Electric circuit breaker device

An electric circuit breaker device comprising:

• an igniter provided to a housing;
• a projectile disposed in an accommodating space, the accommodating space being formed in the housing and extending in one direction, the projectile being to be projected along the accommodating space by energy received from the igniter;
• a conductor piece that is provided to the housing, forms a portion of an electric circuit, includes in a portion thereof a cutoff portion to be cut off by the projectile that moves by the energy received from the igniter, and is disposed with the cutoff portion crossing the accommodating space;
• an arc-extinguishing region positioned within the accommodating space, on a side opposite to the projectile prior to actuation of the igniter with the cutoff portion interposed between the arc-extinguishing region and the projectile, and configured to receive the cutoff portion cut off by the projectile;
• a first coolant material disposed in the arc-extinguishing region;
• and
• a second coolant material disposed between the projectile and the cutoff portion in the accommodating space prior to actuation of the igniter,
• wherein the second coolant material is solid, and
• the second coolant material is formed from a metal fiber.