The Case Of The Missing Bars: Leaf Owners Stage Massive Test To Prove Premature Battery Aging

Earlier this year, Nissan Leaf owners in Arizona started to observe bars missing from the charge state display of their cars. Instead of the 12 bars that signal a full battery, some saw only 10 or less. This spread like the Arizona wildfires through the EV community. As of today, the discussion at the Mynissanleaf forum has swelled to 373 pages. Nissan looked at the affected cars, and so far has not rendered a verdict. Or maybe it did. 12 Leaf owners did assemble one night to prove Nissan wrong.

Three weeks ago, Nissan’s Executive Vice President Andy Palmer was quoted by Australia’s Sydney Morning Herald as saying that “we don’t have a battery problem” and that the battery level display is faulty. Enraged, the Arizona Leaf owners set up a massive test, and published the results at InsideEVs.

12 Leafs with odometer readings as low as 2,500 miles and as high as 29,000 miles assembled at night at 7755 South Research Drive, Tempe, Arizona. The location was chosen because it has a DC Chademo fast charger, and two J1772-2009 EVSE charging stations. From there, they did set out to drive the Leafs until the battery runs out, or more exactly, until the Turtle in the display strongly recommends to get off the road. They even had a small fleet of dollies and a flatbed truck to collect the exhausted Leafs.

The results of the test appear to support the group’s claim that the Leaf’s batteries degrade much faster than they should, at least in the hot climate of Arizona. A Leaf with 29,000 miles on the clock did last only 59.3 miles during the group’s test, a nearly 30 percent degradation from the 84 miles the group says a new Leaf should get. A Leaf with only 2,500 miles on the meter did last nearly 80 miles.

The test was professionally set up, VERY detailed description here. The group also measured the charge indicator, and found that in most cases, the instrument low-balls the available charge. Says Tony Williams who spearheaded the effort , and who had done an all-electric Canada to Mexico trip in a Leaf:

“So, Andy Palmer was right… they have poor instruments. But, he was wrong about the batteries. It was sheer stupidity to tell this group of owners that the batteries are ok. “

We talked to Nissan’s General Manager of Global Communications, Jeff Kuhlman, in Yokohama. Kuhlman praises the affected owners who “are very knowledgeable, some are engineers themselves.”

He denies that Nissan has come to a conclusion on the matter: “We cannot give you a final analysis, because there simply is none available yet.”

Seven affected Leafs were inspected by Nissan , and subsequently returned to their customers. Nissan did a full data download on all units.

“The data are with our technical team in Yokohama, and they are still analyzing them,” says Kuhlman. “Once they have finished their analysis, the owners will be contacted first, and we will discuss with them what needs to be done.”

Kuhlman expects the verdict to be available “within days.”