DETROIT -- Elon Musk predicted two years ago that a Tesla should be able to travel almost 746 miles on a single charge by 2020.
It was considered a bold statement from a CEO known for making bold statements, but it was also a sentiment that reflected a widely held belief in the inevitability of, and need for, increasingly longer-range electric vehicles if the vehicles were ever to truly gain traction with consumers.
Electric vehicle battery technology has improved since that 2015 prediction and some vehicles continue to push the limits for range -- some versions of Tesla's Model S luxury sedan already rate at more than 330 miles on a charge under normal conditions, and an Italian Tesla owners group said in August that it managed 670 miles driving with no air-conditioning at 25 mph.
But recent assessments by industry watchers and auto executives are tapping the brakes on the idea that the foreseeable future of mainstream electric vehicles will be tied to an ever-expanding range.
Some experts now say they believe the sweet spot for battery range might already have been reached.
"I wouldn't expect to see vehicles go much beyond about 300 miles per range and I think most mainstream EVs are probably going to be in the, kind of where the Bolt is now, 200 to 240 miles of range, and I think the 200-mile threshold is really kind of the sweet spot for EV," said Sam Abuelsamid, a senior analyst at Navigant Research who is based in the Detroit area.
The idea will get tested as an increasing number of automakers roll out new electric vehicles in coming years.
Ford and General Motors, for instance, made major EV (shorthand for electric vehicles) announcements in recent weeks, with Ford saying it would invest $4.5 billion and introduce 13 new electric vehicles in the next five years and GM promising to have more than 20 EVs on sale by 2023. Plenty of other automakers -- Volvo, Volkswagen and Mercedes-Benz among them -- have also made recent EV announcements as countries like China threaten to eventually ban gas engines.
A major reason that EV battery range might not see significant increases in the near term is simply cost, which increases with more capable electric-vehicle batteries. Adding more battery to an electric vehicle also adds weight, which would affect vehicle payload -- a consideration likely to be more important as automakers launch electric trucks and SUVs.
When Nissan brought its 2018 Leaf to a technology conference in Detroit in September, the company said it was targeting value customers with the 150-mile electric range vehicle, with a price tag starting at under $30,000. That level marks an improvement over the previous version's 84-mile range, but it falls well short of the Bolt and the various Tesla models. The company does plan to release a longer-range version, but the issue of adding cost gets at a key issue for automakers.