How pervasive is the problem of battery capacity loss in the Nissan LEAF?
To recap for those just joining this discussion – this is the third in a series of articles regarding the issue of battery capacity loss in the Nissan LEAF. Our first two articles can be found here (first article) and here (second article). This discussion thus far has covered over 250 pages on the My Nissan LEAF forum. We are working our way through every post from the first to try to better understand the issue from the owner’s perspectives. Thus far we are up to page 80.
As we continued our reading of the My Nissan LEAF (MNL) forum topic regarding the battery capacity loss issue of the LEAF, we found as each week went by other LEAF owners were reporting that either they had lost a battery capacity segment, or some reported of knowing others that had. Near the end of these posts, we read a brief post indicating that 17 of roughly 25,000 LEAFs sold world-wide (the then current number affected by the problem) accounted for less than one tenth of one percent of all LEAFs produced. According to the forum wiki, the number is now up to 54. No doubt this discussion has progressed in future pages, which we will read eventually, but this did provoke a response from several forum members that the universe should be confined to Phoenix or even just Southwest area owners. The individual that made the original post stood her ground and said that the proper universe should include all cars sold globally as it is not known if similar conditions exist in other areas. She also made another extremely important observation – we don’t know how many or where other LEAFs may be impacted by this same condition, which is why all LEAFs sold must be considered in the sample universe.
In reviewing the latest list of one segment battery capacity lost owners, the geographic universe now includes a handful in Texas and California along with the rest which mostly reside in Arizona. Of the California cars, one report is from the moderate climate of San Diego, which goes against the hot climate theory. In reviewing the notes accompanying the San Diego car’s wiki entry, this particular LEAF accumulated over 25,000 miles in 14 months and the battery was drained to “turtle” mode about 20 times in that 14 month period. Given that this is only one example, one must consider the possiblity that frequent use of the entire usable battery capacity may also be a contributing factor to this issue. Then again, accumulating 25,000 miles in 14 months and using the entire usable battery capacity perhaps 20 times during that time frame is likely outside the norm regarding typical vehicle usage. (EDIT: Based on a comment to this post, and upon reviewing the original post by the owner, this San Diego car did not lose a bar as reported. The owner thought it was about to lose a bar when he sold it.)
In looking at the MNL wiki, it seems that one column of the table is now formatted for “Case Number”. As there is no legend to the table on the wiki page, we can only assume that these are Nissan case numbers assigned as these cars have been reported to Nissan.
Getting back to our original question – how pervasive is this problem? The only entity that knows that is Nissan. And we don’t know if they are fully aware of all of the vehicles impacted if the owner has not notified them. But let’s get hypothetical for a moment. Let’s just say that as many as 200 vehicles are impacted globally. That number is still less than one percent of all LEAFs sold globally to date. Which means that more than 99 percent are not impacted. Certainly this number will continue to grow, and we are not attempting to sidestep that part of the equation. But as it stands now, statistically speaking, this is still a very small percentage or even fraction of a percentage of the entire universe. And this is the point that all Nissan LEAF owners or prospective LEAF owners must keep in mind. A statistical outlier is called that for a reason – it is not the norm. And based on the number of case numbers (31 at last count) that we saw posted on the MNL wiki of LEAFs reported on the MNL forum, Nissan is taking this seriously.
It would be unreasonable to expect a resolution in a week or two. Granted, it has been much longer than that since the first reported case on the forum in May. Early problems were reported to local dealers, but we don’t know if those local dealers were reporting anything further up the food chain. Nissan North America may not have been made aware of the problem initially. Now the corporation has been notified, by at least 31 LEAF owners, and Nissan is looking more closely at each of these situations. With the financial commitment that Nissan has made to the success of electric vehicles globally, one can be certain that they are commiting vast resources to the study of these vehicles and their use history. We imagine that each battery pack is being evaluated cell-by-cell to determine if it is a manufacturing defect or an issue of chemistry. Nissan will also closely examine the vehicle usage history to see how closely owners complied with Nissan’s recommendations regarding battery care. For those LEAF owners following this saga carefully, we will refer you back to our prelude to this series – Care and feeding of the Nissan LEAF battery.