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: Two-way voltage switching may be performed using a single switch mode regulator circuit such that only control signals and feedback signals are used to select the direction of the power path. Such voltage switching may be between a battery and a supply rail that operate at different voltage levels. The voltage level of the battery's output may be converted by the regulator to the voltage level of the supply rail such that at least a portion of the power drawn by the system from the supply rail is from the rechargeable battery. To charge the rechargeable battery from the supply rail, the voltage of the supply rail may be converted to the voltage level of the battery using the same switch mode regulator. To select between discharging the battery into the supply rail or charging the battery from the supply rail, no power path circuitry need be switched.

Abstract: Various embodiments disclose methods and systems for controlling operation of a regulator controller integrated circuit. The regulator controller integrated circuit may include a run input and a voltage supply input. A voltage supply, having an on state and an off state, may be coupled with the voltage supply input of the regulator controller integrated circuit. A JFET that has a source, a drain, and a gate may be present. The source of the JFET may be coupled with electrical ground. The drain of the JFET may be coupled with the run input of the regulator controller integrated circuit. The gate of the JFET may be coupled with the voltage supply. Such embodiments may disable a regulator unless a supply voltage is present without requiring a supply voltage for control circuitry.

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.

Abstract: The present invention discloses a battery charger and a method for charging a plurality of batteries. The battery charger includes: a current source for supplying a source current which has a charge current portion and a diverted current portion; bypass sections; voltage clamp sections; sense sections; a feedback section for processing information from the sense sections; and a controller for modifying the source current based on the information from the feedback section. Each bypass section is connected to a battery for diverting the diverted current. Each voltage clamp section is connected to the bypass section for clamping a voltage across the battery when the voltage increases to a predetermined level. Each sense section is connected to the bypass section for determining the diverted current and/or the charge current.

Abstract: The present invention provides a protection circuit and method for preventing a battery from swelling in one embodiment. The protection circuit includes: a voltage monitoring circuit that monitors a voltage across the battery; a control circuit that receives voltage information from the voltage monitoring circuit; and a discharge circuit that turns on to discharge the battery upon receiving a signal from the control circuit.

Abstract: The present invention relates to a battery protection circuit for protecting a plurality of batteries connected in series. The battery protection circuit includes: a controller for monitoring the batteries and outputting control signals based on predetermined conditions associated with the batteries; a first N-channel MOSFET and a second N-channel MOSFET coupled in a common-drain configuration in a low-side path, wherein at least one of the first and second N-channel MOSFETs turns off in response to the control signal received from the controller when at least one of the predetermined conditions is detected; and a gate protection circuit for preventing gate-to-source voltages of the first and second N-channel MOSFETs from exceeding a predetermined gate-to-source voltage level.

Abstract: According to the invention, an apparatus for robust battery discharge which provides uninterrupted power to a discharge circuit used in a discharge cycle is disclosed. The apparatus may have a discharge circuit for discharging a battery. The discharge circuit may be adapted to be coupled with a discharge load and configured to discharge the battery using the discharge load during a discharging cycle. The apparatus may have a first power input and a second power input, which may configured to receive power from a first power source and a second power source, respectively. The power inputs may be further configured to supply power to the discharge circuit. The apparatus may have a power switching circuit for switching power from the first power source to the second power source when the first power source is interrupted. The second power source may be the battery.