A fundamentally new approach to battery performance analysis using DFRATM/DPISTM technology

Digital Frequency Response Analysis (DFRA^TM) combined with Discrete Frequency Immittance Spectroscopy (DFIS^TM) provides an important new technique for evaluating battery performance parameters. The cell/battery is excited with a periodic current, and its complex impedance Z (or admittance Y) is determined at the excitation´s fundamental frequency using DFRA^TM By measuring complex Z (or Y) at n discrete frequencies, and combining the 2n measured quantities using DFIS^TM, the technique evaluates elements of a unique 2n-element equivalent circuit model of the cell/battery. The 2n element values contain virtually the same information as the continuous Z (or Y) spectrum expressed over a wide frequency range. In addition, the elements themselves represent actual physical and/or electrochemical processes occurring within the cell/battery. Accordingly, their values yield potentially useful new information concerning cell/battery performance