Abstract: A battery is subjected to a discharge current pulse that is normalized to its capacity. The battery voltage is measured before, during and after the pulse, and various parameters are calculated therefrom. The parameters are adjusted depending on both the value of the nominal or maximum cut-off voltage of the battery and on its open circuit voltage prior to the pulse. Based on the open circuit voltage, one of multiple different analysis paths is selected, each representing a different state of charge range. The analysis selected involves a comparison of the adjusted parameters with a set of thresholds that are specific to the selected analysis and that depend on the desired cut-off point between good and poor state of health. Batteries of different nominal voltages, capacities and chemistries can be tested without knowing their state of charge and without the tester having been calibrated for a specific battery model.

Abstract: Methods and apparatus for testing electrical storage batteries monitor magnetic susceptibility of components of the storage batteries. In some embodiments, magnetic susceptibility of a plate in a lead-acid battery is determined to provide an indication of the state of charge of the battery.

Abstract: Methods and apparatus for testing electrical storage batteries monitor magnetic susceptibility of components of the storage batteries. In some embodiments, magnetic susceptibility of a plate in a lead-acid battery is determined to provide an indication of the state of charge of the battery.

Abstract: Methods and apparatus for testing electrical storage batteries monitor magnetic susceptibility of components of the storage batteries. In some embodiments, magnetic susceptibility of a plate in a lead-acid battery is determined to provide an indication of the state of charge of the battery.

Abstract: A method for evaluating the conditions a battery comprises applying a discharge pulse to the battery and monitoring a response of the battery to the discharge pulse. In some embodiments a measure of battery condition is based at least in part on at least one of first and second parameters. The first parameter is related to the decrease in battery voltage after the onset of the discharge pulse. The second parameter is related to the recovery of the battery voltage after the discharge pulse. The first and/or second parameters may be supplied as inputs to an evaluation system such as a neural network, a fuzzy logic inference engine or the like.

Abstract: A system for determining the state-of-health of batteries has an adaptive component. The system tests a battery by measuring a number of electrochemical parameters and using fuzzy logic to compute a state-of-health for the battery. The fuzzy logic computations are based upon membership functions which are preferably triangular. The membership functions may be stored in a matrix. The adaptive component adapts the system for use with new models of battery by obtaining a reliable measurement of SoH for a number of calibration batteries. Electrochemical parameters of the calibration batteries are measured. The adaptive component modifies a prototype matrix selected to match the chemistry type of the calibration batteries by scaling, translating and flexing its membership functions to achieve a matrix which specifies membership functions suitable for assessing state-of-health of the new model of battery.

Abstract: 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.

Abstract: A method for testing an electrochemical system includes obtaining complex impedance data for the electrochemical system at multiple frequencies; fitting the complex impedance data to two or more models of the system to obtain a set of fitted parameters; and deriving a value for a characteristic of the electrochemical system based upon parameters of the set of fitted parameters. The electrochemical system may be an electrochemical battery. The characteristic may be a state of health, state of charge, or other characteristic of a battery.