Patent 7019542 was granted and assigned to Cadex Electronics on March, 2006 by the United States Patent and Trademark Office.
A method for testing electrochemical cells applies to a portion of a cycle of a low-frequency excitation waveform to a cell under test while maintaining an amplitude of the excitation waveform below a threshold value. In some cases a quarter cycle of the excitation waveform is used. Phase an amplitude of a response to the excitation waveform may be determined by applying formulae based on geometry.