Abstract: A cutoff switch (40) separates the reference line (20) of a control circuit (18) from the B- line (24). The cutoff switch is in an electrically open state until the function of the control circuit is required, thus eliminating current flow through the control circuit when the function of the control circuit is not required. To enable the control circuit, a threshold switch (42) is provided to cause the cutoff switch to change states when the battery voltage reaches a predetermined level. To provide an override, a diode is connected between an auxiliary line (26), used a thermistor (28), for example.

Abstract: A lithium ion or similar lithium secondary battery pack (10) includes an overvoltage disconnect circuit having an overvoltage disconnect switch (14), a voltage detector (16), and a delay circuit (18). The battery pack is connectable to a recharger which was not designed to accomodate the charge regime of the lithium ion cell or cells (12), such as a nickel system recharger (20). The voltage detector samples the battery voltage and changes its output signal if the battery voltage reaches an upper voltage threshold. The output of the voltage detector will not revert back until the battery voltage drops to a lower voltage threshold, which is below the upper voltage threshold.

Abstract: A thermal sensing polymeric device (110) such as a capacitor is fabricated from a layer of a copolymeric material (112) including polyvinylidene fluoride and a fluorinated ethylene. The fluorinated ethylene may be selected from the group including trifluoroethylene and tetrafluoroethylene. The thermal sensing polymeric device may be a capacitor fabricated of polyvinylidene fluoride-trifluoroethylene copolymeric material. In such an application, the capacitor device exhibits a change in capacitance as the temperature to which the device is exposed is changed. Specifically, as the temperature of the polymeric material crosses a threshold transition temperature, a substantial change in its capacitance is observed.

Abstract: A device (111) for simulating a high battery temperature used in charging a rechargeable cell (101). The device takes advantage of a control signal generated by a voltage control circuit (103) used to disconnect a rechargeable cell (101) from a charging system (105) when a predetermined voltage is reached. The device (111) is generally used with cells having a lithium based chemistry and requiring a different charging regime then nickel chemistry cells. The device (111) is activated by the control signal from control circuit (103) which detects a predetermined voltage from rechargeable cell (101) enabling thermistor (113) to change its state. This change is detected by the charging system (105) which alters its mode of operation from a rapid charging rate to a slower charging rate. The device is retrofitable to existing rechargeable batteries allowing them to be charged using existing charging systems alien to the rechargeable battery.

Abstract: A battery recharge current source 12 provides a recharge current 14 to battery cells 16. Recharge current 14 is in excess of an optimum recharge current level for battery cells 16 and is divided into currents 26 and 28 by variable shunt load 24 as controlled by charge current control circuit 18. Charge current control circuit 18 is comprised of current sense circuit 20 and load control circuit 22. Current sense circuit 20 produces a current sense signal in response to current through battery cells 16. Load control circuit 22 is responsive to the current sense signal and controls variable shunt load 24 as needed to conduct excess current away from the battery cells.

Abstract: A battery pack (62) comprises cells (74), and is charged by a charger (64) providing a current level. The charger (64) is a typical nickel-cadmium battery charger providing a first charge current level in excess of an optimum charge current level. The battery pack (62) further comprises a thermal sensing element (76) and an overcurrent charge protection circuit having an overcurrent switch (78), current sense circuit (80), comparator circuit (82), and temperature signal switch (84). If the current level through the cells (74) exceeds the optimum charge current level, the current sense circuit (80) provides a signal to comparator circuit (82) which actuates the temperature signal switch (84), simulating a hot battery pack. The charger (64) then switches to a second charge current level which does not exceed the optimum charge current level.

Abstract: A battery system (400) for use with portable electronic products which includes protection circuitry for allowing the battery system to be safely recharged in a recharging system. The battery system (400) includes cells (401) and a plurality of controls including and overcharge protection circuit (433) for limiting the amount of current to the cells (401) by a charging network and a thermistor (415) and thermistor control (417) for controlling the state of the thermistor (415) to simulate a high temperature condition allowing the charging network to switch modes and accommodate battery system (400) which does not following the charging regimen provided by charging system.

Abstract: A battery pack (10) having a protruding battery contact (14) is provided with a disconnect switch circuit. The circuit comprises at least one battery cell (22), and a mechanical switch (24) which controls .ang.operation of an electronic switch circuit (36). A latch member (16) is provided for attaching the battery pack to a device to be powered, and is moveable between a first and second position, and is biased by a spring means to the first position. In the first position, the latch member acts on the mechanical switch such that the electronic switch circuit disconnects the battery contact from the battery cell or cells. When the latch member is moved to the second position (17), the circuit operates to connect the battery contact to the battery cell or cells.

Abstract: A battery charging system (200) comprises a battery pack (206) and charger (202). Battery pack 206 includes a thermistor (212) for determining the temperature of battery pack (206) and a zener diode (210)in parallel with the thermistor (212) for informing charger (202) of the current capacity of battery (206) or of another battery parameter. Charger (202) includes a transistor (220) and zener diode (214) for effectively switching between measuring thermistor (212) and zener diode (210) at charger input terminal (224). This effectively reduces the number of battery and charger contacts required to measure two battery parameters as compared to the prior art.

Abstract: A battery pack (10) includes at least one battery cell (16) and a current interrupt device (18) adapted to protect said cells from damage during charging or discharge. The battery pack (10) is further adapted to be recharged at extremely fast recharge rates via the use of a bypass switch (20) which allows current to be diverted around current interrupt device (18) during recharge. The bypass switch (20) is controlled by a control circuit (22) which provides a control signal and response to sensing a charge current.

Abstract: A modular battery pack (10) is described having several embodiments. In general, the modular battery pack has a battery cell cartridge (12), a circuit cartridge (14), and a housing (16). In conventional battery packs these three elements are combined into one single unit. The invention modularizes these components such that portions may be re-used and shared. This results in a more cost effective power system for a portable electrical or electronic device (40) since, once the battery cell or cells (48) have expired, they can be replaced without having to replace the other components, in particular the circuitry.

Abstract: An undervoltage recovery pulse network (500) and method used with a lithium ion battery system (400) for providing a initiation voltage to a battery controller (503) which has been operationally disabled due to an event associated with the lithium ion battery system (400). The undervoltage recovery pulse network (500) includes a switch (523) for detecting a first voltage applied to a data terminal (537) by a charging system. A coupler (525) is used for supplying a second voltage from a charging terminal (535) to the battery controller (503) to enable the battery controller from its disabled state. The battery controller (503) then connects the voltage potential of a cell (501) to the charging terminal (535) for detection by a charging system. This allows the charging system to detect an attached battery so it may apply a charging voltage to charging terminal (535).

Abstract: A method (200) of charging a multiple voltage battery is disclosed. The multiple voltage battery is characterized by a preselected operating voltage and a charge profile curve having at least two occurrences of the slope thereof being substantially zero. The number of occurrences of the slope of the charge profile curve being substantially zero corresponds to the number of voltage levels the cell is adapted to operate in. The method recognizes the signature charging profile of the multiple voltage level battery and is thus capable of terminating battery charge at the level corresponding to the preselected operating voltage.

Abstract: A battery pack 12 for powering a device 14 sensitive to input voltage contains a protection switch 28 and a control circuit 26. When the battery pack 12 is charged by a charger 10 and the voltage of the battery pack approaches the maximum safe level of the device 14, the control circuit 26 causes the protection switch 28 to electrically switch open to protect the device 14 from excessive voltage potentially output by the charger. Where the cells 16 are lithium ion cells or a type having a maximum safe voltage, a safety switch 49 is included to interrupt charge current 52 through the cells 16. The safety switch 49 is delayed by resistor/capacitor network 51, 53 so that it switches after the protection switch 28. The safety switch 49 includes a diode 58 to allow the device 14 to remain powered while the safety switch is blocking charge current. Further, diodes 40 and 42 are required to eliminate measurement error of the control circuit 26 if the battery pack 12 is charged through the device contacts 20 and 24.

Abstract: A battery charger system (100) is provided which includes a charger (110) for supplying charge current and voltage and a battery (120) having a memory (122) for storing charge parameters. The charge parameters comprise battery related information instructing for battery charging. The battery related information stored in the memory (122) may include charge instructions instructing the charger of procedure for charging the battery (122).

Abstract: A modular battery pack (10) is described having several embodiments. In general, the modular battery pack has a battery cell cartridge (12), a circuit cartridge (14), and a housing (16). In conventional battery packs these three elements are combined into one single unit. The invention modularizes these components such that portions may be reused and shared. This results in a more cost effective power system for a portable electrical or electronic device (40) since, once the battery cell or cells (48) have expired, they can be replaced without having to replace the other components, in particular the circuitry.

Abstract: A battery (200) includes a device (201) used for simulating a high temperature condition of a thermistor (216) located in battery (200). The battery (200) includes a charging node (203), temperature node (205) and ground node (207). A control circuit (209) is used with lithium ion cell (211) to measure voltage of lithium ion cell (211). Control circuit (209) produces a control signal when a desired voltage is reached during recharging. The control signal works with a high voltage switch (217), thermistor (216), diode (213) and resister (215) to control the voltage on temperature node (205). Any change in voltage on temperature node (205) may then be detected by an attached charging system to allow it to change its mode of operation.

Abstract: A battery charging system (10) includes a charger (12), power supply (14), electrical device (16), external battery (18), and peripheral device (20). The charger (12) provides connections between the various components such that the electrical device (16), which is a portable electronic device, may communicate with the peripheral device (20). The components are kept small by providing the power supply (14) with a feedback input (26). The power supply generates a voltage output (24) which is at a preselected differential above the feedback level, thus minimizing overhead voltage levels and allowing efficient linear regulation in the electrical device (16) for battery recharging.

Abstract: A battery assembly (200) includes first and second battery housings (202 and 204), a plurality of battery cells (204), and a flexible circuit having a thermal sensing surface (206) which is located in thermal proximity to battery cells (204). The thermal sensing surface (206) is in thermal proximity to the plurality of battery cells (204) providing for improved thermal sensing of battery assembly (200).

Abstract: A rechargeable battery (100) includes a lockout circuit (200) for preventing rechargeable cells (101) from being charged when connected to a charging system (103) which does not include a data node (109). The lockout circuit (200) includes a lockout switch (113) which is biased by a voltage applied to data node (109). Data node (109) provides a closed circuit to allow rechargeable cells (101) to be charged only with charging systems which utilize a correct charging regimen.