New cars and trucks are selling at a blistering pace in the U.S. right now, adding to a seventh consecutive year of volume growth for the industry.

But with half the year gone, sales of plug-in electric cars are in something of a holding pattern despite a surge last month, pending the launch of two key products.

Those are the 2016 Chevy Volt plug-in hybrid, with its 50-mile electric range and gasoline engine, and an updated 2016 Nissan Leaf thought to have a range of 100-plus miles.

Until those cars arrive in volume on dealer lots, plug-in sales are growing--but not as much as they have in recent years.

DON'T MISS: May's Plug-In Electric Car Sales: Leaf, Volt, Others Surged

For June, 2,074 Nissan Leafs were delivered to buyers--bringing the half-year total to 9,816 , compared to 12,736 during the same period in 2014.

Total U.S. Leaf sales are now 82,138, increasing its lead over the outgoing Chevy Volt--and adding to its position as the best-selling electric car in history.

Last week, in fact, Nissan and its partner Renault delivered their quarter-millionth electric car. More than 180,000 of that total were Nissan Leafs.

2016 Chevrolet Volt plug-in hybrid - details of Voltec drivetrain from SAE presentations, Feb 2015

2016 Chevrolet Volt plug-in hybrid - details of Voltec drivetrain from SAE presentations, Feb 2015

The Chevrolet Volt, meanwhile, saw 1,225 sales in June--its second-highest month this year--for a six-month total of 5,662. Total U.S. Volt deliveries are now 78,979.

The 2016 Volt is now in pre-production at GM's Detroit-Hamtramck assembly plant, and we expect it will start showing up at dealers in California sometime during September.

Supplies for the rest of the country will follow during the rest of the autumn.

ALSO SEE: Will 2015 Plug-In Electric Car Sales Exceed Last Year's Total?

As always, Tesla Motors refuses to release monthly sales figures--or indeed sales by country--for its Model S luxury electric car.

The company did promise last quarter to release total global sales for the quarter within a few days after the quarter closes, so we look forward to that piece of data in the next few days.

2013 Tesla Model S and 2014 BMW i3, Hudson Valley, NY, Nov 2014

2013 Tesla Model S and 2014 BMW i3, Hudson Valley, NY, Nov 2014

The remaining high-volume plug-in vehicle is the BMW i3, which in battery-electric and range-extended versions combined has exceeded 1,000 units a month several times over the last year.

In June, however, just 551 units were delivered, possibly due to rumored supply shortages owing to demand in other global markets.

MORE: Why Electric Cars Are Rare Outside CA: Arcane 'Travel Provision' Rule

For the first six months of 2015, a total of 4,456 i3s have found buyers in the U.S. market--making the little carbon-fiber-reinforced plastic electric minicar either the third- or fourth-best-selling plug-in car in the country just 14 months after it launched.

Plug-in hybrids

As for the higher-volume plug-in hybrid models, the plug-in Toyota Prius racked up 464 sales, about average for the six-month period that saw a total of 2,890 delivered.

That compares to 9,300 during the same first half last year, and reflects both the waning of the model and an end to the supply of green stickers for single-occupant carpool-lane access in its stronghold California market.

The Toyota Prius Plug-In Hybrid ended production last month; a new model will lag this autumn's launch of the all-new 2016 Prius hybrid model by at least several months.

2012 Toyota Prius Plug-In Hybrid, production version road test, San Diego, CA, Jan 2012

2012 Toyota Prius Plug-In Hybrid, production version road test, San Diego, CA, Jan 2012

Each of Ford's two plug-in hybrid models beat that Prius in June sales. The Fusion Energi mid-size sedan had 727 deliveries, and the C-Max Energi compact tall hatchback had 667--both of which were lower than May's numbers.

Total year-to-date sales of the three highest-selling plug-in hybrids are 4,290 for the Fusion Energi, 3,543 for the C-Max Energi, and 2,890 for the Prius Plug-In Hybrid. That's a sharp reversal of the same period last year, where the plug-in Prius outsold both of Ford's Energi models.

The Honda Accord Plug-In Hybrid, always a limited and low-volume contender, sold four units in June, for a six-month total of only 59. It will be withdrawn from the market after this year.

Low-volume cars

Finally, as always, we're aggregating data for the many lower-volume vehicles--with sales of, say, 300 or less a month--that make up the majority of the two dozen plug-in electric vehicles offered for sale in (parts of) the U.S.

2016 Cadillac ELR

2016 Cadillac ELR

Just 62 Cadillac ELR range-extended electric sport coupes were delivered in June, its lowest monthly total since May 2014. The ELR's half-year total is 593 sold to date.

In that same price range, Porsche's pair of plug-in hybrid luxury sports models saw sales of 88 for the Cayenne SUV and 34 for the Panamera large sedan. The first-half totals for the two cars were 486 and 230, respectively.

At a higher price than any of the above (base price: $135,000) were the 137 gull-winged BMW i8 plug-in hybrid sport coupes, for a six-month total of 733 (and total deliveries since going on sale last August of 1,288.

At more achievable prices, 293 Volkswagen e-Golfs were sold in June, bringing the half-year total to 1,518. An additional 357 were sold in November and December last year.)

2014 Mercedes-Benz B-Class Electric Drive - First Drive, May 2014

2014 Mercedes-Benz B-Class Electric Drive - First Drive, May 2014

The other German compact five-door hatchback, the Mercedes-Benz B-Class Electric Drive, saw sales of 242 for a six-month total of 1,172.

Its half-brother under the Daimler family tree, the Smart Electric Drive, saw 94 deliveries, for a half-year total of 646.

And the lowest-volume battery-electric car in the land, the Mitsubishi i-MiEV minicar, racked up 23 more sales, bringing its six-month total to 72 cars.

That also brings its total since 2011 to within a hair's breadth of 2,000, which it should cross in July or August.

Compliance cars

As for compliance cars--or those sold under circumstances that make them look a whole lot like compliance cars--the Chevrolet Spark EV saw 264 sales, the second month at that level after its record-breaking total of 920 in April.

Thus far, Chevrolet has delivered 1,823 battery-electric Sparks, making it by far the highest-volume compliance car this year.

The GM brand said that demand exists for more Spark EVs, but that it wasn't sure it could get enough cars from the factory in South Korea to satisfy all customers.

2014 Chevrolet Spark EV - First Drive, Portland, July 2013

2014 Chevrolet Spark EV - First Drive, Portland, July 2013

Ford sold 152 Focus Electric hatchbacks in June, its second-best month thus far this year, for a six-month total of 811--pretty much on pace with last year, and the year before.

No Honda Fit EVs or Toyota RAV4 EVs were delivered in June, and both models have now been discontinued after meeting their compliance goals under California's zero-emission vehicle regulations.

Fiat refuses to break out sales of its 500e battery-electric minicar; Kia gives the same blanket refusal for its Soul EV electric tall wagon.


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