BERLIN/FRANKFURT - Daimler and its Chinese joint venture partner BAIC Motor Corporation agreed to upgrade the Mercedes-Benz factory in Beijing to make electric cars, the German carmaker said on Thursday. At a signing ceremony in Berlin attended by German Chancellor Angela Merkel and Chinese Premier Li Keqiang, Daimler signed a framework agreement to upgrade production facilities at Beijing Benz Automotive Co., Ltd. (BBAC), to make New Energy Vehicles, a label for so-called lo