Motorola Corporation

Iilonga P Thandiwe

James L Estes, Jr

Vernon Meadows

Jose M Fernandez

Steven R Fischl

Brian Thomas Pozsgay

Erika D Mack

Sarah A Peek

Ron Torrence

Theresa P Szeto

A circuit and method are disclosed for pulse charging a battery. In this method, the duration of the charging interval of the pulse is governed by the time required to reach an upper threshold voltage. The duration of the non-charging interval is a function of the ionic relaxation of the battery. One preferred embodiment includes a method in which the charging interval is initiated at a voltage that corresponds to the current state of charge of the cell. For example, when the upper threshold is reached, charging is suspended. A microprocessor then determines the state of charge by way of a fuel gauge. If a cell is 70% charged, for instance, an on voltage corresponding to this state of charge is selected. When the cell reaches the on voltage, the charging interval is again initiated. Other alternatives to this method include sensing a slope to determine when ionic relaxation has occurred, and a mathematical approximation of the method.

Pulse charging circuit and method

This invention includes a power management method and apparatus for portable electronic devices, like cellular phones for example, to which accessories may be attached. These accessories include MP-3 players, personal digital assistants, and pagers. In a simple embodiment, a battery pack having a fuel gauge and power management controller measure an energy profile required by the host. From this profile the power management controller can determine when accessories are attached to the host by the amount of power being drawn. When the capacity of the cell is reduced below a predetermined threshold, the power management controller notifies the user that a limited amount of operational time remains and accessories should be turned off. In another embodiment, the power management controller automatically allocates power between the host and accessories once the predetermined threshold has been reached.

Battery with embedded power management

A smart battery that has a network communication interface such that the battery can send and receive battery-related data. The battery is in conductive and communicative interface with a device, such as a cellular telephone, personal digital assistant (PDA), or laptop computer, which has a network communication pathway that the battery uses for data exchange. The smart battery can alternately be in conductive and communicative interface with a charger that is interfaced with a computer, and the charger selectively establishes a network communication pathway through the charger-computer interface for the smart battery to exchange data across the network. The smart battery preferably exchanges data with a manufacturer web site across the Internet.

Battery having a network communication interface

A method for testing safety circuitry in rechargeable battery packs is provided herein by which the operation and integrity of circuits associated with rechargeable cells may be verified. A controller,senses current flow during cell,charge or discharge. The controller,then activates the safety circuitry and once again senses current to ensure high circuit impedance. If a fault is detected, the controller,notifies the user or host device. The controller,then decides if the fault warrants isolating the cell,from the terminals of the battery pack,If such action is warranted, the controller,clears the current carrying path,creating a fail condition that does not endanger the user or associated equipment.

Method for Li-Ion safety switch fault detection in smart batteries

A cell current limiting circuit includes a current-limiting device that electrically couples a cell to a battery terminal. A bypass current path is in parallel with the current limiting device and is selectively interruptible by a switch. A switch control circuit is capable of sensing if the battery terminal is electrically coupled to a selected host. The switch control circuit closes the switch if the battery terminal is electrically coupled to the selected host and opens the switch if the battery terminal is not electrically coupled to the host.

Variable on demand energy source

This invention is a system and method for causing a rechargeable battery pack to enter a low power mode. The system includes a resistive divider, a switch, a battery cell, and a safety integrated circuit. When an external voltage is applied to the resistive divider, the switch turns on. With the switch on, the safety integrated circuit senses only a fraction of the cell voltage and therefore puts the battery pack into a low power, or sleep mode. The battery is returned to normal mode by connecting a charger to the battery pack.

Low power enable circuit

A battery pack (100) includes a battery cell (102), a power switch (104), a regulator circuit (106), control circuit (108), electronic drive switch (112), and a mechanical driver switch (116). The battery pack is placed in the hibernate mode by sending a hibernate message to the control circuit from an external device (134). The control circuit removes a control signal from the electronic driver switch, causing the power switch to open, removing power from the regulator circuit and all attached circuitry, including the control circuit. No current flows from the battery cell past the opened power switch, and the battery pack is then in the hibernate mode. To wake up the battery pack, the mechanical driver switch is actuated by a user, causing the power switch to close, allowing current and voltage from the battery cell to power up the regulator circuit, which in turn powers up the control circuit. The control circuit applies a control signal to the electronic driver switch to hold the power switch closed.

Battery pack having a hibernate circuit

A battery (104) is connected to a host device (106), the host device is an electrical or electronic device, such as a cellular telephone. The battery is rechargeable, and contains a memory (110) connected to a data line (116). The battery is connected to a battery charger (102) while also connected to the host device. The battery charger detects the battery (306), reads the battery information (308) from the battery memory. The data line is common to the battery charger, battery, and host device. The charger indicates its presence to the host device by changing the voltage level on the data line (310) from a normal first level, such as a logic level of one, to a second level, such as a logic level of zero, and holds the data line at the second level. The host detects the presence of the battery charger (312) after the data line has been held at the second level for a sufficient period of time, and then may take the desired actions (314).

Method for an electronic device to detect the presence of a battery

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. If the charger (64) does not change current levels, a switch delay (86), after a brief period, accumulates enough voltage to actuate a driver switch (88) which opens the overcurrent switch (78), disconnecting the cells (74) from the charger (64).

Overcharge current protection circuit and battery pack using same

A battery pack (10) has a memory (26) for storing a password. Upon connecting to a host device (12), or similar load, the battery waits for a data word to be communicated from the host device over a communications channel (22). If an incorrect data word is received a predetermined number of time, or if an initial power time period, as defined by a timer (30), is reached, a switch (16) is opened, thereby disconnecting the battery cell or cells (14) from the load.

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Atlanta, GA, United States of America

Iilonga P Thandiwe