More and more, big arrays of lithium-ion batteries are being hooked up to electrical grids around the U.S. to store power that can be discharged in times of high demand. But as more energy storage is added, residents in some places are pushing back due to fears that the systems will go up in flames, as a massive facility in California did earlier this year. Proponents maintain that state-of-the-art battery energy storage systems are safe, but more localities are enacting moratoriums. “We’re...