Much is being said about the problem of the batteries of some models of iPhone 6s that were sold, especially in the first units that hit the market at the end of last year. This issue causes the device to shut down suddenly, even though it still has more than enough battery percentage left to continue operating smoothly. As it's usual Apple has not commented about it until you have found the source of the problem. Apparently the problem comes from a problem with the air sensor, which forces the batteries to stop working to avoid other more serious problems.
Being a factory problem, Apple has created a free battery replacement program, a program that all users who have purchased the terminal between the months of September and October last year can go to. But it seems that despite the good faith on the part of Apple, the body in charge of supervising batteries in South Korea, wants to clarify the real problem of the batteries of these models and has opened an investigation in this regard, which he did not do with the explosions of the Galaxy Note 7, since Samsung batteries are manufactured by the company itself without going through this regulator at any time.
Apple continues to affirm by active and passive that nLet's never use cables and chargers that are not certified by them, such as those sold by the company or the MFIs. It seems that Apple always shields itself in this regard when problems with the batteries appear, without taking into account that most users always use the official charger that comes with the iPhone, I doubt that they will go down to the Chinese store to buy a cheap charger so as not to spend the original and put the device at risk, which is not precisely characterized by being economical.