Description:AN IMMERSION-COOLED PRISMATIC MODULAR BATTERY SYSTEM

FIELD OF THE DISCLOSURE
[0001] This invention generally relates to a field of prismatic battery systems, and more specifically relates to an immersion-cooled prismatic modular battery system configured to modulate temperature of prismatic cells, in order to facilitate proper functioning of the prismatic cells.

BACKGROUND
[0002] The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also correspond to implementations of the claimed technology.
[0003] A battery cell has been proposed in the past as a clean, efficient, and environmentally responsible power source for electric vehicles and various other applications. One type of battery cell is known as a lithium-ion battery. The lithium-ion battery is rechargeable and can be formed into a wide variety of shapes and sizes to fill available space in the electric vehicles efficiently. For example, the battery cell may be prismatic in shape to facilitate stacking of the battery cells. A plurality of individual battery cells may be provided in a battery pack to provide an amount of power sufficient to operate the electric vehicles. However, a major drawback of the battery cell architectures using the lithium battery cells is that the lithium battery cells generate heat during operation. Additionally, as a result of recharging the lithium battery cells, the lithium battery cells are overheated or otherwise exposed to high-temperature environments, due to which undesirable effects may impact the operation of the lithium-ion batteries.
[0004] There have been many prismatic battery cell systems developed in the recent past to mitigate the effect of heat produced due to charging or discharging of the battery cells. One of the developed prismatic battery cell system in recent past is a traditional prismatic battery cell system in which a lithium plating is used in anodes of the traditional prismatic battery cell system. The traditional prismatic battery system is configured to maintain uniform surface temperatures over the lithium battery cells used as the prismatic cells, and efficiently transfers the heat away from the lithium battery cells. This enables higher charging or discharging rates with significantly improved battery life. However, a major drawback of the prismatic battery cell systems is that in the traditional prismatic battery cell systems or currently developed prismatic battery cell systems, low temperatures affect performance of the lithium-ion cells, due to which degradation in the performance of the prismatic battery is caused by reduction of ionic conductivity and increase of charge-transfer resistance of the lithium-ion cells. Furthermore, the lithium plating leads to loss of capacity at the low temperatures and reduction in the life and capacity of the lithium battery pack. Furthermore, the lithium-ion cells undergo bloating or swelling after prolonged charging and discharging cycles, thereby resulting in additional forces on the lithium-ion cells and the battery casing which if left unmitigated, drastically reduces life of the lithium-ion cells. Increased forces in the battery due to the swelling could lead to short-circuit of the lithium-ion cells and is a safety hazard. Additionally, the traditional prismatic battery cells systems or the currently developed prismatic battery cell systems fails to achieve modulation of the temperature of the lithium-ion cells required for proper functioning of the battery and its health preservation. Moreover, the design of currently developed prismatic battery cell systems involves use of battery cell modules in which the cells are closed in the battery, and require structural parts to pack the prismatic cells together, thereby leading to increase in battery weight and parts.
[0005] Hence, considering the above mentioned drawbacks in the currently developed prismatic battery cell systems, there is an urgent need for a prismatic modular battery cell system which not only reduces additional forces on the prismatic cells and the battery casing and swelling of the prismatic cells, but also solves the aforementioned drawbacks, by being able to modulate the temperature of the lithium-ion cells, in order to ensure proper functioning of the battery and its health preservation, as well as prevents use of battery cell modules and the structural parts, thereby resulting in effective packing of the prismatic cells in order to prevent the prismatic cells from getting damaged and facilitate decrease in the battery weight and parts and reduce the number of assembly steps.

OBJECTIVES OF THE INVENTION
[0006] It is an objective of the invention to provide an immersion-cooled prismatic modular battery system configured to modulate temperature of prismatic cells, in order to facilitate proper functioning of the prismatic cells.
[0007] It is an objective of the invention to provide the immersion-cooled prismatic modular battery system having a prismatic battery pack that is temperature controlled using circulation of fluid throughout inside of a battery compartment consisting of prismatic cells.
[0008] It is an objective of the invention to provide the immersion-cooled prismatic modular battery system having prismatic cells which produce heat while charging or discharging, and dissipate the heat to the circulating fluid.
[0009] It is an objective of the invention to provide the immersion-cooled prismatic modular battery system in which a temperature control fluid (TCF) is configured to move around surface of the prismatic cells through a pump, and thermal energy collected from the prismatic cells by the TCF is passed to a chiller unit.
[0010] It is an objective of the present invention to provide the immersion-cooled prismatic modular battery system in which a battery casing is provided which is configured to allow the TCF to absorb heat from the prismatic cells before the heat leaves the battery casing.
[0011] It is an objective of the present invention to provide the immersion-cooled prismatic modular battery system which comprises of a compressible foam configured to put together the prismatic cells, to accommodate bloating of the prismatic cells.
[0012] It is an objective of the invention to provide the immersion-cooled prismatic modular battery system in which the prismatic cells are stacked using a fixture to ensure desired parameters of cell stacking, and a stacked pile is compressed using a portion of the fixture.
[0013] It is an objective of the invention to provide the immersion-cooled prismatic modular battery system in which the prismatic cells of the prismatic battery pack are flexibly packed together through a high-strength band, to maintain compression force, upon removal of the compression fixture.
[0014] It is an objective of the invention to provide the immersion-cooled prismatic modular battery system in which the battery casing is configured to be reusable once the prismatic cells get enough degraded and require replacement.
[0015] It is an objective of the invention to provide the immersion-cooled prismatic modular battery system in which the compressible foam is provided to maintain a uniform level of compressive load on the prismatic cells through the battery casing.
[0016] It is an objective of the invention to provide the immersion-cooled prismatic modular battery system in which the battery casing comprises of flow channels that facilitate flow of the TCF in a controlled direction to attain temperature control of each of the prismatic cells.
[0017] It is an objective of the invention to provide the immersion-cooled prismatic modular battery system which is cost-effective, requires less efforts, reusable, and recyclable, and helps in building a greener and sustainable future.
[0018] It is an objective of the invention to provide the immersion-cooled prismatic modular battery system in which the prismatic cells are configured to be immersed in a dielectric coolant, which enables efficient and rapid transfer of heat from the prismatic cells to the dielectric coolant by reducing the thermal resistance in the heat transfer.
[0019] It is an objective of the invention to provide the immersion-cooled prismatic modular battery system in which the rapid transfer of the heat leads to an increase in the safety of the battery, and in case of a thermal runaway event, the heat is quickly taken away from the cell of the battery which has heated and failed, which ensures that the heat from the failed cell does not remain concentrated, thereby protecting other nearby cells from thermal propagation.

SUMMARY
[0020] In accordance with some embodiments of present inventive concepts, an immersion-cooled prismatic modular battery system is claimed, which is configured to modulate temperature of prismatic cells, in order to facilitate proper functioning of the prismatic cells. The immersion-cooled prismatic modular battery system mainly comprises of a battery compartment having different mechanical components. These mechanical components are a battery casing, a plurality of prismatic cells, and a compressible foam. The battery casing comprises a top casing plate, a plurality of casing side walls, and a plurality of flow channels. The plurality of flow channels is configured to allow flow of temperature control fluid (TCF) in a controlled direction. The plurality of prismatic cells is configured to be positioned on the battery casing and tightly coupled with the battery casing, and at least one prismatic cell is configured to be attached to a cell pull-out band. The compressible foam is configured to accommodate the plurality of prismatic cells and maintain a uniform level of compressive load on the plurality of prismatic cells, through the battery casing. The TCF is configured to move around surface of each of the plurality of prismatic cells through a pump, and collect thermal energy from each of the plurality of prismatic cells. The battery casing is configured to allow the TCF to absorb heat from each of the plurality of prismatic cells before the TCF leaves the battery casing and entering a chiller unit. The chiller unit is configured to exchange heat between the TCF and a refrigerant, and the heat is configured to be released in environment through a radiator unit.
[0021] In an embodiment, a charging socket and a discharging port is provided on at least one casing side wall of the plurality of casing side walls, to provide charging and discharging of the plurality of prismatic cells.
[0022] In another embodiment, an air-bleed vent is provided which is configured to be positioned on a surface of the top casing plate, to allow for bleeding of trapped air when coolant is being filled for the first time. It is not operated during regular use. A plurality of fastener bolts are positioned on the top casing plate and configured to fasten the at least one casing side wall with the top casing plate.
[0023] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The accompanying drawings illustrate various embodiments of systems, methods, and embodiments of various other aspects of the disclosure. Any person with ordinary skills in the art will appreciate that the illustrated element boundaries (e.g., boxes, groups of boxes, or other shapes) in the figures represent one example of the boundaries. It may be that in some examples one element may be designed as multiple elements or that multiple elements may be designed as one element. In some examples, an element shown as an internal component of one element may be implemented as an external component in another, and vice versa. Furthermore, elements may not be drawn to scale. Non-limiting and non-exhaustive descriptions are described with reference to the following drawings. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating principles.
[0025] FIG. 1A illustrates a first perspective view of an immersion-cooled prismatic modular battery system, according to embodiments disclosed herein;
[0026] FIG. 1B illustrates a cross-sectional view of the immersion-cooled prismatic modular battery system, according to the embodiments disclosed herein;
[0027] FIG. 1C illustrates a third perspective view of the immersion-cooled prismatic modular battery system, according to the embodiments disclosed herein;
[0028] FIG. 1D illustrates a block diagram illustrating a refrigeration cycle having different functional units of the actively-cooled prismatic modular battery system, according to the embodiments disclosed herein;
[0029] FIG. 2 illustrates a left-side view of the immersion-cooled prismatic modular battery system, according to the embodiments disclosed herein;
[0030] FIG. 3 illustrates a top view of the immersion-cooled prismatic modular battery system, according to the embodiments disclosed herein;
[0031] FIG. 4 illustrates an inner view of the immersion-cooled prismatic modular battery system with an open top casing plate, according to the embodiments disclosed herein;
[0032] FIG. 5 illustrates another inner view of the immersion-cooled prismatic modular battery system with the open top casing plate, according to the embodiments disclosed herein;
[0033] FIG. 6 illustrates yet another inner view of an immersion-cooled prismatic modular battery system with the open top casing plate, according to the embodiments disclosed herein;
[0034] FIG. 7A illustrates an isometric view of an immersion-cooled prismatic modular battery system with the open top casing plate and the prismatic cells removed, according to the embodiments disclosed herein;
[0035] FIG. 7B illustrates another isometric view of an immersion-cooled prismatic modular battery system with the open top casing plate and the prismatic cells removed, according to the embodiments disclosed herein;
[0036] FIG. 8 illustrates a side view of the immersion-cooled prismatic modular battery system, according to the embodiments disclosed herein;
[0037] FIG. 9 illustrates a sectional view of the immersion-cooled prismatic modular battery system, according to the embodiments disclosed herein;
[0038] FIG. 10 illustrates an isometric view of a stacked configuration of compressed cells after removing a compression fixture, according to the embodiments disclosed herein;
[0039] FIG. 11 illustrates another sectional view of the immersion-cooled prismatic modular battery system, according to the embodiments disclosed herein; and
[0040] FIG. 12 illustrates another cross-sectional view of the immersion cooled prismatic modular battery system, according to the embodiments disclosed herein.

DETAILED DESCRIPTION
[0041] Some embodiments of the disclosure, illustrating all its features, will now be discussed in detail. The words “comprising,” “having,” “containing,” and “including,” and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items. It must also be noted that as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. Although any systems and methods similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, the preferred, systems and methods are now described. Embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings in which like numerals represent like elements throughout the several figures, and in which example embodiments are shown. Embodiments of the claims may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. The examples set forth herein are non-limiting examples and are merely examples among other possible examples.
[0042] While the present invention is described herein by way of example using embodiments, those skilled in the art will recognize that the invention is not limited to the embodiments described, and are not intended to represent the scale of the various components. It should be understood that the detailed description thereto is not intended to limit the invention to the particular form disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the scope of the present invention as defined by the appended claim. As used throughout this description, the word “may” is used in a permissive sense (i.e. meaning having the potential to), rather than the mandatory sense, (i.e. meaning must). Further, the words “a” or “an” mean “at least one” and the word “plurality” means “one or more” unless otherwise mentioned. Furthermore, the terminology and phraseology used herein is solely used for descriptive purposes and should not be construed as limiting in scope. Language such as “including,” “comprising,” “having,” “containing,” or “involving,” and variations thereof, is intended to be broad and encompass the subject matter listed thereafter, equivalents, and additional subject matter not recited, and is not intended to exclude other additives, components, integers, or steps. Likewise, the term “comprising” is considered synonymous with the terms “including” or “containing” for applicable legal purposes. Any discussion of documents, acts, materials, devices, articles, and the like is included in the specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention.
[0043] The present invention is described hereinafter by various embodiments. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiment set forth herein. Rather, the embodiment is provided so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those skilled in the art. In the following detailed description, numeric values and ranges are provided for various aspects of the implementations described. These values and ranges are to be treated as examples only, and are not intended to limit the scope of the claims. In addition, a number of materials are identified as suitable for various facets of the implementations. These materials are to be treated as exemplary, and are not intended to limit the scope of the invention.
[0044] The present invention discloses an immersion-cooled prismatic modular battery system which is configured to modulate temperature of prismatic cells, in order to facilitate proper functioning of the prismatic cells. The immersion-cooled prismatic modular battery system comprises of a prismatic battery pack that is temperature controlled using circulation of a fluid throughout inside of a battery compartment and around surface of prismatic cells inside the battery compartment. In effect, the prismatic cells that produce heat while charging or discharging, dissipate the heat to the circulating fluid. The circulated fluid is temperature control fluid (TCF) configured to be moved around the prismatic cells through a pump and thermal energy is collected from each of the prismatic cells by the temperature control fluid. The collected thermal energy is passed to a chiller unit.
[0045] Referring to FIG. 1A illustrating a first perspective view of an immersion-cooled prismatic modular battery system (100), according to embodiments disclosed herein, the immersion-cooled prismatic modular battery system (100) mainly comprises a battery compartment (102) housing a plurality of mechanical components. The plurality of mechanical components housed within the battery compartment are a battery casing (104), a plurality of prismatic cells (shown in FIG. 1B), and a compressible foam (shown in FIG. 1B). The battery casing (104) is configured to house the plurality of prismatic cells. The battery casing (104) is further configured to be designed in a manner such that, the battery casing (104) allows a temperature control fluid (TCF) to absorb heat from each of the plurality of prismatic cells before leaving the battery casing (104). The battery casing (104) is further configured to be reusable if the plurality of prismatic cells get enough degraded and require replacement. The battery casing (104) has a bottom portion composed of a fire-resistant material to form a plurality of flow channels (shown in FIG. 6) for the TCF to flow through the prismatic battery pack. The battery casing (104) further comprises a top casing plate (106), a plurality of casing side walls (108), and the plurality of flow channels.
[0046] In one embodiment, dimensions of the battery casing (104) are designed in a manner such that the plurality of prismatic cells experience a constant compression force.
[0047] In another embodiment, the battery casing (104) is made of a material selected from a group of materials of aluminium material, plastic material, steel material, composite material or any other metallic material.
[0048] The top casing plate (106) is the topmost portion of the battery compartment (102) and configured to be designed of varied lengths. The top casing plate (106) is bolted to the battery casing (104) after the internal components have been assembled inside the battery casing (104). The top casing plate (106) is further configured to be prepared through a laser cutting process, or a stamping process, or a casting process to ensure flexible size of the battery casing (104).
[0049] In an embodiment, the top casing plate (106) is made of a material selected from a group of materials of aluminium material, plastic material, steel material, or any other metallic material.
[0050] The plurality of casing side walls (108) is configured to allow compression of the plurality of prismatic cells. The plurality of casing side walls (108) comprises of six casing side walls, which are welded to form a closed loop. A top surface of at least one casing side wall is configured to mount a sealing gasket (shown in FIG. 1B), for sealing mating surfaces between the top casing plate (106) and respective side plates. The at least one casing side wall of the plurality of casing side walls (108) is further configured to be fastened with the top casing plate (106), through a plurality of fasteners (124).
[0051] In an embodiment, the plurality of casing side walls (108) is made of aluminium, steel, plastic composites or any other structural material.
[0052] The plurality of casing side walls (108) have a layer of Nomex or FR4-154 or any other electrically insulating material on the inside, to insulate each of the plurality of casing side walls (108) from the battery casing (104).
[0053] The immersion-cooled prismatic modular battery system (100) further comprises a charging socket (118) configured to be positioned on at least one casing side wall of the plurality of casing side walls (108). The charging socket (118) is further configured to provide charging of the plurality of prismatic cells.
[0054] The immersion-cooled prismatic modular battery system (100) further comprises a discharging port (120) configured to be positioned on the at least one casing side wall of the plurality of casing side walls (108). The discharging port (120) is further configured to provide discharging of the plurality of prismatic cells.
[0055] The immersion-cooled prismatic modular battery system (100) further comprises an air-bleed vent (122) configured to be positioned on a surface of the top casing plate (106), to allow for bleeding air from the battery when filling it with coolant. The air-bleed vent (122) is configured to seal when fully tightened. The air-bleed vent is the vent which is cut out to make a hole through which a passage is formed for the air to exit when not tightened.
[0056] The immersion-cooled prismatic modular battery system (100) further comprises a fluid inlet (126) and a fluid outlet (136) configured to be positioned on the at least one casing side wall to provide passage for the TCF to flow out of the battery compartment (102).
[0057] In an embodiment, the fluid inlet (126) and fluid outlet (136) may be made of a material selected from a group of materials of Aluminium, Brass, Steel, Plastics, Composite Fire Resistant material, or any other material.
[0058] In one embodiment, the TCF is configured to move around surface of each of the plurality of prismatic cells through a pump (shown in FIG. 1D), and collect thermal energy from each of the plurality of prismatic cells.
[0059] In another embodiment, the battery casing (102) is configured to allow the TCF to absorb heat from each of the plurality of prismatic cells, before the TCF leaves the battery casing (102).
[0060] FIG. 1B illustrates a cross-sectional view of an immersion-cooled prismatic modular battery system (100B), according to the embodiments disclosed herein. The immersion-cooled prismatic modular battery system (100B) comprises of the top casing plate (106), a plurality of flow channels (110), a plurality of prismatic cells (112), a compressible foam (116), an insulation sheet (154), an expandable foam (160), a sealing gasket (162), and other casing side walls (168). The plurality of flow channels (110) is configured to allow flow of the temperature control fluid (TCF) in as controlled direction. The plurality of flow channels (110) is further configured to facilitate cooling of the plurality of prismatic cells (112), due to the flow of the TCF in the controlled direction. The plurality of prismatic cells (112) is configured to be positioned on the battery casing (104). The plurality of prismatic cells (112) is further configured to be tightly coupled with the battery casing (104). The plurality of prismatic cells (112) is further configured to be packed, pre-compressed using the arrangement shown in Fig 1C, and then installed in the battery casing (104). The plurality of prismatic cells (112) is further configured to dissipate the heat to the circulating fluid or the TCF, while production of heat by each of the plurality of prismatic cells (112) during charging and discharging of the plurality of the prismatic cells (112). The plurality of prismatic cells (112) is further configured to collect thermal energy, during the charging or the discharging of the plurality of prismatic cells (112). The plurality of prismatic cells (112) is further configured to be snugly fitted with the battery casing (104), due to which the plurality of prismatic cells (112) experience an interference fit.
[0061] In one embodiment, the plurality of prismatic cells (112) is further configured to be cooled from three directions, due to the flow of the TCF around the surface of each of the plurality of prismatic cells (112).
[0062] In another embodiment, the plurality of prismatic cells (112) is further configured to be immersion-cooled through the TCF flowing through the plurality of flow channels (110) inbuilt in the battery casing (104).
[0063] In yet another embodiment, each of the plurality of prismatic cells (112) are configured to be interconnected without any separate structural cross members along latitude directions and longitude directions.
[0064] In yet another embodiment, the plurality of prismatic cells (112) is further configured to be packed within the prismatic battery pack while occupying minimum space.
[0065] In yet another embodiment, the plurality of prismatic cells (112) is further configured to function at a particular range of temperature for optimum and healthy performance of the plurality of prismatic cells (112). For this purpose, the temperature of cells needs to be heated up when the cells are cooler than the required temperature range or cooled down when it exceeds the required temperature range.
[0066] In yet another embodiment, one prismatic cell of the plurality of prismatic cells (112) is configured to be attached to a cell pull-out band (shown in FIG. 1C).
[0067] The compressible foam (116) is configured to accommodate the plurality of prismatic cells (112). The compressible foam (116) is further configured to maintain a uniform level of compressive load on the plurality of prismatic cells (112), through the battery casing (104). The compressible foam (116) is further configured to accommodate room for swelling of the prismatic cells. The compressible foam (116) is further configured to pack the plurality of prismatic cells (112) together, in form of a flexible and tightened arrangement.
[0068] In an embodiment, the compressible foam (116) is configured to accommodate bloating of the plurality of prismatic cells (112), while the cells (112) are stacked with a compression fixture (shown in FIG. 1C) to ensure desired parameters of cell stacking and the stacked pile is compressed.
[0069] In one embodiment, the parameters of the compressible foam (116) depends on the specification of each of the plurality of prismatic cells (112). The compressible foam (116) is further configured to maintain a uniform level of compressive load on the plurality of prismatic cells (112), through the battery casing (104).
[0070] The insulation sheet (154) is configured to be positioned adjacent to the cell pull-out band to provide electrical insulation and thermal insulation to the plurality of prismatic cells (112). The expandable foam (160) is configured to be positioned below the top casing plate (106) to stop the flow of the TCF to the top surface of the battery casing (104). The expandable foam (160) is further configured to stop the flow of TCF to top surface of the battery casing (104), where there is little effectiveness in thermal control additionally cutting down pressure loss due to function of the pump.
[0071] The sealing gasket (162) is configured to be mounted on the at least one casing side wall to seal mating surfaces between the top casing plate (106) and the respective side plates.
[0072] FIG. 1C illustrates a third perspective view of an immersion-cooled prismatic modular battery system (100C), according to the embodiments disclosed herein. The immersion-cooled prismatic modular battery system (100C) comprises of the plurality of prismatic cells (112), the cell-pull out band (114), the compressible foam (116), a plurality of compression bands (152), the insulation sheet (154), a compression fixture (156), and a plurality of compression bolts (158). The cell-pull out band (114) is configured to be positioned adjacent to the insulation sheet (154). The cell-pull out band (114) is further configured to be directly attached to at least one prismatic cell of the plurality of prismatic cells (112). The plurality of compression bands (152) is configured to be positioned adjacent to the insulation sheet (154) to compress the plurality of prismatic cells (112) in a stacked configuration. The compression fixture (156) configured to be directly coupled with the plurality of prismatic cells (112), to compress the plurality of prismatic cells (112) in a form of stacked pile and the stacked pile is compressed through a portion of the compression fixture (156).
[0073] In one embodiment, the plurality of compression bolts (158) is configured to couple one end of the compression fixture (156) with one end of another compression fixture (shown in FIG. 4).
[0074] In another embodiment, the compression fixture (156) may be made of a material selected from a group of materials of aluminium material, plastic material, steel material, or any other metallic material.
[0075] In yet another embodiment, the compression fixture (156) is just one way of achieving the required compression, but any other fixture can also be used to achieve a similar result of cell stack compression and banding.
[0076] FIG. 1D illustrates a block diagram illustrating a refrigeration cycle (100D) having different functional units of the immersion-cooled prismatic modular battery system (100) of FIG. 1, according to the embodiments disclosed herein. The different functional units are a battery unit (125), a compressor unit (128), a radiator unit (130), a chiller unit (132), a pump (134), and a heater unit (164). The battery unit (125) is configured to be connected to the pump (134) and the heater unit (164). The compressor unit (128) is configured to be connected with the radiator unit (130) and cool the TCF flowing through the plurality of prismatic cells (112), to cool the plurality of prismatic cells (112). The radiator unit (130) is configured to receive the heat produced due to charging or discharging of the plurality of prismatic cells (112). The radiator unit (130) is further configured to release the produced heat into the environment. The chiller unit (132) is configured to be connected to the compressor unit (128), the radiator unit (130), the pump (134), and the heater unit (164). The chiller unit (132) is further configured to receive the TCF after the TCF absorbs heat produced due to the plurality of the prismatic cells (112). The heater unit (164) is configured to be connected to the battery unit (125) and the chiller unit (132). The heater unit (164) is further configured to be connected to the chiller unit (132) and heat the TCF.
[0077] FIG. 2 illustrates a left-side view of the immersion-cooled prismatic modular battery system (100), according to the embodiments disclosed herein. The immersion-cooled prismatic modular battery system (100) comprises of the top casing plate (106), the plurality of casing side walls (108), the charging socket (118), the discharging port (120), a fluid inlet (126), the fluid outlet (136), a bottom casing plate (138), and a signal connector (140). The fluid inlet (126) is configured to be positioned on an another casing side wall of the plurality of casing side walls (108) to provide passage for the TCF to flow through the plurality of prismatic cells (112). The bottom casing plate (138) is configured to be positioned at bottom surface of the battery compartment (102), to provide support to the plurality of casing side walls (108). The signal connector (140) is configured to be positioned on the battery casing (104), to provide passage for the signal to be transmitted to other device or received by other devices.
[0078] In one embodiment, the bottom casing plate (138) is made of a material selected from a group of materials of aluminium material, plastic material, steel material, or any other metallic material. The bottom casing plate (138) is welded to all of the plurality of casing side walls (108) to form a sealed interface. In another embodiment, each of the plurality of casing side walls (108) and the bottom casing plate (138) can be cast as one single piece. The choice of manufacturing process depends on the production volume.
[0079] FIG. 3 illustrates a top view of the immersion-cooled prismatic modular battery system (100), according to the embodiments disclosed herein. The immersion-cooled prismatic modular battery system (100) comprises of the top casing plate (106), the charging socket (118), the discharging port (120), and the plurality of fastener bolts (124). The plurality of fastener bolts (124) is configured to fasten the at least one casing side wall with the top casing plate (106).
[0080] FIG. 4 illustrates an inner view of the immersion-cooled prismatic modular battery system (100) with the top casing plate (106) open, according to the embodiments disclosed herein. The immersion-cooled prismatic modular battery system (100) comprises of the plurality of casing side walls (108), the plurality of prismatic cells (112), the charging socket (118), the discharging port (120), the fluid inlet (126), a plurality of separator plates (142), a thermistor control unit (144), a plurality of bus bars (146), a main fuse (148), a battery management system (BMS) (150), the other casing side walls (168), and an another compression fixture. The plurality of separator plates (142) is configured to be positioned within the battery compartment (102). The thermistor control unit (144) is configured to be positioned adjacent to the plurality of prismatic cells (112) to measure temperature of multiple points inside the prismatic battery pack. The plurality of bus bars (146) is configured to be positioned adjacent to the plurality of separator plates (142). The main fuse (148) is configured to be positioned adjacent to at least one bus bar of the plurality of bus bars (146), to accommodate fuse element. The BMS (150) is configured to manage charging and discharging of each of the plurality of prismatic cells (112).
[0081] In one embodiment, one end of the another compression fixture is configured to be directly coupled with the one end of the compression fixture (156).
[0082] In another embodiment, the plurality of separator plates (142) may be made of a material selected from a group of materials of aluminium material, plastic material, composite material, steel material, or any other metallic material.
[0083] In yet another embodiment, the another compression fixture may be made of a material selected from a group of materials of aluminium material, plastic material, steel material, or any other metallic material.
[0084] FIG. 5 illustrates a top view of the compression fixture used to compress the stack before placement of the cell stack inside the battery casing(104). The immersion-cooled prismatic modular battery system (100) comprises of the cell pull-out band (114), the plurality of compression bands (152), and the insulation sheet (154). The plurality of compression bands (152) is configured to maintain a compression force once the compression fixture (156) is required to be removed. The plurality of compression bands (152) is further configured to pack together a single prismatic battery pack or a plurality of prismatic battery packs. The insulation sheet (154) is configured to be assembled on top of the plurality of prismatic cells (112) in order to provide the thermal insulation and the electrical insulation. One of the prismatic cell in the plurality of battery packs is attached to the cell pull-out band (114) for the purpose of pulling the at least one prismatic cell out of the battery casing (104), when the plurality of prismatic cells (112) are required to be removed from the battery casing (104) pertaining to any reason. As the at least one prismatic cell from the plurality of prismatic cells (112) is removed, the compression force disappears, and the other remaining prismatic cells can be taken out by picking up. Hence the battery casing (104) in this case is reusable once each of the plurality of prismatic cells (112) get enough degraded and require replacement. This helps save numerous costs and effort, reusable and recyclable design of the battery casing (104) helps in building a greener and sustainable future.
[0085] FIG. 6 illustrates yet another inner view of the immersive-cooled prismatic modular battery system (100) with the top casing plate (106) open, according to the embodiments disclosed herein. The immersion-cooled prismatic modular battery system (100) comprises of the fluid inlet (126) and the fluid outlet (136). The battery casing (104) as shown in the immersion-cooled prismatic modular battery system (100) of FIG. 6 has three compartments through which the flow of the TCF needs to be maintained. The flow of the TCF can be assessed by classifying main inlet flow in two parts: Bottom Surface current and Side Wall current. The bottom surface current of the TCF ensures heat rejection from bottom wall of the plurality of prismatic cells (112). The flow is observed in the way shown in the FIG. 6 with the help of solid arrows. The bottom surface current is configured to provide thermal control to the bottom surface of the plurality of prismatic cells (112). The second part of the inlet flow flows alongside walls of the at least one prismatic cell and in the plurality of flow channels (110) of the battery casing (104) specially designed for the effect. A cutout made in three compartments separating walls facilitates a side wall current flow. The side wall current is in contact with the side surface of cells through which heat rejection is observed. The side wall current flow is depicted in the FIG. 6 by line arrows.
[0086] FIG. 7A illustrates an isometric view of an immersion-cooled prismatic modular battery system (700A) with the top casing plate (106) opened, according to the embodiments disclosed herein. The immersion-cooled prismatic modular battery system (700A) comprises of the battery compartment (102), the fluid inlet (126), the fluid outlet (136), and the bottom casing plate (138). The TCF is sealed reliably inside working volume of the immersion-cooled prismatic modular battery system (100). The immersion-cooled prismatic modular battery system (700A) is designed with minimum sealing surface to minimize the probability for seal failures and make reworking process easier. This is done by welding all the edges of the battery casing (104) except those positioned adjacent to the top casing plate (106). The flow of the TCF around the surface of the plurality of prismatic cells (112) is depicted by line arrows directed towards the bottom casing plate (138).
[0087] FIG. 7B illustrates another isometric view of an immersion-cooled prismatic modular battery system (700B) with the top casing plate (106) opened, according to the embodiments disclosed herein. The immersion-cooled prismatic modular battery system (100) comprises of the fluid inlet (126) and the fluid outlet (136). The fluid inlet (126) is configured to provide the passage for the TCF to flow in a controlled direction. As shown in FIG. 7B, the TCF flows through the surface of the plurality of prismatic cells (112). The fluid outlet (136) is configured to be positioned on the at least one casing side wall to provide passage for the TCF to flow out of the battery compartment (102). The flow of the TCF around the surface of the plurality of prismatic cells (112) is depicted by line arrows directed towards inside of the battery compartment (102).
[0088] FIG. 8 illustrates a side view of the immersion-cooled prismatic modular battery system (100), according to the embodiments disclosed herein. The TCF has a high flash point which negates the possibility of fire in case of thermal runaway. Hence, the immersion-cooled prismatic modular battery system (100) of FIG. 8 is designed with active temperature control capabilities and the integrated refrigeration cycle (100D) aims to have distinguished life cycles and power-taking and dispensing capabilities.
[0089] FIG. 9 illustrates a sectional view of the immersion-cooled prismatic modular battery system (100), according to the embodiments disclosed herein. The immersion-cooled prismatic modular battery system (100) as shown in FIG. 9 does not involve use of cell modules. The plurality of prismatic cells (112) are configured to be open in the prismatic battery pack without requiring any structural parts that pack any number of prismatic cells together to make a cell module. This leads to reduction in battery weight and parts. The reduction in the number of parts corresponds to a design of the immersion-cooled prismatic modular battery system (100) that is simple for production assembly process and its supply chain. The cell-to-pack architecture of the present invention ensures best packing efficiency. The packing efficiency of the prismatic battery pack corresponds to maximum distance covering capacity, on a full-charged battery of four-wheeler vehicles.
[0090] Mass fraction of the prismatic battery pack is defined as a ratio of weight of each of the plurality of cells (112) in the prismatic battery pack to weight of the prismatic battery pack itself. The mass fraction of the prismatic battery pack corresponds to the packing efficiency of the prismatic battery pack. The packing efficiency greatly depends on the way how the plurality of prismatic cells (112) are packed in the prismatic battery pack with minimum occupying space. The embodiment of the immersion-cooled prismatic modular battery system (100) as shown in FIG. 9 comprises of the prismatic battery pack possessing the mass fraction of 0.83.
[0091] In one embodiment as per FIG. 9, the design of the immersion-cooled prismatic modular battery system (100) of the present invention uses laser welding as a method to bond cell tap and bus bar with the cell electrode. The welding of taps and bus bars allow reliable bond with a reduced weight due to absence of numerous fasteners.
[0092] In another embodiment as per FIG. 1D, the plurality of prismatic cells (112) are configured to function at a particular range of temperatures for optimum and healthy performance. For this purpose, the temperature of the plurality of prismatic cells (112) needs to be heated up, when the plurality of prismatic cells (112) are cooler than required temperature range, or cooled down when the temperature of the plurality of prismatic cells (112) exceeds the required temperature range. The cooling down is achieved by the typical refrigeration cycle (100D) while heating up is done by integrating the heater unit (164) into the refrigeration cycle (100D).
[0093] In some embodiments, the heater unit (164) may be configured to be integrated with the refrigeration cycle (100D) of the immersion-cooled prismatic modular battery system (100).
[0094] In an alternate embodiment, a refrigerant is provided which is configured to expand in the chiller unit (132), while the TCF circulating in the battery compartment (102) is made to pass through the chiller unit (132). The chiller unit (132) is configured to work as a heat exchanger where the TCF can be cooled or heated up.
[0095] FIG. 10 illustrates an isometric view of a stacked configuration or a stack (1000) of compressed cells after removing the compression fixture (156), according to the embodiments disclosed herein. This stack (1000) is then placed inside the battery casing (104) and the compression bands (152) are cut. After cutting the compression bands (152), the cell stack (1000) relaxes partially and maintains a compression force against the plurality of casing side walls.
[0096] FIG. 11 illustrates another sectional view of the immersion-cooled prismatic modular battery system (100), according to the embodiments disclosed herein. The immersion-cooled prismatic modular battery system (100) comprises of a bottom flow configurator (109) configured to form a plurality of second flow channels (111) on the bottom of the battery casing (104), while also providing electrical insulation between the battery casing (104) and the plurality of prismatic cells (112).
[0097] In an embodiment, the bottom flow configurator (109) is, but not restricted to, made of a material selected from a group of materials of Nylon, Acrylonitrile Butadiene Styrene (ABS), Delrin, Mica, FR4, or any other Fire Resistant material or Electrically Insulating material.
[0098] In one embodiment, the plurality of second flow channels (111) is configured to allow the flow of temperature control fluid (TCF) in the controlled direction.
[0099] FIG. 12 illustrates another cross-sectional view of the immersion cooled prismatic modular battery system (100), according to the embodiments disclosed herein. The immersion cooled prismatic modular battery system (100) comprises of the bottom flow configurator (109) configured to form the plurality of second flow channels (111). The plurality of second flow channels (111) are the channels on the bottom of the battery casing (104), which allows a passage for the TCF to flow through. The TCF can be any dielectric coolant like a silicon based coolant, a mineral oil or any other fluid which has a high dielectric constant and does not conduct electricity.
[00100] The immersion-cooled prismatic modular battery system (100) of the present invention is configured to modulate temperature of the plurality of prismatic cells (112), in order to facilitate proper functioning of the plurality of prismatic cells (112). The immersion-cooled prismatic modular battery system (100) of the present invention comprises the battery casing (104) in which the plurality of flow channels (110) facilitate flow of the TCF in the controlled direction to attain temperature control of each of the plurality of prismatic cells (112). The immersion-cooled prismatic modular battery system (100) of the present invention has a simple design configuration, and the battery casing (104) is configured to be reusable once each of the plurality of prismatic cells (112) get enough degraded and require replacement. The immersion-cooled prismatic modular battery system (100) of the present invention further has a simple structure and can be manufactured with minimum process steps. The immersion-cooled prismatic modular battery system (100) of the present invention is cost-effective, requires less efforts, reusable, and recyclable, and helps in building the greener and sustainable future.
[00101] Several modifications and additions are introduced to make the immersion-cooled prismatic modular battery system (100) more tolerant to variance like changes in the number of prismatic cells, the number of prismatic battery packs, the number of designed flow channels, and the number of casing side walls. Moreover, entire operational design of the immersion-cooled prismatic modular battery system (100) comprises independent electronic and mechanical components arranged with each other in a manner, such that each component work seamlessly to achieve advantages of proper functioning of the prismatic cells, accommodating bloating of the prismatic cells, facilitating the flow of the TCF in the controlled direction to attain temperature control of each of the prismatic cells, maintaining the uniform level of the compressive load on the prismatic cells, facilitating effective cooling of the prismatic cells, high packing efficiency and many other significant advantages as aforementioned above that has not been achieved by past prismatic battery cell based systems or other cell architectures.
[00102] Various modifications to these embodiments are apparent to those skilled in the art from the description. The principles associated with the various embodiments described herein may be applied to other embodiments. Therefore, the description is not intended to be limited to the embodiments but is to be providing broadest scope of consistent with the principles and the novel and inventive features disclosed or suggested herein. Accordingly, the invention is anticipated to hold on to all other such alternatives, modifications, and variations that fall within the scope of the present invention and appended claims.

REFERENCE NUMERALS FOR DRAWINGS
(100) – Immersion-Cooled Prismatic Modular Battery System
(102) – Battery Compartment
(104) – Battery Casing
(106) – Top Casing Plate
(108) – Plurality of Casing Side Walls
(109) – Bottom Flow Configurator
(110) – Plurality of First Flow Channels
(111) – Plurality of Second Flow Channels
(112) – Plurality of Prismatic Cells
(114) – Cell Pull-Out Band
(116) – Compressible Foam
(118) – Charging Socket
(120) – Discharging Port
(122) – Air-Bleed Vent
(124) – Plurality of Fastener Bolts
(126) – Fluid Inlet
(128) – Compressor Unit
(130) – Radiator Unit
(132) – Chiller Unit
(134) – Pump
(136) – Fluid Outlet
(138) – Bottom Casing Plate
(140) – Signal Connector
(142) – Plurality of Separator Plates
(144) – Thermistor Control Unit
(146) – Plurality of Bus Bars
(148) – Main Fuse
(150) – Battery Management System (BMS)
(152) – Plurality of Compression Bands
(154) – Insulation Sheet
(156) – Compression Fixture
(158) – Plurality of Compression Bolts
(160) – Expandable Foam
(162) – Sealing Gasket
(164) – Heater Unit
(168) – Other Casing Side Walls

, C , Claims:We Claim:
1. An immersion-cooled prismatic modular battery system (100), comprising:
a battery compartment (102), characterized in that:
a battery casing (104) having a top casing plate (106), a plurality of casing side walls (108), and a plurality of flow channels (110,111), wherein the plurality of flow channels (110,111) is configured to allow flow of temperature control fluid (TCF) in a controlled direction;
a plurality of prismatic cells (112) configured to be positioned on the battery casing (104), wherein the plurality of prismatic cells (112) is configured to be tightly coupled with the battery casing (104), and at least one prismatic cell is configured to be attached to a cell pull-out band (114); and
a compressible foam (116) configured to accommodate the plurality of prismatic cells (112) and maintain a uniform level of compressive load on the plurality of prismatic cells (112), through the battery casing (104),
wherein the TCF is configured to move around surface of each of the plurality of prismatic cells (112) through a pump (134), and collect thermal energy from each of the plurality of prismatic cells (112), wherein the battery casing (102) is configured to allow the TCF to absorb heat from each of the plurality of prismatic cells (112) before the TCF leaves the battery casing (102) and entering a chiller unit (132), wherein the chiller unit (132) is configured to exchange heat between the TCF and a refrigerant, and the heat is configured to be released in environment through a radiator unit (130).

2. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises a charging socket (118) configured to be positioned on at least one casing side wall of the plurality of casing side walls (108), to provide charging of the plurality of prismatic cells (112).

3. The immersion-cooled prismatic modular battery system (100) as claimed in claim 2, wherein the system (100) comprises a discharging port (120) configured to be positioned on the at least one casing side wall of the plurality of casing side walls (108), to provide discharging of the plurality of prismatic cells (112).

4. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises an air-bleed vent (122) configured to be positioned on a surface of the top casing plate (106), to provide passage for air to be bled during filling of the TCF.

5. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises a plurality of fastener bolts (124) configured to be positioned on the top casing plate (106) to fasten the at least one casing side wall with the top casing plate (106).

6. The immersion-cooled prismatic modular battery system (100) as claimed in claim 5, wherein the system (100) comprises a fluid inlet (126) configured to be positioned on an another casing side wall to provide passage for the TCF to flow through the plurality of prismatic cells (112).

7. The immersion-cooled prismatic modular battery system (100) as claimed in claim 2, wherein the system (100) comprises a fluid outlet (136) configured to be positioned on the at least one casing side wall to provide passage for the TCF to flow out of the battery compartment (102).

8. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises a compressor unit (128) configured to be connected with the radiator unit (130) and cool the TCF flowing through the plurality of prismatic cells (112), to cool the plurality of prismatic cells (112).

9. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises of a bottom casing plate (138) configured to be positioned at bottom surface of the battery compartment (102), to provide support to the plurality of casing side walls (108).

10. The immersion-cooled prismatic modular battery system (100) as claimed in claim 2, wherein the system (100) comprises of a signal connector (140) configured to be positioned on the battery casing (104), to provide passage for the signal to be transmitted to other device or received by other devices.

11. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises of a plurality of separator plates (142) configured to be positioned within the battery compartment (102).

12. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises of a thermistor control unit (144) configured to be positioned adjacent to the plurality of prismatic cells (112) to measure temperature of multiple points inside a prismatic battery pack.
s
13. The immersion-cooled prismatic modular battery system (100) as claimed in claim 12, wherein the system (100) comprises of a plurality of bus bars (146) configured to be positioned adjacent to the plurality of separator plates (142) to connect the plurality of separator plates (142).

14. The immersion-cooled prismatic modular battery system (100) as claimed in claim 13, wherein the system (100) comprises of a main fuse (148) configured to be positioned adjacent to at least one bus bar of the plurality of bus bars (146), to accommodate fuse element.

15. The immersion-cooled prismatic modular battery system (100) as claimed in claim 14, wherein the system (100) comprises a battery management system (150) configured to manage charging and discharging of the plurality of prismatic cells (112).

16. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises an insulation sheet (154) configured to be positioned adjacent to the cell pull-out band (114) to provide electrical insulation and thermal insulation to the plurality of prismatic cells (112).

17. The immersion-cooled prismatic modular battery system (100) as claimed in claim 16, wherein the system (100) comprises a plurality of compression bands (152) configured to be positioned adjacent to the insulation sheet (154) to compress the plurality of prismatic cells (112) in a stacked configuration.

18. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises a compression fixture (156) configured to be directly coupled with the plurality of prismatic cells (112), to compress the plurality of prismatic cells (112) in a form of stacked pile and the stacked pile is compressed through a portion of the compression fixture (156).

19. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises a plurality of compression bolts (158) configured to couple one end of the compression fixture (156) with one end of another compression fixture.

20. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises an expandable foam (160) configured to be positioned below the top casing plate (106) to stop the flow of the TCF to a top surface of the battery casing (104).

21. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the system (100) comprises a sealing gasket (162) configured to be mounted on the at least one casing side wall to seal mating surfaces between the top casing plate (106) and respective side plates.

22. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein system (100) comprises a heater unit (164) configured to be connected to the chiller unit (132) and heat the TCF.

23. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the top casing plate (106) and the bottom casing plate (138) are made of a material selected from a group of materials of aluminium material, plastic material, steel material, or any other metallic material.

24. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the battery casing (104) is made of a material selected from a group of materials of aluminium material, plastic material, steel material, composite material, or any other metallic material.

25. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the plurality of casing side walls (108) are prepared using extrusions, and the plurality of flow channels (110) within the extrusions allow the passage for the TCF to flow through a prismatic battery pack.

26. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the battery casing (104) comprises a bottom flow configurator (109) composed of an FR4 material, Delrin material, ABS material, or any other fire-resistant and electrically insulating material to form the plurality of flow channels (110) for the TCF to flow through the prismatic battery pack.

27. The immersion-cooled prismatic modular battery system (100) as claimed in claim 1, wherein the plurality of casing side walls (108) is made of a material selected form a group of materials of Aluminium,
Steel, Plastic Composite or any other suitable structural material.