The Galaxy Note 7 had what was probably the shortest run in cell phone history. Samsung’s flagship phablet launched on August 19. The company issued a voluntary recall notice less than a month later on September 15. About one month later, on October 13, the U.S. Consumer Product Safety Commission (CPSC) stepped in and issued a mandatory recall of the faulty device.
The recall efforts stemmed from several of the devices catching fire or exploding while being charged. During its initial investigation, Samsung verified 35 incidents of catastrophic battery failure in Galaxy Note 7s. According to Digital Trends, there have now been over 90 incidents of the phone overheating in the U.S. alone. Twenty-six people have reported burn injuries, and 55 have incurred property damages.
Initially, Samsung blamed one of its battery suppliers, stating that the problem was a faulty battery cell and not a flaw in the phone design. However, after exchanging several devices during the first recall, batteries were still exploding and overheating. At that point, Samsung admitted that it did not know what was causing the failures and had not been able to reproduce the problem in the laboratory.
It has now been nearly two months since the CPSC issued its recall of the Galaxy Note 7, and engineers may have found the cause of the battery failures. Although there has been no official word from Samsung, engineers at Instrumental believe they have discovered the source of the problem.
Instrumental is a company that “helps hardware companies find and fix issues caused by workmanship, part quality, process, and design.”
According to Instrumental engineer Anna Shedletsky, the batteries were being compressed due to a design flaw in the phone. Over time, batteries will swell as they are charged and discharged. Battery compartments need to have about 10 percent more space than the total width of the battery to allow for expansion. In the unit they examined, there was no space (or ceiling) for battery swell.
“The battery and adhesive was 5.2 mm thick, resting in a 5.2 mm deep pocket. There should have been a 0.5 mm ceiling. This is what mechanical engineers call line-to-line — and since it breaks such a basic rule, it must have been intentional. It is even possible that our unit was under pressure when we opened it.”
Because of this design, batteries in Galaxy Note 7s were becoming compressed after a month or so of charging. Thin separator layers between cells coupled with this compression led to overheating and fires. In some instances, the pressure led to the battery exploding.
According to Shedletsky, “Samsung stated that these separator layers [between electrolyte cells] may have been thin to start with due to aggressive manufacturing parameters.”
Further compression from battery swell, as well as physical pressure from people sitting on the device, was causing the separators to fail. When positive and negative electrolyte layers touch or mix, you get heat and often explosions.
Anna is of the opinion that this design flaw was intentional on Samsung’s part. That is not to say that they were trying to make a faulty device, but that they were “pushing the boundaries” in the pursuit of innovation.
She speculates that “Samsung’s innovative battery manufacturing process was changing throughout development, and that the newest versions of the batteries weren’t tested with the same rigor as the first samples.”
Shedletsky and her colleagues say that the only solution to the problem without changing the phone’s design would have been to use “a smaller battery using standard manufacturing parameters,” but then the battery life would have been reduced below “competitive” levels.
“It’s now clear to us that there was no competitive salvageable design.”
With no “salvageable design” options available, Samsung had no choice but to completely pull the Galaxy Note 7 and start over from scratch.
Despite the two recalls of the device, there are still many phones that have not been turned in for refund or exchange. According to the Verge, there are still approximately 150,000 Galaxy Note 7 units that were sold in the United States that are still in the hands of consumers. To Samsung’s credit, the company has done almost everything it can to get the phones back.
The Korean manufacturer initially offered full refunds or exchanges for any other Samsung device with a reimbursement of the difference. Shortly after that, it issued a patch to the phone’s software that prevented it from charging the battery over 60 percent. There had been rumors that the last resort would be to disable the phones entirely through software means or through mobile carriers. Those rumors got a little more substantial today with reports that Samsung intends to do just that.
The Verge received a screen capture allegedly from a Galaxy Note 7 owner showing a message from US Cellular that read, “As of December 15th, Samsung will modify the software to prevent the Galaxy Note 7 from charging. The phone will no longer work.”
The Verge reached out to Samsung and US Cellular, and both declined to comment. While refusing to weigh in on the matter does not validate the rumor, it does not invalidate it either. It seems logical that the company would take all measures available to eliminate that risk of a potential personal injury or wrongful death lawsuit.
It is also likely that they would not make such a move without notifying Galaxy Note 7 owners in advance. Therefore, if the image that the Verge received is legit, there are others who have received similar messages from their carriers. If you currently own and are using a Galaxy Note 7 despite the recall, warnings, and limits placed on battery charging, let us know in the comments below whether you have or have not received a similar notice.
Update: Digital Trends just reported that Samsung has officially confirmed that they will be disabling devices. On December 19, the company will issue an update that will permanently disable the remaining phones.
[Featured Image by Drew Angerer/Getty Images]