A battery overcharge preventing device according to an embodiment of the present invention includes: a voltage distribution unit connected to both ends of at least one battery cell in a battery module including multiple battery cells, the voltage distribution unit being configured to distribute a voltage of the at least one battery cell according to a preset ratio; a voltage sensing unit operating so as to allow a control current to flow when the voltage distributed by the voltage distribution unit is greater than a preset reference voltage; and a second relay configured to block, by operation of the voltage sensing unit, operation of a first relay that establishes an electrical connection between the battery module and a charging module.

A protection circuit 100 of a power storage device 20 equipped with external terminals 58A, 58B, the protection circuit 100 being equipped with a return circuit 110 connected in parallel to a load 12 connected between the external terminals, and also equipped with a switching circuit 120, wherein: the return circuit 110 is equipped with a return element 111 which causes an induced current produced when the current to the load 12 is blocked to return to the load 12, and a current-blocking part 115 which is connected in series to the return element 111; and the switching circuit 120 switches the current-blocking part 115 from conducting to blocking after a delay of a prescribed interval from when a reverse voltage is applied to the external terminals 58A, 58B.

Provided is a protection circuit capable of reliably preventing an overcurrent or a sneak current after cutoff to improve safety, implementing cost reduction with a device configuration simpler than conventional device configurations, and further reducing a failure rate of a device. In a protection circuit, after one of two fuse elements provided in each of a plurality of protection elements is blown due to an overcurrent flowing along a current-carrying path, a heater provided in at least one of the plurality of protection elements generates heat due to a sneak current flowing via the plurality of protection elements on the current-carrying path which is remained and blows the other of the two fuse elements provided in the at least one of the plurality of protection elements.

Provided is a protection circuit capable of reliably preventing an overcurrent or a sneak current after cutoff to improve safety, implementing cost reduction with a device configuration simpler than conventional device configurations, and further reducing a failure rate of a device. In a protection circuit, after one of two fuse elements provided in each of a plurality of protection elements is blown due to an overcurrent flowing along a current-carrying path, a heater provided in at least one of the plurality of protection elements generates heat due to a sneak current flowing via the plurality of protection elements on the current-carrying path which is remained and blows the other of the two fuse elements provided in the at least one of the plurality of protection elements.

This disclosure relates to an electrified vehicle configured to disconnect a battery from a load, and a corresponding method. An example electrified vehicle includes an array of battery cells and an electrical conductor connecting the array to a load. A disconnect is arranged along the electrical conductor. Further, the electrified vehicle includes an electronic circuit with a switch and an igniter. When a voltage drop across the electrical conductor exceeds a threshold, the switch is configured to permit current to flow from at least one of the battery cells through the igniter to trigger the disconnect thereby disconnecting the array of battery cells from the load.

This disclosure relates to an electrified vehicle configured to disconnect a battery from a load, and a corresponding method. An example electrified vehicle includes an array of battery cells and an electrical conductor connecting the array to a load. A disconnect is arranged along the electrical conductor. Further, the electrified vehicle includes an electronic circuit with a switch and an igniter. When a voltage drop across the electrical conductor exceeds a threshold, the switch is configured to permit current to flow from at least one of the battery cells through the igniter to trigger the disconnect thereby disconnecting the array of battery cells from the load.

This power supply circuit for work machine is provided with a first switch for switching connection and disconnection of a first electrical path provided between a battery and a load which is driven with the power of the battery, and a second switch for switching connection and disconnection of a second electrical path bypassing the first switch. The second switch, when the first switch is switched from a state in which the first electrical path is connected to a state in which the first electrical path is disconnected, places the second electrical path in a connected state for a certain period and then, after the period elapses, switches the state in which the second electrical path is connected to a state in which the second electrical path is disconnected.

This power supply circuit for work machine is provided with a first switch for switching connection and disconnection of a first electrical path provided between a battery and a load which is driven with the power of the battery, and a second switch for switching connection and disconnection of a second electrical path bypassing the first switch. The second switch, when the first switch is switched from a state in which the first electrical path is connected to a state in which the first electrical path is disconnected, places the second electrical path in a connected state for a certain period and then, after the period elapses, switches the state in which the second electrical path is connected to a state in which the second electrical path is disconnected.

A battery protection apparatus power protection apparatus is configured to protect an electrochemical cell connected to a load, and includes a protection IC, a switching transistor group, and a sampling resistor. The protection IC includes two power input terminals respectively connected to positive and negative electrodes of the electrochemical cell, and an operational amplifier, where the operational amplifier includes a positive input pin, a negative input pin, and an output pin. The switching transistor group is connected between the negative electrode of the electrochemical cell and the load, and is configured to control turn-on and turn-off of a charge and discharge circuit of the electrochemical cell. The sampling detection resistor Rs is serially connected between the sampling circuit detection terminal and the output pin, where the main circuit detection terminal is connected to the positive input pin, and the sampling circuit detection terminal is connected to the negative input pin.

A battery protection apparatus power protection apparatus is configured to protect an electrochemical cell connected to a load, and includes a protection IC, a switching transistor group, and a sampling resistor. The protection IC includes two power input terminals respectively connected to positive and negative electrodes of the electrochemical cell, and an operational amplifier, where the operational amplifier includes a positive input pin, a negative input pin, and an output pin. The switching transistor group is connected between the negative electrode of the electrochemical cell and the load, and is configured to control turn-on and turn-off of a charge and discharge circuit of the electrochemical cell. The sampling detection resistor Rs is serially connected between the sampling circuit detection terminal and the output pin, where the main circuit detection terminal is connected to the positive input pin, and the sampling circuit detection terminal is connected to the negative input pin.