(McClatchy/Tribune illustration)

Those electric vehicles popping up in driveways look a lot like their gas-powered cousins. But under the hood, they're different machines, and their potential problems are foreign to many drivers and mechanics alike.

Any suggestion that they might be more dangerous — true or not — could stop sales cold, analysts say. That's why the industry shuddered last month when the National Highway Traffic Safety Administration opened an investigation into the Chevrolet Volt's lithium-ion battery pack.

NHTSA said two Volt batteries caught fire after crash simulations — one three weeks after the crash, the other a week later.

A nationwide survey by Bandon, Ore.-based CNW Research showed a sharp decline in consumer consideration of the Volt in the aftermath of the NHTSA investigation, even though Transportation Secretary Ray LaHood said the Volt is safe to drive.

General Motors took the unusual step of offering free loaner cars to concerned Volt owners during the probe. It was characterized as a goodwill gesture, not an admission of safety concerns. GM says it has had few takers.

GM insists that the Volt — which the automaker spent years and millions of dollars developing — is solid, wave-of-the-future technology, not unlike early internal combustion engine-powered cars that went through some growing pains.

"This technology should inspire confidence and pride, not raise any concern or doubt," said Mark Reuss, president of GM North America.

Auto industry analysts say the attention given the Volt — which can be charged via a plug in a standard electrical outlet, then driven longer distances with a gas engine replenishing the battery — is indicative of the high stakes in the evolving electric vehicle, or EV, industry.

Billions of development dollars are on the line, not to mention the jobs that go with building and servicing EV systems.

Jesse Toprak, an analyst for TrueCar.com, noted that GM took a long time to bring the Volt to market, working to perfect the complex battery, a primary source of heat generation. He said perception sometimes trumps reality in new technology, and the spotlight on the Volt could upset future GM plans.

If GM "can replicate the (Volt) technology into different categories of vehicles, including SUVs and trucks, that will be a game-changer," he said.

Dave Barthmuss, a GM spokesman who specializes in California environment/energy issues, believes the public ultimately will sort out and understand EV technology, just as it did for decades with gas-fueled cars.

"It is evolving," he said. "You can have a gasoline vehicle that can pose just as many challenges if faced with the right circumstances. The Volt is safe. I wouldn't hesitate to put my children in it.

"Because (EVs) are an evolving technology, we have to be as responsive as we can be to all problems and public concerns," Barthmuss said. "Public education is a process that's likely going to take multiple years."

A generation ago, onboard battery packs were not on consumers' radar. That began to change in 2000, with the introduction of the Toyota Prius gas-electric hybrid sedan.

Now, a host of hybrids are on the U.S. market. The next wave in the evolutionary process is all-electric drive systems.

Current electric models include the Nissan Leaf, a five-door hatchback that can go about 100 miles per charge; the Tesla Roadster, a high-performance luxury electric convertible; and the Fisker Karma, a plug-in hybrid capable of 125 miles per hour.

More electric vehicles are in the pipeline as public and government pressure grows to ease foreign oil dependence, decrease household gasoline bills and reduce greenhouse gas emissions.

Rising EV numbers have created challenges in the vehicle repair/service industry.