Indiana University-Purdue University Indianapolis

IUPUI School of Engineering and Technology

Modeling and characterization of lithium ion batteries

project 2

Reconstructed LiCoO2 cathode from a
commercial LIB using MIMICS.

Electric vehicles powered by advanced batteries are driving the change to a clean and sustainable future for the United States and the world. Extensive research has been conducted to develop advanced lithium ion battery (LIB) technologies to meet the demands of the ground transportation industry for LIBs with higher energy and power densities, lower cost, and safer operation. In addition to the development of advanced materials for the anode, cathode, and electrolyte, the structure of the electrodes at the micro- and nano-scales also plays a critical role in determining the performance of a LIB because the electrode’s composite matrix must be designed to provide both electron and lithium ion transportation, which eventually affects the LIB’s voltage, specific capacity, and discharge/charge rate. Currently, a fundamental understanding of the impact of an electrode’s microstructure on LIB performance is still lacking due to the inhomogeneity, complexity, and three-dimensional (3D) nature of the electrode’s microstructure.

 

project 2

Reaction heat generation rate at the interface
between the electrolyte and the cathode particles
during a 5 C discharge process

In our group, we are developing novel approaches to gain greater understanding of the microstructure of the electrode and its impact on the LIB’s physical and electrochemical performances. Our research takes an interdisciplinary approach using experimental and theoretical analysis tools from electrochemistry, nanotechnology, transmission x-ray microscopy, material science, and numerical modeling. For instance, as shown in the figures on the left, we have used micro/nano computed tomography (CT) technology to obtain the realistic 3-dimentional microstructure of LIB electrodes. Based on the experimentally determined microstructure of a LIB electrode, a three dimensional simulation framework has been developed to simulate the charge/discharge processes, thermal transport, and stress development in LIBs.