The Pentagon and A.I. Giants Have a Weakness. Both Need China’s Batteries, Badly.

In Northern Virginia’s Data Center Alley, windowless buildings the size of aircraft hangars are powering America’s artificial intelligence industry, which is locked in a race against China.

Yet, these data centers are increasingly reliant on China, America’s geopolitical rival, for a vital technology: batteries.

These facilities can use as much electricity as a small city, straining local power grids. Even flickers can have cascading effects, corrupting sensitive A.I. computer coding.

To cope, tech giants are looking to buy billions of dollars of large lithium-ion batteries, a field in which “China is leading in almost every industrial component,” said Dan Wang, an expert on China’s technology sector at Stanford’s Hoover Institution. “They’re ahead, both technologically and in terms of scale.”

A short drive from the data centers, at the Pentagon, military officials are sounding similar warnings, for different reasons. Military strategists, watching as modern warfare is reinvented in Ukraine, say the armed forces will need millions of batteries to power drones, lasers and countless other weapons of the future.

Many of those batteries, too, come from China.

Chinese battery dominance has long been a problem for industries like auto manufacturing, but now is increasingly being viewed as a national security threat. Currently, U.S. military forces rely on Chinese supply chains for some 6,000 individual battery components across weapons programs, according to Govini, a defense analytics firm.