Composite diaphragm for lithium metal battery and preparation method of composite diaphragm

The invention discloses a composite diaphragm for a lithium metal battery, which is characterized in that a porous fiber membrane is used as a matrix membrane, and vinyl-terminated polysiloxane and double-bond-containing polyhedral oligomeric silsesquioxane are cross-linked and polymerized on the matrix membrane to form an organic-inorganic hybrid composite fiber membrane. The invention also discloses a preparation method of the composite diaphragm for the lithium metal battery. The composite diaphragm for the lithium metal battery has excellent electrolyte wettability and high porosity, and can promote uniform deposition of lithium metal in the charging and discharging process, effectively inhibit growth of lithium dendrites and improve the cycling stability of the lithium metal battery. 本发明公开了一种用于锂金属电池的复合隔膜，以多孔纤维膜为基质膜，乙烯基封端聚硅氧烷和含双键的笼型倍半硅氧烷于基质膜上交联聚合形成有机无机杂化复合纤维膜。本发明还公开了上述用于锂金属电池的复合隔膜的制备方法。本发明的用于锂金属电池的复合隔膜，具备优异的电解液浸润性、高的孔隙率，而且在充放电过程中还能促进锂金属的均匀沉积，有效抑制锂枝晶生长，提高锂金属电池的循环稳定性能。