June 20 (UPI) -- Tesla Friday signed a $556.8 million agreement to build a grid-scale battery storage station in China. The deal is with China Kangfu International Leasing Co., as well as the Shanghai local government . It's the first Tesla large-scale battery storage facility in China. In a statement on Chinese social media site Weibo, Tesla said, "Tesla's first grid-side energy storage power station project in mainland China has been officially signed .The grid-side energy storage power