Explosion resistant vent cap

DETAILED DESCRIPTION The present invention provides a vent cap for use in a recombinant battery which includes a hollow barrel configured for gas-tight insertion into a vent hole in a battery cover, the barrel having an open end and a closed end, a retaining flange formed at the closed end of the barrel, a one-way relief valve formed on the barrel near the closed end thereof, and a layer of a polyalkylene explosion attenuating material surrounding the outside of the barrel below the flange and in contact with the flange, and surrounding the relief valve.
The polyalkylene material provides effective attenuation of explosions that occur in the vicinity of the relief valve.
The invention further provides a vent cap assembly wherein the foregoing vent cap is mounted on a plastic vent cover of an otherwise conventional battery container.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following drawing, detailed description and claims.