Analysis of three commonly used components for cell phone battery circuit maintenance

Three commonly used components of mobile phone battery circuit maintenance The battery used in mobile phones is a lithium battery, which will explode at high temperatures with serious consequences. Therefore, most battery manufacturers use maintenance measures. In addition to structural design, IC overcurrent maintenance and MOS tube maintenance, secondary maintenance components will be selected to strengthen maintenance measures. There are three commonly used circuit maintenance components in mobile phone batteries: current fuse, temperature fuse and positive temperature coefficient thermistor. Different components reflect different maintenance requirements and different design concepts. The three commonly used components of cell phone battery circuit maintenance. Current fuse is mainly used for short-circuit maintenance: the maintenance principle is that once the battery is short-circuited, excessive overcurrent quickly destroys the normal operation of the thermal balance, and the instant the melt temperature reaches the melting point of the material, it will Disconnect the circuit to realize the safety maintenance function. The advantage of using current fuse maintenance is that the cutting circuit is fast and thorough, and the accuracy of the fuse characteristics is high. No matter when charging, using or standby, only any part of the short-circuit action is rapid. But it is only sensitive to current, not to outside temperature. Thermal fuse is mainly used for overheating maintenance: the principle of maintenance is to melt the melt made of low melting point alloy material after reaching the allowable temperature, and then cut off the circuit to realize the safety maintenance function. The advantage of using a thermal fuse for maintenance is that the internal and external temperatures of these two components are melted sensitively, especially when the phone is placed in a high-temperature environment. There may be other reasons for excessive temperature, but the overcurrent caused by excessive reaction temperature is relatively relatively high. Slow, low accuracy, low reliability current fuse. The positive temperature coefficient thermistor is mainly used for overcharge maintenance. The maintenance principle is to use the PTC resistance positive temperature coefficient material characteristics and the Curie temperature change characteristics, that is, the temperature rise caused by any reason (including overcurrent and environment) will cause the material resistance to increase, and once it rises to the Curie point, the resistance becomes It is large enough to cut off the charging current to realize the safety maintenance function. The advantage of thermistor maintenance is that it responds to current and temperature. When the battery is overcharged, the current will be limited. The disadvantage is that the response time is slow. The positive temperature coefficient thermistor is also called a self-recovery fuse, but the self-recovery function is not necessary in the maintenance of the mobile phone battery, especially the overcurrent caused by the circuit fault. If the fault is not eliminated and the PTC self-recovery, the actual application is meaningless. There are also some low-grade mobile phone batteries. In order to save costs, there is no need to repair components. Perhaps using zero-ohm resistors as repair components to fool the supporting manufacturers or customers is irresponsible and poses a considerable safety risk. Disclaimer: Some pictures and content of articles published on this site are from the Internet, please contact to delete if there is any infringement. Previous: Lithium battery Bluetooth headset charging parameters