Foldable solar panel frames for the cheapo China 88x142mm solar panels. Idea is to be able to use these in outdoor situations where a power plug is not at hand. The solar panels should deliver 5W 5V. So you will need multiple panels to boost the current (parallel) or to increase the voltage (in series). I combined these with a PD Fast Charge Solar Panel Power Bank Charge Voltage Controller that can take up to 18v and deliver up to 3A at a voltage of 5V/9V/12V. That should allow fast charging.

Using a power bank is recommended.

I used the clothes hangers from the dry cleaners to create the rods to fixate the joints.

Size is 10x15cm per panel and 6mm high.