The invention relates to an intelligence detecting and controlling device and a detecting and controlling method of an accumulator belonging to the detecting, controlling, and adjusting device technology field. The device comprises a casing body, a liquid level sensor, and a voltage connecting piece. The lower portion of the casing body is provided with a location base which is connected with a measured accumulator. The inner portion of the casing body comprises a control circuit board and a stepper motor for lifting a float, and sensor components comprise a density sensor and a temperature sensor. The control circuit board comprises a signal conditioner, a micro processor, a CAN communication isolating circuit, a drive circuit, and a boosted circuit. The density sensor is connected with the micro processor through the signal conditioner, and the stepper motor is connected with the micro processor through the drive circuit. The invention has the advantages of simple structure, which can lead the acid solution density, temperature, and the detecting and controlling of liquid level of a lead-acid accumulator to have continuous on-line proceed, and the invention has the function of self-diagnosis and on-line calibration, and the operation is stable and reliable. The detecting and controlling method comprises, connecting with equipment, assuring the parameter range, calibrating parameter values, and assuring or returning. The process has the advantages that continuous on-line self-diagnosis and on-line calibration method is simple and direct, fast, and accurate, and work efficiency is high.