YOKOHAMA, Sept 1 (Reuters) - China's BYD (002594.SZ) on Friday said it will start selling its second electric vehicle model in Japan this month, as it seeks to secure a foothold in a market that has given rise to some of the world's best-selling auto brands. The automaker in a statement said it will take orders for its Dolphin car from Sept. 20, in what could become a worry for Japanese rivals which are struggling in China against BYD and other domestic manufacturers amid a rapid shift to EVs. BYD, which stands for Build Your Dreams, will also announce Dolphin...