CLIAMS:I claim:
1) A recombination vent plug for a battery comprising;
a) a ceramic honeycomb substrate coated with a catalyst for the recombination of gases wherein the catalysts are in ionized form;
b) a housing with a plurality of passages, wherein a first passage holds the honey comb substrate and allows the gases released from a battery cell to pass through; and
c) a dome shaped casing disposed on top of the honey comb substrate for water condensation wherein the condensed water molecules flows down into the battery cell through a second passage of the housing.
2) The recombination vent plug, as claimed in claim 1, wherein said honeycomb substrate has plurality of holes to increase the contact surface area for gases to recombine.
3) The recombination vent plug, as claimed in claim 1, wherein said honeycomb substrate is made of a silica or alumina based ceramic body.
4) The recombination vent plug, as claimed in claim 1, wherein said catalysts are noble metal nano-crystalline ionized salts.
5) The recombination vent plug, as claimed in claim 1, wherein said housing made of a molded thermo plastic material.
6) The recombination vent plug, as claimed in claim 1, wherein said plastic material are made of at least one of a polypropylene PP or high impact polystyrene.
,TagSPECI:[001] Description of the invention
[002] The following specification particularly describes the invention and the manner in which it is to be performed
[003] Technical field of the invention
[004] The present invention relates to a recombination vent plug for secondary rechargeable cells & batteries. In particular, the present invention relates to the recombination vent plug in which water is regenerated by recombination of hydrogen and oxygen gases. The water vapor condenses into small water droplets obtained during recombination of gases and delivering the water molecules back into the battery cell.
[005] Background of the invention
[006] Most rechargeable batteries such as Lead acid, nickel-cadmium or nickel-iron batteries with flooded acid or excess electrolyte are probable to work for long life of 8 to 12 years. Several catalysts have been tried and tested for various industrial applications including nuclear energy reactors for recombination of hydrogen and oxygen gases. Problem of water loss due to electrolysis is inherent property of a dynamic system where battery is connected to an electrical system, e.g. emergency lighting system, inverter, uninterruptable power supply, power generating stations, power sub-stations, telecommunication exchanges or solar photovoltaic systems etc.
[007] Maintaining the water level is the maintenance aspect of every battery system such as lead acid batteries when installed for various applications. The battery life is dependent on maintenance of sufficient water level throughout its functioning.
[008] During working of such batteries under float or float-cum-boost condition on standby application, there is loss of water due to the electrolysis as well as natural evaporation due to high ambient temperature condition. Thus for sustainability of the battery, it is required to maintain the water level by addition of de-mineralized water at regular intervals. Many times batteries may be located in remote areas where maintenance of batteries in a given system is challenging task. The system may fail to perform when the water level drops and the battery plates get sulphated. Premature system failure can cause data loss, application break down and may have cascading effect on the integrated systems.
[009] Thus there is need for a recombination vent plug that reduces the maintenance and loss of water.
[0010] Summary of the invention
[0011] According to embodiment, the invention discloses a recombination vent plug for a rechargeable secondary battery. The recombination vent plug includes a honeycomb substrate coated with a catalyst for the recombination of gases. The catalysts are in ionized form. The recombination vent plug also includes housing with a number of passages. A first passage holds the honey comb substrate and allows the gases coming from a battery cell to pass through it. The recombination vent plug also includes a dome shaped casing over the honey comb substrate for water condensation. The condensed water molecules from the dome shaped casing flow down to the battery cell through a second passage of the housing.
[0012] According to an embodiment honeycomb substrate has plurality of holes to increase the contact surface area for gases to recombine.
[0013] The present invention eliminates routine maintenance, visit of technicians to site by maintaining the water level. It also reduces the water loss during electrolysis. Thus the invention gives a maintenance free operation and provides long life to the batteries. No corrosion to the parts in the vicinity of the system or contact resistance is built up
[0014] Brief description of the drawings
[0015] The foregoing and other features of embodiments will become more apparent from the following detailed description of embodiments when read in conjunction with the accompanying drawing. In a drawing, like reference numerals refer to like elements.
[0016] FIG 1 shows the cross-sectional view of recombination vent plug for a battery in accordance with an embodiment of the invention.
[0017] FIG 2 shows the front view of the recombination vent plug mounted on the battery cell.
[0018] Detailed description of the invention
[0019] Reference will now be made in detail to the description of the present subject matter, one or more examples of which are shown in figures. Each example is provided to explain the subject matter and not a limitation. Various changes and modifications obvious to one skilled in the art to which the invention pertains are deemed to be within the spirit, scope and contemplation of the invention.
[0020] The invention discloses a recombination vent plug for a secondary rechargeable cell or battery. The recombination vent plug includes a honeycomb substrate coated with a catalyst for the recombination of gases. The recombination vent plug also includes housing with a number of passages. A first passage holds the honey comb substrate and allows the gases coming from a battery cell to pass through it. The recombination vent plug also includes a dome shaped casing which is of a wavy umbrella shaped design over the honey comb substrate for water condensation. The condensed water molecules from the dome shaped casing flow down to the battery cell through a second passage of the housing. The batter may be a lead-acid battery.
[0021] FIG 1 shows the cross-sectional view of recombination vent plug for a battery in accordance with an embodiment of the invention. The recombination vent plug (100) includes a honeycomb substrate (101) coated with a catalyst for the recombination of gases. The catalysts are in ionized form. The recombination vent plug (100) also includes housing (102) with a number of passages. A first passage (103) holds the honeycomb substrate (101) and allows the gases (106) released from a battery cell (110) to pass through it. The recombination vent plug (100) also includes a dome shaped casing (104) over the honey comb substrate (101) for water condensation. The condensed water molecules (107) from the dome shaped casing (104) flow down to the battery cell through a second passage (105) of the housing (102). The direction of flow of condensed water molecules (107) to the battery cell (110) is represented using the arrows 108, 109. The gases (106) coming through first passage (103) come in contact with the honeycomb substrate (101) coated with the catalyst as soon they are released from the battery cell (110). On exposure to the catalyst surface, recombination reaction takes place and water vapor produced is allowed to condense on the dome shaped casing (104). The condensation of the water molecules (107) takes place on the dome shaped casing (104) and the condensed water flows down due to gravity through the second passage (105) and enter back into the battery cell (110).
[0022] According to an embodiment, the honeycomb substrate (101) has numerous holes to increase the contact surface area for gases (106) to recombine. For example the honeycomb substrate (101) may have minimum 400 holes / inch2 area. The presence of holes provides larger contact surface area and provides high reaction efficiency for gases (106) to combine. The honeycomb substrate (101) is made of silica or alumina based ceramic body. The catalyst coated on the honeycomb substrate (106) is noble metal nano-crystalline ionized salts. The catalyst is coated in micron layer on the honeycomb surface (101).
[0023] According to an embodiment, the metal nano-crystalline salts include platinum salt or oxide and palladium salts. The platinum salt or oxide has good efficiency at low ambient temperatures (<35 degree Celsius). But at higher temperature, efficiency is reduced. Whereas the palladium salts functions efficiently at high ambient temperature (> 35 degree Celsius). The combination of both platinum and palladium salts in ionized form is used as the catalyst which enables the catalyst to work efficiently on batteries at any site / ambient temp. This catalyst is unaffected by water vapor saturation, which eliminates the poisoning. The above combination of catalyst produces greater recombination efficiency as the catalyst function at wide range of temperatures.
[0024] According to most preferred embodiment, the housing (102) is made of a molded thermo plastic material. The plastic material includes one or more of a polypropylene PP or high impact polystyrene.
[0025] The structural design of the present invention allows gases (106) released from first passage (103) from the battery cell (110) to come in contact with the catalyst present on the honeycomb substrate (101) as soon the gases (106) are released from battery cell through the first passage (103). By recombination reaction water molecules (107) are regenerated which condense on the inner surface of the dome shaped casing (104) placed above the honeycomb substrate (101). The water molecules (107) on condensation flow down due to gravity through the side wall and enter back into the battery cell (110) through the second passage (105). The passages of the housing (102) is constructed in such a way that the passages are separated by internal design of plastic components thermo-plastic material such as polypropylene PP or high impact polystyrene. Thus the passage of gases (106) releasing out from the battery cell and return path of condensed water molecules (107), are separated.
[0026] Water level inside the battery cell (110) is thus maintained all the time, corrosive Sulphuric acid fumes are not carried outside the battery cell, it reduces ventilation of room as well as preventing routine maintenance of battery.
[0027] The present invention virtually eliminates the corrosion of terminals caused due to acid mist of the battery and thus reduces contact resistance which improves charge acceptance of battery.
[0028] In the present invention the recombination of vent plug is suitably designed for various standard specifications and can be placed on any make of lead acid, nickel-cadmium or nickel-iron alkaline battery.
[0029] It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
[0030] Example 1.
Working of recombination plug with battery over charge:
(As in the attached document)
Example 2. Effect of ambient temperature on working of recombination rate
Float current in Ampere 0.03
(As in the attached document)