The Japanese site Makotakara, citing information from suppliers, said that adapters with USB-C for fast charging iPhone in 2018, will have to pass additional certification. Otherwise, fast charge will not work.
Additional certification is needed in order to protect smartphones from defective chargers. Manufacturers of accessories should be non-profit organizations of the USB Implementers Forum, whose members are developing USB-Apple C. in Addition, this organization has over thousands of companies. Among them — Anker, Belkin and Xiaomi. But, for instance, not Amazon, so its not the adapters will give the maximum charging rate.
According to rumors, the new charger will charge the iPhone with a speed of 18 watts. Adapters from other manufacturers will give the same power. But, if they do not consist of the USB Implementers Forum, the capacity is limited to 2.5 watts.
Previously, the Internet posted photos of the power adapter, which, presumably, will come bundled with the new iPhone. Due to problems in production, the first time it will not be sold separately.