Battery pack including input and output waveform modification capability

A battery pack for providing power to a tool in the form of a pulse width modulated waveform, comprising:

• a plurality of electrochemical cells providing a total output voltage;
• and
• a control circuit coupled to the plurality of electrochemical cells, the control circuit receiving a trigger signal from the tool, wherein the control circuit is adapted to change a pulse width of the pulse width modulated waveform in response to variations in the trigger signal, and wherein the control circuit also receives an indication of the total output voltage and is also adapted to change the pulse width of the pulse width modulated waveform in response to variations in the total output voltage, and wherein the control circuit is capable of determining the magnitude of a charging current provided by a battery charger and is also adapted to modify the charging current to provide a substantially optimal charging current for the plurality of electrochemical cells;
• and wherein the pulse width modulated waveform has a predetermined frequency in a range of about 800 Hz to 1 kHz.

A battery pack for providing power to a tool in the form of a pulse width modulated waveform, comprising:

• a plurality of electrochemical cells providing a total output voltage, wherein a number of the electrochemical cells are connected in a serial manner to form a plurality of battery sticks, and wherein a number of the battery sticks are connected in parallel to form a plurality of battery stacks, and wherein a number of the battery stacks are connected in a serial manner to provide the total output voltage;
• and
• a control circuit coupled to the plurality of electrochemical cells, the control circuit receiving a trigger signal from the tool, wherein the control circuit is adapted to change a pulse width of the pulse width modulated waveform in response to variations in the trigger signal, and wherein the control circuit also receives an indication of the total output voltage and is also adapted to change the pulse width of the pulse width modulated waveform in response to variations in the total output voltage;
• and
• at least one temperature sensor coupled to the control circuit providing a temperature indication for either at least one individual cell or at least one stick of cells, wherein the control circuit prevents a battery charger from charging the battery pack if the temperature indication falls below a first predetermined temperature.

A battery pack for supplying power to an electrical device, said battery pack comprising:

• a housing;
• a plurality of electrochemical cells disposed within said housing;
• and
• a control circuit disposed in said housing and operatively coupled to said plurality of electrochemical cells, said control circuit receiving a power demand signal from the electrical device indicating a voltage level to be supplied from the battery pack to the electrical device, said control circuit varying the voltage level output from the battery pack in response to said power demand signal, wherein said control circuit generates a pulse width modulated waveform having an average voltage per unit time that corresponds to the power demand signal from the electrical device, wherein said control circuit monitors the voltage of said cells and controls the charging and discharging of the cells in response to the voltage of the cells, and wherein said control circuit includes a switch coupled between the cells and an output terminal of the battery pack for selectively modulating the supply of power from the cells through the output terminal.

A battery pack for providing power to a tool in the form of a pulse modulated waveform, comprising:

• a plurality of electrochemical cells providing a total output voltage, wherein a number of the electrochemical cells are connected in a serial manner to form a plurality of battery sticks, and wherein a number of the battery sticks are connected in parallel to form a plurality of battery stacks, and wherein a number of battery stack are connected in a serial manner to provide the total output voltage;
• and
• a control circuit coupled to the plurality of electrochemical cells, the battery pack receiving a charging current from a battery charger, wherein the control circuit receives an indication of the charging current provided by the battery charger, and wherein the control circuit is adapted to modify the charging current to provide a substantially optimal charging current for the plurality of electrochemical cells, wherein the control circuit also receives a trigger signal from the tool and is adapted to change a pulse width of the pulse width modulated waveform in response to variations in the trigger signal, wherein the control circuit also receives an indication of the total output voltage and is also adapted to change the pulse width of the pulse width modulated waveform in response to variations in the total output voltage, and wherein the control circuit is capable of providing a voltage indicator for either at least one battery stick or at least one battery stack.

A battery pack for providing power to a tool in the form of a pulse width modulated waveform, comprising:

• a plurality of electrochemical cells providing a total output voltage, wherein a number of the electrochemical cells are connected in a serial manner to form a plurality of battery sticks, and wherein a number of the battery sticks are connected in parallel to form a plurality of battery stacks, and wherein a number of battery stack are connected in a serial manner to provide the total output voltage;
• and
• a control circuit coupled to the plurality of electrochemical cells, the battery pack receiving a charging current from a battery charger, wherein the control circuit receives an indication of the charging current provided by the battery charger, and wherein the control circuit is adapted to modify the charging current to provide a substantially optimal charging current for the plurality of electrochemical cells, wherein the control circuit also receives a trigger signal from the tool and is adapted to change a pulse width of the pulse width modulated waveform in response to variations in the trigger signal, wherein the control circuit also receives an indication of the total output voltage and is also adapted to change the pulse width of the pulse width modulated waveform in response to variations in the total output voltage;
• and
• at least one temperature sensor coupled to the control circuit providing a temperature indication for either at least one cell or at least one battery stick, wherein the control circuit prevents a battery charger from charging the battery pack if the temperature indication falls below a first predetermined temperature.