Tesla posted a surprising profit of 143 million U.S. dollars in its latest quarter, raising hopes the electric car pioneer may finally be turning the corner after posting mostly losses during its first decade as a publicly held company.

The positive results announced Wednesday came after Tesla lost 1.1 billion U.S. dollars during the first half of the year. That had caused many investors to lose faith in the company even as it boosted sales of its vehicles.

Shares rose by nearly 21 percent to 307.12 U.S. dollars after hours on the unexpected news, crossing 300 U.S. dollars for the first time since March 1 after record deliveries and cost cuts ensured a profitable third quarter.

The company also said production in Shanghai and for Model Y are ahead of schedule, which it now expects to launch by the summer of 2020.

"Gigafactory Shanghai was built in 10 months and is ready for production, while it was roughly 65 percent less expensive (capex per unit of capacity) to build than our Model 3 production system in the U.S."

Model 3 vehicles made in the Shanghai factory will have roughly the same margins as those made in Fremont, California, Tesla chief financial officer Zach Kirkhorn said.

(With input from AP and Reuters)