A:AnswerYes!
This works great with my Samsung S10 Android Smartphone, and it supports Fast Charging up to 18W!
That's more than enough for my phone which does 10W Fast Charging.
A:AnswerWhen was the last time you charged the charger? I know right out of box, I did have to charge mine before use. It will do the flashing indicator lights if the charger itself is low power wise.
A:AnswerLithium battery.
Btw, if you want to take it with you while traveling by air, you can take it in your carry-on bag but you can't take it in your checked luggage.