Nissan investigating reports of 30kWh Leaf battery degradation

Nissan says it’s investigating allegations of excessive degradation in Nissan Leaf 30kWh batteries.

A thorough internal investigation is being held, Nissan New Zealand managing director John Manley told The Listener following its story on the issue.

An automotive industry meeting is planned to discuss the battery matter and whether it is a global issue, first raised in a Flip the Fleet report.

Flip the Fleet, a national ‘citizen science’ coalition of more than 640 electric and plug-in vehicles owners who share data on the performance of their vehicles in New Zealand, says it has fielded an increasing number of queries by concerned 30kWh Leaf owners during the past three months.

The owners noted a fall in their battery state of health (SoH) or bars. Flip the Fleet enlisted help to get more battery scans. Its statistician, Dr Daniel Myall, and others in the organisation analysed the data.

Their report was released on March 16, alleging some of the 30kWh Leaf battery packs at two years of age are reportedly degrading at about three times the rate of the 24kWh variant, and this appears to be accelerating.

Flip the Fleet says it alerted Nissan and provided a draft report, estimating about 600 30kWh Leafs are on the road here with at least another 180 due.

“We do not know for certain what the underlying causes of the observed rapid decline are,” Flip the Fleet says. It suggests a combination of elevated temperatures while the battery is highly charged may be among the factors.

Flip the Fleet says rapid charging alone cannot explain the observations.

Insufficient testing has been done to determine whether range is affected, it says.

“We advise all buyers of any EV model to always get a battery scan check before purchase, where possible.”

Consumer New Zealand says it believes owners with cars exhibiting this problem have a case for recourse under the Consumer Guarantees Act.

Visit flipthefleet.org and preprints.org/manuscript/201803.0122/v1

for more information.