DaimlerChrysler's PNGV Concept Vehicle represents the fruits of a marriage between DaimlerChrysler's proprietary efforts in developing advanced vehicle body and chassis technologies applicable to PNGV goals and a mild hybrid electric (Mybrid) powertrain developed under government contract. The powertrain was developed as a part of DaimlerChrysler's "U.S. Hybrid Propulsion Systems Development'' Subcontract No. ZAN-6-16334-01 with the Midwest Research Institute under DOE Contract No. DE-AC36-83CH10093. Energy management is key to efficient vehicle operation, whether it be between individual battery cells, between the heat engine and the electric drive system or between the total vehicle and the powertrain. DaimlerChrysler's PNGV Concept Vehicle energy management strategy operates at all three levels to maximize overall vehicle efficiency in targeting the PNGV goals.