Powerful and lightweight, lithium-ion batteries are the perfect power source for modern gadgets. But ubiquitous as they are, their short history has also been fraught with problems — they have caught fire in cellphones, laptop computers and electric cars, and even destroyed a small Navy submarine.



Now, federal investigators are trying to determine why a lithium-ion battery caught fire in Boeing’s long-awaited787 Dreamliner last week, and they have grounded the planes until they figure it out.



While Boeing officials insist that the failure never endangered passengers or the plane’s integrity, the prospect that batteries would leak flammable fluids and smoke on flights packed with passengers has opened perhaps the most unnerving chapter in the technology’s relatively short life.

For Boeing, the development of the 787 represented a push into new technology and energy efficiency, and the company staked much of its future on the plane. It turned to the new batteries for many of the same reasons that Silicon Valley and Detroit have: they pack a lot of energy in a small package and, unlike older batteries, can be charged rapidly and frequently without loss of power.