Sandberg Solar 4-Panel

Here comes a cavalryman: the largest, heaviest and most expensive model tested delivers 79.7 watt-hours of energy via three outputs, including a 20-watt USB-C port. It takes just under seven hours to fully charge; it refuels 1 watt hour twice as fast as the competition.

Combination of solar charger and power bank. Thus very flexible to use. Also acceptable in terms of size and weight, even when carried in a backpack.