UROP Proceedings 2021-22

School of Engineering Department of Chemical and Biological Engineering 82 Anode Materials for Lithium Ion Batteries Supervisor: SHAO Minhua / CBE Student: KWAN Yee Tung / SUSEE Course: UROP1100, Spring Due to the rising demand for higher energy density batteries, interest arises in the implementation of highvoltage cathodes in the field of Li-ion batteries, such as LiNi0.5Mn1.5O4 and Ni-rich layered oxides. However, the electrochemical stability windows of prevailing electrolytes are insufficient to withstand such a high voltage operation. Highly concentrated electrolytes have been a notable strategy to deal with the stability issue due to the special structure and improvement in electrolyte stability. In this project, Lithium batteries with the LiNi0.8Co0.1Mn0.1O2 cathode are assembled with 1,3-dioxolane as a solvent and LiTFSI as a salt with different salt to solvent weight ratios. Cycling tests of 100 charging and discharging cycles are performed on the batteries to evaluate their capacity retentions. Anode Materials for Lithium Ion Batteries Supervisor: SHAO Minhua / CBE Student: SO Kwok To Timothy / SENG Course: UROP1000, Summer To improve the next generation of Li-ion battery, it is very important to maintain the stability and efficiency of the battery. NCM811 battery has been a common choice due to its high energy density and being cost effective, however it suffers from poor cycling stability. There are many projects on how different electrolytes could improve this. Particularly lithium hexafluorophosphate (LiPF6) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). However, these electrolytes, particularly LiTFSI causes corrosion on the aluminium current collector which decreases its efficiency and stability. In this project, the effect of carbon coated aluminium will be explored to see whether it does improve the corrosion issue present in the current collector. The cells with NCM811 cathode, Li metal anode would be assembled and subjected to charging and discharging cycle 75 times to test the effect of carbon coating.