The failure of electric vehicles to gain steam among consumers continues to vex automakers.

The conventional wisdom is that EVs are too expensive compared to internal-combustion engine vehicles — and that’s true. But there are other nuances hampering sales.

Electric cars and plug-in hybrid vehicles will account for only 2.4% of U.S. auto sales by 2023, according to a new Navigant Research report.

Here’s an assessment of why the industry’s key electric vehicles aren’t taking off among consumers:

■ Chevrolet Volt: The semi-electric car manufactured by General Motors hit dealerships in late 2010, but sales remain tepid. Despite a price cut to $35,000 and aggressive lease deals at times, consumers haven’t flocked to the car. GM CEO Mary Barra acknowledged the company has done a poor job of educating people about the vehicle. It uses a lithium-ion battery pack to get up to 38 miles of range on electricity, then a gasoline engine kicks in. GM plans to introduce a redesigned Volt at the Detroit auto show in January, so expect better range, improved design and possibly a lower price.

■ Tesla Model S: Billed as the industry’s most successful car, its secret to success is that it appeals to ultra-luxury car buyers, offering an excellent ride quality, design and materials. At prices that often top $100,000, no one is buying the Model S to save money on gasoline. Barclays recently projected Tesla would deliver 7,800 vehicles worldwide in the third quarter — impressive for an upstart automaker many believed would never succeed. But Bank of America analyst John Murphy said earlier this year that Tesla’s market share in the U.S. over the next several years will be negligible.

■ Nissan Leaf: The pure-electric car has failed to meet the company’s ambitious targets — and the key reason is lack of range. It gets 84 miles on a single charge of electricity. That’s plenty for city driving, but it completely rules out long trips because of a fundamental lack of charging infrastructure. Until the range increases significantly, the Leaf’s prospects are probably limited.

■ Toyota Prius Plug-in: This version of the popular Prius can only drive 11 miles on a single charge of electricity before it starts using gasoline. Sales have been halting. In September, sales totaled a measly 353 units in the U.S., according to GreenCarReports.com. Why buy a Prius plug-in when the Prius hybrid is so dependable?

■ Ford plug-in vehicles: The Energi plug-in, Fusion plug-in and Focus electric have not assembled a significant audience, perhaps in part because it’s hard to distinguish them on the road from their more traditional counterparts.

■ Cadillac ELR: GM’s most expensive base-price vehicle, the ELR can start at more than $80,000. GM sold 111 in September — and you can blame the high price tag for its problems. It’s effectively a luxury version of the Volt at twice the cost.

Contact Nathan Bomey: 313-223-4743 or nbomey@freepress.com. Follow him on Twitter @NathanBomey.