TU-TESL

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Foreign media reported that Panasonic announced the development of a new management technology, which can measure the electrochemical impedance of multi unit stacked lithium batteries, accurately evaluate the residual value of lithium-ion batteries, so as to improve the recycling value of used lithium batteries. It is understood that Panasonic has developed this technology in cooperation with Professor Fukui Zhenghong of Ritsumeikan University. Panasonic has developed a new battery monitoring chip (BMIc), which includes test chip, measurement algorithm and software. However, Li Mingguan university has used the actual battery to evaluate its performance. The newly developed battery management technology uses the AC current excitation method to measure the electrochemical impedance of the stacked lithium battery modules installed in the application device. The purpose of this technology is to evaluate the residual value through the analysis of the collected measurement data, through the degradation diagnosis and fault estimation. Traditional BMIc can only measure 6 to 14 single electromagnetic films of lithium battery in series. Panasonic's new technology can accurately measure the battery voltage data of up to 200 series connected batteries, and monitor the battery to ensure its safety. The measurement of electrochemical impedance is realized by 15 fully parallel analog / digital converters, an AC current excitation circuit with pulse modulation from 0.1 Hz to 5 kHz, and a complex voltage / complex current conversion circuit built in BMIc. Panasonic's BMIc can measure the electrochemical impedance of the running battery without changing the parameters of the management software installed in the battery.. Because the electrochemical impedance of lithium-ion battery is very sensitive to temperature change. Because of the heating of the running battery module, the stable measurement of the electrochemical impedance cannot be realized. Therefore, limianguan University and Panasonic developed a temperature correction technology, which can measure the temperature of lithium battery in the process of electrochemical impedance measurement, correct the temperature change of impedance to the standard temperature, and then draw it on the cole Cole chart. In this way, even if the ambient temperature of the lithium battery changes according to the season and time, it can be accumulated and standardized into the cole Cole diagram of the standard temperature in the database.