Elon Musk, the widely followed chief executive of electric car maker Tesla Motors Inc, tweeted several optimistic statements about the company's sagging China operations, sparking a sharp rebound the company's stock. On his Twitter feed around midday, Musk said that he was "very optimistic about Tesla's long-term future in China, despite our earlier mistakes." He also tweeted that he visited Chinese President Xi Jinping and other government officials and expressed "great faith" in Tesla's embattled team in China. In one of his tweets, Musk said the company plans to unveil "a major new Tesla product line -- not a car" on April 30 at its southern California design studio. The announcement will involve a Tesla-branded storage battery for the home, according to a source familiar with the plan. Musk previously announced the battery in February during a year-end earnings briefing. The company's stock has been battered this year by investors concerned about the automaker's failure to hit sales targets in China and the departures last year of two top Tesla executives in that country. In February, Reuters disclosed that Musk was prepared to fire overseas executives after weak Chinese sales cast doubt on his ambitious global expansion plans, according to people with knowledge of the matter. Tesla shares had slumped in mid-January. "We'll fix the China issue and be in pretty good shape probably in the middle of the year," Musk said at the time. In an internal email to Tesla managers in late January, Musk threatened to fire or demote country managers if they are "not on a clear path to positive long-term cash flow," according to two people who had seen the email. (Reuters)