Patent ID: 6167349
Filing Date: 2000-12-26
Classification: G01R

Abstract:
A method for evaluating a battery jar, comprising the steps of:a) applying a measured current load to said battery jar in a stepwise manner;b) measuring the voltage across said battery jar before said current load is applied;c) measuring the voltage across said battery jar at least once during the application of said current load;d) determining, from the at least one voltage measurement from the step c), the voltage across said battery jar immediately after said current load is applied;e) calculating, from the measured voltage from the step b) and the determined voltage from the step d), the ohmic resistance of said battery jar;f) measuring the voltage across said battery jar at least once more during the application of said current load if the step c) provided only one measurement;g) determining, from at least the second voltage measurement from the steps c) and f), the steady state voltage across said battery jar in response to said current load; andh) calculating, from the determined steady state voltage from the step g) and the determined voltage from the step d), the charge transfer resistance of said battery jar;wherein the step a) of applying a measured current load includes the steps of:a1) providing a first series of pulses of said measured current and each of a first duration; anda2) providing a second series of pulses of said measured current and each of a second duration;wherein the step e) of calculating the ohmic resistance utilizes measurements taken during said first series of pulses;wherein the step h) of calculating the charge transfer resistance utilizes measurements taken during said second series of pulses; andwherein said second duration is greater than said first duration.