Meanwhile, the Leaf is being outsold by hybrid rivals that have backup gasoline engines to take over after the electric charge runs out: the Chevrolet Volt and the Toyota Prius Plug-in.
Pricing is one hurdle.
The Leaf, which went on sale in December 2010 as a low-volume import from Japan, retails for $36,050, including shipping, and is eligible for a $7,500 U.S. tax credit. Its base price is below the Volt's but above the Prius Plug-in's.
It is unclear what the price of the new base trim level will be.
David Reuter, a spokesman for Nissan Americas, declined to comment.
Moving to Tennessee
For the past two years, Nissan has indicated that it intends to use the shift in Leaf production to Tennessee to bring costs down.
Switching from a Japanese factory line to an American one will allow the Leaf to escape the high costs of Japanese exports resulting from the strong yen.
In addition, Nissan is also bringing the production of the car's costly lithium ion battery modules, which represents a large portion of the Leaf's sticker price, in-house.
Nissan is days away from starting battery production in Smyrna, with a new $1.4 billion plant that has capacity to produce 200,000 battery modules a year.
Nissan has never clarified what other products those batteries might go into, including whether or not it might use Smyrna batteries to power an upcoming electric Infiniti sedan.
In addition, Nissan is asking suppliers to target cost reductions as high as 50 percent, according to one of the sources.
Said the other: "There is an enormous amount of pressure on cost."
Some of the streamlining will involve removing content for the entry-level model. Other strategies will include re-engineering portions of the car to cut costs by combining components.
For example, some electric drivetrain components now in the back of the car will be integrated with powertrain systems in the forward engine bay, one person said.
As part of the decontenting, the entry grade is also expected to skimp on the more advanced features offered in the Leaf's current navigation system.
And the entry Leaf will get traditional -- and lower-cost -- high-intensity discharge headlamps, not the high-tech, high-cost light-emitting diode lamps that now come standard.
The LED lights, with their aerodynamic design, were introduced with much fanfare for their low-energy consumption -- a feature deemed vital to conserving the Leaf's battery charge.
Bringing down the sticker is one way to bolster interest. But insiders say it is still uncertain how customers will react.
So far, most of the Leafs sold are high-trim models, they note. But those have been snapped up by early adopters, who have been eager for bells and whistles and have the disposable income to pay for them.
As the Leaf rollout continues and electric cars lose their nichelike novelty, however, Nissan expects shoppers may be more price conscious.
Lindsay Chappell contributed to this report