Rinspeed is renowned for producing exotic concept vehicles for the Geneva Motor Show each year - the aquatic sQuba and shape-shifting iChange being two prime examples. The 2012 show looks like it will be no exception. We've seen external battery packs designed to increase the battery life of a smartphone, and now Rinspeed's "Dock+Go" concept brings the same idea to electric vehicles in the form of a vehicular backpack that docks to the rear of an electric vehicle to extend not only their range, but also their cargo-carrying capabilities.

The modular Dock+Go mobility system from the fertile mind of Rinspeed founder and CEO Frank M. Rinderknecht sees single axel packs that can be attached or detached from an electric vehicle depending on the demands of the day.

In addition to an "energy pack" that could extend the range of an electric vehicle by adding a combustion engine, range extender, or batteries powered by a fuel cell to the rear of a vehicle, Rinderknecht also envisions other packs to extend the capabilities of the host vehicle in other ways - a pack for pizza delivery cars featuring an integrated heated box to keep pizzas hot or a toolbox pack with customized spaces for a tradesperson's tools, for example.

The modular system would also allow work packs to be swapped out at the end of the working day for recreational packs customized for various activities, such as camping, golfing, skiing, or hitting the beach.

While Rinderknecht chose the electric smart fortwo as the basis for a demonstration of the concept, he says the range-extending packs - which would result in what he calls "Vario-Hybrids" - could be designed for any electric car. Rinspeed will be presenting its "Dock+Go" concept at the 82nd Geneva International Motor Show, which runs from March 8-18, 2012.