“You could fall asleep and wake up at your destination,” said Mr. Musk, Tesla’s C.E.O., but some experts are skeptical that such cars will be ferrying passengers soon.

Germany’s largest automaker rode a wave of strong sales for years, but lagging demand and pressure from China are forcing it to consider layoffs.

E.V. batteries that are submerged in saltwater can catch fire after the floods subside, but experts say it’s a rarity.

European Union officials say the duties are meant to protect the region’s automakers from what they say are unfair trade practices in China.

The European Union is expected to support wielding tariffs on electric vehicles made in China, seeking to prevent unfair competition.

The General Motors subsidiary reached a settlement with the main auto safety regulator after one of its self-driving taxis struck a pedestrian in San Francisco last year.