PROTECTION ELEMENT, PROTECTION CIRCUIT FOR SECONDARY BATTERY, BATTERY PACK, AND BATTERY STATE MANAGEMENT SYSTEM

摘要

PROBLEM TO BE SOLVED: To give a function of an antenna to a protection element, and inform a user of an excessive current flowing in the protection element with certainty by wireless communication.SOLUTION: A protection element comprises: a first electrode, a second electrode, a third electrode and a fourth electrode formed on an insulator; a first soluble conductor connected with the first electrode and the second electrode; a conductor whose one end side at a power feeding side is connected with the third electrode; a second soluble conductor disposed between the other end side of the conductor and the fourth electrode that is grounded in terms of high frequency; and a heater element for heating the first and second soluble conductors. The second soluble conductor melts prior to the first soluble conductor, and a function as an antenna is given to the conductor.SELECTED DRAWING: Figure 5