NOVEL MODIFIED NON-WOVEN FABRIC LITHIUM-ION BATTERY DIAPHRAGM AND PREPARATION METHOD THEREFOR

摘要

A modified non-woven fabric lithium-ion battery diaphragm. The diaphragm comprises a modified non-woven fabric substrate (1) and a filling agent (2) compounded thereon. The modified non-woven fabric substrate (1) comprises a low-smelting-point material and a high-smelting-point material, wherein the low-smelting-point material is subjected to melt crystallization treatment, and the weight of the high-smelting-point material accounts for 85-99.9% of the total weight of the substrate, and the low-smelting-point material accounts for the rest of the total weight; the filling agent (2) compounded on the modified non-woven fabric substrate (1) comprises an organic polymer, a first filling material and/or a second filling material. A preparation method of the battery diaphragm sequentially comprises the following steps: manufacturing a non-woven fabric fiber layer, manufacturing a modified non-woven fabric substrate (1); preparing filling agent slurry (2); filling; removing a solvent; and carrying out post-treatment. The method is simple in operation and low in cost, and the prepared product is low in water content, good in chemical stability and high in mechanical strength, and the yield rate of the battery is increased, the service life of the battery is prolonged and the safety of the battery is improved.