DESC:FIELD OF THE INVENTION:
The present invention relates to a lead-acid battery with a heat management and dissipation system for producing high purity hydrogen and oxygen gases. Moreover, this invention uses a lead-acid cell in which positive and negative electrodes are immersed in an electrolyte and these electrodes are separated by a separator.

BACKGROUND OF THE INVENTION:
Hydrogen with its clean combustion and versatile applications across various sectors, emerges as a promising alternative to conventional fossil fuels. As the world transitions towards sustainable energy sources to mitigate climate change and achieve energy security, hydrogen stands out as a promising source of clean energy.

Hydrogen can be produced through various methods, including steam methane reforming, electrolysis, biomass gasification, and solar-driven processes. Among these, electrolysis, powered by renewable energy sources like solar and wind, offers a sustainable pathway to produce 'green hydrogen.' This method involves splitting water molecules into hydrogen and oxygen using electricity, emitting no greenhouse gases in the process.

Hydrogen has a wide range of applications across various sectors. In transportation, fuel cell vehicles (FCVs) offer zero-emission mobility, with hydrogen fuel cells converting hydrogen gas into electricity to power the vehicle's motor, emitting only water vapor as a byproduct. Additionally, hydrogen can be blended with natural gas (HCNG etc) for heating and transportation, reducing carbon emissions.

Presently, electrolysis of water to produce hydrogen from an electrolyzer using green energy sources has potential. Few of the prior arts are discussed below.

US patent number 9181624B2 disclosed a method for producing Chlorine and Oxygen gases using alkali electrolyte electrolysis.

US patent number 10297890 B2 disclosed a method for producing Chlorine, Hydrogen and Oxygen gases using alkali electrolyte electrolysis.

US patent number 10297890 B2 disclosed a method of producing Hydrogen and Oxygen from Nickel-Iron battery.

US 2022/0074059 Al disclosed a method of producing Hydrogen and Oxygen from Nickel-Iron battery.

US 11552352 B2 disclosed a method of producing Hydrogen and Oxygen from Nickel-Iron battery.

However, despite its potential, the widespread adoption of electrolyzers faces several challenges. Major hurdles are the high cost of production, electrolyzer working life, low hydrogen and oxygen volume production, and supply of deionized water. Hence, there is an economic alternative to electrolyzer based hydrogen production.

SUMMARY OF THE INVENTION:
This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention, nor is it intended to determine the scope of the invention.

The present invention provides a lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises a lead-acid cell comprising a battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, and an electrolyte level indicator, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof; a thermally conductive heat sink; and an enclosure comprising a heat management system, wherein the lead-acid cell and the thermally conductive heat sink are placed inside the enclosure, the thermally conductive heat sink absorbs heat from the lead-acid cell and transfers the heat to the enclosure, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

The present invention also provides a lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises a plurality of lead-acid cells connected in series, wherein each of the lead-acid cells comprises a battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, an electrolyte level indicator, and a temperature indicator, wherein the hydrogen collection nozzle is connected to hydrogen header line, and the oxygen collection nozzle is connected to an oxygen header line, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof; a thermally conductive heat sink comprising a liquid circulation system, wherein the liquid circulation system absorbs heat from the plurality of lead-acid cells, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

The present invention also provides a lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises a plurality of lead-acid cells connected in series, wherein each of the lead-acid cells comprises a battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, an electrolyte level indicator, and a temperature indicator, wherein the hydrogen collection nozzle is connected to hydrogen header line, and the oxygen collection nozzle is connected to an oxygen header line, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof; and a thermally conductive heat sink comprising an electrolyte circulation system, wherein the electrolyte circulation system absorbs heat from the plurality of lead-acid cells, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

The present invention further provides a lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises a plurality of lead-acid cells connected in series, wherein each of the lead-acid cells comprises a battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, an electrolyte level indicator, and a temperature indicator, wherein the hydrogen collection nozzle is connected to hydrogen header line, and the oxygen collection nozzle is connected to an oxygen header line, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof; a thermally conductive heat sink selected from a group comprising an end plate placed at side walls of the battery cell body of the lead-acid cell, a liquid circulation system, and an electrolyte circulation system, wherein the thermally conductive heat sink absorbs heat from the lead-acid cell, the positive electrode and the negative electrode of the battery cell are placed inside the battery cell body, the lead-acid cell comprises a separator placed between the positive electrode and the negative electrode of the lead-acid cell dividing the lead-acid cell into a positive half-cell and a negative half-cell, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

OBJECTIVE OF THE INVENTION:
The primary objective of the present invention is to provide a lead-acid battery for producing high purity hydrogen and oxygen gases through water splitting reactions.

Another objective of the present invention is to provide a lead-acid battery with heat management and dissipation system for producing high purity hydrogen and oxygen gases.

Another objective of the present invention is to provide a lead-acid battery for producing high purity hydrogen and oxygen gases by in-situ separation in the lead-acid cell.

Another objective of the invention is to provide a lead-acid battery as an economic alternative to electrolyzer for high purity hydrogen production.

Another objective of the invention is to provide a lead-acid battery for producing high purity hydrogen and oxygen gases, wherein the cathode of the lead-acid cell consists of Pb and carbon nanotubes (CNT) as an additive, the anode of the lead-acid cell consist of PbO2 and carbon nanotubes (CNT) as an additive, and dilute sulfuric acid as electrolyte.

BRIEF DESCRIPTION OF THE DRAWING:
The detailed description below will be better understood when read in conjunction with the appended drawings. For the purpose of assisting in the explanation of the invention, there are shown in the drawings embodiments which are presently considered illustrative. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown therein. The invention will now be described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 depicts a lead-acid battery to produce high purity hydrogen and oxygen gases using renewable energy sources and its applications.
Figure 2 depicts a lead-acid battery comprising a lead-acid cell with thermally conductive heat sink and an enclosure with a cooling fan and an exhaust fan.
Figure 3 depict a lead-acid battery comprising a plurality of lead-acid cells connected in series with thermally conductive heat sink and an enclosure with a cooling fan and an exhaust fan.
Figure 4 depicts a lead-acid battery comprising a plurality of lead-acid cells connected in series with water circulation system and an enclosure with a cooling fan and an exhaust fan.
Figure 5 depicts the separator design and positive and negative half cells.
Figure 6 depicts a lead acid battery comprising a plurality of lead-acid cells connected in series with electrolyte circulation system and an enclosure with a cooling fan and an exhaust fan.

DETAILED DESCRIPTION OF THE INVENTION:
Hydrogen can be produced through various methods, including steam methane reforming, electrolysis, biomass gasification, and solar-driven processes. Among these, electrolysis, powered by renewable energy sources like solar and wind, offers a sustainable pathway to produce 'green hydrogen'.

The present invention discloses a lead-acid battery to produce high purity hydrogen and oxygen gases using renewable energy sources as shown in Figure: 1.

The present invention provides a lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises:
? a lead-acid cell comprising a battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, and an electrolyte level indicator, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof;
? a thermally conductive heat sink; and
? an enclosure comprising a heat management system, wherein the lead-acid cell and the thermally conductive heat sink are placed inside the enclosure, the thermally conductive heat sink absorbs heat from the lead-acid cell and transfers the heat to the enclosure, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

In an embodiment of the present invention, the thermally conductive heat sink comprises an end plate placed at the side walls of the battery cell body of the lead-acid cell and the end plate is in direct contact with the electrolyte, the end plate is acid resistant and made of a thermally conductive polymer composite. This composite has higher electrical and thermal conductivity than most metals and is non-reactive to acid. In addition, this composite can be manufactured to the required shape and dimensions to fit the cell end plate.

In an embodiment of the present invention, the thermal management system comprises a cooling fan and an exhaust fan placed over vertical sides of the enclosure, wherein the exhaust fan dissipates the heat from the enclosure and the cooling fan cools down the enclosure.

Lead acid battery, during its charging, converts lead sulfate (PbSO4) to active material lead (Pb) and lead oxide (PbO2). However, during its continuous charging (overcharging), excess electricity is being used to split water into Hydrogen and Oxygen gases. So, overcharging of the battery results in the production of hydrogen gas. Therefore, in the process of producing Hydrogen gas, the battery gets heated up and this heat needs to be removed for material integrity and safe operation. In this aspect, a heat sink and fans are installed on both sides of the cell to dissipate the heat from the heat sink through convection as shown in Figure 2.

In an embodiment of the present invention, the lead-acid battery cell (2) is placed inside the enclosure (1). Excess heat inside the battery is removed using the thermally conductive heat sink (4). This end plate placed at the side walls of the lead-acid cell act as thermally conductive heat sink which is acid resistant in nature and is directly in contact with the electrolyte. An exhaust fan (5) is placed over the vertical sides of the enclosure, which removes the heat from the enclosure. Due to continuous heat removal from the enclosure, heat is taken out from the thermally conductive heat sink and eventually the temperature of lead-acid cell comes down. In the present cell, electrolyte (3) works as ions carrier for both half cells and its temperature is also measured to check the performance of thermally conductive heat sink. As electrolyte is a crucial part of hydrogen production and is also primary medium to absorb the heat, its level should be maintained. Hence, an electrolyte level indicator is used for this purpose. Electrodes terminals (6) and (7) are taken out from the enclosure to provide electrical connection. Hydrogen and Oxygen gases are collected through a hydrogen collection nozzle (8) and an oxygen collection nozzle (9) respectively. Collected Hydrogen is further purified to use it for fuel cell applications like transportation.

In an embodiment of the present invention, the lead-acid battery comprises a plurality of lead-acid cells connected in series, wherein the hydrogen collection nozzle is connected to hydrogen header line, and the oxygen collection nozzle is connected to an oxygen header line, wherein the hydrogen header line is connected to a gas booster to increase the pressure to 8 bar.

One more embodiment of the present invention discloses the series arrangement of the plurality of lead-acid cells which is given in Figure: 3. The plurality of lead-acid cells (11) are connected in a series (14) which increases the cumulative hydrogen production. All the cells are placed in the enclosure (10) for better cooling. The plurality of lead-acid cells are arranged in a way that a common cooling fan (12) and exhaust fan (13) for all cells. Each cell gas line is connected to a header line and are connected to gas booster to increase the pressure of gas. Hydrogen header line (15) is connected to gas booster to increase the pressure to 8 bar. At this pressure the gas can be used for cooking and commercial heating applications. Oxygen header line (16) can be pressurized and stored for commercial applications.

The present invention also provides a lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises:
? a plurality of lead-acid cells connected in series, wherein each of the lead-acid cells comprises a battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, an electrolyte level indicator, and a temperature indicator, wherein the hydrogen collection nozzle is connected to hydrogen header line, and the oxygen collection nozzle is connected to an oxygen header line, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof; and
? a thermally conductive heat sink comprising a liquid circulation system;
? wherein the liquid circulation system absorbs heat from the plurality of lead-acid cells, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

In an embodiment of the present invention, the liquid circulation system consists of a cooling medium passing through the lead-acid battery, a cooling medium inlet and a cooling medium outlet connected to each of the plurality of lead-acid cells to pass the cooling medium.

In an embodiment of the present invention, the cooling medium is water.

One more embodiment of the present invention discloses the plurality of lead-acid cells, and their electrolyte is cooled using a liquid circulation system which is given in Figure: 4. The plurality of lead-acid cells (11) are connected in a series (14) arrangement which increases the cumulative hydrogen production. The temperature of each is controlled by exchanging the heat with a cooling medium like water. Initially, there is a water inlet (17) in the first cell and its outlet is connected to the adjacent cell and finally there is a cooling water outlet (18) from the last cell.

The present invention also provides a lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises:
? a plurality of lead-acid cells connected in series, wherein each of the lead-acid cells comprises a battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, an electrolyte level indicator, and a temperature indicator, wherein the hydrogen collection nozzle is connected to hydrogen header line, and the oxygen collection nozzle is connected to an oxygen header line, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof; and
? a thermally conductive heat sink comprising an electrolyte circulation system, and
wherein the electrolyte circulation system absorbs heat from the plurality of lead-acid cells, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

In an embodiment of the present invention, the electrolyte circulation system comprises an electrolyte tank containing a cold electrolyte, a circulation pump for the circulation and exchange of a cold electrolyte from electrolyte tank with the electrolyte of the lead-acid battery cell, and a radiator connected to the electrolyte tank for the removal of heat from the electrolyte tank.

In an embodiment of the present invention, the temperature of the electrolyte is maintained below 50 ?.

The present invention also provides a lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises:
? a plurality of lead-acid cells connected in series, wherein each of the lead-acid cells comprises a battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, an electrolyte level indicator, and a temperature indicator, wherein the hydrogen collection nozzle is connected to hydrogen header line, and the oxygen collection nozzle is connected to an oxygen header line, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof; and
? a thermally conductive heat sink selected from a group comprising an end plate placed at side walls of the battery cell body of each of the plurality of lead-acid cells, a liquid circulation system, and an electrolyte circulation system;
? wherein the thermally conductive heat sink absorbs heat from the lead-acid cell,
the positive electrode and the negative electrode of the battery cell are placed inside the battery cell body, the lead-acid cell comprises a separator placed between the positive electrode and the negative electrode of the lead-acid cell dividing the lead-acid cell into a positive half-cell and a negative half-cell, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

In an embodiment of the present invention, the thermally conductive heat sink comprises an end plate placed at side walls of the battery cell body of each of the plurality of lead-acid cells, and a liquid circulation system.

In another embodiment of the present invention, the thermally conductive heat sink comprises an end plate placed at side walls of the battery cell body of each of the plurality of lead-acid cells, and an electrolyte circulation system.

In one or more embodiments of the present invention, the battery cell body is made of polypropylene.

In an embodiment of the present invention, the separator is porous in nature and has openings at bottom, wherein positive half-cell and the negative half-cell is provided with a positive and negative electrolyte indicator respectively, and a positive and negative electrolyte top up nozzle respectively, wherein the temperature indicator comprises a thermocouple inserted into the positive half-cell and the negative half-cell.
The present invention explains the in-situ separation of hydrogen and oxygen gases. The lead-acid cell consists of two half cells and are separated by a modified separator which decreases the potential of cell and separates the hydrogen and oxygen gases by isolating the electrolyte present in each half cell. This separator only separates the gases, but the ionic movement will take place through the pores of the separator.

One or more embodiment of the present invention provides the thermally conductive heat sink comprises an end plate placed at side walls of the battery cell body of each of the plurality of lead-acid cells, the end plate of each of the plurality of lead-acid cells is in direct contact with the electrolyte, the end plate is acid resistant and made of a thermally conductive polymer composite.

One or more embodiment of the present invention provides, the plurality of lead-acid cell and the thermally conductive heat sink selected from a group comprising an end plate placed at side walls of the battery cell body of each of the plurality of the lead-acid cells, a liquid circulation system, and an electrolyte circulation system are place inside an enclosure or a cabinet, wherein the enclosure comprises a heat management system, and wherein the thermally conductive heat sink absorbs heat from the lead-acid cell and transfers the heat to the enclosure.

One or more embodiment of the present invention provides the thermal management system comprises a cooling fan and an exhaust fan placed over vertical sides of the enclosure inside which the plurality of lead-acid cells are placed, wherein the exhaust fan dissipates the heat from the enclosure and the cooling fan cools down the enclosure.

One more embodiment of the present invention discloses the design of the separator (32) which is given in Figure 5. The separator (32) is placed between two half cells made with polypropylene battery cell body (19). The end plates made of thermally conductive polymer composite comprises polypropylene plates (19a) placed at the side walls of the battery cell body, directly in contact with the electrolyte. The polypropylene battery cell body holds the positive (20) and negative (21) electrodes and their positive (26) and negative (27) terminals will be taken out for connection. The separator used in the present invention is porous in nature and can isolate the gas from either side of the cell. But 100% isolation by separator increases the internal resistance of the cell. In view of this, an opening (34) is made at the bottom of the separator where the electrodes will not see their faces so there is no gas production and mixing. In addition, this opening also helps in the movement of ions and decreases the internal resistance. Above this opening the electrodes start to see their faces so complete isolation with separator is required to avoid intermixing. The projection of electrode face (33) on separator is shown in Figure 5. During charging, the hydrogen and oxygen gases will be produced and will escape from the electrolyte quickly from hydrogen (29) and oxygen (24) nozzles. For each one mole of hydrogen production, equal moles of water will be lost so electrolyte level monitoring is crucial. In view of this, a positive (25) and negative (28) level indicators are provided. The drop in level is topped up to actual level with water in both half cells through positive (22) and negative (31) water top up nozzles. The positive and negative half-cell electrolyte temperature is measured by inserting a thermocouple in the positive (23) and negative (30) thermowell respectively.

One more embodiment of the present invention discloses the thermal management of the plurality of lead-acid cells using electrolyte circulation system which is shown in Figure: 6. During charging as the time progresses the temperature of each cell will increase so an electrolyte circulation option is adopted. The hot electrolyte (36) from each cell will be sent to the electrolyte tank (38) where it mixes with the cold electrolyte. The heat from electrolyte tank is removed through radiator. The cooled electrolyte (35) is sent back to the cell using circulation pump (37). The circulation of this electrolyte is a continuous process so the temperature of electrolyte will be maintained below 50 ?.

One more embodiment of the present invention discloses the positive electrode comprises Pb and carbon nanotubes (CNT) as the additive, the negative electrode comprises PbO2 and CNT as the additive, and wherein the electrolyte is dilute sulfuric acid. CNTs are highly electrically conductive and are used in positive and negative plate preparation to reduce the internal resistance. In addition, carbon nanotubes are added to reduce the over potential of the lead-acid battery thus the operating potential is minimized. It correspondingly correlated to power requirement for water splitting reaction.

One more embodiment of the present invention is the use of tubular plates for both negative and positive electrodes. As any hydrogen application in the present invention doesn’t involve the high rate of discharge (HRD) so the flat negative plate can be replaced with a tubular negative plate and is a good option to increase the life. The tubular plate option positive and negative electrodes will increase the mechanical stability even in hot conditions of cell.

One more embodiment of the present invention provides that all components of the cells are 100% recycled at the end of the life cycle. If the mechanical integrity of the cell is intact, only the electrodes are corroded and mechanical integrity is lost, the electrodes can be replaced and use the remaining components for further use. This way, the overall capital cost for the next set of batteries is drastically decreased.

One more embodiment of the present invention provides that the end-of-life lead acid cells can be used for hydrogen and oxygen production. As the end-of-life cells don’t give much of discharge capacity, these can be used for hydrogen production.

EXAMPLES:
The present disclosure with reference to the accompanying examples describes the present invention. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention. It is understood that the examples are provided for the purpose of illustrating the invention only and are not intended to limit the scope of the invention in any way.

Example: 1
The working voltage of lead-acid cell for hydrogen production starts from ~2.6V which is higher than a PEM electrolyser. Due to this the operating cost for lead-acid cells will increase. In this regard, CNT nanomaterial is incorporated into the active material preparation of negative and positive plates. CNT is an electrically and thermally conductive additive and will inhibit the growth of lead sulphate crystals in electrodes and acts as a conductive medium between the non-conductive lead sulphate crystals. These characteristics are also observed in the formation/charging curve of this lead acid cell. In the formation curve, the Ah to reach Top Charge Voltage (TOCV) is delayed and TOCV is also lesser than the non-CNT (control) cell. This way, CNT is a suitable material for hydrogen production. This additive also doesn’t require additional preparation steps for electrode preparation. Thus, the operating and capital cost will not change for the industries.

Table 1: TOCV for control and CNT lead acid cell.
TOCV
Control CNT % Reduction
2.7 2.55 6

Example 2:
Polypropylene plates are fabricated as per the design dimension and nozzle requirements. Positive and negative tubular plates will be installed in the polypropylene plates with minimum gap to achieve the least resistance. Then, polypropylene plates with positive and negative tubular plates are assembled with separator in between. Highly thermally conductive heat sinks will be installed on both sides of the cell to dissipate the heat from cell. Afterwards, all the nozzles for hydrogen, oxygen, water top up and thermocouple are installed. Then all the ten cells are filled with 1.2 sp gr sulfuric acid and are connected in series to achieve an open circuit voltage of 20V. Finally, all ten cells are kept in a cabinet and is provided with fans. Initially, 30A of current is passed through the battery, a cumulative flowrate of 13.39g/h of gas is produced in which 99.9% will be hydrogen. The production rate of hydrogen is linear to the supplied current.

Table 2: Hydrogen gas production rate with current
S.No. Current, amp Voltage, V Duration, h Cell temperature, °C Hydrogen Flow rate, g/h Total hydrogen, g
1 30 31 24 48 13.39 321
2 45 33 24 50 20.09 482
3 60 35 24 55 26.79 643

Table 3: Hydrogen gas purity Table 4: Oxygen gas purity
S.No. Gas Composition, Vol% S.No. Gas Composition, Vol%
1 Hydrogen 99.9 1 Oxygen 99.9
3 Oxygen 0.0995 3 Hydrogen 0.0995
2 Nitrogen 0.0005 2 Nitrogen 0.0005

During hydrogen production, the temperature of each cell is measured to observe the working efficiency of the heat sink. Even though temperature above room temperature favors the water splitting but is detrimental to the mechanical stability of electrodes. In this regard, all ten cells are kept in a cabinet and is provided with cooling and exhaust fans for better cooling. After the end of cycle, all the components can be recycled including the electrodes so the overall capital cost for the cell will be drastically reduced compared to any electrolyzer.

Example :2
Polypropylene plates are fabricated as per the design dimension and nozzle requirements. Positive and negative tubular plates will be installed in the polypropylene plates with minimum gap to achieve the least resistance. A heat exchange tube will be installed on both sides of the cell to dissipate the heat from cell. Then, polypropylene plates with positive and negative tubular plates are assembled with separator in between. Afterwards, all the nozzles for hydrogen, oxygen, water top up and thermocouple are installed. Then all the ten cells are filled with 1.2 sp gr sulfuric acid and are connected in series to achieve an open circuit voltage of 20V. Finally, all ten cells are provided with water circulation in each cell. Initially, 30A of current is passed through the battery, a cumulative flowrate of 13.39g/h of gas is produced in which 99.9% will be hydrogen. The production rate of hydrogen is linear to the supplied current.

Table 5: Hydrogen gas production rate with current
S.No. Current, amp Voltage, V Duration, h Cell temperature, °C Hydrogen Flow rate, g/h Total hydrogen, g
1 30 31 24 38 13.39 321
2 45 33 24 40 49 20.09 482
3 60 35 24 43 52 26.79 643

Table 6: Hydrogen gas purity Table 7: Oxygen gas purity
S.No. Gas Composition, Vol% S.No. Gas Composition, Vol%
1 Hydrogen 99.9 1 Oxygen 99.9
3 Oxygen 0.0995 3 Hydrogen 0.0995
2 Nitrogen 0.0005 2 Nitrogen 0.0005

During hydrogen production, the temperature of each cell is measured to observe the working efficiency of the heat exchanger. Even though temperature above room temperature favors the water splitting but is detrimental to the mechanical stability of electrodes. In this regard, all ten cells are kept in a cabinet and is provided with cooling and exhaust fans for better cooling. After the end of cycle, all the components can be recycled including the electrodes so the overall capital cost for the cell will be drastically reduced compared to any electrolyzer.

Example :3
Polypropylene plates are fabricated as per the design dimension and nozzle requirements. Positive and negative tubular plates will be installed in the polypropylene plates with minimum gap to achieve the least resistance. An electrolyte circulating nozzle will be installed on both sides of the cell to dissipate the heat from the cell. Then, polypropylene plates with positive and negative tubular plates are assembled with separator in between. Afterwards, all the nozzles for hydrogen, oxygen, water top up and thermocouple are installed. Then all the ten cells are filled with 1.2 sp gr sulfuric acid and are connected in series to achieve an open circuit voltage of 20V. Finally, all ten cells are provided with an electrolyte circulation connection to the electrolyte sink to dissipate the heat. Initially, 30A of current is passed through the battery, a cumulative flowrate of 13.39g/h of gas is produced in which 99.9% will be hydrogen. The production rate of hydrogen is linear to the supplied current.

Table 8: Hydrogen gas production rate with current
S.No. Current, amp Voltage, V Duration, h Cell temperature, °C Hydrogen Flow rate, g/h Total hydrogen, g
1 30 31 24 36 13.39 321
2 45 33 24 38 20.09 482
3 60 35 24 40 26.79 643

Table 9: Hydrogen gas purity Table 10: Oxygen gas purity
S.No. Gas Composition, Vol% S.No. Gas Composition, Vol%
1 Hydrogen 99.9 1 Oxygen 99.9
3 Oxygen 0.0995 3 Hydrogen 0.0995
2 Nitrogen 0.0005 2 Nitrogen 0.0005

During hydrogen production, the temperature of each cell is measured to observe the working efficiency of the electrolyte circulation. Even though temperature above room temperature favors the water splitting but is detrimental to the mechanical stability of electrodes. In this regard, all ten cells are kept in a cabinet and is provided with cooling and exhaust fans for better cooling. After the end of cycle, all the components can be recycled including the electrodes so the overall capital cost for the cell will be drastically reduced compared to any electrolyzer.

Reference numbers
1: Enclosure, 2: Single lead-acid cell, 3: Electrolyte, 4: Thermally conductive heat sink-end plates, 5: fan, 6: Positive electrode terminal connection, 7: Negative electrode terminal connection, 8: Oxygen collection nozzle, 9: Hydrogen collection nozzle, 10: Battery series cells enclosure, 11: Single battery cell in series connection, 12: Cooling fan, 13: Exhaust fan, 14: Series terminal connections, 15: Oxygen header line, 16: Hydrogen header line, 17: Cooling Water inlet, 18: Cooling water outlet, 19: Battery cell body made of Polypropylene, 19a: Side walls of battery cell body, 20: Positive Plate, 21: Negative Plate, 22: Positive side water top up nozzle, 23: Positive plate Thermocouple well, 24: Oxygen gas nozzle, 25: Positive electrode electrolyte level indicator, 26: Positive terminal, 27: Negative terminal, 28: Negative electrode electrolyte level indicator, 29: Hydrogen gas nozzle, 30: Negative plate thermocouple well, 31: Negative side water top up nozzle, 32: Separator, 33: Electrode face projection, 34: Opening on separator.35: Cooled electrolyte, 36: Hot electrolyte, 37: Electrolyte circulation pump, 38: Electrolyte tank.
,CLAIMS:1. A lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises:
? a lead-acid cell comprising a battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, and an electrolyte level indicator, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof;
? a thermally conductive heat sink; and
? an enclosure comprising a heat management system,
wherein the lead-acid cell and the thermally conductive heat sink are placed inside the enclosure, the thermally conductive heat sink absorbs heat from the lead-acid cell and transfers the heat to the enclosure, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

2. The lead-acid battery as claimed in claim 1, wherein the thermally conductive heat sink comprises an end plate placed at the side walls of the battery cell body of the lead-acid cell and the end plate is in direct contact with the electrolyte, the end plate is acid resistant and made of a thermally conductive polymer composite.

3. The lead-acid battery as claimed in claim 1, wherein the thermal management system comprises a cooling fan and an exhaust fan placed over vertical sides of the enclosure, wherein the exhaust fan dissipates the heat from the enclosure and the cooling fan cools down the enclosure.

4. The lead-acid battery as claimed in claim 1, wherein the lead-acid battery comprises a plurality of lead-acid cells connected in series, wherein the hydrogen collection nozzle is connected to hydrogen header line, and the oxygen collection nozzle is connected to an oxygen header line, wherein the hydrogen header line is connected to a gas booster to increase the pressure to 8 bar.

5. A lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises:
? a plurality of lead-acid cells connected in series, wherein each of the lead-acid cells comprises, a battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, an electrolyte level indicator, and a temperature indicator, wherein the hydrogen collection nozzle is connected to hydrogen header line, and the oxygen collection nozzle is connected to an oxygen header line, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof; and
? a thermally conductive heat sink comprising a liquid circulation system,
wherein the liquid circulation system absorbs heat from the plurality of lead-acid cells, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

6. The lead-acid battery as claimed in claim 5, wherein the liquid circulation system consists of a cooling medium passing through the lead-acid battery, a cooling medium inlet and a cooling medium outlet connected to each of the plurality of lead-acid cells to pass the cooling medium.

7. The lead-acid battery as claimed in claim 6, wherein the cooling medium is water.

8. A lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises:
? a plurality of lead-acid cells connected in series, wherein each of the lead-acid cells comprises, a battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, an electrolyte level indicator, and a temperature indicator, wherein the hydrogen collection nozzle is connected to hydrogen header line, and the oxygen collection nozzle is connected to an oxygen header line, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof; and
? a thermally conductive heat sink comprising an electrolyte circulation system,
the electrolyte circulation system absorbs heat from the plurality of lead-acid cells, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

9. The lead-acid battery as claimed in claim 8, wherein the electrolyte circulation system comprises an electrolyte tank containing a cold electrolyte, a circulation pump for the circulation and exchange of a cold electrolyte from electrolyte tank with the electrolyte of the lead-acid battery cell, and a radiator connected to the electrolyte tank for the removal of heat from the electrolyte tank.

10. The lead-acid battery as claimed in claim 8, wherein the temperature of the electrolyte is maintained below 50 ?.

11. A lead-acid battery for producing hydrogen and oxygen, wherein the lead-acid battery comprises:
? a plurality of lead-acid cells connected in series, wherein each of the lead-acid cells comprises, battery cell body, a positive electrode, a negative electrode, an electrolyte, a hydrogen collection nozzle, an oxygen collection nozzle, an electrolyte level indicator, and a temperature indicator, wherein the hydrogen collection nozzle is connected to hydrogen header line, and the oxygen collection nozzle is connected to an oxygen header line, wherein the positive electrode and the negative electrode both are tubular plates made of Pb, PbO2, an additive, and a combination thereof; and
? a thermally conductive heat sink is selected from a group comprising an end plate placed at side walls of the battery cell body of each of the plurality of the lead-acid cell, a liquid circulation system, and an electrolyte circulation system,
wherein the thermally conductive heat sink absorbs heat from the lead-acid cell,
the positive electrode and the negative electrode of the lead-acid cell are placed inside the battery cell body, the lead-acid comprises a separator placed between the positive electrode and the negative electrode of the lead-acid cell dividing the lead-acid cell into a positive half-cell and a negative half-cell, and wherein the lead-acid battery produces 99.9 vol% hydrogen and 99.9 vol% oxygen.

12. The lead-acid battery as claimed in claim 11, wherein the separator is porous in nature and has openings at bottom, the positive half-cell and the negative half-cell is provided with a positive and negative electrolyte indicator respectively, and a positive and a negative electrolyte top up nozzle respectively, wherein the temperature indicator comprises a thermocouple inserted into the positive half-cell and the negative half-cell.

13. The lead-acid battery as claimed in claims 1-11, wherein the battery cell body is made of polypropylene.

14. The lead-acid battery as claimed in claims 1-13, wherein the positive electrode comprises Pb and carbon nanotubes (CNT) as the additive, the negative electrode comprises PbO2 and CNT as the additive, and wherein the electrolyte is dilute sulfuric acid.

15. The lead-acid battery as claimed in claims 5-13, wherein the thermally conductive heat sink comprises an end plate placed at side walls of the battery cell body of each of the plurality of lead-acid cells, the end plate of each of the plurality of lead-acid cells is in direct contact with the electrolyte, the end plate is acid resistant and made of a thermally conductive polymer composite.

16. The lead-acid battery as claimed in claims 5-13, wherein the plurality of lead-acid cells and the thermally conductive heat sink are placed inside the enclosure, the thermally conductive heat sink absorbs heat from the lead-acid cell and transfers the heat to the enclosure, wherein the thermal management system comprises a cooling fan and an exhaust fan placed over vertical sides of the enclosure, and wherein the exhaust fan dissipates the heat from the enclosure and the cooling fan cools down the enclosure.