Battery charger especially useful with sterilizable, rechargeable battery packs

A method of charging a battery comprising the steps of:

• providing a charging unit with a current source capable of applying a variable charging current to the battery and a voltage measurement circuit capable of measuring the voltage across the battery;
• providing a memory that is removably attachable to the charging unit, the memory storing data indicating:
• the sequence in which the charging current is applied to the battery and the voltage across the battery is to be measured;
• the level of the current that is applied to the battery;
• and voltage set points of the voltage across the battery;
• connecting the battery to the charging unit and attaching the memory to charging unit;
• reading the data from the memory;
• and
• operating the charging unit so that:
• the current source applies current to the battery and the voltage measurement circuit selectively tests the voltage across the battery in a sequence specified by the sequence data in the memory;
• and the current source applies current to the battery based on the current level data in the memory and comparisons of the voltage across the battery with the voltage set point data in the memory.

A module for use with a battery charger, said module including:

• a shell defining a socket for receiving a battery;
• a securement mechanism attached to said shell, said securement mechanism being configured to releasably secure said shell to the battery charger;
• a plurality of conductive members attached to said shell for establishing a conductive path between the battery charger and the battery over which a charging current is applied to the battery and over which the voltage across the battery can be measured;
• a load resistor in said shell and a switch assembly in said shell for selectively connecting said load resistor across the battery;
• and
• a memory unit secured to said shell, said memory unit storing data readable by the battery charger indicating a sequence in which:
• a charging current is to be applied to the battery;
• the voltage across the battery is to be measured and;
• said load resistor is to be connected across the battery.

A charger for supplying a charging current to a battery, wherein a memory is associated with the battery that provides sequence data indicating the order in which processes are executed to charge the battery, said charger having:

• a current source configured for connection to the battery, said current source configured to generate a variable charging current to the battery based on a received CURRENT.sub.-- CONTROL signal and to provide a MEASURED.sub.-- VOLTAGE signal representative of the voltage across the battery;
• and
• a processor connected to the memory for reading the sequence data and connected to said current source for generating the CURRENT.sub.-- CONTROL signal and to receive the MEASURED.sub.-- VOLTAGE signal wherein, said processor:
• performs a plurality of different tests on the MEASURED.sub.-- VOLTAGE signal;
• generates the CURRENT.sub.-- CONTROL signal based on results of the tests performed on the MEASURED.sub.-- VOLTAGE signal;
• and perform specific MEASURED.sub.-- VOLTAGE tests and generate the CURRENT.sub.-- CONTROL signal in a specific sequence based on the sequence data read from the memory.

A method of charging a rechargeable battery, said method comprising the steps of:

• providing a rechargeable battery that is recharged by cycling the battery through a plurality of charging states;
• providing a memory that is associated with the battery, the memory storing data indicating an instruction sequence to be executed when the battery is in a specific charging state and the next charging state of the battery when the battery is in each charging state;
• providing a charger capable of supplying a charging current to the battery and measuring the voltage across the battery, wherein the charger is capable of supplying charging current to the battery and measuring the voltage across the battery in a plurality of different sequences, each different sequence being based on a different one of the instruction sequences;
• connecting the battery to the charger and reading the instruction sequence data and next charging state data from the memory into the processor;
• and
• cycling the battery through a plurality of charging states wherein the charging states through which the battery is cycled is based on the next charging state data read from the memory and, in each charging state, the charger supplies current to the battery and measures the voltage across the battery according to the instruction sequence specified for the charging state based upon the instruction sequence data for the charging state read from the memory.

A method of charging a battery comprising the steps of:

• reading data from a memory associated with the battery that defines:
• which of a plurality of different charging states through which the battery should be cycled in order to charge the battery;
• for each charging state, the current that should be applied to the battery during the charging state;
• for each charging state, a specific instruction sequence that should be executed, each instruction sequence identifying:
• the order in which the battery should be charged and at least one exit test that is performed on the battery in order to determine if the battery should exit the charging state;
• the at least one exit test that is to be performed on the battery;
• and the next charging state the battery should entry based on the results of the at the at least one exit test;
• based on the data read from the memory associated with the battery, cycling the battery through the charging states specified in the data wherein, in each charging state:
• current is selectively applied to the battery based on the current specifying data for that charging state;
• the current is applied to the battery and the at least one exit test is performed on the battery in the order identified in the instruction sequence specified for the charging state;
• the at least one exit test specified for the battery in the instruction sequence specified for the charging state is performed;
• and
• based on the results of the at least one exit test performed on the battery and the data identifying the next charging state of the battery based on the results of the at least one exit test, the battery is selectively cycled to the next charging state.

A charger for energizing a battery including:

• a current source for applying a variable charging current to the battery in response to a CURRENT.sub.-- CONTROL signal;
• a processor memory containing data defining a plurality of different instruction sequences, each instruction sequence identifying:
• the order in which the battery should be charged and at least one exit test that is performed on the battery in order to determine if the battery should exit a charging state;
• and
• the type of the at least one exit test that is to be performed on the battery;
• and
• a processor unit connected to said current source and to said processor memory, said processor unit configured to:
• read data from a memory associated with the battery that identifies:
• the charging states through which the battery should be cycled in order to charge the battery;
• for each charging state, the current that should be applied to the battery during the charging state;
• for each charging state, the specific one of the plurality of instructions sequences that should be executed when the battery is in the charging state;
• and, for each charging state, the next charging state the battery should enter based on the results of the at least one exit test;
• cycle the battery through the plurality of charging states specified by the data read from the memory associated with the battery wherein, in each charging state, said processor unit:
• and
• generates the CURRENT.sub.-- CONTROL signal to said current source to cause said current source to apply the current to the battery specified in the data read from the memory associated with the battery;
• causes said current source to apply current to the battery and performs the at least one exit test on the battery in the order specified by the instruction sequence specified for the charging state;
• performs the at least one exit test for the charging state based on the data in the instruction sequence specified for the charging state;
• and
• based on the results of the at least one exit test performed on the battery and the data indicating the next charging state of the battery read from the memory, selectively cycling the battery to the next charging state.

A module for use with a battery charger, said module including:

• a shell defining a socket for receiving a battery;
• a securement mechanism attached to said shell, said securement mechanism being configured to releasably secure said shell to the battery charger;
• a plurality of conductive members attached to said shell for establishing a conductive path between the battery charger and the battery over which a charging current is applied to the battery and over which the voltage across the battery can be measured;
• and
• a memory unit secured to said shell, said memory unit storing data readable by the battery charger indicating a sequence in which a charging current is to be applied to the battery and the voltage across the battery is to be measured, wherein the data indicates:
• specific charging states from a plurality of charging states the through which the battery should be cycled in order to charge the battery;
• for each charging state, the current that should be applied to the battery;
• for each charging state, an indication of the specific one of a plurality of instruction sequences that should be executed, each instruction sequence identifying:
• the order in which the battery should be charged and at least one exit test that is performed on the battery in order to determine if the battery should exit the charging state;
• the at least one exit test is performed on the battery to determine if the battery should exit the charging state;
• and
• for each charging state, the next charging state the battery should enter based on the result of the at least one exit test.

A rechargeable battery pack comprising:

• a housing;
• at least one rechargeable cell disposed in said housing;
• a first set of terminals attached to said housing that are attached to said at least one rechargeable cell, wherein energy is applied to said first set terminals for storage in said at least one rechargeable cell and current is drawn from said at least one rechargeable cell through said first set terminals;
• a memory disposed in said housing, said memory including data readable by a battery charger indicating a sequence in which a charging current is to be applied to the battery and the voltage across the battery is to be measured, wherein the data indicates:
• specific charging states from a plurality of charging states the through which the battery should be cycled in order to charge the battery;
• for each charging state, the current that should be applied to the battery;
• for each charging state, an indication of the specific one of a plurality of instruction sequences that should be executed, each instruction sequence identifying:
• the order in which the battery should be charged and at least one exit test is performed on the battery in order to determine if the battery should exit the charging state;
• the at least one exit test that is performed on the battery to determine if the battery should exit the charging state;
• and
• for each charging state, the next charging state the battery should enter based on the result of the at least one exit test;
• a second set of terminals attached to said housing and connected to said memory, wherein the data are read from said memory over the second set of terminals.