POROUS SEPARATOR FOR A SECONDARY BATTERY INCLUDING CELLULOSE NANOFIBERS AND METHOD FOR MANUFACTURING SAME

The present invention relates to a separator for secondary battery including cellulose nanofibers, and to a method for fabricating the same. The separator has a porous structure of micropores formed between the cellulose nanofibers. The porous structure has a porosity of 10 to 80 % (v/v) and a pore size of 0.01 to 10 µm. The separator has a thickness of 5 to 30 µm. The separator has good properties in regards to thermal stability, dimensional stability, wettability, and electrochemical stability, and the fabrication process can be simplified to reduce the production cost.