Eveready Battery Company, Inc.

Moltech Power Systems, Inc.

Richard A Hudson

Syed Rahman

Thorfinn Thayer

Jai Prakash

Daniel L Killebrew

Morland J Taylor

Bobby L Tibbs

A Daniel Hall

Nate Banes

The subject invention pertains to a method and apparatus for recalibrating and/or estimating a battery's state of charge (SOC). The subject invention is advantageous in situations where the battery infrequently, if ever, reaches a full charge and/or a full discharge. In a specific embodiment, the subject method and apparatus can utilize a battery's voltage and/or current, and/or changes in a battery's voltage and/or current with time, to recalibrate and/or estimate the battery's SOC. The method and apparatus of the subject invention can monitor various parameters relating to the condition of the battery in order to determine where on the open circuit voltage (OCV) versus SOC curve, the dOCV/dSOC versus SOC curve, and/or d OCV/dSOC versus SOC curve the curve the battery is and, in a specific embodiment, when the battery reaches inflection point of the OCV versus SOC curve. Alternatively, the second derivative of the curve can be monitored to determine when the battery is outside a certain region, such as the 30% to 70% SOC region. If desired, the variation of the OCV versus SOC curve with respect to temperature and/or battery age can be taken into account during the determination of SOC in order to enhance the accuracy of such SOC determination.

Method and apparatus for battery fuel gauging

A battery pack includes a plurality of electrochemical cells and a control circuit. The battery pack provides power to a tool in the form of a pulse width modulated waveform. The plurality of electrochemical cells provide a total output voltage. The control circuit is coupled to the plurality of electrochemical cells and receives a trigger signal from the tool. In response to the trigger signal, the control circuit determines whether a pulse width of the pulse width modulated waveform requires adjustment. Additionally, the control circuit can be configured to receive an indication of the total output voltage. In this case, the control circuit determines whether the pulse width of the pulse width modulated waveform requires adjustment based on the level of the total output voltage.

Battery pack including input and output waveform modification capability

The present invention provides control bus (SMBus) management and interface for a smart battery system having an SMBus two-wire interface with a clock and data line. Electrostatic discharge protection circuitry which does not have the potential to inadvertently charge a dead battery is provided for the SMBus. SMBus mastering circuitry is also provided to work in conjunction with the SMBus interfacing routines for communications on the bus.

System and method for writing data to a serial bus from a smart battery

The subject invention pertains to a method and device for implementing a dynamic End of Discharge Voltage (EODV) for rechargeable batteries and battery packs (batteries/packs). This dynamic EODV can be adjusted based on, for example, environment, operating conditions, temperature, residual capacity, cell chemistry, cell size, form factor, discharge rate, and/or the number of charge/discharge cycles the battery has undergone. The subject invention can provide for enhanced run time from each discharge cycle of the battery/pack. In addition, the subject invention can provide for more accurate save-to-disk alarms, while ensuring adequate energy for the actual save to disk operation. Furthermore, the subject invention can also extend the useful life of the battery/pack.

Growing community of inventors

Bell, FL, United States of America

Richard A Hudson