An obvious digital rendering shows the revised rear of the Detroit Electric SP:01 sports car's "final design."

Better late than never? That’s apparently the philosophy at Detroit Electric, the ambitious, if struggling, battery-carmaker that has been promising to put the world’s fastest electric sports car into production.

First teased at a splashy Motown event in the spring of 2013 – with a concept vehicle unveiled at last year’s Shanghai Motor Show, Detroit Electric has missed all of its original targets. But despite the legions of skeptics, it has today released an image of what it is billing “the final exterior design” of its pure battery electric sports-car, the SP:01.

Apparently, quite a bit has changed since Detroit Electric first announced plans to revive a brand name that has been gone since the Great Depression.

“The final design of SP:01 incorporates signature Detroit Electric design DNA, carried over from the prototype model we revealed last year,” says Jerry Chung, Detroit Electric’s design director. “Coupled with many motorsport visual cues, the new fastback design, bold face and sharp contours evoke the company’s vision of pure electric performance.”

CEO Albert Lam shown pulling the covers off the Detroit Electric SP:01 concept in Detroit last year.

From a styling standpoint, the teaser image shown here reveals that the two-seat sports car will no longer use the flying buttress design of the original SP:01 concept. The “final” version adopts a more contemporary fastback shape which, Detroit Electric claims, was “optimized using computational fluid dynamics analysis” to improve aerodynamics for maximum performance and stability.

What we can’t see are the front-end “aesthetic and functional enhancements, such as the reshaped air intake and outlet ducts on the hood.

Meanwhile, it appears Detroit Electric took a tip from electric vehicle rival Tesla Motors – which suffered some embarrassing battery fires and had to redesign its pack to prevent damage from road debris. The SP:01 pack now is wrapped in a composite casing that has the added advantage of improving the sport car’s torsional rigidity, the company claims.

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Another key change involves the production of the little SP:01. When former Lotus Engineering Group CEO Albert Lam announced the project last year, the goal was to set up a small plant in the Motor City suburbs to assemble the sports car – which was to be based on a Lotus platform. At the time, few expected the company to meet its target of launching production before the end of 2013, if ever.

Detroit Electric now says it will go into production at a “new facility” in the U.S. by the end of this year. Specific details have yet to be revealed.

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Also left to be discussed, the start-up carmaker’s longer-term plans. The original goal was to use the SP:01 as a limited-production halo car that would help re-launch the Detroit Electric brand name. As it appears the revised plans still envision limited production, the maker may be sticking with the basic of its long-term business model.

What hasn’t changed is Detroit Electric’s claims that the SP:01 will be “the world’s fastest production electric sports car” when it reaches showrooms in North America, Europe and Asia next year. The maker promises a 0 to 60 launch time of 3.7 seconds, with a 155 mph top speed.

That claim may need an asterisk. Tesla recently announced a new all-wheel-drive version of its Model S, including a high-performance version that CEO Elon Musk claims will deliver McLaren-like acceleration – which would mean something in the low 3-second range for a launch. But the Model S is a sedan, so Detroit Electric’s boast might be true, albeit with a more narrow interpretation than when the SP:01 was first revealed last year.

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