초록 ▼

A secondary battery which may be handled in a same way as conventional single cell, if the gas pressure within battery went unusually high the gas is immediately discharged outside, and bursting of the battery is prevented. Sealing portion of the secondary battery is composed by a flexible circuit b

A secondary battery which may be handled in a same way as conventional single cell, if the gas pressure within battery went unusually high the gas is immediately discharged outside, and bursting of the battery is prevented. Sealing portion of the secondary battery is composed by a flexible circuit board having an aperture and a safety circuit mounted thereon, a plus terminal for input/output of control provided with a gas discharge aperture and minus terminal for safety circuit provided with a gas discharge aperture which keep a surface contact with the flexible circuit board at the upper surface and are connected respectively to the safety circuit by wirings, a PTC element keeping a surface contact with the flexible circuit board at the reverse surface, a vent having a slit and is attached to the reverse surface of PTC element, the above members being united into a one-piece unit by an inner gasket, and a subfilter having an aperture and is welded to said vent at the center, which is clamped, together with the inner gasket, by the circumferential edge of an aperture-bearing filter.

대표청구항 ▼

[ What is claimed is:] [1.]1. A secondary battery comprising:an electronic safety circuit containing a voltage detector and an FET as a current cutting element, the FET turning the current on and off in accordance with a voltage detector value, incorporated in a sealing cap for sealing the battery,

[ What is claimed is:] [1.]1. A secondary battery comprising:an electronic safety circuit containing a voltage detector and an FET as a current cutting element, the FET turning the current on and off in accordance with a voltage detector value, incorporated in a sealing cap for sealing the battery, wherein a substrate board having the electronic safety circuit disposed thereon is provided with an opening or a breakaway structure.