Samsung yesterday announced the results of extensive testing into the cause of the severe overheating of Galaxy Note 7 smartphones. These photos supplied by Samsung reveal the scale of that testing.
Samsung gave 700 engineers the task of conducting charge/discharge tests on 200,000 devices and 30,000 batteries.
Batteries were also tested separately from the Note 7, and the same failure rate provided evidence that the batteries were faulty, not the phones.
Tests included wireless charging as well as USB charging.
Testing with the backplate removed showed the Note 7's water resistance did not contribute to the problem.
Results were the same whether or not the iris scanning feature was active.
Applying high voltages to the USB-C port did not trigger overheating.
A variety of preinstalled and downloaded software was tested...
... including abnormal software conditions.
Following the investigation, Samsung developed a new eight-point battery safety check to help prevent a recurrence. This includes testing pressure on an edge (such as when a phone is in a trouser pocket and the owner leans against a counter)...
The battery check also tests pressure on a point (such as a small, hard object in the same pocket)...
Another battery check tests pressure across the entire surface (such as sitting with a phone in the back pocket).
The durability of batteries is tested.
The outside of the batteries is checked visually...
...and the internals are x-rayed.
Another test checks for leakage of any volatile organic materials.
Sampled batteries are disassembled to check they meet specifications.
The open circuit voltage from the battery is checked at various stages of manufacture.
Samsung yesterday announced the results of extensive testing into the cause of the severe overheating of Galaxy Note 7 smartphones. These photos supplied by Samsung reveal the scale of that testing.