Abstract: The invention relates to a power management system for supplying backup DC power to peak and/or high current demand battery applications, such as motor starting or an uninterruptible power supply (UPS) used to power a critical load, such as, a data bus or other critical load, after an event, such as loss of primary AC or DC input, during relatively cold ambient temperatures. Two or more heaters can be provided; for example, a low power heater and a high-power heater. In a maintenance mode, the low power heater is used to maintain batteries at a predetermined temperature. In this mode, a battery charger is used to power the low power heater. In a boost mode, after the primary AC or DC input is restored, and battery temperature is too low to back up the critical load, the battery charger supplies power to one or both of the heaters.

Abstract: A power management system is disclosed for providing an indication of the required available capacity (RAC) available from a backup battery unit (BBU) for backup or peak loading as required by a critical DC load, such as a computer bus. The power management system is configured to repeatedly determine the gross remaining capacity of the backup battery unit (BBU). The system processes this information and other measured or known battery parameters to determine the required available capacity (RAC). The RAC is based upon the required capacity of the critical load to which the BBU is connected. In general, the RAC is the difference between the gross remaining capacity of the battery at a given point in time and the required capacity of the critical load. In accordance with an important feature of the power management system, an indication of the RAC is provided.

Abstract: Briefly, the present invention relates to a cigarette lighter adapter (CLA) configured to be received in a CLA socket in a vehicle. The CLA includes a positive contact and a negative contact and housing, for example, a plastic housing. The negative contacts are formed as springs, which extend from the housing and are configured to exert spring force against an interior wall of a socket to assure a solid connection. The positive contact is also formed as a spring and is connected in series with a thermal sensor. In accordance with an important aspect of the invention, the thermal sensor, for example, a bi-metallic strip, is in thermal contact with a tip, which is serially connected to the positive contact and which extends outwardly from the plastic housing, the thermal sensor causes the CLA to be disconnected from the socket when an excessive temperature is sensed.

Abstract: A multiple cell battery charger with a parallel topography is disclosed which requires fewer active components than known battery chargers and protects the battery cells from overcharge and discharge. The charger that includes a regulator for providing a regulated source of direct current (DC) voltage to the battery cells to be charged. Each battery cell is connected in series with a switching device, such as a field effect transistor (FET) and optionally a current sensing device. In a charging mode, the serially connected FET conducts, thus enabling the battery cell to be charged. Battery voltage is sensed by a microprocessor. When the microprocessor senses that the battery cell is fully charged, the FET is turned off, thus disconnecting the battery cell from the circuit. Since the battery cell is disconnected from the circuit, no additional active devices are required to protect the battery cell from discharge.

Abstract: A multiple cell battery charger configured with a parallel topography is disclosed. In accordance with an important aspect of the invention, the multiple cell battery charger requires fewer active components than known battery chargers while at the same time protecting multiple battery cells from overcharge and discharge. The multiple cell battery charger in accordance with the present invention is a constant voltage battery charger that includes a regulator for providing a regulated source of direct current (DC) voltage to the battery cells to be charged. In accordance with the present invention, each battery cell is connected in series with a switching device, such as a field effect transistor (FET) and optionally a current sensing device. In a charging mode, the serially connected FET conducts, thus enabling the battery cell to be charged. The battery voltage is sensed by a microprocessor.

Abstract: A multiple cell battery charger configured with a parallel topography is disclosed. In accordance with an important aspect of the invention, the multiple cell battery charger requires fewer active components than known battery chargers while at the same time protecting multiple battery cells from overcharge and discharge. The multiple cell battery charger in accordance with the present invention is a constant voltage battery charger that includes a regulator for providing a regulated source of direct current (DC) voltage to the battery cells to be charged. In accordance with the present invention, each battery cell is connected in series with a switching device, such as a field effect transistor (FET) and optionally a current sensing device. In a charging mode, the serially connected FET conducts, thus enabling the battery cell to be charged. The battery voltage is sensed by a microprocessor.

Abstract: A rapid charging circuit for a lithium ion battery. The battery charger in accordance with the present invention compensates for the voltage drops across the various resistance elements in the battery circuit by setting the charging voltage to a level to compensate for the initial resistance of the series resistances in the circuit and an additional resistance selected to take into account the anticipated increase in resistance of the various circuit elements over time. The battery charger in accordance with the present invention periodically monitors the open-circuit voltage of the battery cell and reduces the charging voltage to when the battery cell voltage reaches the optimal value. Thus, during a constant current charging mode, the battery cell is driven at a relatively optimal charging current to reduce the charging time.