Under the terms of the new warranty, Nissan will repair or replace the Leaf's lithium-ion battery if the 12-bar capacity gauge falls under nine bars, which represents a 70 percent charge. The warranty is good for five years or 60,000 miles, whichever comes first.
Nissan is being cautious and it has made it clear that the goal of the fix is to return capacity to a minimum of nine bars, not to restore all 12 bars.
"The intent of this warranty is to provide consumers with confidence that despite this normal battery capacity loss, they will be assured of a minimum level of capacity throughout the warranty period," explained Andy Palmer, Nissan's executive vice president.
In addition to the extended warranty, Nissan says that it is looking at ways to make the Leaf's battery gauge more accurate.
The warranty will debut on the 2013 Leaf but it will be expanded to cover all 2011 and 2012 models before next summer.
For the time being the extended warranty only applies to cars sold in the United States. Nissan will offer it Japan and select countries in Europe in the not-too-distant future.