1. Field
Aspects of the present invention relate to a secondary battery.
2. Description of the Related Art
Generally, secondary batteries can be discharged and recharged, unlike primary batteries, which are not rechargeable. Secondary batteries may be of a low capacity type, which includes battery cells in the form of a pack typically used for small portable electronic devices such as cellular phones and camcorders, or a high capacity type, which includes battery cells used as a motor-driving power source and having several battery cells connected to one another and widely used as a power source for hybrid vehicles, etc.
Secondary batteries may be manufactured in various shapes, such as cylindrical shape or prismatic shapes. A typical secondary battery may include an electrode assembly having a positive plate and a negative plate with a separator acting as an insulator between the positive and negative plates accommodated in a battery case with an electrolyte, and a cap plate having electrode terminals coupled to the case.
When an internal pressure of a secondary battery rises due to excess heat generated by over-charging or decomposition of an electrolytic solution within the battery, a fire or explosion may occur within the secondary battery. Accordingly, it is necessary to manufacture a secondary battery having improved safety.