Research On The Internal Temperature Measure-Ment Method Of Power Battery Based On ERT

The internal temperature of the power battery is an important indicator of battery safetyapplications. The temperature detection cell mainly concentrated in the sensor to obtain sur-face temperature battery, or to measure the internal temperatures of the whole battery athome and abroad, which can not detect the local temperature internal power battery. There-fore,"research on the internal temperature measurement method of power battery based onERT" as a topic, the electrical resistance tomography (ERT) internal temperature detec-tion method is applied to lithium ion power battery. The research project has important aca-demic value and practical significance for the rapid development of nondestructive testingtechnology, new energy vehicles and energy-saving environmental protection strategicemerging industry. The research work is funded by Projects in key areas of Guangdong andHong Kong (2012A090200005) in2012, Fundamental Research Funds for the Central Uni-versities (2012ZZ0056) in2012and Technology Plan Project of Guangdong in2012(2012B020314001).Firstly, the paper described the temperature detection of lithium ion battery at homeand abroad, and the application of electrical resistance tomography in different fields, then putforward that use the ERT method to detect the internal temperature of the power bat-tery. Through the elaboration of electrical resistance tomography principle, the framework ofthe internal temperature of the battery power detection system was established. As the lionpower battery has the characteristics of small volume, complex structure, the ERT electrodedevice mode of Wenner-Schlumberger was put forward, which can probe much deeper andcan achieve higher detection sensitivity. In the design the bipolar pulse current was selectedas the excitation current, and the voltage signal was changed into a current signal throughthe voltage controlled current source; and for the general election of excitation electrode andmeasuring electrode was realize through logical switch; the voltage that measured was verysmall, it need to zoom in by two signal conditioning, and then collected by the samplingmodule; then reconstructed the images of the quasi Newton method of least squares, andthe artifact noise in an image was removed by the fuzzy threshold method. Because what theERT method detect is resistivity, and it is not the temperature, and there is no research on therelationship of the internal temperature of power battery and apparent resistivity, the model-ing and Simulation of lithium ion power battery is detected by the finite element simulationsoftware ANSYS, and the distribution of battery internal temperature and electric field weregot, and then fitted the relationship of them. Finally, the experiment platform is constructed to test. Numbers of the factors were se-lected through the orthogonal experiments. The Schlumberger arranged, circular electrodeand excitation current of2.6mA were selected at last. After that, the internal temperature oflithium ion power battery static、dynamic detection test series. The results showed that theinternal temperature measurement method that was about power battery based on ERT canrealize the internal temperature detection and track mutation region real-time.