Bad battery design responsible for Boeing Dreamliner grounding, expert says

A charred lithium ion battery at the center of the worldwide grounding of the Boeing 787 Dreamliner showed evidence of “thermal runaway” -- which is indicative of a design problem, experts tell

The All Nippon Airways plane made an emergency landing Wednesday morning in western Japan after its pilots smelled something burning and received a cockpit warning of battery problems. Nearly all 50 of the 787s in use around the world have since been grounded.

The battery’s burned insides indicate it operated at a voltage above its design limit, a Japanese investigator said Friday. That’s a clear sign of an out-of-control chemical reaction, explained Reginald Tomkins, a professor of chemical engineering at New Jersey Institute of Technology.

'I don’t think it’s a problem with the actual battery set up. Lithium ion has been around for 30, 35 years … it seems to be a design problem.'

— Reginald Tomkins, a professor of chemical engineering at New Jersey Institute of Technology

“Every battery runs on a chemical reaction, and chemical reactions normally involve heat given out. Sometimes with a battery, if the rate of discharge is fast, this heat is produced,” Tomkins told “If it isn’t taken away, then you get a buildup of temperature and fire and smoke.”

But that’s par for the course with lithium ion batteries, a proven technology that’s been well studied for decades, he said. So what could have led to such an issue in an airplane?

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“I don’t think it’s a problem with the actual battery set up. Lithium ion has been around for 30, 35 years … it seems to be a design problem,” Tomkins said.

The 787 relies more than any other modern airliner on electrical signals to help power nearly everything the plane does. It's also the first Boeing plane to use rechargeable lithium-ion batteries for its main electrical system.

GS Yuasa Corp., the maker of the lithium-ion batteries used in the 787s, said Thursday it was helping with the investigation but that the cause of the problem was unclear. It said the problem could be the battery, the power source or the electronics system.

Just don’t blame the lithium tech itself.

Lithium ion batteries have led to fires and even explosions in Sony laptops and Apple iPhones -- high tech gizmos with incredibly tiny layouts that pack batteries into the barest millimeters of metal, often leading to heat build up. But the chemistry is sound, Tomkins said.

“They’ve been around for a long time. And the fundamental thing of the battery is okay,” he told

Lithium ion batteries have higher voltages and therefore more power than other metals, leading to their popularity in many industrial applications, explained Hans Weber, president and owner of TECOP International Ltd, a San Diego-based aviation consulting firm and former adviser to the FAA.

“It can discharge its energy at a much higher rate. So if you need a real power spike, to start an engine maybe, the lithium ion battery does that very well,” Weber told

“Everyone is going to lithium batteries because of the huge advantage,” he added. “The Fisker has it. The new CityCar that will be introduced alter this year has it. The Tesla S has them. Everyone.”

The NTSB has not yet released its findings, but there are other possibilities. The battery itself may not be flawed, for example -- this might just be a bad batch, Weber said.

“You might remember there was a problem with fires in the Volt battery pack? At first that was blamed on GM, that they had not properly designed the enclosure. It turned out that it wasn’t the enclosure, it was a bad battery batch.”

Tomkins agreed that this may be an issue -- but he thinks otherwise.

“It could be a difference in the design of a batch, but I doubt it. It’s a possibility though,” he told

Whether it’s one batch or the entire fleet, Boeing faces a financial boondoggle, and the batteries themselves are the least of its worries. Mark Rosenker, a former NTSB chairman, told Reuters that Boeing conducted over 1.3 million hours of testing before deciding the lithium-ion batteries were safe to use on the 787, and the company had to satisfy additional rigorous tests to be granted "special condition" by the FAA to use the batteries.

If Boeing were forced to replace the batteries in the Dreamliner, that rigorous testing would be a fresh problem.

“The redesign is much smaller than the extensive testing that would go on, that would be time consuming. We’d be talking about months. Many months.”

The Associated Press contributed to this report.