This paper presents the development of an experimental auxiliary power unit (APU) providing 110V/60Hz output from laptop computer battery pack (10.8VDC/4.0Ah) or other available DC sources. First, a current-fed push-pull (CFPP) DC/DC converter is developed to boost the battery voltage and establish the well-regulated DC-link voltage (200VDC) for the followed inverter. Then an H-bridge single-phase inverter is established to yield 110V/60Hz source for emergency power use. In the proposed inverter control scheme, the feedback controller is augmented with a simple robust tracking error cancellation scheme to yield good output sinewave voltage waveform. The operating characteristics of the developed APU are verified experimentally. In addition to the Li-ion battery pack, the input to the proposed APU can also be the conventional storage battery, the photovoltaic cell, fuel-cell and other available DC sources.