“We knew that G.M. was getting low-cost inflaters from others,” said Chris Hock, a former member of Mr. Taylor’s team who left Autoliv in April. “That was a dangerous path.”

Even with the record recall, deadly accidents and research critical of ammonium nitrate, Takata continues to manufacture airbags with the compound — and automakers continue to buy them. The airbags appear in the 2016 models of seven automakers, and they are also being installed in cars as replacement airbags for those being recalled.

Takata said in a statement that it had taken steps to protect the ammonium nitrate it uses against temperature changes, which along with moisture are the main factors contributing to its volatility. The manufacturer said it was also studying, along with safety regulators and some automakers, inflaters with a drying agent “to better understand and quantify their service life.”

‘It Turned It Into Shrapnel’

The new airbag came not a moment too soon for Takata.

The Japanese supplier had been making seatbelts in the United States since the mid-1980s, but its airbag business, which it began in earnest in the 1990s, was in trouble.

A previous generation of airbags supplied to Nissan had the problem of deploying too forcefully. Those airbags were linked to at least 40 eye injuries in the 1990s.

Takata began experimenting with alternative propellants. But in 1997 its inflater plant in Moses Lake, Wash., was rocked by a series of explosions that destroyed equipment and greatly curtailed production, according to insurance claims made by the company at the time.

After the blast, Takata was forced to buy inflaters from competitors and airlift them to automakers across the country. The company’s American business struggled “to maintain corporate viability,” Takata said in a lawsuit filed against its insurer.