SEOUL • It was the battery, after all.
At an hours-long presentation and news conference, Samsung Electronics detailed the results of its investigation into Note7 smartphones that overheated and burst into flames last year, triggering a costly recall and an unprecedented public relations disaster.
There were few surprises. While the firm cited flaws in battery manufacturing and design for the fiasco, it took full legal responsibility and vowed never to let it happen again.
"We sincerely apologise for the discomfort and concern we have caused our customers," said Mr Koh Dong Jin, the head of its mobile business, bowing before hundreds of reporters and cameramen at yesterday's press conference.
"We have taken several corrective actions to make sure this will never happen again."
Samsung Electronics is the most prominent unit of the giant Samsung group, South Korea's largest conglomerate, with a revenue equivalent to about a fifth of the country's gross domestic product.
It announced a recall of the oversized Galaxy Note7 in September last year after several devices exploded or caught fire, with the company blaming batteries from an affiliate, Samsung SDI.
When replacement phones - with batteries from another firm, Amperex Technology, a unit of Tokyo-based TDK Corp - also started to combust, the company decided to kill off the Note7 for good.
At yesterday's press conference, Mr Koh said electrodes at a specific location within the first batteries came in contact with each other, causing a short circuit that in turn caused overheating and fires.
The defects happened during both the design and manufacturing phases, he added.
For the second batch of batteries, a defect in another part of the unit triggered similar results.
Samsung and external experts also cited what they said were flaws in the design of the phone, including an unusually thin lining between the electrodes of the battery.
In one incident, a replacement phone emitted smoke and caused passengers on a Southwest Airlines flight on Oct 5 to be evacuated.
A total of 3.1 million devices were recalled as the authorities in the United States and other countries banned the device on flights. Reports of people injured by exploding Note7 phones raced across the Web, and nervous carriers, including Singapore Airlines, banned the gadget - and sometimes all Samsung devices - from their planes.
The total cost of the recall was estimated to be more than US$6 billion (S$8.5 billion).
Analysts said Samsung was looking to move on through yesterday's presentation, which did not implicate other devices.
"Consumers tend to be forgiving the first time," said Counterpoint Technology research director Tom Kang. "But if it happens again, it will leave a lasting mark on Samsung's quality and brand image."
Samsung had concentrated on innovative design, thinness and battery capacity rather than safety, he said.
Samsung SDI said in a statement that it had invested about 150 billion won (S$182.5 million) in safety and that its batteries would probably be used in Samsung Electronics' next smartphone model.
Samsung shares, which have been trading near record highs, were little changed yesterday.
Samsung, which is now engulfed in a corruption scandal embroiling South Korean President Park Geun Hye, said it is now focused on learning from its mistakes as it prepares to launch the next model in its Galaxy S line. Mr Koh said Samsung is not planning to unveil the S8 at the Mobile World Congress in Barcelona at the end of next month, suggesting that the company is going to take its time to make sure the product is not prone to any defect or problems.
Mr Greg Roh, an analyst at HMC Investment Securities, said: "Consumers will not tolerate even the tiniest problems in the S8... The first month of the release will be important. If no problems are detected during that one month, sales of the S8 could even surge."
BLOOMBERG, AGENCE FRANCE-PRESSE