When the final figures for 2013 are tabulated, sales of battery-electric and plug-in vehicles in the United States are expected to nearly double 2012’s totals, according to the Electric Drive Transportation Association (EDTA), a trade group based in Washington, D.C. Even so, that is fewer than 100,000 vehicles, in a year when the industry is on track to comfortably top 15 million sales.

There is no denying that cars with plugs are finding more buyers, a positive development in the eyes of environmentalists. Still, the high points of 2013 were sometimes offset by setbacks. For instance, tepid sales of several EV models, as well as the Chevrolet Volt plug-in hybrid, had automakers slashing prices by thousands of dollars.

At the same time, a segment star, the Tesla Model S, proved it could hold its own in the premium market, projecting sales of about 20,000 cars in the United States. The electric Tesla has been a headline-maker, outselling some gas-powered competitors. In October, Edmunds.com reported that the Model S was the “most registered” new vehicle in eight of America’s 25 wealthiest ZIP codes.

The good news was tempered, though, by reports that three Model S sedans caught fire, two after hitting objects in the road, one after a crash. In November, the National Highway Traffic Safety Administration (NHTSA) said it would open an investigation.

For most of the industry, the year was quieter. Some of the plug-in cars introduced in 2013 — from major automakers including BMW (arriving here in the spring), Chevrolet, Fiat, Ford, Honda and Porsche — were offered only in limited markets, always including California.

Consumers now have 16 plug-in models to choose from, the association said. Yet sales seemed to hit a plateau, with the Volt and the Nissan Leaf battery car each stabilizing at about 2,000 a month. Ford’s two plug-in hybrid Energi models together make similar numbers, and the plug-in Toyota Prius around 1,000.

“I think it was a good year,” Brian Wynne, president of the association, said in a telephone interview, citing the rapid expansion of public charging stations as a hopeful sign. According to the Energy Department, there were 6,712 such stations in the United States in mid-December.

Eric Evarts, senior associate autos editor at Consumer Reports, said in an email that 2013 was the year electric vehicles “really captured the public imagination” and became “more practical for the mainstream.”

A survey released this month by Consumers Union and the Union of Concerned Scientists said that some 42 percent of respondents would find a plug-in hybrid to be a good fit for their needs. Is it significant that Mary Barra, who will take over as chief executive of GM next month, was trained as an electrical engineer?

In an interview before her appointment was announced, she said GM was “very committed to electrification.” And in a development that could mean greater support for green cars at the federal level — at least temporarily — David Friedman, a former leader of the clean-vehicles program at the Union of Concerned Scientists, will serve as acting administrator of NHTSA following the departure of David Strickland.

With growing availability, sales of conventional hybrids continue to climb. Americans have bought more than 3 million hybrids since they arrived in 1999, and they are holding steady at around 3 percent of total vehicle sales.

Still, cheaper alternatives to hybrids and battery cars advanced in 2013. Diesels and small gasoline engines, often turbocharged, are gaining ground, with offerings like Ford’s 1-liter three-cylinder Fiesta delivering 45 mpg on the highway when equipped with a manual shift.