Chromium-based metal-organic framework coated separator for improving electrochemical performance and safety of lithium-ion battery

To improve the electrochemical performance and safety of the traditional polymer separator, two kinds of chromium-based MOFs (Cr-MOFs) (namely MIL-88B(Cr) and MIL-101(Cr)) were studied as separator coatings. Compared with inorganic coating (Al2O3), Cr-MOFs coated separators exhibited improved thermal stability, better flame retardance, superior electrolyte wettability, high electrolyte uptake, good ionic conductivity and enhanced electrochemical performance. Moreover, although MIL-88B(Cr) and MIL-101(Cr) have the same metal center (Cr3+) and organic ligand (1,4-benzene dicarboxylate), their improvements on the performance of coated separators are obvious different. The detailed analyses reveal that the specific surface area, pore size and structure stability of Cr-MOFs are the main factors that affect their performances. The result of this work provides an essential basis for developing high performance separators with MOFs.

Automated summary

To improve the performance and safety of polymer separators, chromium-based MOFs (Cr-MOFs) namely MIL-88B(Cr) and MIL-101(Cr) were studied as coatings. Compared with inorganic coating (Al2O3), Cr-MOFs coated separators showed improved thermal stability, flame retardance, electrolyte wettability, uptake and conductivity, and enhanced electrochemical performance. The specific surface area, pore size, and structure stability of Cr-MOFs are identified as the main factors affecting their performance.