After the usual winter doldrums at the start of the year, April proved to be a good month for plug-in electric car sales in the U.S.

March was a record-breaking month, and as April results come in today and tomorrow, last month's pace seems to be robust as well.

As usual, the two highest-volume cars for which we have reported data are the Chevrolet Volt plug-in hybrid and the Nissan Leaf battery-electric hatchback.

DON'T MISS: Plug-In Electric Car Sales For 2015 Fall Slightly From 2014

The Volt, which was entirely redesigned as a 2016 model but sold only in certain regions, is now becoming available across the country as a 2017 car.

Its deliveries last month were 1,983, on top of 1,865 in March, bringing its four-month total this year to 5,940—its highest ever for the period, besting totals over 5,000 in 2012 and 2013.

At this pace, the total number of Volts delivered will cross the 100,000 mark sometime this summer, a notable achievement.

2016 Nissan Leaf SL, Hudson Valley, NY, Dec 2015

2016 Nissan Leaf SL, Hudson Valley, NY, Dec 2015

The Nissan Leaf, meanwhile, got a range boost for 2016, from an EPA-rated 84 miles combined to 107 miles from a larger 30-kilowatt-hour battery pack in the SL and SV models.

April sales for the Leaf were 787, over a March number that at least cracked the four-figure mark, at 1,246.

But with longer-range Leafs now rolling into dealers after a production start late in 2015, its four-month total of 3,718 is far from its best ever—that was 7,272 back in 2013.

ALSO SEE: 2017 BMW i3: up to 114 miles of range from 50-percent battery increase

As always, Tesla Motors refuses to break out its sales of Model S and Model X luxury electric cars by month or region, so we don't have comparable numbers for the longest-range plug-in vehicles sold in the U.S.

Other high-volume entries include the BMW i3, whose April sales soared to 814, its best number since last December.

The previous few months had been much lower, as the company prepared to roll out a longer-range 2017 version—but the number may reflect some clearance pricing on the 81-mile 2016 models.

2016 Ford Fusion Energi

2016 Ford Fusion Energi

Ford's pair of Energi plug-in hybrids, the C-Max compact hatchback and Fusion midsize sedan, logged sales of 607 and 1,331 respectively for April.

Their four-month totals are now 2,057 and 4,082, as the smaller C-Max continues to wane against the larger Fusion, which is likely seeing increased fleet sales.

The Volkswagen e-Golf, whose sales grew substantially during the end of 2015, has fallen back to much lower numbers, though April deliveries of 326 returned it to the January level and closer to its overall monthly average.

Thus far, Volkswagen has sold more than 5,500 e-Golfs in the U.S. since late 2014.

But the 83-mile electric car will need a range boost soon if it is to keep up with the growing array of 2017 models rated at more than 100 miles.

2016 Audi A3 e-Tron Sportback, San Francisco Bay Area, Oct 2015

2016 Audi A3 e-Tron Sportback, San Francisco Bay Area, Oct 2015

The Audi A3 e-tron remains the impressive vehicle in the group of high-volume vehicles, with April sales of 321 bringing its year-to-date total to 1,228.

That's a substantial number for a car that's only been on sale four months (and one day).

Some makers, including Audi, BMW, and Volvo, have a significantly higher percentage of plug-in sales overall—despite the higher absolute numbers of cars sold by the largest makers like General Motors and Nissan.

Beyond those few high-volume vehicles are the growing number of mid-size to luxury plug-in hybrid sedans and SUVs, all of which sell in relatively low absolute numbers.

Pricier plug-in hybrids

The Cadillac ELR range-extended luxury coupe sold 95 units, bringing its 2016 total to 357 and its lifetime sales to a mere 2,697.

BMW i8 Protonic Red Special Edition, 2016 Geneva Motor Show

BMW i8 Protonic Red Special Edition, 2016 Geneva Motor Show

BMW sold another 237 i8 plug-in hybrid gullwing sport coupes, attesting to that $140,000-plus vehicle's continuing popularity and stunning looks. Its year-to-date total is 799.

Porsche's pair of luxury plug-in hybrids, the Cayenne SUV and Panamera sedan, came in at 237 and 25 last month, for four-month totals of 799 and 108 respectively.

The Cayenne S E-Hybrid has been strong lately, and is now part of a segment that includes plug-in hybrid SUVs from BMW, Volvo, and soon Mercedes-Benz.

We'll add numbers a bit later for the three remaining cars on our list: the BMW X5 xDrive 40e, Hyundai Sonata Plug-In Hybrid, and Volvo XC90 T8 Twin Engine.

 

2016 Smart Fortwo Electric Drive

2016 Smart Fortwo Electric Drive

Low-volume entries

Finally, the more than two dozen plug-in electric cars on sale in the U.S. are rounded out by the handful of compliance-car and low-volume battery-electric entries.

The hapless Mitsubishi i-MiEV added another 6 sales in April, bringing its year-to-date total to 14, and total deliveries over more than four years to 2,022.

The Smart Electric Drive (which will be replaced with an entirely new model within the year) sold 66 in April, for a four-month total of 238.

Few people realize that there have been more than 5,000 electric Smarts sold since 2013, or roughly one in five Smart cars of any kind delivered in the U.S.

2015 Mercedes-Benz B-Class [Canadian-spec]

2015 Mercedes-Benz B-Class [Canadian-spec]

Its big brother Mercedes-Benz shifted 56 more B-Class Electric Drive models, bringing the 2016 total to 217.

That's roughly on par with the electric Smart, which has only half as many seats but costs only half as much.

Compliance cars

As for the compliance cars, the Chevy Spark EV soared to 419 deliveries, giving 1,026 for the year to date.

CHECK OUT: Is Chevy Bolt EV's Main Mission To Marginalize Tesla Electric Cars?

Its sales have settled in at higher levels than they reached when it was introduced, as Chevrolet counts down to the launch late this year of its 200-mile 2017 Chevrolet Bolt EV.

The Ford Focus Electric saw April sales of 81, bringing the 2016 total thus far to 338.

No data is available for the Fiat 500e and Kia Soul EV, whose makers refuse to break out sales.

Finally, another 41 Toyota Mirai hydrogen fuel-cell vehicles were delivered in April, bringing 2016 sales to 138. A total of 210 Mirais have been delivered since last October.

_______________________________________

Follow GreenCarReports on Facebook and Twitter.