More Nissan Leaf electric cars were sold in 2014 than in any model year before or since, fully 30,000 of them.

That means a whole lot of three-year leases are coming due this year.

Now Nissan is offering to extend those leases—and in the process, it's given us a little more information on the upcoming 2018 Nissan Leaf.

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That second-generation Leaf, one version of which is expected to offer a range of 200 miles or more, will make its world debut this September.

That's the word from Nissan in the first of two tweets this morning.

The second tweet says the company will extend the leases for "many owners" (those whose leases expire this year) and give them three months of courtesy payments into the bargain.

Perhaps best of all, those owners will get a spot on the waiting list for the new 2018 Leaf.

That car, according to Nissan sources, will go on sale before the end of the year. It is expected to have similar design elements to the 2015 Nissan Sway concept car. 

The company says that more details on the 2018 Nissan Leaf will be released "in coming months."

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Meanwhile, though, it's clearly concerned about hanging onto its existing lessees, who are almost surely the most likely to buy a new Leaf.

UPDATE: We were able to chat with Brian Maragno, Nissan North America's director of electric-vehicle marketing and sales strategy, who provided more details, as follows.

The offer applies to any Leaf lessee whose lease expires on April 1 or later, both original lessees and those who have extended their leases one or more times.

For details, lessees should contact Nissan's EV call center at 855-467-3214.

Nissan Sway Concept - 2015 Geneva Motor Show live photos

Nissan Sway Concept - 2015 Geneva Motor Show live photos

Maragno said those whose leases are through the Nissan Motors Acceptance Corporation can also contact NMAC's call center for the same information.

The details of the 2018 Leaf pre-order list are still being finalized, he said, so he couldn't specify the priority rankings of those who sign up via the lease-extension program.

It will also be opened to current Leaf owners, those who have purchased their cars outright—whether new or as Certified Pre-Owned cars at the end of their leases.

In general, he said, priorities will vary depending on where the buyer is located, the model and features ordered, and a few other factors.

Those details will become available once the 2018 Leaf is unveiled in September and final pricing and features are released after that.

Maragno stressed that customers who extend their leases won't find that Nissan simply signs a new lease and then vanishes.

Section of 2018 Nissan Leaf spy shot [image via S. Baldauf/SB-Medien, as used on Motor Authority]

Section of 2018 Nissan Leaf spy shot [image via S. Baldauf/SB-Medien, as used on Motor Authority]

They'll receive periodic communications about the new Leaf, with more information as it's released, both before and after the 2018 Leaf's official global debut.

"We think the all-new Leaf will exceed expectations," he suggested, "in range, technology, design, and value."

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