SEATTLE — The prospect of flying in a so-called plastic airplane was already unnerving for some.
Now there’s the added concern of Boeing’s 787 Dreamliner using the same kind of batteries that used to overheat and ignite laptops made by Dell, Hewlett-Packard, Apple and others. Battery mishaps led to the plane’s grounding this week by U.S. and European regulators.
Lithium-ion batteries produce the most energy in the lightest package at an acceptable price.
But they have had problems and continue to challenge engineers to manage the temperature generated in their chemical reactions, particularly as larger versions are produced for vehicles and now airplanes.
“It’s clear that there are some issues associated with thermal management,” said Donald Sadoway, a battery expert and the John F. Elliott Professor of Materials Chemistry at the Massachusetts Institute of Technology.
Since Sony began manufacturing them in 1990, lithium-ion batteries have led to a revolution in consumer electronics. They allow companies to build lightweight phones, cameras, power tools and other gadgets that run a day or more on a single charge.
In a phone, the batteries are thin and the heat is dissipated by the front and back of the case, which act like cooling fins, said Sadoway.
It’s a different story when batteries are nearly twice the size of a car battery, like those used in the 787.
Tesla roadsters addressed the issue by using thousands of finger-sized batteries. Now larger batteries are used in cars such as Toyota’s plug-in Prius.
Boeing is the first company to use lithium-ion technology as the main battery in a commercial airplane. The supplier of those recently won a contract to upgrade the international space station to lithium-ion batteries.
Safety remains a concern, though, especially if manufacturers try to cut costs.
Sony learned this the hard way in 2006. Errant metal flakes inside some laptop batteries it produced caused them to short-circuit, leading to sudden and sometimes spectacular fires. This resulted in recalls of more than 7 million batteries around the world, affecting major computer companies using Sony batteries.
“That’s a concern this industry has: You’re building a very energetic device; you’d better do it well or you’re going to have problems,” said Vince Battaglia, a specialist in battery design at the Lawrence Berkeley National Laboratory in California.
The 787’s lithium-ion batteries have safeguards, including controllers that trigger a shut-off if temperatures rise too much .
A Boeing executive said the 787 has a redundant safety system with four controllers on the batteries, although that’s apparently not enough to prevent incidents and satisfy regulators.