PowerBook with solar battery is useful not only because you can write notes or drawings on its pages. Its main advantage is in possibility to charge smartphone via solar energy thanks to built-in in cover solar cell panels.
Best solar battery
Developers say that device has the most productive batteries SunPower, which allows recharging with the same speed as via socket to each device. For instance, iPhone6 will be charged already in 2.5 hours and iPhone 6 plus — in 5 hours. PowerBook has size of 168x238x14 mm and weight of 462 g.
Cover with solar panels can be set at any angle. Most importantly, sunlight beams should fall into cover perpendicularly to surface for the maximum efficiency and quickness of charging gadgets.
Charging process is active only under direct sunlight beams. Thus, if clouds block them, PowerBook will automatically disconnect with gadget and then connect at optimal conditions.
Powerbank is accessible for advance order for $70, and deliveries starts on October 2016.