MATE7016: Materials for Energy Conversion and Storage
Introduction. (3 marks)
In the introduction or background, student should clearly write the purpose of the experiment, the real-life applications of Li-ion batteries, how Li-ion batteries works, equations (if needed), challenges faced by commercial Li-ion batteries, how advanced Li- ion battery anodes may solve these problems (350 words).
Methods. (4 marks)
Student should briefly write the steps involved in the scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) characterisations, manufacturing of the Li-ion coin cells, and the electrochemical measurements (with parameters) of the coin cells. Include the purpose of using these methods whenever appropriate. (Passive form) (300 words).
Results. (4 marks)
The loading weight* of the two electrodes shall be calculated. Students need to include the following figures obtained from the experiment for the two electrodes: 1a) SEM image of the graphite electrode, 1b) SEM image of the Cu6 Sn5 electrode, 1c) EDS mapping of graphite electrode, 1d) EDS mapping of Cu6 Sn5 electrode along with Table 1) EDS quantitative analysis results. Students shall also plot the results generated in the electrochemical characterisation: 2a) voltage (V) vs. capacity (mAh); 2b) voltage (V) vs. gravimetric capacity (mAh g-1). The plots can be generated using excel or origin software.
Example:
Analysis and Discussion. (4 marks)
Students should discuss the morphologies and particle sizes of the two electrodes as observed in Figure 1a and b. The chemical compositions of each electrode shall be determined by the EDS results in Figure 1c and d and Table 1. Students need to carefully identify the discharge voltage plateaus of each electrode from figure 2a, and evaluate the data with existing literature. From Figure 2b, students should report the specific gravimetric of the two electrodes, and compare these values with existing literature.
Conclusion. (2 marks)
Brief description of the purpose of the experiment, findings, and analysis. Need to write any shortcomings of the experiments and potential application of this experiment for research and industry.
References. (1 mark)
Relevant references, cited in the correct format in the text and reference list.
Written communication. (2 marks)
Clear, concise and logical writing style.
*Loading weight is the weight of the active material deposited onto the Cu current collector. In the case of Cu6 Sn5, the loading weight is the difference between the mass of the electrode and the mass of the bare Cu foil; while in the case of the Gr electrode, only 90% of this mass is Gr and so the loading weight of Gr shall be calculated accordingly.