Patent ID: 6816797
Filing Date: 2004-11-09
Classification: G01R

Abstract:
An apparatus for measuring impedance and voltage characteristics of cells of a multi-cell electrochemical device, the apparatus comprising:a voltage measuring means including a plurality of inputs for connection across a plurality of measuring points between cells of the electrochemical device, to generate voltage signals indicative of the measured voltages, the voltage measuring means providing a plurality of primary channels for the measured voltages, there being one channel for the voltage across adjacent measuring points; and wherein the voltage measuring means includes a channel splitter for separating out components of the measured voltages across adjacent measuring points from the primary channels, the channel splitter having first channels for providing DC components of the measured voltages and second channels for providing AC components of the measured voltages; a load, connectable in series with the electrochemical device, and adapted to draw a DC current with a superimposed AC perturbation current; and a controller connected to and controlling the voltage measuring means and the load, for controlling the characteristics of the load and for receiving the voltage signals from the voltage measuring means, wherein the controller is adapted to control the load to provide desired DC and AC load current characteristics.