Claims:We Claim:

1. An electrochemical device (100), comprising:
a stack of cells (102); and
a plurality of bipolar plates (104), wherein at least one bipolar plate (104) is placed between adjacent cells (102) in the stack of cells and each of the bipolar plate (104) comprises:
a first portion (202) having a first side (206A) and a second side (206B), wherein the first portion (202) comprises:
a fuel opening (208) formed on a center of the first portion (202) and fluidically in contact with the first side (206A) of the first portion (202) to provide a fuel to the first side (206A) of the first portion (202); and
at least one air channel (210) formed on the second side (206B) of the first portion (202) and fluidically in contact with the second side (206B) of the first portion (202) to provide air to the second side (206B) of the first portion (202); and
a quadrilateral shaped portion (204) formed around the first portion (202), wherein the quadrilateral shaped portion (204) comprises:
at least one exhaust opening (212) formed around the first portion (202) and fluidically connected to the first side (206A) and the second side (206B) of the first portion (202) to receive the fuel and air.

2. The electrochemical device (100) as claimed in claim 1, wherein the first portion (202) comprising a protrusion (302) formed on the circumference of the fuel opening (208), wherein the protrusion (302) is protruded towards the second side (206B) of the first portion (202) and adapted to fluidically isolate the fuel opening (208) from the second side (206B) of the first portion (202).

3. The electrochemical device (100) as claimed in claim 1, wherein the quadrilateral shaped portion (204) comprises at least one cut-out portion (304) formed on four sides of the quadrilateral shaped portion (204).

4. The electrochemical device (100) as claimed in claim 3, wherein the cut-out portion (304) is a semi-circular portion having at least one second channel (306), wherein the second channel (306) is in-line to the air channel (210) formed on the second side (206B) of the first portion (202) to provide air to the first portion (202).

5. The electrochemical device (100) as claimed in claim 4, wherein the first portion (202) comprises a first set of ribs (308) formed on the first side (206A) of the first portion (202) to increase retention time and uniform flow of the fuel flowing thereon and a second set of ribs (310) formed on the second side (206B) of the first portion (202) to increase retention time and uniform flow of the air flowing thereon.

6. The electrochemical device (100) as claimed in claim 5, comprising a top end plate (106A) provided in contact with a top of the stack of cells (102) and a bottom end plate (106B) provided in contact with a bottom of the stack of cells (102), wherein the top and bottom end plates (106A-B) are electrical terminals.

7. The electrochemical device (100) as claimed in claim 6, wherein the top end plate (106A) is provided with the first set of ribs (308) on a side of the top end plate (106A) facing the stack of cells (102) and the bottom end plate (106B) is provided with the second set of ribs (310) on a side of the bottom end plate (106B) facing the stack of cells (102).

8. The electrochemical device (100) as claimed in claim 7, wherein the bottom end plate (106B) is provided with the exhaust opening (212) and the air channel (210) on the side of the bottom end plate (106B).

9. The electrochemical device (100) as claimed in claim 8, comprising a pair of compression plates (108) provided in contact with the top and bottom end plates (106A-B) of the stack of cells (102) to provide a compressive force to the stack of cells (102).

10. The electrochemical device (100) as claimed in claim 9, wherein each of the end plates (106A-B), the compression plates (108), and the quadrilateral shaped portion (204) comprises at least one hole (312) formed juxtaposed to the exhaust opening (212) to receive a connecting member.

11. The electrochemical device (100) as claimed in claim 10, wherein the connecting member is insulated with a Felt paper.

12. The electrochemical device (100) as claimed in claim 1, wherein the first portion (202) is any one of a circular shape and an octagonal shape.

13. The electrochemical device (100) as claimed in claim 12, wherein the quadrilateral shaped portion (204) is any one of a square shape, a rectangle shape, and a parallelogram shape.

14. The electrochemical device (100) as claimed in claim 4, comprising at least one air guiding member (110) provided in contact with sides of the quadrilateral shaped portion (204) of the stack of cells (102), wherein the air guiding member comprises slots (112) fluidically connected to the second channel formed in the cut-out portion (304) of the quadrilateral shaped portion (204). , Description:TECHNICAL FIELD

The present invention generally relates to an electrochemical device, particularly, to an electrochemical device having modular designed bipolar plates to increase insulation between adjacent stacks of cells and to separate airstream and fuel stream.

BACKGROUND

Generally, the electrochemical devices either generate electricity or produce gas, particularly oxygen and hydrogen, depending upon an input to the device. Here, the electrochemical devices can either be a solid oxide fuel cells (SOFC) or a solid oxide electrolyzer cells (SOEC). In case the electrochemical device is operating as the SOFC, the input to the device may be a fuel stream and an air stream. The SOFC may generate electricity by oxidizing the fuel stream and the air stream. In case the electrochemical device is operating as the SOEC, the input to the device may be electricity. Further, the SOEC may generate the air stream and the fuel stream. Here, the fuel stream can be hydrogen and the airstream can be oxygen stream. In both cases, the electrochemical device is provided with bipolar plates and each bipolar plate is provided with an anode side and a cathode side. The bipolar plates may be stacked together to form a stack of cells. In conventional designs, the bipolar plates are in circular shape having the anode side and the cathode side. As the bipolar plates are circular plates, an insulation needs to be provided between the adjacent stack of cells. Further, it is cumbersome to provide thermal insulation in between the adjacent stack of cells. Moreover, as the conventional design of the bipolar plates requires more insulation, it is cumbersome to add a greater number of stacks of cells into the electrochemical devices. As a result, the electrochemical devices cannot be designed for higher power ratings. In case multiple stacks of cells are arranged together, sealing needs to be provided between the stacks of cells that increases cost and weight of the device.

Accordingly, there remains a need for an electrochemical device designed for higher power ratings. Further, there remains another need for a modified design of bipolar plates that enables adding of multiple stacks of cells together in the electrochemical device. Further, there remains another need for a design of bipolar plates that reduces a thermal insulation between adjacent stacks of cells in the electrochemical device.

SUMMARY

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 intended to determine the scope of the invention.

In an embodiment of the present disclosure, an electrochemical device is disclosed. The electrochemical device includes a stack of cells, and a plurality of bipolar plates having a first portion and a quadrilateral portion. Further, at least one bipolar plate is placed between adjacent cells in the stack of cells. The first portion is having a first side and a second side. Further, the first portion includes a fuel opening formed on a center of the first portion and fluidically in contact with the first side of the first portion to provide a fuel to the first side of the first portion, and at least one air channel formed on the second side of the first portion and fluidically in contact with the second side of the first portion to provide air to the second side of the first portion. Further, the quadrilateral shaped portion, formed around the first portion, includes at least one exhaust opening formed around the first portion and fluidically connected to the first side and the second side of the first portion to receive the fuel and air.

To further clarify the advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

Figs. 1A-B illustrate perspective schematic views of an electrochemical device, in accordance with an embodiment of the present invention;

Figs. 2A-B illustrate schematic views of a bipolar plate of the electrochemical device of Fig. 1A depicting a first and second sides of the bipolar plate;

Figs. 3A-B illustrate schematic views of an octagonal shaped bipolar plate of Fig. 1A, in accordance with another embodiment of the present invention;

Figs. 4A-B illustrate schematic views of the bipolar plate depicting a flow of an air stream and a fuel stream when the electrochemical device of Fig. 1A operating as a SOEC;

Figs. 5A-B illustrate schematic views of a top end plate provided on a stack of cells of the electrochemical device of Fig. 1A;

Figs. 6A-B illustrate schematic views of a bottom end plate provided on the stack of cells of the electrochemical device of Fig. 1A;

Figs. 7A-D illustrate schematic views of the multiple stacks of cells depicting the first and second sides of the bipolar plates of Fig. 1A;

Fig. 8A illustrates another schematic view of the electrochemical device provided with an air guiding member of Figs. 1A-B, in accordance with an embodiment of the present invention;

Fig. 8B illustrates another schematic view of the electrochemical device provided with the air guiding member of Figs. 1A-B, in accordance with another embodiment of the present invention; and

Figs. 9A-B illustrate various views of a bottom insulation plate provided with pipes for enabling the air and fuel communication to the stack of cells of Fig. 1A-B.

Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present invention. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

DETAILED DESCRIPTION OF FIGURES

For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skilled in the art to which this invention belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.

The term “some” as used herein is defined as “none, or one, or more than one, or all.” Accordingly, the terms “none,” “one,” “more than one,” “more than one, but not all” or “all” would all fall under the definition of “some.” The term “some embodiments” may refer to no embodiments or to one embodiment or to several embodiments or to all embodiments. Accordingly, the term “some embodiments” is defined as meaning “no embodiment, or one embodiment, or more than one embodiment, or all embodiments.”

The terminology and structure employed herein is for describing, teaching and illuminating some embodiments and their specific features and elements and does not limit, restrict or reduce the spirit and scope of the claims or their equivalents.

More specifically, any terms used herein such as but not limited to “includes,” “comprises,” “has,” “consists,” and grammatical variants thereof do NOT specify an exact limitation or restriction and certainly do NOT exclude the possible addition of one or more features or elements, unless otherwise stated, and furthermore must NOT be taken to exclude the possible removal of one or more of the listed features and elements, unless otherwise stated with the limiting language “MUST comprise” or “NEEDS TO include.”

Whether or not a certain feature or element was limited to being used only once, either way it may still be referred to as “one or more features” or “one or more elements” or “at least one feature” or “at least one element.” Furthermore, the use of the terms “one or more” or “at least one” feature or element do NOT preclude there being none of that feature or element, unless otherwise specified by limiting language such as “there NEEDS to be one or more . . . ” or “one or more element is REQUIRED.”

Unless otherwise defined, all terms, and especially any technical and/or scientific terms, used herein may be taken to have the same meaning as commonly understood by one having an ordinary skill in the art.

Reference is made herein to some “embodiments.” It should be understood that an embodiment is an example of a possible implementation of any features and/or elements presented in the attached claims. Some embodiments have been described for the purpose of illuminating one or more of the potential ways in which the specific features and/or elements of the attached claims fulfil the requirements of uniqueness, utility, and non-obviousness.

Use of the phrases and/or terms such as but not limited to “a first embodiment,” “a further embodiment,” “an alternate embodiment,” “one embodiment,” “an embodiment,” “multiple embodiments,” “some embodiments,” “other embodiments,” “further embodiment”, “furthermore embodiment”, “additional embodiment” or variants thereof do NOT necessarily refer to the same embodiments. Unless otherwise specified, one or more particular features and/or elements described in connection with one or more embodiments may be found in one embodiment, or may be found in more than one embodiment, or may be found in all embodiments, or may be found in no embodiments. Although one or more features and/or elements may be described herein in the context of only a single embodiment, or alternatively in the context of more than one embodiment, or further alternatively in the context of all embodiments, the features and/or elements may instead be provided separately or in any appropriate combination or not at all. Conversely, any feature and/or element described in the context of separate embodiments may alternatively be realized as existing together in the context of a single embodiment.

Any particular and all details set forth herein are used in the context of some embodiments and therefore should NOT be necessarily taken as limiting factors to the attached claims. The attached claims and their legal equivalents can be realized in the context of embodiments other than the ones used as illustrative examples in the description below.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

Figs. 1A and 1B illustrate perspective schematic views of an electrochemical device 100, in accordance with an embodiment of the present invention. Here, the electrochemical device 100 can be a solid oxide fuel cell, hereinafter referred to as SOFC, and a solid oxide electrolyzer cell, hereinafter referred to as SOEC. In one example, the SOFC is an electrochemical conversion device configured to convert a chemical energy into an electrical energy. In other words, the SOFC is configured to produce the electricity directly from oxidizing a fuel provided in the SOFC. Generally, the fuel cells may be characterized by their electrolyte material. In the present example, the SOFC has a solid oxide or ceramic electrolyte. Similarly, the SOEC is a device that converts the electricity into gases. Particularly, the SOEC is a solid oxide fuel cell that runs in a regenerative mode to achieve the electrolysis of water (and/or carbon dioxide) by using a solid oxide, or ceramic electrolyte to produce the hydrogen gas (and/or carbon monoxide) and oxygen gas.

The electrochemical device 100 includes a stack of cells 102 and a plurality of bipolar plates 104. Here, at least one bipolar plate 104 is provided between adjacent cells in the stack of cells 102. In other words, a bipolar plate 104 is sandwiched by two adjacent cells in the stack of cells 102. Further, construction and geometry of the bipolar plate will be explained with respect to the forthcoming figures.

Further, the device 100 includes a top end plate 106A and a bottom end plate 106B. Here, the top end plate 106A is provided in contact with a top of the stack of cells 102 and the bottom end plate 106B is provided in contact with a bottom of the stack of cells 102 as shown in Fig. 1A. In other words, the top end plate 106A and the bottom end plate 106B are sandwiching the stack of cells 102. In this example, the top end plate 106A and the bottom end plate 106B are electrical terminals. Further, a detailed view of the top end plate 106A and the bottom end plate 106B are shown in the forthcoming figures and explained with respect to those figures.

Further, the device 100 includes a pair of compression plates 108 provided in contact with the top end plate 106A and the bottom end plate 106B to provide a compressive force to the stack of cells 102. The compression plates 108 are sandwiching the top end plate 106A and the bottom end plate 106B of the stack of cells 102. Further, a connecting member such a lengthy screw passes through the stack of cells 102, the top and bottom end plates 106A-B and the compression plates 108, so that the compressive strength may be provided to the stack of cells 102. The device 100 further includes at least one air guiding member 110 having slots 112 to provide/receive an air stream to/from the stack of cells 102. Here, the air guiding member 110 may be in contact to the sides of the bipolar plates 104 to provide/receive air to/from the stack of cells 102. Further, construction and placement of the air guiding member 110 are explained later in this document.

Figs. 2A-B illustrate schematic views of a bipolar plate amongst the plurality of bipolar plates 104 of Fig. 1A. Here, the bipolar plate 104 may include a first portion 202 and a quadrilateral shaped portion 204 formed around the first portion 202. The first portion 202 may include a first side 206A and a second side 206B formed on the opposite side to the first side 206A. In other words, the first side 206A of the first portion 202 is opposite to the second side 206B of the first portion 202. In this example, the first side 206A is an anode side of the bipolar plate 104 and the second side 206B is a cathode side of the bipolar plate 104. In another example, the first side 206A may be referred to as a fuel stream side of the bipolar plate 104 and the second side 206B may be referred to as an air stream side of the bipolar plate 104. In this example, Fig. 2A shows a schematic view of the bipolar plate 104 depicting the second side 206B of the first portion 202 and the Fig. 2B shows another schematic view of the bipolar plate 104 depicting the first side 206A of the first portion 202.

As shown in Fig. 2B, the first portion 202 includes a fuel opening 208 formed on a center of the first portion 202 and fluidically in contact with the first side 206A of the first portion 202 to provide the fuel stream to the first side 206A of the first portion 202. In one example, the fuel opening 208 is adapted to provide the fuel stream to the stack of cells 102 when the device 100 operates as the SOFC. In another example, the fuel opening 208 is adapted to receive the fuel stream, particularly hydrogen, from the stack of cells 102 when the device 100 operates as the SOEC. The first portion 202 further includes at least one air channel 210 formed on the second side 206B as shown in Fig. 2A. Here, the air channel 210 is fluidically in contact with the second side 206B of the first portion 202 to provide/receive the air stream to/from the second side 206B of the first portion 202. In one example, the air channel 210 may provide the air stream to the second side 206B of the first portion 202 when the device 100 operates as the SOFC. In another example, the air channel 210 may receive the air stream from the second side 206B of the first portion 202 when the device 100 operates as the SOEC. In such case, the air stream can be hot air fed to the air channel 210. Here, the air channel 210 may form as closed channel when the bipolar plates 104 are stacked together.

In the preferred example, the first portion 202 has multiple air channels 210 formed on the second side 206B of the first portion 202. Here, the air channel 210 may be in fluidic communication with the slots 112 formed in the air guiding member 110. Particularly, the air guiding member 110 is assembled to the stack of cells 104 in such as a way that the slots 112 of the air guiding member 110 can be in fluidic communication with the air channel 210 formed on the second side 206B of the first portion 202.

As explained, the quadrilateral shaped portion 204 is formed around the first portion 202 in such a way that the first portion 202 is juxtaposed to the quadrilateral shaped portion 204. Further, the first portion 202 and the quadrilateral shaped portion 204 are in a same plane. The quadrilateral shaped portion 204 includes at least one exhaust opening 212 formed around the first portion 202 and fluidically connected to the first side 206A and the second side 206B of the first portion 202 to receive/provide the fuel stream and the air stream from/to the exhaust opening 212. In this example, the exhaust opening 212 is formed on a corner of the quadrilateral shaped portion 204. In the preferred example, the quadrilateral shaped portion 204 may include four exhaust openings 212 formed on the four corners of the quadrilateral shaped portion 204. Here, the quadrilateral shaped portion 204 may have a space to receive the first portion 202 and an unoccupied space in the quadrilateral shaped portion 204 by the first portion 202 may be considered as the exhaust openings 212. In one embodiment, the quadrilateral shaped portion 204 may be rectangular shaped portion or square shaped portion, and the first portion 202 may be a circular shaped portion. In another embodiment, the quadrilateral shaped portion 204 may be rectangular shaped portion or square shaped portion, and the first portion 202 may be an octagonal shaped portion. Further, the octagonal shaped first portion 202 is shown in the forthcoming figures. In both embodiments, the quadrilateral shaped portion 204 can be any one of a square shape, a rectangle shape, and a parallelogram shape. As the quadrilateral shaped portion 204 is rectangular or square in shape, and the first portion 202 is circular in shape, some openings are detrimentally formed in the quadrilateral shaped portion 204 when the first portion 202 is received in the quadrilateral shaped portion 204. Such openings can be referred to as the exhaust openings 212 to egress hot air/exhaust gas from the stack of cells 102.

Referring to Fig. 2A, the first portion 202 is provided with a protrusion 302 formed on the circumference of the fuel opening 208. The protrusion 302 is formed on the circumference of the fuel opening 208 in the first portion 202 in such a way that the protrusion 302 protrudes towards the second side 206B of the first portion 202. Here, the protrusion 302 is adapted to fluidically isolate the fuel opening 208 from the second side 206B of the first portion 202. Particularly, the protrusion 302 acts as a barrier to the fuel stream when the bipolar plates 104 are stacked together. In other words, the protrusion 302 may be formed on the second side 206B of the first portion 202 at the circumference of the fuel opening 208 in such a way that the protrusion 302 protrudes and touches the first side 206A of adjacent bipolar plate 104 when the bipolar plates 104 are stacked together. As the protrusion 302 touches the first side 206A of the adjacent bipolar plate 104, the protrusion 302 isolate the second side 206B from the fuel openings 208. Hence, the fuel stream flowing in the fuel openings 208 may not reach second side 206B of the first portion 202 and the air stream flowing the second side 206B of the first portion 202 may not reach the fuel opening 208. Therefore, the air stream and the fuel stream may not directly interact in the bipolar plates 104 but it helps for the oxidizing process.

Referring to Figs. 2A-B, the quadrilateral shaped portion 204 further includes at least one cut-out portion 304 formed on four sides of the quadrilateral shaped portion 204. Here, the cut-out portions 304 can be a semi-circular cut-out portion. Although Figs.2A-B show the cut-out portions 304 as the semi-circular cut-out portions, it is possible to shape the cut-out portions 304 into different shapes such as semi-square or semi-rectangle. The cut-out portions 304 acts as insulators between two adjacent stack of cells 102. It will be shown in the forthcoming figure. Further, the cut-out portions 304 may include at least one second channel 306 formed on a side of the cut-out portion 304 that is in line to the second side 206B of the first portion 202. Therefore, the second channel 306 can be in-line to the air channel 210 formed on the second side 206B of the first portion 202 to provide/receive the air stream to/from the first portion 202.

Further, the first portion 202 includes a first set of ribs 308 as shown in Fig. 2B. The first set of ribs 308 is formed on the first side 206A of the first portion 202 of the bipolar plate 104 to increase retention time and uniform flow of the fuel stream flowing thereon. In case the device 100 is operating as the SOFC, the fuel stream may flow from the fuel opening 208 to the first side 206A of the first portion 202 having the first set of ribs 308. In case the device 100 is operating as the SOEC, the fuel stream may flow from the first side 206A of the first portion 202 to the fuel opening 208. In both cases, the first set of ribs 308 increases the retention time of the fuel stream in the first side 206A of the first portion 202 to enable optimum energy conversion, i.e., either the electrical energy to the chemical energy or the chemical energy to the electrical energy.

Similarly, the second side 206B of the first portion 102 is provided with a second set of ribs 310 as shown in Fig. 2A. Here, the second set of ribs 310 is formed on the second side 206B to increase retention time and uniform flow of the air stream flowing thereon. The second set of ribs 310 may provide turbulence to the air stream flowing thereon so that the air may be in contact with the second side 206B of the first portion 202 for a longer time, thereby achieving optimum energy conversion. In Figs. 2A-B, the direction of the air flow and the fuel flow is toward the exhaust opening 212, which means the device 100 is operating as the SOFC. In case the device 100 operating as the SOEC, the direction of the fuel stream and the air stream flow will be towards the fuel opening 208 and the air channel 210 of the bipolar plate 104 respectively.

Figs. 3A-B illustrate schematic views of the bipolar plate 104 of Fig. 1A, in accordance with an embodiment of the present invention. In this embodiment, the first portion 202 of the bipolar plate 104 is shaped in an octagonal shape. As explained in Fig. 2A-C, the previous embodiment, the bipolar plate 104 is having the first portion 202 and the quadrilateral shaped portion 204 formed around the first portion 202. In this embodiment, the bipolar plate 104 has all the limitation and designs of the bipolar plate 104 of the previous embodiment. For the sake of brevity, features of the present disclosure that are already described in detail in the description of Figs. 2A-B are not described in detail in the description of Figs. 3A-B. In this embodiment, the shape of the first portion 202 is different from the shape of the first portion 202 of the previous embodiment as shown in Figs. 2A-B. Fig. 3A shows the second side 206B of the first portion 202 of the bipolar plate 104 and Fig. 3B shows the first side 206A of the first portion 202 of the bipolar plate 104. Here, the first portion 202 is of the octagonal shape. Further, a side of the octagonal shaped first portion 202 may be in contact with the cut-out portion 304 formed on the quadrilateral shaped portion 204. Hence, four sides of the octagonal shaped first portion 202 are in contact with the cut-out portions 304 of the quadrilateral shaped portion 204 and other four sides of the octagonal shaped first portion 202 are defining edges for the exhaust openings 212.

Figs. 4A-B illustrate schematic views of the bipolar plate 104 of Fig. 1A depicting a flow of the air and fuel streams when the device operating as the SOEC. According to the Figs. 4A-B, constructional features, and geometry of the bipolar plate 104 are same as described in the description of Figs. 2A-B. For the sake of brevity, such constructional features and geometry are not described with respect to Figs. 4A-B in the present disclosure. In this embodiment, the device 100 may operate as the SOEC and generates the fuel and air streams, particularly, generates the hydrogen and oxygen streams. As the device 100 operates as the SOEC in this embodiment, the input can be electricity provided to the top and bottom end plates 106A-B. Due to electrolysis process in the device, the oxygen and hydrogen streams are generated in the stack of cells 102.

As shown in Fig. 4A, the oxygen stream flows from the exhaust opening 212 to the second side 206B of the first portion 202. Thereafter, the oxygen stream enters the air channel 210 formed on the second side 206B of the first portion 202. Further, the oxygen stream egresses from the bipolar plates 104 through the second channel 306 formed on the quadrilateral shaped portion 204. As the air guiding member 110 is connected to the quadrilateral shaped portion 204, the oxygen stream may egress from the device 100 through the slots 112 formed in the air guiding member 110. Similarly, the fuel stream, i.e., hydrogen stream may flow from the exhaust opening 212 to the first side 206A of the first portion 202 as shown in Fig. 4B. Thereafter, the hydrogen stream flows to the fuel opening 208 formed in the first portion 202. Further, the hydrogen stream can be egressed from the stack of cells 102 through pipes connected to the bottom side of the stack of cells 102.

Figs. 5A-B illustrate schematic views of the top end plate 106A provided on the stack of cells 102 of the device 100 of Fig. 1A. Particularly, Fig. 5A shows a first side 502 of the top end plate 106A and Fig. 5B shows a second side 504 of the top end plate 106A. Here, the first side 502 of the top end plate 106A is facing the stack of cells 102 upon assembling the top end plate 106A on the stack of cells 102. Further, the top end plate 106A is provided with the first set of ribs 308 on a side of the top end plate 106A facing the stack of cells 102. In other words, the first set of ribs 308 is provided on the first side 502 of the top end plate 106A. Further, the second side 504 of the top end plate 106A is in contact with the compression plate 108 when the compression plate 108 is assembled on the stack of cells 102. Here, the fuel opening 208 and the exhaust opening 212 are closed so as to restrict egressing of the fuel and air from the top side of the stack of cells 102.

Figs. 6A-B illustrate schematic views of the bottom end plate 106B provided on the stack of cells 102 of the device 100 of Fig. 1A. Particularly, Fig. 6A shows a first side 602 of the bottom end plate 106B and Fig. 6B shows a second side 604 of the bottom end plate 106B. Here, the first side 602 of the bottom end plate 106B is facing the stack of cells 102 upon assembling the bottom end plate 106B at the bottom of the stack of cells 102. Further, the bottom end plate 106B is provided with the second set of ribs 310 on a side of the bottom end plate 106B facing the stack of cells 102. In other words, the second set of ribs 310 is provided on the first side 602 of the bottom end plate 106B. Further, the second side 604 of the bottom end plate 106B is in contact with the compression plate 108 when the compression plate 108 is assembled on the stack of cells 102. As shown in Fig. 6A, the bottom end plate 106B is provided with the air channel 210 on the first side 602 of the bottom end plate 106B. In addition, the bottom end plate 106B is provided with the exhaust openings 212 on the first side 602 of the bottom end plate 106B so that the exhaust gas egresses from the bottom side of the stack of cells 102.

Referring to Figs. 1A-B, 2A-B, 5A-B and 6A-B, each of the top and bottom end plates 106A-B, the compression plates 108, and the quadrilateral shaped portion 204 comprise at least one hole 312 formed juxtaposed to the exhaust opening 212 to receive a connecting member. As explained above, the connecting member can be nut and bolt assembly adapted to provide compressive strength to the stack of cells 102. Further connecting member is insulated with a FELT paper.

Figs. 7A-D illustrate schematic views of the multiple stacks of cells 102 depicting the first and second sides 206A-B of the bipolar plates 104 of Fig. 1A. In this example, Fig. 7A shows 2x3 stack of cells 102 depicting the second side 206B of the bipolar plates 104, and Fig. 7B shows 3x3 stack of cells 102 depicting the second side 206B of the bipolar plates 104. Here, the second side 206B of the bipolar plates 104 means the air stream side. In Fig. 7A, six stacks of cells 102 are shown and each stack of cells is placed adjacent to each other. Consider two stacks from the six stacks of cells 102, for example, a first stack 102A and a second stack 102B. Here, the first stack 102A is placed adjacent to the second stack 102B. Further, the second stack 102B is placed next to the first stack 102A in such a way the cut-out portion 304 of the bipolar plate 104 of the first stack 102A contacts with the cut-out portion 304 of the bipolar plate 104 of the second stack 102B. Further, the cut-out portion 304 of the first stack 102A and the cut-out portion 304 of the second stack 102B may form an elliptical opening 702 between the first stack 102A and the second stack 102B. The elliptical opening 702 is configured to provide/receive the air stream to the bipolar plates 104 of the all the stack of cells 102. Particularly, the elliptical opening 702 is adapted to provide/receive the air stream to/from the air channel 210 formed on the first side 206A of the bipolar plate 104. Further, the elliptical opening 702 and the fuel opening 208 may be in fluidic communication with inlet/outlet pipes formed in the compression plate 108 formed at the bottom of the device 100. Figs. 7C-D illustrate schematic views of the multiple stacks of cells 102 depicting the first side 206A of the bipolar plates. In this example, Fig. 7C shows 2x3 stack of cells 102 depicting the first side 206A of the bipolar plates 104, and Fig. 7C shows 3x3 stack of cells 102 depicting the first side 206A of the bipolar plates 104. Here, the fuel openings 208 may be fluidically connected to the fuel inlet/outlet pipes formed in the compression plate 108 formed at the bottom of the device 100. Similarly, the exhaust openings 212 may be fluidically connected to the exhaust pipe formed in compression plate 108 connected at the bottom of the device 100. Above mentioned features are explained with respect to forthcoming figures.

Fig. 8A illustrates another schematic view of the device 100 provided with the air guiding member 110 of Figs. 1A-B, in accordance with an embodiment of the present invention. In this embodiment, the air guiding member 110 is provided with the slots 112 corresponding to each air channel 210 formed in the bipolar plate 104 of the device 100. Here, the air guiding member 110 has individual slots 112 for each air channel 210 formed in the bipolar plate 104. Fig. 8B illustrates another schematic view of the device 100 provided with the air guiding member 110 of Figs. 1A-B, in accordance with another embodiment of the present invention. In this embodiment, the slots 112 of the air guiding member 110 are provided as grouped openings as shown in Fig. 8B. Here, a group of the air channels 210 of the bipolar plates 104 may receive the air stream from a slot formed in the air guiding member 110. In both embodiments, the air guiding member 110 is ceramic insulator.

Figs. 9A-B illustrate various views of a bottom insulation plate 900 provided with the pipes for enabling the air and fuel communication to the stack of cells 102 of Fig. 1A-B. The bottom insulation plate 900 may receive the multiple stacks of cells 102. Particularly, Fig. 9A shows a schematic view the bottom insulation plate 900 depicting air stream pipes 902, fuel stream pipes 904 and an exhaust stream pipe 906, and Fig. 9B shows a cross-sectional view of the bottom insulation plate 900 depicting a connection between the air stream pipe and the elliptical opening 702 and another connection between the exhaust pipe 906 and the exhaust openings 212.

As explained above, the elliptical openings 702 formed between two adjacent stack of cells 102 are fluidically connected to the air stream pipe 902 and the exhaust openings 212 in each stack of cells 102 are fluidically connected to the exhaust pipe 906. Here, the air stream pipe 902 may provide the air stream to the stack of cells 102 if the device 100 is operating as the SOFC. In case the device 100 is operating as the SOEC, the air stream pipe 902 may receive the air stream from the stack of cells 102. Similarly, the fuel stream pipe 904 may provide the fuel stream to the stack of cells 102 if the device 100 is operating as the SOFC. In case the device 100 is operating as the SOEC, the fuel stream pipe 902 may receive the fuel stream from the stack of cells 102.

As explained above, the present design of the bipolar plates 104 does not require any insulator as the cut-out portions 304 act as the insulator. Hence, it is easy to add multiple stacks of cells 102 together, thereby increasing power rating of the device 100. As there is no thermal insulation between adjacent stack of cells, weight and cost of the device 100 can also be significantly reduced.

The figures and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, orders of processes described herein may be changed and are not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts necessarily need to be performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples. Numerous variations, whether explicitly given in the specification or not, such as differences in structure, dimension, and use of material, are possible.