Other

Sony Corporation

Ayaki Watanabe

Takayuki Yamahira

Koji Kihara

Toshizou Kameishi

An extremely safe non-aqueous electrolyte secondary cell free of explosions and which can promptly release the internal pressure in case of rise in the internal pressure. The non-aqueous electrolyte secondary cell has in its opening a cleavage valve obtained on bonding a metal foil to the opening. In case of rise in the internal pressure, the cleavage valve is cleft to release the pressure. In this cell, a value K corresponding to the internal volume in the cell in cm divided by the area of the opening in cm is set so that 40&lE;K&lE;350. By selecting the value K to a suitable value, the cleavage valve is in operation when the internal pressure reaches a predetermined value to release the pressure. The metal foil is produced by, for example, a electro-forming method or a cladding method. Preferably, a fluorine-based water-proofing agent is coated on the foil surface.

Growing community of inventors

Fukushima, Japan

Ayaki Watanabe