What is a Best Power Bank?
A best power bank is that can charge for all of your devices.
How the Graphene power bank can do that?
It is for the PD protocol. The PDO: 5V 3A / 9V 3A / 12V 3A / 15V 3A / 20V 2.25A (Max 45W)
And the PPS: 3.3 -11V 4.05A. Will be suitable for all of your devices, even laptops.

What is the advantage for Graphene Battery?

Fast charge for battery itself and the devices;
Durable than common battery. Common battery lifespan is 200- 500 times, Graphene battery lifespan will be 2000+ times.
Graphene battery is safer than common battery for the good heat dissipation .

Max 45W charge for your Macbook air.

Smallest size in the world for 10000 mAh 45W power bank.
Size is : 77.4 * 56 * 26 mm: