Question about Sandberg Solar Charger

As I don't have an iPhone, I can't answer this question. But it charges my Android with 15 watts, the maximum that this Android is capable of charging - just like at the socket. As far as I know, the iPhone 15 charges at 20 watts. According to the specifications, it should therefore be able to charge with 20 watts.

I returned the item because I couldn't charge my power bank with it.
However, the Iphone 13 worked fine. I no longer know how long it took.
Without a power bank, the sun is permanently important. It immediately works much slower and worse with some cloud cover.

I cannot tell you as I am always charging a power bank with the charger.