The Kentucky autoworkers, who want to join the United Auto Workers, filed for a union election Tuesday, a key development in the union’s campaign to organize Southern auto-factories and EV battery facilities.

Workers at a Ford Motor Co. joint-venture battery plant in Kentucky have formally asked the federal government to hold a vote on joining the United Auto Workers, the union said. Employees at the BlueOval SK factory publicly launched their campaign to join the UAW in November after a supermajority signed union cards.

The automaker has long faced pushback over its plan to license Chinese battery technology at its multibillion plant in Michigan.

The U.S. Defense Department has added the world's largest electric vehicle battery maker, along with Chinese tech giant Tencent Holdings, to a list of companies that it says work with China's military,

The Department of Defense on Monday added the battery giant CATL to its list of "Chinese military companies" operating in the United States.