What's Behind Samsung's Phone Fires?

A Samsung Galaxy Note 7 phone caught fire on 9 Oct., two days before Samsung Electronics announced that it is permanently discontinuing production of that model.
Photo: Shawn L. Minter/AP Photo
A Samsung Galaxy Note 7, flame roasted, from an as yet unknown heat source.

There’s never a good time for a corporation to get a black eye, but now is a particularly bad time for Korea’s Samsung. The company’s recall of 2.5 million Galaxy Note 7 smartphones, and its shutdown of sales and production also call attention to its recent recalls of other, unrelated products.

“What was remarkable here was that this was the world’s leading company for batteries and for consumer electronics,” says Cosmin Laslau, an electrochemistry expert and technology analyst for Lux Research. “It doesn’t get much more high profile than this.”

Though only 35 fires have been reported so far, one’s enough to ruin your whole day. A single blazing battery grounded a fleet of Boeing 787 Dreamliners some years back—one reason why in September, air safety regulators told people to shut off their Galaxy phones before packing them for a flight.

Right now, nobody in or out of Samsung really knows what’s going on. Investigations of the fires are still unpublished, but today Bloomberg News reports that Samsung has told Korea’s technology standards agency that the problem may involve a manufacturing error. According to that confidential note, the error brought negative and positive poles into contact, causing a short circuit. Samsung SDI Co. was the main battery supplier for the Galaxy Note 7, Bloomberg adds. 

Amperix Technology Limited has also provided some batteries for Samsung’s phone. If all the bad batteries had been in one batch, switching from one supplier to the other should have solved the problem—but it didn’t. “The chances that two suppliers are having similar issues are very low, so there must be more to the story,” Laslau says.

Why didn’t more of the phones burst into flames? And why didn’t the problem emerge right away? Does fire result only when you get a perfect storm of mishaps in several elements of the phone?

The random and rare nature of the fires doesn’t look like what you’d get from a straightforward manufacturing problem, says Bor Yann Liaw, a materials scientist who specializes in batteries at the Idaho National Laboratory, in Idaho Falls. “It is unlikely a [battery] design flaw either, since the products have been tested and have passed all safety requirements. This is probably a system design flaw that causes battery charging to derail from the normal process.”

“It could be a lot of things,” Laslau says. “A production process with impurities, or something to do with the separator [a membrane that prevents the electrodes from coming into contact, causing a short circuit]. Or the batteries could be fine but the energy management system could be charging them too aggressively.”

You can tweak any or all of these elements, but if you do, you’ll sacrifice performance and cost. Any supplier that did that would risk losing the contract to the next guy. 

“A lot of suppliers of batteries are under pressure to charge faster and pack in a lot more specific energy than ever before,” Laslau says. “Where is the tipping point where a major developer will say it will increase its price by 10 to 20 percent in order to make the batteries safer? This may force that type of introspection in the industry.”

This post was corrected on 17 October to clarify a statement about design flaws.

Advertisement

Newsletter Sign Up

Sign up for the EnergyWise newsletter and get biweekly news on the power & energy industry, green technology, and conservation delivered directly to your inbox.

Advertisement