Well, chalk up another first for Nissan: It sold 3,117 Leaf electric cars in the U.S. last month.

That's not only its best-ever one-month sales performance, but it's the first time any carmaker has sold more than 3,000 battery plug-in electric cars in a month in this country--ever. (August 2013 sales for the range-extended Chevy Volt were 3,531.)

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2014 Chevrolet Volt

2014 Chevrolet Volt

The May result brings total year-to-date Leaf sales to 10,389, and increases the Leaf's U.S. sales lead among all plug-in cars for 2014.

It also takes total Leaf sales in the U.S. above 50,000--to 52,511, precisely--though the Leaf is still in second place for total sales since December 2010 to the Chevy Volt range-extended electric car.

Meanwhile, the Volt delivered 1,684 units last month, bringing its 2014 total to date to 6,838. That's only marginally up on the 1,607 Volts delivered in May a year ago.

A total of 61,390 Volts have been sold in the U.S. in the 42 months starting with the first delivery in December 2010, just three days after the first Leaf was delivered.

The Volt has sold at roughly these levels for about two years, almost in an extended glide path to the anticipated start of production of an updated 2016 Volt a year or so from now.

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2014 BMW i3 REx range-extended electric car owned by Tom Moloughney - after delivery

2014 BMW i3 REx range-extended electric car owned by Tom Moloughney - after delivery

New entrant from BMW

A new electric car joined the sales roster in May: BMW delivered 336 of its new and radical i3 battery-electric car in May. It's a  seemingly strong start given that the first battery-electric model was delivered May 3, but range-extended models didn't start delivery until almost three weeks later.

The company didn't immediately specify how many of them were fitted with the optional REx range-extending two-cylinder engine

And as always, it's not known how many Tesla Model S electric luxury sedans were delivered last month, because Tesla refuses to report monthly sales figures.

We surmise that it delivered perhaps 1,200 cars in the U.S. as it continues to divert production to markets in Europe and China.

Plug-in hybrids

Beyond the big three--Leaf, Volt, and Model S--are three plug-in hybrid models.

The Toyota Prius Plug-In Hybrid sold a whopping 2,692 units in May. That's its best monthly total ever, and brings the 2014 total to 7,729--meaning it's sold in higher volumes this year than the Chevrolet Volt has.

Ford sold 782 C-Max Energi hatchbacks and a record-breaking 1,342 Fusion Energi sedans, bringing total sales for its plug-in hybrids to 2,940 and 4,296 respectively.

Two lower-volume vehicles round out the category. May sales of the Honda Accord Plug-In Hybrid were 46, bringing the year's total to 152, and total sales since January 2013 to 678.

Deliveries for Porsche in May were 53 plug-in Panameras, for a year-to-date total of 370 (plus 45 more in December)--meaning the Porsche plug-in hybrid continues to outsell the Cadillac ELR by about 50 percent.

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Low-volume and compliance cars

The last and largest group of plug-in electric models to record sales in May are the compliance cars and those whose sales volume is no more than compliance level.

The Smart Electric Drive set a new record of 206 cars sold during May, bringing the smallest electric car's year-to-date total to 814 and total deliveries since last May to 1,737.

Now that its 2014 i-MiEV electric minicar has finally gone on sale, Mitsubishi sold 35 of its electric minicar--the highest monthly number since last May and almost half of its year-to-date sales of 75. We expect next month's i-MiEV total to be higher yet.

May sales of the Ford Focus Electric were 177, bringing this year's total to 699, while GM delivered 52 Cadillac ELR coupes in May, bringing the total sold since December last year to 299.

Of the compliance cars, the Chevrolet Spark EV logged its best month by far since it went on sale last June, with 182 sales in May--bringing its 2014 total to 369 and total deliveries to 908.

Honda Fit EV sales were 33, bringing the year's total to 183, and the total since July 2012 to 845. And Toyota sold 149 RAV4 EVs--its best month since last September--bringing its year-to-date total to 455.

As for the Fiat 500e, Chrysler refuses to supply sales data.


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