The invention belongs to the technical filed of battery charging, and provides a multifunctional power supply system based on a dual-variable type intermittent pulse algorithm, and a charging method therefor. The multifunctional power supply system comprises a controller, a charging module, a sensor module, a display module, an alarm module, a lithium battery, a discharging voltage boost-buck protection module, and a voltage and current detection module, wherein the controller is connected with the charging module, the sensor module, the display module, the alarm module, and the voltage and current detection module separately; and the lithium battery is connected with the charging module, the sensor module, the discharging voltage boost-buck protection module, the voltage and current detection module and an external direct current power supply separately. The multifunctional power supply system is a charging system based on the dual-variable type intermittent pulse algorithm; the algorithm is creative, and the charging system has wireless and wired charging modes; the lithium battery is subjected to temperature and pressure compensation through temperature and pressure, so that the charging process for the battery is safer, quicker and more reliable; and in addition, the multifunctional power supply system has alarm and visual functions, so that the charging condition can be mastered in time in a more visualized manner.