Patent ID: 7807282
Filing Date: 2010-10-05
Classification: H01M,Y02E

Abstract:
1. A nickel-metal hydride storage battery comprising: a battery main part; a case which houses the battery main part; and a safety valve device having an excessive pressure preventing function for preventing excessive rise of internal pressure in the case by discharging gas from the case when the internal pressure in the case exceeds a predetermined value; wherein: the case includes a release hole formed through the case to provide communication between inside and outside of the case, the safety valve device includes a valve member sealingly covering the release hole and including a wall forming a valve internal space communicated with the release hole, the wall of the valve member, forming the valve internal space, includes a hydrogen permeable part, which allows hydrogen gas to leak out from the valve internal space by hydrogen permeation even when the internal pressure in the case is the predetermined value or less, the valve member includes a sealing part held in close contact with a portion of the case around the release hole, and the wall forming the valve internal space is a protruding wall formed to protrude from the sealing part out of the case, serving as the hydrogen permeable part.