Sales of four high-volume plug-in electric cars rose last month, with new monthly record for the Chevy Bolt EV and the Toyota Prius Prime.

The 2017 Chevrolet Bolt EV 238-mile battery-electric hatchback logged its highest monthly total since sales began in December.

Chevrolet delivered 1,566 Bolt EVs, bringing this year's five-month total to 5,950 (another 579 were sold in December 2016).

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The Bolt EV is continuing a lengthy rollout across the states of the U.S., with cars not planned for delivery in the final states (including GM's home state of Michigan) until September.

This marks the third of six months that the Bolt has outsold the Nissan Leaf, which saw sales of 1,392 in May, bringing its five-month total to 5,741.

That Leaf sales rate is higher than the comparable rate for 2016, when 4,692 were sold through May.

2017 Nissan Leaf

2017 Nissan Leaf

The third car, the Chevrolet Volt plug-in hybrid, had the highest sales of the three: 1,812 Volts were delivered, bringing its total through May to 9,187.

All three of those cars, however, were outsold by the Toyota Prius Prime plug-in hybrid, which logged 1,908 deliveries last month.

That brings its five-month total so far this year to 8,073—lower than the Volt's 9,187 but higher than the totals for the Bolt EV and the Leaf.

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As usual, Tesla refuses to release monthly sales data or to break down its quarterly sales by country.

That means comparable data for its Model S and Model X deliveries isn't available, and this site chooses not to use data from other sources that's not directly comparable.

Ford had a relatively good May: deliveries of its C-Max and Fusion plug-in hybrid Energi versions were 950 and 1,000, higher than in recent months, bringing their year-to-date totals to 3,444 and 4,350—lower than those of the top four cars.

2017 BMW i3

2017 BMW i3

Among the medium-volume entries, 506 BMW i3 and 381 Volkswagen e-Golf compact electric hatchbacks were sold.

That brings the five-month total for each car to 2,425 and 1,655 respectively.

The similarly sized Mercedes-Benz B250e saw deliveries of just 46 units, for a year-to-date total of 271 battery-electric cars.

READ THIS: When can I buy a Chevy Bolt EV electric car? State-by-state schedule

On the plug-in hybrid SUV front, 174 pricey Porsche Cayenne S e-Hybrids found buyers in May, for a five-month total of 783 so far.

Volvo delivered 176 of its XC90 T8 "Twin Engine" plug-in hybrid luxury SUV, bringing the 2017 total to date to 573.

One final note from GM delivery data: for the second month this year, no Cadillac ELR range-extended luxury coupes were sold.

2016 Cadillac ELR

2016 Cadillac ELR

(Also, no Chevrolet Spark EV electric minicars were sold for the first time this year.)

Total 2017 sales of the ELR so far this year have been just 7, meaning the lifetime sales of that car—based on the first-generation Volt and launched at the startling price of $75,000—are fewer than 3,000 units.

The Ford Focus Electric, which finally got a higher-capacity battery this year, saw sales of 132, bringing its yearly total to 948.

In addition to Tesla, the manufacturers that refuse to release breakdowns of the plug-in versions of conventional models include BMW, Chrysler, Fiat, Hyundai, and Kia.

EDITOR'S NOTE: Starting this month, this report will only cover plug-in electric cars with sales of 100 units a month or more—with occasional exceptions for new models, exceptionally large changes, or other newsworthy events.


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