Tesla's stock rose 1.1 percent in Monday's premarket trading after Warren Buffett praised CEO Elon Musk during the Berkshire Hathaway annual shareholders meeting. Buffett called Musk a "brilliant, brilliant guy" who has a way of dreaming about the future, while his business partner Charlie Munger added that Musk "likes taking on the impossible job and doing it." Additionally, Tesla is set to hold a ceremony at its new lithium refinery in Texas, which comes about two months after the company broke ground on the $375 million plant. Tesla's stock has recently been on a four-week losing streak but rebounded on Friday and Monday.