A method including forming a first layer comprising a chemical conversion coating on a metal surface; and forming a second layer on the first layer through a sol gel process. An apparatus including a metal component having at least one surface; a first layer comprising a chemical conversion coating on the at least one surface; and a second layer derived from a sol gel composition on the first layer.

Various coatings and methods of coating fasteners are disclosed. In one embodiment, a method of coating includes applying a chromate coating to a fastener. In other embodiments, the method may include deoxidizing an aluminum fastener, etching the fastener, deoxidizing the fastener a second time, applying a chromate coating to the fastener, and dying the fastener.

A method including forming a first layer comprising a chemical conversion coating on a metal surface; and forming a second layer on the first layer through a sol gel process. An apparatus including a metal component having at least one surface; a first layer comprising a chemical conversion coating on the at least one surface; and a second layer derived from a sol gel composition on the first layer.

The present invention is directed to a battery separator. The battery separator comprises a microporous film having a first portion and a second portion. The first portion is bonded to the second portion. The bond has a strength greater than 5 g/in. The film has a thickness less than 1.7 mils, a Gurley of less than 50 sec/10 cc, and a puncture strength of greater than 400 g/mil.