METHOD OF FORMING PROTECTIVE COATING ON CELL SAFETY VALVE ELEMENT, CELL SAFETY VALVE ELEMENT COATED WITH PROTECTIVE FILM, CELL SEALING PLATE USING THE ELEMENT, AND ENCLOSED CELL USING THE PLATE

摘要

The present invention provide a method of forming a protection film of a safety valve element for battery which prevents from corroding a metal portion by covering protection film on the safety valve element for battery, a closing plate for a battery using same and a closed battery using same. A safety valve element of the present invention is composed of a safety valve element 10 comprising a metal substrate 1 having a perforated pore 4 and a metal foil 2 laminated on a metal substrate 1 so as to cover perforated pore 4 and a protection film 3 which is formed by coating an organic coating at least on one side of a safety valve element 10. Further, a closing plate puts a safety valve element 10 to provide a protection film 3 which is coated with organic film on a closing plate 6 of battery container to provide perforation 4 which is an opening of a safety valve so as to face perforations of a metal substrate 4 and perforation of a closing plate 7 and then to glue around perforation of a closing plate 7, and a closing plate of a battery is made. Furthermore, there is closed an opening of a battery container that fixes electrode which consist of positive electrode, negative electrode and separator, and a closed battery is made.