Republican congressmen are investigating Ford’s partnership with Chinese battery maker CATL, according to news reports.

The chairmen of the House Select Committee on the Chinese Communist Party and the House Ways and Means Committee sent Ford a letter Thursday seeking more details about the partnership.

Ford announced plans for a $3.5 billion battery factory in February utilizing technology and services by CATL, the world’s biggest maker of batteries for electric vehicles.

The congressmen expressed disquiet that the relationship between the Dearborn, Mich.-based automaker and the Chinese concern might involve forced labor at a company CATL has had ownership interest in in Xinjiang, saying that CATL moved to maintain control of the company while giving the appearance of divesting itself of the operation.

The committees also expressed concern that several hundred Chinese workers would work at the Ford factory.

When Ford announced the battery plant project, it said the LFP battery chemistry to be used there “helps reduce reliance on critical minerals such as nickel and cobalt and is in line with Ford’s work to create an EV supply chain that upholds its commitments to sustainability and human rights.”

Ford said in news reports that it will respond to the committees' letter and that it’s committed to human rights.

The Biden administration has worked to increase U.S. EV production and materials sourcing to decrease reliance on Chinese markets, offering incentives and loans to companies that pursue such operations.

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