TOKYO Japan is heavily investing in a new kind of ultra-thin, flexible solar panel that it hopes will help it meet renewable energy goals while challenging China 's dominance of the sector. Pliable perovskite panels are perfect for mountainous Japan, with its shortage of flat plots for traditional solar farms. And a key component of the panels is iodine, something Japan produces more of than any country but Chile. The push faces some obstacles: Perovskite panels contain toxic lead, and, for now,