Hansell was born in Medaryville, Indiana on January 20, 1898. He graduated from Purdue with a Bachelor of Science degree in electrical engineering in 1919. He was awarded an honorary Doctorate of Electrical Engineering in 1952.Hansell was an American research engineer who pioneered investigation into the biological effects of ionized air. His interest in this field of inquiry was spurred in 1932 when he noticed that the moods of one of his colleagues at Rocky Point Laboratory swung in response to the ions being generated by their equipment. He noted that when the equipment generated negative ions, his colleague's mood was upbeat. Conversely, positive ions generated a downbeat mood. Hansell researched the therapeutic possibilities of negative ions throughout his life. Current scientific studies support his findings, and negative ion therapy may be useful in alleviating depression in some people.
Hansell founded the RCA Radio Transmission Laboratory at Rocky Point, New York, Long Island in 1925, and headed the lab for over 30 years.
Hansell was also involved in radio and fiber optics research. He also suggested the invention of polarized sunglasses. He was granted over 300 US patents, including, in the 1930s, a precursor to the modern ink jet printer that could print 750 words a minute, its data received via radio telegraph. Only Thomas Edison held more patents.