UC Davis Institute of Transportation Studies

The development of ultracapacitors (electrochemical capacitors) suitable for hybrid-electric vehicle applications has continued in various countries around the world even though automobile manufacturers have been slow to adopt the technology. Several of the new carbon/carbon and hybrid ultracapacitor devices being developed have been tested, as well as application of those devices in micro-hybrid and charge sustaining hybrid vehicles. Performance data for the ultracapacitors have been collected and analyzed. The influence of the ultracapacitor technology and the size of the energy storage unit (in Watt-hours) on the fuel economy improvement is also of particular interest.