A battery module having a housing (15) including a plurality of cavities (16), each receiving a housing-element assembly (1) having: a) an electrochemical element (2) with a cylindrical container and two current output terminals (3, 4) disposed on a wall of one of the ends of the container, at least one of the two current output terminals being electrically connected to an electrical connection bar (5); b) a housing (6) in the form of a tube for receiving the electrochemical element, the housing electrically insulating the electrochemical element and having one or more indexing members (7, 8); c) a housing cover (9) provided with a means (10) for causing the electrochemical element to rotate about its longitudinal axis.

A power tool is provided with a multi-phase brushless motor including a rotor and a stator having stator windings corresponding to at least three phases of the motor. A power switch circuit is provided including high-side and low-side power switches. A power supply interface receives alternating-current (AC) power from an AC power supply or battery direct-current (DC) power from one or more battery packs. A rectifier converts the AC power to a rectified DC voltage on a bus line. A capacitor is disposed across the bus line such that, within each half cycle of the AC power voltage waveform, the power switch circuit draws current from the AC power supply within a first time period and from the capacitor within a second time period, the capacitor having a capacitance value such that the first time period is greater than the second time period.

A power tool is provided including a power supply interface receiving a medium-voltage-rated removable battery pack having a maximum rated voltage in the range of 40 to 80 volts, and a brushless direct current (BLDC) motor. The motor includes a rotor and a stator having at least three stator windings corresponding to at least three phases of the motor, the rotor being moveable by the stator when the stator windings are appropriately energized within the corresponding phases, each phase being characterized by a corresponding voltage waveform energizing the corresponding stator winding. A multi-phase inverter bridge circuit is disposed between the power supply interface and the motor, and a controller is configured to output drive signals to the inverter bridge circuit to control flow of current from the battery pack to the motor such that the motor produces a maximum power output of at least 2500 watts.

A method of operating a medical device comprises electrically connecting a power device to the medical device. The method further comprises sensing at least one characteristic of one of the medical device with the power device. The method further comprises adjusting or maintaining one or more characteristics of an electrical connection feature the power device according to the at least one observed characteristic such that the electrical connection features of the power device and medical device are operationally compatible, and operating the power device according to an operational profile associated with the medical device.

A method of operating a medical device comprises electrically connecting a power device to the medical device. The method further comprises sensing at least one characteristic of one of the medical device with the power device. The method further comprises adjusting or maintaining one or more characteristics of an electrical connection feature the power device according to the at least one observed characteristic such that the electrical connection features of the power device and medical device are operationally compatible, and operating the power device according to an operational profile associated with the medical device.

A method of operating a medical device comprises electrically connecting a power device to the medical device. The method further comprises sensing at least one characteristic of one of the medical device with the power device. The method further comprises adjusting or maintaining one or more characteristics of an electrical connection feature the power device according to the at least one observed characteristic such that the electrical connection features of the power device and medical device are operationally compatible, and operating the power device according to an operational profile associated with the medical device.

A method of operating a medical device comprises electrically connecting a power device to the medical device. The method further comprises sensing at least one characteristic of one of the medical device with the power device. The method further comprises adjusting or maintaining one or more characteristics of an electrical connection feature the power device according to the at least one observed characteristic such that the electrical connection features of the power device and medical device are operationally compatible, and operating the power device according to an operational profile associated with the medical device.

A method of operating a medical device comprises electrically connecting a power device to the medical device. The method further comprises sensing at least one characteristic of the medical device with the power device. The method further comprises adjusting or maintaining one or more characteristics of an electrical connection feature of the power device according to the at least one observed characteristic such that the electrical connection feature of the power device is operationally compatible with an electrical connection feature of the medical device. The method further comprises operating the power device according to an operational profile associated with the medical device.

A method of operating a medical device comprises electrically connecting a power device to the medical device. The method further comprises sensing at least one characteristic of the medical device with the power device. The method further comprises adjusting or maintaining one or more characteristics of an electrical connection feature of the power device according to the at least one observed characteristic such that the electrical connection feature of the power device is operationally compatible with an electrical connection feature of the medical device. The method further comprises operating the power device according to an operational profile associated with the medical device.

A battery pack and charger system includes a first battery pack having a first set of battery cells and configured to provide only a first operating voltage and a second battery pack having a second set of battery cells and configured to provide the first operating voltage and a second operating voltage that is different from the first operating voltage and a battery pack charger configured to be able to charge the first battery pack and the second battery pack.