Samsung has commented on the results into its investigation into overheating and fires that led to the recall of its Galaxy Note7 smartphones. “We learned from the Galaxy Note7 issues and have made changes as a result,” the company reports. “From reassessing every step of our smartphone manufacturing process to redesigning our quality-assurance program, we are committed to implementing every [lesson] to ensure quality and safety going forward.”
The company explains that it began to get reports of problems in September 2016. It launched a global replacement program, but problems occurred with the replacement devices as well. The company subsequently halted production, and it reports that of the 3 million units sold, 96% had been returned as of today.
The company said that in an effort to identify the cause of the problem, is assembled 700 engineers who completed months of testing on more than 200,000 devices and 30,000 batteries. It also asked UL, Exponent, and TÜV Rheinland to provide objective analysis. As a result of the analysis, Samsung identified separate problems with two sets of batteries from two different manufacturers.
In the first battery, the company said, the problem stemmed from an electrode deflection and incorrect positioning of the negative electrode tip; in the second battery, an abnormal weld could lead to an internal short circuit. Timothy W. Martin and Eun-Young Jeong in The Wall Street Journal write that problems with the second batch of batteries may have been linked to the sudden ramp-up in production when devices with batteries from the first batch were recalled.
To prevent similar problems in the future, the company says it has developed an 8-point battery safety check protocol, implemented multilayer safety measures covering hardware and software, and convened a battery advisory group from academia and research centers.
The 8-point safety protocol includes a durability test, visual inspection, X-ray inspection, charge and discharge tests, a TVOC (total volatile organic compound) test to look for battery leakage, disassembly (to assess battery tab welding and insulation condition), accelerated use test, and delta OCV test throughout the manufacturing process. Some of these tests (TVOC, charge and discharge, and accelerated usage) are new tests for Samsung; others will be performed more frequently, to a higher standard, or by both Samsung and the battery maker.
Geoffrey A. Fowler and Joanna Stern at The Wall Street Journal give Samsung a C for its efforts. “Samsung was clearly serious about investigating the issue with the help of independent experts, but its explanation sometimes left us scratching our heads,” they write. “While it has developed a new 8-point battery check for future phones, we don’t have a clear sense of whether these tests will raise the bar on safety, or simply catch Samsung up to other premium smartphone makers.” They add that they would like to see Samsung take aim at the secretive industry’s self-policing.