Award Date


Degree Type


Degree Name

Master of Science (MS)


Electrical Engineering

First Committee Member

Yahia Baghzouz

Number of Pages



Hybrid electric vehicles that utilize gasoline-powered engines as a base source of power enjoy widespread customer acceptance because of their performance and economy. However, the future generation of these vehicles as well as conventional ones will have to move away from internal combustion engines due to depleting fossil fuel reserves and stricter environmental norms. Hybrid power sources composed of fuel cells and deep cycle batteries combine the high energy density of fuel cells with the high power density of batteries, offering efficient transportation without harmful emissions. This thesis describes the conversion of an electric vehicle into a hybrid fuel cell-battery vehicle and adds to the growing body of studies paving the way to a conversion to a hydrogen economy; The original all electric vehicle was powered by twelve 6 V batteries, each rated at 244 Ah ( C/20). The 72 V source supplies an 11.5 hp series excited DC motor through a solid-state speed controller. The controller is a step-down (or buck) DC-to-DC converter in which the duty ratio of the power transistor is controlled by the position of the "gas" pedal. The dual power source of the modified vehicle consists of a 5.5 kW fuel cell and six 12 V batteries, each rated at 145 Ah (also C/20). A DC-DC power converter is placed between the fuel cell and the battery bank to regulate the fuel cell source voltage, and to control the power supplied from the fuel cell and the batteries under different load conditions; Since the 5.5kW fuel cell cannot handle peak power demand alone, it is ideal to have the fuel cell provide base power up to 5.5kW and let the battery bank act as a peaking unit, providing all power past that level. This thesis contains experimental results showing this configuration.


Battery; Cell; Electric; Evaluation; Fuel; Hybrid; Performance; Vehicle

Controlled Subject

Electrical engineering; Force and energy; Automobiles--Design and construction

File Format


File Size

1812.48 KB

Degree Grantor

University of Nevada, Las Vegas




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