Double-layer capacitors fuel cell vehicles

Fuel cell vehicles with additional energy storage are often equipped with a traction battery or a double-layer capacitor. The implementation has the following advantages ... 

Fuel cell vehicle drivetrains are also substantially more expensive than conventional and hybrid drivetrains, as seen in Figure 35.25. All of the concepts shown feature a 90 kW electric machine to propel the vehicle and a 700 bar tank holding about 5.5 kg of hydrogen. Hybrid versions include either a lithium ion battery or a double-layer capacitor unit (supercap). 

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