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SHANGHAI, Dec 12 (Reuters) - Chinese electric vehicle $(EV)$ maker Nio will seek to improve efficiency and cost control as it seeks to spur sales growth that is two years behind schedule, its CEO said on Thursday.

William Li told reporters at an event in Shanghai that it will also start production at its third factory in the second half of next year, and that it aimed to achieve monthly deliveries of 20,000 cars from its second, Onvo brand, by March 2025.

The company has had 30-40% growth in the last three years but that was not satisfactory, he said. Li said last month the company aims to double sales in 2025 from this year.

Nio, one of China's largest EV players by sales, has been fighting price competition in China by broadening its customer base and boosting sales with cheaper models. The company has also trimmed its workforce and deferred long-term projects that would not contribute to financial performance within three years.

It launched its affordable Onvo brand in May, with the Onvo L60 SUV with a sticker price starting at 219,900 yuan ($30,300). Tesla's Model Y starts at 249,900 yuan in China.

Asked about the United States' latest curbs on semiconductor-related exports to China, Li said they were evaluating the impact.

There were sufficient domestic alternatives for high computing power chips in cars but a bigger challenge was to replace the hundreds of thousands of foreign chips in EVs that cost $1 or $2 each with domestic options, he said.

(Reporting by Zhang Yan and Brenda Goh; Editing by Clarence Fernandez and Barbara Lewis)

((clarence.fernandez@thomsonreuters.com; +6568703861; RM:clarence.fernandez.thomsonreuters.com@thomsonreuters.net))