According to a recent report, Audi is developing an A7 with a fuel cell powertrain.
Little is known about the model, but Autocar is reporting Audi will begin testing the car towards the end of August. They go on to speculate that Audi is developing the car as an extension of their eco-friendly "-tron" range.
There's no word on how the powertrain will work, but Fuel Cell Vehicle (FCVs) normally generate electricity via an electro-chemical reaction between hydrogen and oxygen. This electricity is then sent to a battery or an electric motor.
Audi's last FCV, the Q5 Hybrid Fuel Cell (HFC) prototype, used a polymer electrolyte membrane fuel cell, two high-pressure hydrogen cylinders and a 1.3 kWh lithium-ion battery. The system sent power to two electric motors which enabled the model to have a combined maximum output of 122 HP (90 kW) and 420 Nm (310 lb-ft) of torque.