| abstract |
The invention relates to a composite modified slurry for modifying battery separators, comprising: polyethylene oxide electrolyte film-forming material, mixed slurry of glacial acetic acid and LLZTO powder, and binder PVDF; polyethylene oxide electrolyte The film-forming material is PEO-LiTFSI or PEO-LiFSI, and wherein the mol ratio of PEO and Li is 6-10:1; in the mixed slurry of the glacial acetic acid and LLZTO powder, the solvent is DMF, and the LLZTO powder is Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 ; glacial acetic acid is 8-12% of the mass of LLZTO powder, and the amount of DMF is 8-12% of the mass of LLZTO powder; wherein, polyethylene oxide electrolyte film-forming material, LLZTO powder, binder PVDF The mass ratio of the three is 45‑55:36‑44:8‑12. After the base film to be modified, such as a PE diaphragm or a PP diaphragm, is impregnated with the composite modified slurry on both sides by a pulling method, then taken out and dried to obtain a modified diaphragm. After testing, the thermal stability, mechanical properties, electrochemical properties, interface stability and other properties of the modified separator have been significantly improved. |