Filling up without stopping – to date this is most familiar for military aircraft. The Amazon drone would also come via air, but then dock with a moving electric car and charge it while driving. At least, this is how Amazon imagines the charging process of the future, according to a published patent submitted in 2014 that has now been issued.
The driver of an electric car whose battery is running out and might not make it to his/her destination or the nearest charging station could request a charging drone via a server. This drone would, according to the patent, take off fully automatically, identify the desired car along the previously indicated route, and dock on the roof of the moving car.
Once the drone’s batteries have fed power to the electric car, the drone flies back to the charging station autonomously, charges its own batteries again, and waits for the next call. Thanks to the recharge, the electric car makes it to the nearest charging station without being stranded – at least according to the now patented idea. In practice, however, several concerns would still need to be addressed, and Amazon leaves these open in the patent application. These include the battery capacity "payload" that the drone would be able to carry, which in turn has a bearing on how far an electric car’s range could actually be extended after charging. A sufficiently fast charging process would also hardly be possibly using current technology. A widespread network of drone support bases would also have to be in place.
It is questionable whether Amazon will ever actually implement its drone-based charging method as patented. This giant eCommerce corporation has previously successfully tested its Prime Air delivery drones. Just recently, an Amazon patent for a drone logistics center that would work like a beehive has appeared.