Abstract: A battery monitoring system (BMS), which utilizes a minimum amount of input data (time, voltage, current, temperature and conductance, for example) to periodically determine a vehicle battery status or condition is provided. The BMS combines electronic hardware and software to give logical and critical data to assess and control a battery-based electrical system. The BMS can include processing circuitry (a microprocessor, for example), which is coupled to a voltage sensor, a current sensor, a temperature sensor, etc., that provide the necessary input data for the microprocessor, which executes program code, to determine the vehicle battery status or condition. A method of monitoring a battery in an operating vehicle is also provided.

Abstract: A method and apparatus for simulating a battery tester with a fixed resistance load, such as a widely used Japanese load tester that rates the strength of Japanese batteries that are categorized under the Japanese Industrial Standard (JIS), are provided. This invention simulates such a device without invoking large current loads, yields familiar results, utilizes an existing database and provides more conclusive testing. The method includes estimating a battery load test voltage as a function of a measured battery dynamic parameter, an open circuit voltage, the load resistance value of the load tester and the battery temperature. A bounceback voltage (BBV) of the battery is also predicted. The BBV, load voltage and battery temperature are utilized to rate the strength of the battery. Also, to improve the accuracy of test results for a substantially discharged battery, one embodiment projects the results of recharging discharged batteries without actually doing so.

Abstract: A method and apparatus for testing a storage battery is provided in which a battery is measured to obtain a battery dynamic parameter value such as conductance. The battery is measured to obtain an open circuit voltage, a resistance and a recovery voltage differential. A condition of the battery is determined as a function of the measured battery dynamic parameter, the open circuit voltage and the recovery voltage differential.

Abstract: A method and apparatus for simulating a battery tester with a fixed resistance load, such as a widely used Japanese load tester that rates the strength of Japanese batteries that are categorized under the Japanese Industrial Standard (JIS), are provided. This invention simulates such a device without invoking large current loads, yields familiar results, utilizes an existing database and provides more conclusive testing. The method includes measuring an open circuit voltage (OCV), temperature and a dynamic parameter of the battery. A load voltage of the battery is estimated as a function of the measured battery dynamic parameter, the OCV, the load resistance value of the load tester and the battery temperature. A bounceback voltage (BBV) of the battery is then predicted. The BBV, the load voltage and the battery temperature are utilized to rate the strength of the battery.