So I bought this 5V 1A solar panel that can be used e.g. to charge your smartphone accroding to the product description.
When I measure the voltage using a multimeter I measured 6.9 V. A little bit higher than my expectations. However, when I measured the Amps it was ~0.3 A, less than I expected at blazing sun.
I decided to add a 6 ohm resistor and measure V and A again. To my surprise I measured to voltage to just 1.6 V and the current to 0.2 A. Later I read that I/V ratio for solar panels is not trivial...
My question: How should this solar panel be suitable to be used for charging a smartphone when a smartphone clearly needs 5V?