Abstract: Deficiencies in the electrolyte level of the cells of NiCd battery can be detected by measuring the internal resistance of the cells. Initially, data is collected for a battery type and capacity, correlating measured internal resistance with the amount of water that must be added to bring the cell resistance to an acceptable value. Subsequently, cells of other batteries of the same type and capacity can be measured to determine how much water must be added and the levels quickly restored. The polarization value of the cells can be used lieu of the internal resistance in the same fashion.

Abstract: Apparatus and method for automatic recovery of sulfated lead acid batteries rely on monitoring battery voltage, current and internal resistance during battery charging. The lead acid battery is recovered for usage by measuring the internal resistance to see if it is so high such that the battery is unrecoverable, or so low such that the normal charging methods can be used. If the internal resistance is between the two limits, the battery receives a first constant charge current. As the lead acid battery is being charged slowly by a constant charge current, the battery voltage is measured. The decrease in the internal resistance (IR) of the battery causes the battery voltage to decrease during charging, while the charging causes the battery voltage to increase. According to the present invention, if it is detected that the battery voltage has reached the minimum voltage and begun to increase in a predetermined period of time, the charge current is substantially increased (e.g.

Abstract: A method and apparatus for diagnosing the status of a battery having high and low voltage plateau states corresponding to its state of charge in which the battery open circuit voltage is measured (S106) to determine its voltage state and its internal resistance also is measured (S114). A battery having a low voltage state (S116) is tested to determine if its internal resistance is greater than a predetermined maximum resistance (S118) and if it does the battery is considered as possibly having a low electrolyte level, and if it does not the battery is subjected to a current ramp test to determine from the voltage response a point of current transition (S130) due to a battery chemical gassing reaction. The battery state of charge (S132) is determined from curves or algorithms of state of charge versus current transition.

Abstract: A method and apparatus for monitoring and maintaining a plurality of batteries. The batteries are maintained according to a two-part method. In the first part, a normal analysis is performed on all of the batteries. In the normal analysis, it is determined if any one of the batteries has marginal conditions. The marginal battery (which can be one or more batteries) is selected for a second part of the method, which includes a detailed analysis. The detailed analysis is performed on the marginal battery. The marginal battery is then serviced according to the results of the detailed analysis.

Abstract: The invention provides a method and apparatus for controlling an alternator (605) by turning it ON or OFF depending upon the battery conditions and the operating conditions of the automobile monitored by various sensors (606, 609 and 611). By allowing the batteries of the automobile (610), controlled by a battery control unit (608), to charge and discharge based on its state of charge (SOC), the load imposed by the alternator (605) can be reduced such that the fuel efficiency of the automobile is optimized. By setting SOC limits, the alternator (605) can be turned ON or OFF, using an alternator control unit (604), depending on whether the SOC of the batteries is within the SOC limits. In addition, power loading limits can be preset so that the alternator (605) can be turned ON or OFF depending on the power loading conditions. The alternator (605) may be turned ON or OFF, using an alternator control unit (604), based on other conditions as well.

Abstract: A system and method for comprehensive analysis of a multi-cell battery, such as of the nickel-cadmium type, on an individual cell level basis and overall battery basis. For an unsealed battery, which affords access to the individual battery cells, (FIG. 2) tests are carried out to determine the presence of any shorted or reversed cells, and these can be repaired or replaced ((6)-(11)). The individual cells are then tested for sufficient electrolyte on the basis of comparing the cell internal resistance to a maximum internal resistance for the cell and electrolyte added as needed ((12)-(15)). A sealed battery, to which there is no access to the individual cells, is first tested for shorted or reversed cells on a battery level basis ((16)-(19)).

Abstract: The invention provides for a timesaving method of determining whether a nickel cadmium (NiCd) battery is stricken with memory effect. A fully charged NiCd battery under test ("test battery") is subjected to a positive sloped current charge ramp and then a negative sloped current charge ramp while continuously monitoring the battery terminal voltage. The maximum measured terminal voltage of the test battery is compared to the measured terminal voltage of a NiCd battery of the same nominal voltage and capacity and known not to have memory effect ("normal"battery). A NiCd battery is determined to have memory effect if the maximum voltage of the test battery exceeds the maximum voltage of the normal battery.

Abstract: The invention provides for a timesaving method of determining the capacity of a nickel cadmium (NiCd). A fully charged NiCd battery under is subjected to a positive sloped current charge ramp and then a negative sloped current charge ramp while continuously monitoring the battery terminal voltage. The voltage is plotted and the maximum slope of the measured terminal voltage determines l.sub.gas. The value of I.sub.gas is compared to a temperature calibration curve to determine the capacity of the battery under test.