China's move on Friday to curb exports of graphite, a key electric vehicle battery material, will only accelerate efforts to develop alternative sources and materials, but that will take time, industry executives and analysts said. China, the world's largest graphite producer and exporter, will require export permits as of Dec. 1 for some graphite products, including spherical graphite used by automakers. China's decision may escalate trade disputes globally and spur other countries to prioritize research into alternative sources and materials, industry executives said.