Patent attributes
A method of obtaining information relating to the charge capacity of one or more cells utilizing information from the initial discharge period of the cell or cells. The method involves measuring a variable cell parameter for at least a part of an initial period of discharge during which the cell voltage initially decreases to a through voltage and then increases to a plateau voltage (the Coup De Fouet period), and relating the variable cell parameter to reference information to obtain the absolute or relative charge capacity of the cell or cells. An estimation model for predicting the absolute or relative capacity of a battery includes input for a variable battery parameter and one or more battery operating conditions and/or battery condition, reference information, compensation means determining a correction factor for the variable battery parameter, and calculation means relating corrected variable battery parameter to absolute or relative battery capacity.
