Patent ID: 7326489
Filing Date: 2008-02-05
Classification: B01J,H01M,Y02E

Abstract:
1. A valve regulated lead acid (VRLA) battery cell comprising: a sealed housing; a positive electrode positioned in the housing; a negative electrode positioned in the housing in spaced relationship from the positive electrode; an electrolyte in said housing in contact with said positive and negative electrodes; a gas space within said housing in which oxygen and hydrogen gas collects; a pressure relief valve which allows gas to escape from the housing and which prevents oxygen gas from outside the housing from entering said housing; a catalyst device which includes a container having a container wall and which defines an internal chamber, said catalyst device including a catalyst arranged within said internal chamber and which is capable of reacting oxygen gas and hydrogen gas to form water vapor, said catalyst device being arranged such that said catalyst is in fluid communication with said gas space and isolated from said oxygen gas outside of said housing; and a micro-porous section having pores through which said oxygen gas and hydrogen gas can pass into said internal chamber from outside of said container, said micro-porous section being capable of preventing liquid water from passing there through, said device being configured such that all fluid communication between said outside of said internal chamber and said internal chamber is by passage through said micro-porous section; and wherein at least one of the pore size, planar surface area and thickness of said micro-porous section is selected to control the amount or rate at which said oxygen and hydrogen gases can pass into said internal chamber to control the heat generated by the catalytic combination of said oxygen and hydrogen gases.