| dc.description.abstract | In the first part of the study, we first compared the ionic liquid 0.8 m LiFSI/PMP-FSI with the traditional carbonate electrolyte 1 M LiPF6/EC-DEC in a high voltage LiNi0.5Mn1.5O4/Li half-cell. 0.8 m LiFSI/PMP-FSI electrolytes can achieve better performance than 1 M LiPF6/EC-DEC in thermal stability and immersion experiments; however, aluminum corrosion occurs at 0.8 m LiFSI/PMP-FSI in high voltage environments. The problem is that it cannot be applied to LiNi0.5Mn1.5O4.
Continuing the results of the first part, the second part was modified for 0.8 m LiFSI/PMP-FSI. First, increase the lithium salt concentration to try to suppress the aluminum corrosion reaction. It is found that the higher the lithium salt concentration, the more the aluminum corrosion reaction can be inhibited, but the 3.2 m LiFSI/PMP-FSI is the maximum dissolved concentration and can not completely inhibit the aluminum corrosion. Therefore, it is necessary to find other methods to solve the aluminum corrosion problem.
In the second part, it was found that increasing the lithium salt concentration did improve the aluminum corrosion problem, but it could not be completely suppressed. Therefore, the addition of TFSI anion in the third part is expected to give better results. Compared with the pure FSI-based ionic liquid, the aluminum corrosion reaction after adding the TFSI anion is significantly reduced, and the aluminum corrosion can be solved under the condition of 0.8 m LiFSI/FT 13. However, it was found that its electrical performance in high-speed charge and discharge and graphite anodes is worse than that of pure FSI-based ionic liquids. Therefore, this study is expected to obtain the best electrical performance in improving the formulation.
In the fourth part, combined with the second and third parts of the study, while increasing the concentration of Li and TFSI, it was found that the aluminum corrosion problem can be suppressed under the formulation with a lower TFSI ratio, of which 2.4 m LiTFSI/PMP-FSI is inhibiting aluminum. Corrosion is slightly inferior to 0.8 m LiFSI/FT 13, but it performs better in high-speed charge and discharge and graphite anode. | en_US |