indication of just 10 bars out of 12 went further than any other car.

The fact that more than one of the twelve cars tested by the Leaf owners had gauges that were not accurately indicating battery capacity suggests that a significant number of  Leafs may have gauges that exaggerate battery capacity loss.

In short, this paper failed its peer review. The test actually proved that:

1. Out-of-calibration gauges really are contributing to misperceptions.
2. All but two of the twelve cars thought to be damaged were actually performing within or just a few percentage points outside of the range band stated in a published Nissan technical bulletin (76 to 84 mile range when consuming energy at a rate of 4 miles/kWh at 70 degrees F ambient air temperature).

In the comments section, however, Tony Williams and other owners fire back:

Tony Williams: Your references to the EPA LA4 cycle tests that show the LEAF going 100 miles, or more, just do not reflect reality of the average consumer. As you know, these tests are not conducted on a road, but are instead are run on a chassis dynomometer to simulate driving in those prescribed conditions. That’s not to say that you can’t drive 100 miles in a LEAF; I’ve done it exactly twice. Both times were difficult exercises that the average consumer will not do. About 41 drivers have chronicled their successful milestone of 100 miles on the “MyNissanLEAF” forum, out of more than 13,000 LEAFs in the USA to have a chance at that milestone. I’ll bet that neither you, nor Mr. Larsen, have actually driven a LEAF 100 miles. It’s easy to say; not so easy to do, nor is it typical.

I do agree that “out-of-calibration gauges really are contributing to misperceptions”, and make reference to that in the paper. I’m not sure why you suggest otherwise. That’s not to suggest that those batteries are OK; it’s not an either/or situation. Both the instruments are faulty, and the batteries are degrading quickly.

Since you reference Mr. Larsen’s claim that 76 miles should be used in lieu of 84 miles of range for a new LEAF, per the Nissan technical bulletin that I reference (76 to 84 mile range when consuming energy at a rate of 4 miles/kWh at 70 degrees F ambient air temperature),  let me just say we disagree. The LEAF is fully capable of 84 miles when new at 4.0 miles/kWh, and I have demonstrated that MANY times outside this test. Granted, it’s an omission in the test, but again, we worked within the limitations presented us. The biggest limitation was not having a SINGLE car that could reach 84 miles. That doesn’t mean they can’t; they did when new on the factory floor in Japan.

Paul Seppuka: I am the owner of Blue917 from the Phoenix test and I have a battery pack that will require replacement, when it’s remaining capacity reaches 70%, after only 30 to 36 months of driving. What a far cry from the 5 to 10 year estimate Nissan advertised. I drive the national average of 1,000 miles a year (32 miles a day). Currently I can travel 45 miles of mixed city/highway driving at 4.5kw/mile to  low battery warning on the 80% charge Nissan recommends. When the car was new, I regularly obtained 62 miles of range under very similar driving conditions. That’s only 72% of my original range from new after only 15 months and 15,000 miles of driving. Nissan can’t explain this loss to me (as a matter of fact, they state it is normal), maybe you have some ideas? …

George-Leaf: Russ, I have been a Leaf owner for about 18 months now.  I am neither a fan boy of the Leaf or a hater.  I think it is a very good first attempt at a mass market EV.  I have been watching the hot climate range issue very closely.  Your article comes across as an attempt at objectivity but written from the position of a bewildered defender, someone still in the throws of trying to make sense of something you haven’t totally come to terms with.  from everything I’ve read, it is absolutely clear that a substantial number of people in hot climates are seeing what can only be described as rapid capacity loss, not gradual.  When I bought my Leaf, I asked about heat and the battery’s longevity before signing the “gradual capacity loss” admission.  I was told then and have heard repeated since, that there was a Leaf on a race track near Phoenix (casa grande) that Nissan was driving continuously and quick charging continuously and that “even in one of the hottest places on earth”, it was showing no battery degradation.  This claim must have been part of the original PR that Nissan fed to it’s salesman because it was repeated in more places than the dealership I went to.  Then there was also the story of the Leaf taxi in Japan that was being nothing but quick charged, with no ill effects.  As a prospective buyer, I was assured that the Leaf’s batteries were the result of $4 billion in research and were superior to anything on the market, robust enough to take just about anything a US driver could throw at them and that they just simply didn’t need temperature management because of advancements in battery chemistry.  After going through a couple seasons now, I can no longer agree. …

John Hollenberg:The whole premise of this article is that the range of a new Leaf is only 76 miles at 4 miles per kwh.  This implies usable energy from the battery of only 19 kwh.  A number of tests have shown the range to be 84 miles at 4 miles per kwh.  Now we have validation from the NREL, which found usable energy of a new Leaf to be 21.381 kwh.  This would suggest a range of 85.5 miles at 4 miles per kwh. …


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5 responses to “Livin’ La Vida Eléctrica”

  1. Yanquetino says :

    I see that you have included the comments that many of the usual suspects posted in Finley’s article to dismiss my analysis. I suppose it is about time I responded to those criticisms.

    For the record, my only purpose in examining the owners’ test data was to compare the actual ranges achieved with the parameters postulated by Nissan.

    To reiterate, in its Technical Bulletin NTB11-076a, Nissan states that a brand new Leaf should achieve a range of about 76-to-84 miles at 4 miles-per-kWh. As for capacity loss, the automaker has repeatedly predicted that it will drop to about 80% after 5 years, and around 70% after 10 years. Those benchmarks plot a polynomial curve, and the equation for the trendline generates corresponding percentages of capacity loss from month-to-month and mile-after-mile.

    For example, said trendline predicts that Paul Seppuka’s Blue917, with 14,000 miles on its odometer, should have achieved between 71.5 and 79.5 miles on the owners’ test. It actually went 72.5 miles in the experiment. How, then, can one claim that its range is not within Nissan’s “normal” parameters?

    I have never ventured to theorize about why Nissan would declare those particular benchmarks and range predictions. I have simply taken the figures at face value and applied them to the data gathered. Had the results shown that all the test Leafs had fallen below the trendline ranges, I would have declared as much. But they did not. It is a question of math, not personal bias.

    Mark D Larsen


    • Donal says :

      The “usual suspects” are, of course, people enthusiastic enough about electric vehicles to believe the advertising and actually buy one. Nissan now claims only 68 miles at 49 miles per hour on a hot day. Had they claimed that from the beginning, they’d probably have fewer complaints now, but probably fewer sales.


      • Yanquetino says :

        Hi, Donal:

        To be clear, I am among those “enthusiastic enough about electric vehicles” to “actually buy one.” As for advertising, it is true that from the outset Nissan boasted a 100-mile range. However, if memory serves, they always qualified that estimate by clarifying that it was based on the LA4 test cycle, and that (like all OEMs state) “your mileage may vary.”

        I am perplexed, however, by your adverb “now” for the 68 miles of range at an average speed of 49 mph (Nissan’s “Scenario 2: Cross-Town Commute on a Hot Day.” I seem to recall that Nissan provided those 6 different driving “scenarios,” with ranges from 62 to 138 miles, very early on. I even remember filling out a customer survey in which Nissan described those scenarios, about a month before the rollout began. Had you not seen them before? They are, by the way, what I use in my “Capacity Loss Tables”:

        I would agree that Nissan should have made those various range estimates much more visible, rather than relegate them to mere footnotes or pop-open windows on the website. Indeed, I have always felt that they should have advertised the official EPA estimate of 73 miles for a new Leaf –rather than the LA4 test cycle range. I am very glad to see they are now doing just that:

        Still, the bottom line is that Nissan did provide figures for capacity loss and estimated ranges, and the majority of the owners’ test Leafs fell within those parameters –despite the exaggerated degradation that their gauges were showing.

        In that regard, I can’t blame the owners in the least for being alarmed: it was only logical to assume that those capacity bars were reliable. That would have been my default conclusion had I suddenly noticed that one was missing! However, now that their test results have shown otherwise, I would hope that they’d feel relieved and reassured to know that, as company confirmed with its own analysis, their Leafs “are behaving as we expected.”

        Gotta tune up those gauges, Nissan! Otherwise, how are drivers to know that the readouts are not to be trusted?


        • Donal says :

          I first heard tell of a 100 mile range, then read articles doubting that. At the DC Auto show. I was told 70 or 80 with the (original) heater or AC, or when driving at highway speeds. After hearing about the range loss issue, I read the Nissan sales site and saw an even shorter range of 68 miles at only 49 mph. Tony says he was getting 84 on his x-country jaunt. So range seems like a moving target.


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