Catalyst design for VRLA batteries

A device for combining gases in a storage battery;

• comprising:
• a catalyst container having an internal chamber and an opening to said chamber, said container being substantially non-porous;
• a catalyst arranged within said chamber, said catalyst capable of reacting oxygen gas and hydrogen gas;
• a catalyst poison filter arranged within said chamber;
• and
• a micro-porous hydrophobic member arranged to seal said opening, said micro-porous member having pores of suitable size to permit gas to pass there through while being a barrier to liquids.

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 vent which allows gas to escape from the housing and which prevents oxygen gas from outside the housing to contact said negative electrode;
• a catalyst device arranged to be in contact with at least a portion of said oxygen and hydrogen gas, said device including a container having a container wall and defining an internal chamber, and a catalyst arranged within said chamber, said catalyst capable of reacting oxygen gas and hydrogen gas to form water vapor;
• and
• a catalyst poison filter arranged to be in contact with at least a portion of said oxygen and hydrogen gas.

A catalyst container for use in battery cells having an electrolyte, said container comprising:

• a container wall comprising a plastic material;
• a chamber within said container capable of holding catalyst;
• and
• a flange attached to said container.

In a method for charging a valve-regulated, lead-acid (VRLA) cell at a charge voltage which has a value that is slightly in excess of the value of the open-circuit voltage of the cell, said cell including, in spaced relationship, a positive electrode and a negative electrode, and sandwiched therebetween electrolyte-containing separator means in which electrolyte is contained, wherein, during charging of the cell, there is produced at the positive and negative electrodes respectively oxygen gas and hydrogen gas in a predetermined amount, a portion of the oxygen gas tending to migrate through the electrolyte-containing separator means to the negative electrode and cause depolarization thereof, wherein there is also formed at the positive electrode hydrogen ions which migrate to the negative electrode to form hydrogen gas in an amount less than said predetermined amount, the negative electrode tending to discharge over a prolonged period of time during charging, wherein the tendency of the negative electrode to discharge during charging in inhibited by controlling the amount of oxygen gas in the cell by catalytically converting a portion of the oxygen gas and a portion of the predetermined amount of hydrogen gas to water, and wherein during said catalytic conversion there is a tendency for the reaction to generate heat which affects adversely the operation of the cell, the improvement comprising controlling the reaction to inhibit the generation of excess heat by controlling the amounts of oxygen gas and hydrogen gas that are contacted with the catalyst.