(39c) Electrochemical Characteristic Evaluation of Lithium-Ion Battery Slurry By a Multi-Sensing Electrochemical Impedance Spectroscopy System

Lithium-ion battery (LIB) is widely used in electronic equipment on account of their high energy density, no memory effect, relatively good safety and cycling-life performance. The performance of LIB is affected mainly by the electrochemical characteristic of the LIB slurry
. However, in the previous research, most of the researchers focused on the performance of the anode electrodes instead of the slurry. Therefore, the main influenced factors for the performance of LIB need to be more considered during the slurry stage.
In the present study, we aimed to evaluate the electrochemical characteristic of Lithium-ion battery slurry by using of a Multi-sensing Electrochemical impedance spectroscopy system. The Multi-sensing EIS system is composed of a main board with a field programmable gate array (FPGA), a switching module and an eight electrode EIS sensor. Compare to the conventional used impedance analyzer for EIS measurement, the developed system achieved agile and compact feature for the real-time measurement of impedance spectroscopy. Instead of conventional two electrodes method, an eight electrode EIS sensor was used. The eight electrodes are attached at equal intervals on the outside of a circular glass beaker. Measurement is performed between various combinations of electrodes including adjacent and opposing electrodes or between opposing electrodes to obtain more comprehensive measurement information of the measurement domain.
By using the Multi-sensing EIS system, a Nyquist diagram between the respective electrodes is obtained. The electrode combination dependence on the measured Nyquist diagram is discussed firstly. The electrodes independent EIS data was analyzed deeply to evaluate the electrochemical characteristic of Lithium-ion battery slurry. Eventually, validation of the proposed multi-sensing EIS system was also conducted to clarify its capability to realize the online measurement of electrochemical characterizations for LIB slurry.