Monitoring method for remaining power of wireless sensor network node and device thereof

The invention provides a monitoring method for remaining power of a wireless sensor network node. The method comprises steps of building a lithium battery RC?equivalent model to obtain a state equation after discretization, estimating the current state variable value, updating an estimation variance and calculating Kalman gain according to the variance, updating state?variable battery remaining power?SOC and battery open circuit voltage, and comparing voltage in a register with the battery open circuit voltage obtained in the former step. A device using the method comprises a data acquisition module for sampling voltage, current and temperature of the battery, a Flash memory module for storing data, a voltage conversion module for providing power for the device and the sensor, a battery charging module, and an embedded microprocessor for receiving and processing relative battery data of the data acquisition module, and the data acquisition module is connected with the embedded microprocessor via an I2C bus.