By Sean McLain

TOKYO -- Nissan Motor Co. finally captured for itself some of the investor excitement over electric vehicles, unveiling a new model that helped its shares rise more than 7%.

The Japanese auto maker said it would start selling a midsize electric sport-utility vehicle called the Ariya next year starting at around $40,000.

Even before the formal announcement Wednesday afternoon in Yokohama, Nissan's shares rose nearly 9% from Tuesday's closing price, ultimately finishing the Tokyo day up 7.25%.

Shares of electric-vehicle companies have been on a tear this year. Tesla Inc.'s shares have risen by more than a third in July alone. The company is now the most valuable car maker in the world, surpassing Toyota Motor Corp.

Nikola Corp., a relatively unknown maker of electric trucks, saw its shares surge after its public debut in early June. Its value briefly surpassed that of Ford Motor Co. Nikola doesn't yet sell any vehicles but says it will make a truck called the Badger to rival the Ford F-150, the bestselling vehicle in the U.S.

Nissan executives have long bemoaned the attention and investor love showered on companies like Tesla that are credited with pushing electric vehicles into the mainstream -- a feat that Nissan believes it achieved first with the Leaf, which went on sale in 2010. While the Leaf has sold nearly 500,000 units, it fell far short of initial expectations.

One reason Nissan got shunted to the sidelines, the executives say, is that the Leaf was designed to be an affordable vehicle, with unremarkable styling and performance, while Tesla aimed for luxury-car buyers with sports-car performance.

The Ariya is going for the Tesla crowd. It will cost as much as an Infiniti, Nissan's luxury brand, and go from zero to 60 miles an hour in 5.1 seconds, the company said.

"This is a no-compromise car: great acceleration, strong response, good handling," said Nissan Chief Executive Makoto Uchida.

Although Nissan has traditionally seen itself as a maker of cutting-edge vehicles, that image has taken a beating in recent years with a lineup that was older than rivals. The company relied heavily on low-profit sales to rental car agencies to pad sales. After it pulled back on some efforts to lift volume, the company lost $6.2 billion in the year ended in March.

The Ariya is unlikely to turn around the business on its own because electric vehicles, despite the investor interest, remain a fraction of the total car market. But Nissan hopes it will lead a move into more attractive cars that the company can sell for more money.

Nissan said the Ariya would be the first model to bear a new corporate logo with a sleeker font. It will have a range of between 280 miles and 380 miles, depending on the equipment package. With a high-speed charger, the car could be recharged to around 230 miles of range in 30 minutes, the company said. Using Amazon.com Inc.'s Alexa voice-recognition software, Ariya drivers will be able to turn on their lights at home before getting there, Nissan said.

Write to Sean McLain at sean.mclain@wsj.com