Tesla Inc on Friday raised the size of its planned share offering to 3.1 million shares, priced at $243 apiece, and said Chief Executive Officer Elon Musk would now buy stock worth up to $25 million, more than double his initial commitment.

Tesla had said on Thursday it would raise up to $2.3 billion in new capital through shares and debt, easing Wall Street concerns about the money-losing company's ability to overcome a drop in sales and build new product lines.

The filing on Thursday also showed that it would offer a total of around 2.7 million shares, with Musk pitching in $10 million of his own money.

Tesla's plan to issue shares and convertible debt comes after the company repeatedly pushed back forecasts for turning a profit.

The company faces expensive challenges, including launching production in China, overhauling its US retail and service operations and developing new models, including the high-volume Model Y SUV and a Semi commercial truck.

Shares of the electric-car maker were up 1.5 percent at $247.80 before the bell.