Nissan LEAF Battery Degradation Actually A Software Glitch
Nissan Addresses Inaccurate Battery Range and State of Charge Reporting
In case you missed this, last month Nissan released a statement (and a fix) for the 2016 and 2017 30kwh LEAFs that were supposedly experiencing premature battery degradation. Essentially these cars were, on the face of it, losing range and capacity at an accelerated rate.
Owners of these EVs were reporting that their cars were losing as much as 25 percent of their car’s range and battery capacity in as little as 15,000 miles. True, Nissan’s 96-month/100,000-mile lithium-ion battery capacity coverage replaced the suspect batteries but that apparently wasn't a permanent fix.
It transpires that the BMS system provided inaccurate calculations used to determine the state of charge (SOC) and ultimately the range available from the battery.
Now to be clear, measuring the battery capacity of Lithium cells can be difficult as capacity is not absolute and highly dependent on the use. In short, the lower the current drain the more capacity they will yield. That said, other manufacturers manage this perfectly fine it's just that Nissan obviously made a mistake this time around. Nissan has historically been broadly criticised for the method it uses to manage the health and heat of the Leaf lithium-ion batteries.
Note: It's possible not all dealers may not be up-to-date on this campaign. Please refer to Customer Service Campaign ID:PC630.
Nissan Customer Service Campaign Statement
On June 6, 2018, Nissan began conducting a customer service campaign in North America to reprogram the lithium-ion battery controller in 2016 and 2017 model-year LEAF vehicles equipped with a 30-kWh battery, to correct the calculation used for the battery capacity level gauge and distance remaining of the vehicle.
The displayed vehicle range and battery capacity level gauge on these vehicles are displaying range and capacity that is lower than the actual amount. Reprogramming the controller will result in an accurate display of the LEAFs battery capacity and trip range.
This service campaign is open to all 2016 and 2017 LEAFs regardless of mileage or if they have had their battery previously replaced. Owners should contact their local dealer to schedule the update. After the reprogramming, the balance of the original lithium-ion battery and battery capacity warranty will remain in effect for any customers who experience warrantable battery degradation.