A high current fuse with a short time constant is provided for use in an electric vehicle. The fuse is designed to exhibit thermal characteristics that are similar if not substantially identical to those of the wire bond interconnects used in the vehicle's battery pack. As a result, the system does not go into an overheat protection condition when the system is subjected to repetitive high current cycles, such as those common during aggressive and/or spirited driving.

A high-voltage direct-current thermal fuse, includes a high-voltage low-current thermal fuse connected to a high-voltage direct-current circuit. The high-voltage low-current thermal fuse includes a casing, fusible alloy wires, and two leads extending out of the casing. The fusible alloy wires are connected between the two leads. One of the leads is sequentially sleeved with an arc extinguishing sleeve and a spring. One end of the arc extinguishing sleeve is in contact with the fusible alloy wires; and the other end of the arc extinguishing sleeve is in contact with the spring. One end of the spring is connected to the internal end face of the casing; and the spring is in a compressed state. The high-voltage direct-current thermal fuse further includes a conventional thermal fuse connected in parallel to the high-voltage low-current thermal fuse; or further includes a current fuse connected in series with the high-voltage low-current thermal fuse.

A high current fuse with a short time constant is provided for use in an electric vehicle. The fuse is designed to exhibit thermal characteristics that are similar if not substantially identical to those of the wire bond interconnects used in the vehicle's battery pack. As a result, the system does not go into an overheat protection condition when the system is subjected to repetitive high current cycles, such as those common during aggressive and/or spirited driving. The fuse includes an arc suppressor.

A high current fuse with a short time constant is provided for use in an electric vehicle. The fuse is designed to exhibit thermal characteristics that are similar if not substantially identical to those of the wire bond interconnects used in the vehicle's battery pack. As a result, the system does not go into an overheat protection condition when the system is subjected to repetitive high current cycles, such as those common during aggressive and/or spirited driving.

Provided is an excitation protection device acting step by step with a single excitation source, including a shell body, an excitation source, impact devices and a conductor, wherein at least two impact devices respectively located in different cavities are provided in the shell body, one side of the impact device is provided with one excitation source, and the impact device and the excitation source are respectively in sealed contact with the cavities where the impact device and the excitation source are located; and the excitation source drives the impact devices to displace simultaneously or successively, and at least one of the impact devices breaks the conductor during the displacement process.

A high-voltage direct-current thermal fuse comprising a high-voltage low-current thermal fuse connected to a high-voltage direct-current circuit. The high-voltage low-current thermal fuse comprises a casing, fusible alloy wires, wherein the fusible alloy wires are connected between the two leads. One of the leads is sequentially sleeved with an arc extinguishing sleeve and a spring. One end of the arc extinguishing sleeve is in contact with the fusible alloy wires; and the other end of the arc extinguishing sleeve is in contact with the spring. One end of the spring is connected to the inner end face of the casing; and the spring is in a compressed state. The high-voltage direct-current thermal fuse further comprises a conventional thermal fuse; or further comprises a current. The high-voltage direct-current thermal fuse solves the problem of timely arc cutting-off and can be directly applied to a high-voltage direct-current circuit.