Elektr-O-Mat, Range Extenders.

Click tip: You want to drive electric but don’t know what to get? Should you get an electric car, a pedelec or an electric scooter? The Elektr-O-Mat can help you figure out what mode of electric transportation fits best. Unfortunately, the tool only exists in German for now.
idw-online.de, livinglab-bwe.de

Study tip: “Range Extenders for Electric Vehicles Land, Water & Air 2015-2025” by IDTechEx predicts that some eight million vehicles with range extenders will be built in 2025. It also compares different technologies, taking into account lower energy needs, i.e. due to the extension of fast charging networks.
idtechex.com