Design And Implementation Of The Lithium-ion Battery Safety Testing Of Experimental Platform

The safety of the lithium-ion battery is a key issue in the application of thelithium-ion battery. The lithium-ion battery has lots of advantages such as highercapacity, longer life time and green pollution-free, which make it the most importantenergy storage device and been widely studied. Nevertheless, it also has somedisadvantages such as leakage, swell, combustion, which makes it dangerous. It canclearly be seen that the safety is of the bottleneck issues that restrict the developing ofthe lithium-ion battery. Therefore, research in new measurement technology and devicesis the most important things in solving the safety issue of the lithium-ion battery.Hierarchical control structure of the upper and lower levels is used in thedissertation, which makes user operation and on-site control separate. In this research, atfirst by inspecting extensive literature, the author simply elaborated the basic principleof the lithium-ion battery. Then focused on lithium-ion battery safety features andelaborated the impedance characteristics, charge or discharge behavior and temperatureproperty for the safety of the lithium ion battery, and finally developed this articledetection system design.1. The upper and lower control system is firstly designed in this dissertation. Onthis basis, it starts the system software design and improves the function and design thehardware circuits. For the impedance characteristics, charge and dischargecharacteristics, thermal characteristics of the three security impact factors, weredesigned for a different function test module.2. Electrochemical impedance spectroscopy methods is used in impedance testmodule which first add a disturbance signal to the battery and test its correspondingresponse signal, after the pulse mean filter processing, a lithium ion battery of the EISspectra is calculated, and then through the spectrum fitting to speculate that theequivalent circuit of the battery system or the corresponding mathematical model, andthus can be analyzed in which the kinetic parameters and other information.3. A proper topology is designed in the charge-discharge test model to producelarger current. In normal node, constant current followed by constant voltage method is used to help fully charge the battery to achieve the best performance, while providingovercharge experimental features.4. Unbalanced electronic bridge is used in temperature test model. The PT100resistance is as one of the bridge arms and has a high temperature alarm function.Finally, verifying the actual system, all test data are able to visually display on theuser control interface screen. The results show that, due to the different charge anddischarge operation of the battery, the impedance spectra by the battery which theimpact of different electrochemical reaction occurs necessarily a change, the same time,impedance changes, leading to a variation in characteristics of the battery thermal. Theexperiments show that the battery impedance spectroscopy has certain guidingsignificance for the study of battery internal features and strict control over the use oflithium-ion battery charge overheating occurred.