There have always been people willing to be the big-spenders on flashy or cutting-edge cars (think of Arnold Schwarzenegger's unfortunate embrace of the Humvee, or anyone who's ever bought a Lamborghini), but the bulk of the auto market is now, and will always be, made up of very run-of-the-mill vehicles.

Electric vehicles are still largely in the former category, although the Nissan Leaf and Chevy Volt are starting to change that. And a recent sustainability conference at Infineon Raceway brought together some of the biggest players in EV technology to talk about how to overcome the challenges to making EVs mass-market vehicles.

Executives from four firms that are heavily invested in EVs and technology supporting them -- Tesla, Panasonic, Infineon Technologies and Kleiner Perkins Caufield & Byers -- provided a frank look at the state of the EV industry during the conference last week. They also delved into what it will take to make plug-in EVs live up to their promise. Sales of plug-in cars, from hybrids to battery electric vehicles, are expected to grow from 114,000 cars today to 5.2 million units worldwide by 2017. EVs, the energy that powers them and the technology that can connect them are key components of the concept GreenBiz Group calls VERGE.

To make inroads among mass market consumers, speakers said, EV makers and supporting industries must:

1. Make plug-in electric vehicles that fit in.
2. Tackle range anxiety and charging challenges.
3. Invest strategically in innovation and sustainability.

Here are key points from the talks:

1. Fitting In

Faddish and costly EVs, like Muammar Qaffidi's customized Fiat 500, and trippy-looking bargain models, like the recently introduced Renault Twizy, make great headlines and photo ops.

But if you want lots of regular folks in the U.S. to buy EVs, they need to look like regular cars, be cost competitive, and perform as well as if not better than standard vehicles -- in addition to offering environmental benefits of reduced air and noise pollution, greenhouse gas emissions and reliance on fossil fuels.

"People are not going to gravitate to anything new until it makes economic sense," said Joseph Hustein, associate director of the Revs Program at Stanford University, speaking about the tipping point for sustainable auto technology in the mass market.

The average consumer also won't buy anything that looks radically different, at least not yet, marketing experts pointed out.

2. Tackling Range Anxiety and Charging Challenges

The big fears about plug-ins include running out of juice, not finding a charging station on the road, forgetting to recharge entirely, and burning time to power up. The panel focused on EVs spent much of its discussion acknowledging the worries and trying to dispel them.

"I can image you coming home from work with a bag of groceries, screaming kids and a barking dog, and forgetting to plug your car in, and the next morning you don't have a way to get to work," said Mark Bellinger, a vice president for Infineon Technologies, North America.

While there isn't a sure way to remedy forgetfulness, range and charging availability aren't the bogeys they've been made out to be, some speakers said.

"We don't make that big an issue of charging," said Ryan Popple of the Greentech Team at Kleiner Perkins Caufield & Byers. "In a lot of ways, I think it has become a red herring."

Range and Charging Availability

Plug-in hybrid electric passenger vehicles, like conventional electric hybrids before them, are expected to ease the way for plug-ins of all types. The hybrids -- despite their drawbacks of added weight from dual propulsion systems, battery packs and fuel when compared to pure EVs -- are likely to dominate plug-in sales until more people get comfortable with the concept.

Also expect to see "over-spec'd EVs with really big [battery] packs as safety blankets," said Popple. That will change as more people become accustomed to plug-ins, and eventually charging a car won't pose any more anxiety than charging a phone, he said.

Many EV buyers are pleasantly surprised to find the available range is pretty much in line with their needs, said Tom vonReichbauer, finance director of Tesla Motors, the maker of luxury, 100 percent electric cars. Tesla, however, was the first company to put a 200-mile-range EV on the road. In 2012, it will offer a 300-mile electric car (about the range of a standard gas tank) and the company's Model S will give buyers a choice to pick a battery size that suits them.

EV drivers also are finding it's easier to charge up away from home than they imagined, vonReichbauer said. Cities, hotels and companies are installing charging stations, but there are already "tons of places" to charge, he said. "You can go to hotels, ask the guy at the front counter where you can have access to a 240-volt outlet, and they'll point you to it."