Diaphragm for secondary battery as well as preparation method and application thereof

The invention provides a diaphragm for a secondary battery as well as a preparation method and an application thereof. The diaphragm comprises a base material and a ceramic layer coated on at least one surface of the base material, the ceramic layer comprises a metal curing agent and a nano phosphate binder, and the mass of the nano phosphate binder is 12-38% of the mass of the ceramic layer. Compared with the prior art, the diaphragm provided by the invention has the advantages that the inorganic nano phosphate is added into the ceramic layer to serve as the binder, a traditionally used polymer binder is omitted, and meanwhile, the inorganic binder also has an excellent bonding effect, so that the problems that the polymer binder is easy to swell and easy to burn are solved. 本发明提供了一种二次电池用隔膜及其制备方法和应用，包括基材和涂覆于所述基材的至少一表面的陶瓷层，其中，所述陶瓷层包括金属固化剂和纳米磷酸盐粘结剂，所述纳米磷酸盐粘结剂的质量为所述陶瓷层质量的12～38％。相比于现有技术，本发明提供的隔膜，在陶瓷层中加入无机的纳米磷酸盐作为粘结剂，取消了传统使用的聚合物高分子粘结剂，同时本发明的无机粘结剂也具有优异的粘接效果，由此解决了高分子粘结剂易溶胀及易燃烧的问题。