Abstract: A compact battery pack with high handling ability and restraining degradation of battery cells. The battery pack includes an insertion portion to be inserted into a handle portion of a cordless power tool and an accommodation portion in which all battery cells are accommodatable. A protection board with a protection circuit that protects batteries against overcharge and over-discharge is installed in the insertion portion. A switching element is connected between the battery cells and a drive motor of the power tool. An air passage in communication with the battery pack is formed within the handle and a main housing of the cordless power tool. The switching element is positioned at the air passage.

Abstract: A setting current switching circuit 120 includes a comparator 127. A battery temperature signal corresponding to a battery temperature detected by a battery temperature detecting unit 8 is inputted to one input terminal (?) of the comparator 127 and a reference signal corresponding to a reference temperature is inputted to the other input terminal (+) of the comparator 127 to vary the setting charging current value of a charging current setting unit 80 and the setting full-charge current value of a full-charge current setting unit 90 correspondingly to the output of the comparator 127.

Abstract: An electrical power tool includes a housing, an electrical motor, an end-bit holding section, a transmitting mechanism, a cap, and a lighting section. The housing has one end. The electrical motor is accommodated in the housing and is configured to generate a rotational driving force. The end-bit holding section is provided at the one end and is rotatable about a rotational axis. The transmitting mechanism transmits the rotational driving force to the end-bit holding section. The cap is attached to the one end. The lighting section allows an entirety of the cap to be luminous.

Abstract: To prevent a battery pack from being over-discharged even under a state that the battery pack (a secondary battery) is connected to a discharging device that is not connected to an ac input power source for a long time. A charging device has a pair of output lines and an anode terminal and a cathode terminal of a secondary battery electrically connected between the output lines to carry out a charging operation. In the charging device including a component circuit part electrically connected by traversing a part between the pair of output lines, a switching element is inserted between the component circuit part and one of the pair of output lines. When the charging device is not connected to an input power source, the switching element is allowed to be non-conductive to interrupt a discharging path so that the component circuit part does not form the discharging path.

Abstract: A charging voltage or an overcharge determination value for determining an overcharge state is set taking into consideration the states of secondary battery cells of a battery pack during charging. Charging of the secondary battery cells is then carried out using charging voltages set taking into consideration the states of the secondary battery cells. It is then determined whether or not the secondary battery cells are in an overcharged state using overcharge determination value is set taking into consideration the states of the secondary battery cells.

Abstract: A compact battery pack with high handling ability and restraining degradation of battery cells. The battery pack includes an insertion portion to be inserted into a handle portion of a cordless power tool and an accommodation portion in which all battery cells are accommodatable. A protection board with a protection circuit that protects batteries against overcharge and over-discharge is installed in the insertion portion. A switching element is connected between the battery cells and a drive motor of the power tool. An air passage in communication with the battery pack is formed within the handle and a main housing of the cordless power tool. The switching element is positioned at the air passage.

Abstract: A charging apparatus able to safely and reliably secure capacity is provided. The charging apparatus comprises: a charging current configuration unit that configures a set value for the charging current flowing to the battery; a charging current controller that controls the charging current on the basis of the set value configured by the charging current configuration unit; a cell voltage detector that detects the cell voltages applied to each cell; and a voltage determining unit that determines whether or not at least one of the cell voltages detected by the cell voltage detector has exceeded a threshold voltage. If it is determined by the voltage determining unit that at least one of the cell voltages has exceeded the threshold voltage, then the charging current configuration unit switches the set value to a smaller value.

Abstract: A battery charger has an abnormal condition checking function for checking unintentional or accidental charging of a secondary battery. A charge circuit charges the battery when a switching element interposed between a power source and the battery is turned on. Current which may flow in the charge circuit is detected when the battery is not to be charged by turning the switching element on. When the current is detected in such a condition, an abnormality signal is produced to cause the charge circuit to be disabled.

Abstract: A solar power system has a charging device. The charging device is powered by a solar cell to charge a battery pack having a secondary cell. The charging device has input voltage detection circuit that detects an input voltage from the solar cell; switching circuit that converts the input voltage to supply a charging current to the battery pack; charging current detection circuit that detects the charging current; and control circuit that controls the switching circuit to change the input voltage in order that a resultant charging current becomes suitable for charging the battery pack.

Abstract: A charging device includes a battery voltage detecting circuit for detecting the voltage of a battery pack; and a microcomputer having RAM for temporarily storing a battery voltage detected by the battery voltage detecting circuit, and a CPU for calculating a battery voltage gradient from the battery voltage detected by the battery voltage detecting circuit and a battery voltage sampled a prescribed time earlier. The charging device determines that the life of the battery has expired when the voltage of the battery pack prior to charging is less than or equal to a prescribed value J and the battery voltage gradient within a prescribed time period after the start of charging is greater than or equal to a first prescribed value K. The charging device also includes a display circuit for notifying the user when the life of the battery pack has deteriorated.

Abstract: There are provided a cordless power tool powered by a power supply unit that does not require a charging device and a charging power supply unit and an accommodation case thereof. In a cordless power tool, a front-end tool 24 provided in a housing 20a is driven by an electric motor 21 which uses a battery attached within the housing 20a and 20b as a motive power supply unit. The battery includes a fuel cell battery body 31 and a fuel tank 33 or a fuel cartridge 32 that stores fuel and supplies the fuel to the fuel cell battery body 31. The fuel tank 33 or the fuel cartridge 32 is detachably attached within the housing 20b in conjunction with or separate from the fuel cell battery body 31.

Abstract: An electrical power tool includes a housing, an electrical motor, an end-bit holding section, a transmitting mechanism, a cap, and a lighting section. The housing has one end. The electrical motor is accommodated in the housing and is configured to generate a rotational driving force. The end-bit holding section is provided at the one end and is rotatable about a rotational axis. The transmitting mechanism transmits the rotational driving force to the end-bit holding section. The cap is attached to the one end. The lighting section allows an entirety of the cap to be luminous.

Abstract: In a charging device, a driving power supply circuit for driving a control circuit is formed as a separate system from a first power supply circuit, regardless of whether the first power supply circuit is in a driving state or a non-driving state. A microcomputer alternately and intermittently controls the first power supply circuit in the driving state or the non-driving state when the battery pack is not mounted in the charging device in order to reduce the potential difference between the battery pack and the output voltage of the first power supply circuit, thereby avoiding an excessive discharge current from the battery pack when the battery pack is mounted in the charging device.

Abstract: For a lithium battery pack including battery cells the number of which is larger than the number of battery cells 111 that can be monitored by a voltage detect portion 115, there is disposed a temperature detect element 113 for detecting the temperatures of the battery cell 112 not monitored by the voltage detect portion 115, and, when the temperatures of the battery cell 112 detected by the temperature detect element rise beyond a given value, there is issued a signal to stop the charging of the battery pack.

Abstract: A battery charging apparatus includes a switching power source supplying a current to a battery pack, an input voltage detecting unit detecting an input voltage of the switching power source, a charging current control unit that detects a charging current of the battery and controlling the charging current in accordance with a charging current set value, and a microcomputer detecting whether the current supplied to the battery to be charged is less than a predetermined value on the basis of a detection signal of the input voltage detecting unit and controls the charging current set value in accordance with the input voltage. When it is discriminated that the input voltage is less than a predetermined value on the basis of the detection signal, the microcomputer sets the charging current set value to be a value less than the predetermined value.

Abstract: A battery charger including a charging power supply circuit connected to an input power supply and adapted to charge a battery to be charged, a charging control circuit adapted to control charging of the battery, and a constant voltage power supply adapted to drive the charging control circuit, wherein the charging control circuit stops an output of the constant voltage power supply when the battery is detached from the charger.

Abstract: A charging system has a battery pack and a charging device. The battery pack has a battery cell and a plurality of identifiers that identify a configuration of the battery cell. The charging device has a charging unit, a signal transmission unit, a reading unit, and a control unit. The charging unit charges the battery pack. The signal transmission unit transmits a first signal and a second signal to the battery pack separately to read the plurality of identifiers when the battery pack is attached to the charging unit. The reading unit reads the plurality of identifiers according to the first and second signals to determine the configuration of the battery cell. The control unit controls the charging unit according to the configuration of the battery cell.

Abstract: A charging device has a charging unit and a control unit. The charging unit charges a battery pack the battery pack being either a first type or a second type of battery pack. The first type of battery pack includes a single battery cell or a first plurality of battery cells connected in series. The second type of battery pack includes a single battery unit or a second plurality of battery units connected in series. Each battery unit includes at least two battery cells connected in parallel. The control unit controls the charging unit to control at least one of a charging current flowing through the battery pack and a charging voltage applied across the battery pack, depending on the battery pack to be charged.

Abstract: A setting current switching circuit 120 includes a comparator 127. A battery temperature signal corresponding to a battery temperature detected by a battery temperature detecting unit 8 is inputted to one input terminal (?) of the comparator 127 and a reference signal corresponding to a reference temperature is inputted to the other input terminal (+) of the comparator 127 to vary the setting charging current value of a charging current setting unit 80 and the setting full-charge current value of a full-charge current setting unit 90 correspondingly to the output of the comparator 127.

Abstract: A cordless power tool uses a lithium battery as a power source of a motor and is provided with an overcurrent protection circuit. The circuit allows an overcurrent to instantaneously flow at the start-up time of the motor and shuts off an overcurrent which may flow when the motor is brought into a locked state during the use of the power tool.