WASHINGTON, May 22 (Reuters) - The U.S. Energy Department told lithium battery company Microvast Holdings (MVST.O) it will not award it a $200 million grant, a source familiar with the matter said on Monday, after lawmakers cited concerns over its alleged links to China's government. The department had been in talks with Microvast over the grant to help build a plant in Tennessee. The grant stemmed from the $1 trillion 2021 bipartisan infrastructure law. Two Republican lawmakers criticized the decision to grant the funding in a letter last December to Energy Secretary Jennifer Granholm, saying Microvast had ties to the...