Claims:We Claim:
1. An electrical energy storage device for reducing heat dissipation in energy sources of a 1 electric vehicle, wherein said electrical energy storage device comprises: 2
a plurality of cells (102) that are arranged circularly in parallel connection on a 3 plurality of first frames (104) to form a plurality of blocks (110), wherein said plurality of 4 blocks (110) are electrically connected with each other in a series connection on a plurality of 5 second frames (106) to form a plurality of batteries (112), wherein the plurality of batteries 6 (112) is connected in a parallel connection to form a battery assembly; and 7
a thermal exchange material (108) that is adapted to enclose a central cell of said 8 plurality of cells (102) in each of said plurality of blocks (110), wherein said thermal 9 exchange material (108) reduces heat dissipation from the surroundings of said plurality of 10 cells (102) by covering the heat generating tab between said plurality of cells (102). 11
2. The electrical energy storage device as claimed in claim 1, comprises 1
a parallel connector that connects said plurality of cells (102) with each other in the 2 parallel connection; and 3
a serial connector that connects said plurality of blocks (110) with each other in the 4 series connection. 5
3. The electrical energy storage device as claimed in claim 1, wherein said battery assembly 1 is placed inside a thermally conductive cylindrical plastic casing (202) which forms an outer 2
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structure of said battery assembly, wherein said battery assembly covered with a layer of 3 circular thermally conductive absorbent material. 4
4. The electrical energy storage device as claimed in claim 3, wherein the thermally 1 conductive cylindrical plastic casing (202) is comprised of two parts: (i) an upper casing lid 2 (206), and (ii) a bottom casing container (208). 3
5. The electrical energy storage device as claimed in claim 4, wherein said bottom casing 1 container (208) comprises a plurality of perforated vents on the circumference of said bottom 2 casing container (208), wherein said bottom polymer on the interior of said bottom casing 3 container (208) to intake a cool air and release hot air. 4
6. The electrical energy storage device as claimed in claim 4, wherein said bottom casing 1 container (208) comprises (i) a circular hard shock resistive foam at an interior of said 2 bottom casing container (208) to form a bottom base for said battery assembly and (ii) a 3 plurality of ribs for providing structural strength and heat dissipation. 4
7. The electrical energy storage device as claimed in claim 1, wherein said central cell 1 adapted with two metallic tubes (114) that comprises storage cavities, wherein said metallic 2 tubes (114) are placed around the boundary wall of heat source and separated by an 3 insulation foam for prevention of short circuiting. 4
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8. The electrical energy storage device as claimed in claim 4, wherein said upper casing lid 5 (206) comprises an inverted cylindrical lid for providing mechanical stability and a gripping 6 handle for reducing stress while carrying said battery assembly. 7
9. The electrical energy storage device as claimed in claim 1, wherein said battery assembly 1 is held on to a carrier base (210) that replicates a structure of sun and planetary, in which 2 equally spaced said plurality of blocks (110) are arranged around a central block, wherein the 3 carrier base (210) closes a layer of said plurality of blocks (110), and being held internally by 4 a plurality of threaded tubed pillars (116) which are fastened by bolts from both sides and 5 acts as a standing support for said battery assembly. 6
10. The electrical energy storage device as claimed in claim 9, wherein the carrier base (210) 1 comprises a shelled extruding on the interior surface for creating a groove and for providing 2 a spacing for connections. , Description:The embodiments herein generally relate to a energy source, and more 5 particularly, to a battery pack with significant improvements for reducing heat dissipation.
Description of the Related Art
[001] An Electric Vehicle is advancement to conservation of energy sources. In order to move forward and change the conventional energy sources required to power an automobile, a lot of factors needs to be examined for the conceptual and practical based 10 results to ensure ease of human needs. The foremost and lighthouse of an electric vehicle is basically, a battery that powers the system. The conventional automobile uses a 12V lead-acid battery provides a revolutionary energy to the engine and other accessories of the vehicle. In conjugation, to Electrical vehicle structure the battery is the only energy source for conversion of stored energy into motion energy or electric energy. So, the battery has to 15 be well designed and effective enough for the absolute complete cycle. Advancements in battery chemistry, battery packing, battery usage and thermal capabilities has led to the wide-scale usage of lithium-ion batteries. Advantages of using a lithium-ion battery are superior in size and weight, better resilience, high specific energy density, longer lifecycle, lower maintenance and higher efficiency. One of the problems in the usage of lithium-ion battery 20 packs on an electric or electric vehicle is to prevent thermal runaway or internal heating. If a lithium-ion battery pack exceeds temperature limits set, then the risk of an explosion or burning becomes significantly higher. So, a battery has to be thermally controlled. Generally,
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for overcoming the challenges, the following mentioned measures are executed: Battery Thermal Management System, The specialized arrangement of cell packaging, Internal Battery cooling through a specialized arrangement of cells with respect to a thermal exchange material (heat exchange material) and external cooling via the streamlined body of the vehicle as per aero dynamical arrangement in the chassis. 5
[002] As discussed above electrification is the most efficient and effective way for a cleaner environment and a viable approach to sustainable development. Electric vehicles including electric vehicles, plug-in electric vehicles and pure battery electric vehicles will dominate the clean vehicle market. The key element to this revolutionary change is effective utilization of stored energy. Electric vehicle batteries are quite different from those used in 10 various electronic devices. They are required to handle high power and high energy capacity within a limited weight and space. Extensive research and investments have been given to the advanced battery technologies. The electric vehicle battery modelling will be introduced in such a way that it is suitable for power engineers to appreciate the use of its power electronic interfacing converter design, battery management and system level studies. The performance 15 of battery changes as its operating conditions varies which is also in direct co-relation with temperature. For an electric vehicle, the load varies with time corresponding to input and output values dynamically. This gives sudden rise and fall in voltage and discharges varying transiently. The sudden rise and fall increase the temperature of the battery through cell-to-cell heat transfers. The temperature affects its performance, both in the short and the long 20 run. The rise in temperature may also reduce the battery life, and may lose significant utilizable energy in the form of heat. So, the battery pack performance directly affects range, power for acceleration, economy and charge acceptance during energy recovery by any
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means. Factors affected by the temperature are: Operation of the electrochemical system, Round trip efficiency, Charge acceptance, Power and energy availability and Reliability. In order to excel over the foregoing mentioned factors, the temperature has to be kept in accordance. Different cooling methods are widely adopted by the manufacturers for overcoming the temperature issue. Some of them can be too bulky, costly and consume 5 energy from the same battery pack.
[003] The performance of lithium-ion battery cells is greatly impacted by their temperature, as they suffer from Goldilocks effect. They do not perform well when too hot or too cold, which can lead to permanent and extreme damage of cells or accelerated degradation. Therefore, in addition to cooling, heating of the cells may also be required at 10 lower ambient temperatures to prevent damage during fast charging when the cells are too cold, this is because the internal resistance of the cells rises when they are cold. The common types of battery thermal management solutions: Convection to air either passively or forced, cooling by flooding the battery with a dielectric oil which is then pumped out to a heat exchanger system, cooling by circulation of water-based coolant through cooling 15 passages within the battery structure, cooling by drilling metal tubes into the cells and circulating air through it and making vents in the battery pack to circulating a fluid into the system.
[004] The above-mentioned cooling systems are bulky, costly, unsafe and very complicated. This increases the overall cost and affects the manufacturability and assembly 20 of the battery pack. Lithium batteries connections get disturbed and many failure incidents have been noted in the past history due to the short circuit in the battery. Complication can be one definite reason for the failures of the lithium batteries. Accordingly, there remains a need
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for an arrangement of cells in order to overcome the above-mentioned complexities without any forced cooling technique.
SUMMARY
[005] In view of the foregoing, an embodiment herein provides an electrical energy storage device for reducing heat dissipation in energy sources of a electric vehicle. The 5 device includes one or more cells and a thermal exchange material. The one or more cells that are arranged circularly in parallel connection on one or more first frames to form one or more blocks. The one or more blocks are electrically connected with each other in a series connection on one or more second frames to form one or more batteries. The one or more batteries are connected in a parallel connection to form a battery assembly. The thermal 10 exchange material that is adapted to enclose a central cell of the one or more cells in each of the one or more blocks. The thermal exchange material reduces heat dissipation from the surroundings of the one or more cells by covering the heat generating tab between the one or more cells.
[006] In an embodiment, the device includes a parallel connector that connects the 15 one or more cells with each other in the parallel connection and a serial connector that connects the one or more blocks with each other in the series connection.
[007] In another embodiment, the battery assembly is placed inside a thermally conductive cylindrical plastic casing which forms an outer structure of the battery assembly. The battery assembly covered with a layer of circular thermally conductive sponge rubber. 20
[008] In yet another embodiment, the thermally conductive cylindrical plastic casing includes two parts: (i) an upper casing lid, and (ii) a bottom casing container.
[009] In yet another embodiment, the bottom casing container includes one or more
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perforated vents on the circumference of the bottom casing container. The bottom casing container is covered by a microporous membrane of polymer on the interior of the bottom casing container.
[0010] In yet another embodiment, the bottom casing container includes (i) a circular hard shock resistive foam at an interior of the bottom casing container to form a bottom base 5 for the battery assembly and (ii) one or more ribs for providing structural strength and heat dissipation.
[0011] In yet another embodiment, the central cell adapted with two metallic tubes that includes storage cavities. The metallic tubes are placed around the boundary wall of heat source and separated by insulation foam for prevention of short circuiting. 10
[0012] In yet another embodiment, the upper casing lid includes an inverted cylindrical lid for providing mechanical stability and a gripping handle for reducing stress while carrying the battery assembly.
[0013] In yet another embodiment, the battery assembly is held on to a carrier base that replicates a structure of sun and planetary, in which equally spaced the one or more 15 blocks are arranged around a central block. The carrier base closes a layer of the one or more blocks, and being held internally by one or more threaded tubed pillars which are fastened by bolts from both sides and acts as a standing support for the battery assembly
[0014] In yet another embodiment, the carrier base includes a shelled extruding on the interior surface for creating a groove and for providing a spacing for connections. 20
[0015] The battery assembly may have the advantage of reduced heat transfer for cell-to-cell due to convection and radiation. The presented design construction makes it resistant to physical damages. The design of the components and packaging of battery offers
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reduced weight of the battery pack. Manufacturing and assembly of the battery pack design allow an ease in building modules. Identification of issues in connections or short-circuit can be easily rectified. This intelligent circular battery is reliable to last longer than normal conventional batteries. Better thermal management without external power consuming devices or arrangements perceives effective usable life of the battery. The transient thermal 5 analyzation of the design validation on the use of the product-design process was able to estimate maneuverability of the battery pack with respect to heat flow by conduction and convection including the effects of thermal resistance layer, time-dependent charge/discharge, temperature dependent material properties, heat power, and other boundary conditions. The above design offers fulfilment of all the requirements in an advanced 10 systematic arrangement of cells, which combines ease of use with high computational power, and ensures the better thermal flow of heat within the battery pack while being discharged and charged. The conventional and circular battery were considered, with respect to which the above design shows the improvement in temperature variation of around 31.5% that proves the advanced effects of the design invention without using any external forced 15 cooling. So, the arrangement gives better temperature distribution of the fluid inside the battery pack as well as the cell-to-cell heat transfers, by providing optimal space between cells.
[0016] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the 20 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
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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
[0017] The embodiments herein will be better understood from the following detailed 5 description with reference to the drawings, in which:
[0018] FIG. 1 illustrates an electrical energy storage device for reducing heat dissipation in energy sources of electric vehicles according to an embodiment herein; and
[0019] FIG. 2 illustrates an exploded view of electrical energy storage device according to an embodiment herein; 10
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0020] The embodiments herein and the various features and advantageous details thereof are explained more carefully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not 15 unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein. 20
[0021] Accordingly, there remains a need for an arrangement of cells in order to reduce cell-to-cell thermal interactions in the forms of heat transfer like conduction, convection and radiation without any forced cooling technique. Explaining now the energy
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storage through a cell technique.
[0022] Referring now to the drawings, and more particularly to FIGS. 1 through 2, where similar reference characters denote corresponding features consistently throughout the figures, there are shown the preferred embodiments.
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[0023] FIG. 1 illustrates an electrical energy storage device for reducing heat dissipation in energy sources of electric vehicles according to an embodiment herein. The assembly includes a plurality of cells 102, a plurality of first frames 104, a plurality of second frames 106, a parallel connector (Not shown in Fig.), a serial connector (Not shown in Fig.) and a thermal exchange material 108. The plurality of cells 102 is arranged circularly on the 10 plurality of first frames 104 to form a plurality of blocks 110 in uniform spoke structure. The plurality of cells 102 is connected in parallel connection using the parallel connector. The plurality of blocks 110 electrically connected with each other in a series connection using the serial connector to form a plurality of batteries 112. In some embodiment, the serial connector connects the adjacent cells by being a circular metallic ring for uniformity of 15 discharge in plurality of blocks 110 placed at the exterior of the plurality of blocks 110. The cells are placed with an equally spaced circle pattern around the central cell for better thermal distribution placed on the plurality of first frames 104. The thermal exchange material 108 is adapted to enclose a central cell of the plurality of cells 102 in each of the plurality of blocks 110 to reduce heat dissipation from the surroundings of the plurality of cells 102 by covering 20 the heat generating tab between the plurality of cells 102. In some embodiment, the central cell adapted with two metallic tubes 114 that includes storage cavities. The metallic tubes 114 are placed around the boundary wall of heat source and separated by an insulation foam
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for prevention of short circuiting. In some embodiment, the plurality of cells 102 arranged in a circular form, around the central cell. The plurality of batteries 112 is connected parallelly to form the battery assembly.
[0024] In some embodiment, the battery may made of two or more electrochemical cells coupled together via connections through a wire or any other conductive material for 5 electrical conduction. This electrochemical cell consists of an active metal positive electrode (cathode) and a negative electrode (anode) that uses lithium preferably graphite, electrolyte, current collector and a separator. The cell can be of many shapes and sizes with different capacity. In some embodiment, the plurality of cells 102 may be of cylindrical shape, rectangular shape, or maybe a small button like. Its purpose is to store electricity as a result 10 of spontaneous chemical reactions. On discharge, cells convert chemical energy to electrical energy. A battery pack can contain several series or parallel strings of many cells.
In an embodiment, the serial connector and parallel connector are in the circular form factor. The battery assembly covered with a layer of circular thermally conductive polymer. In an embodiment, the upper casing lid packs the said battery assembly, structured in a way to 15 withhold mechanical stability for reducing stress while carrying said battery assembly, with a gripping handle. Each of the plurality of blocks has central cell adapted with two metallic tubes 114 that comprises storage cavities. The metallic tubes 114 are placed near the tabs, around the boundary wall of heat source and separated by insulation foam for prevention of short circuiting. The plurality of metallic tubes 114 placed around the plurality of cells acts 20 like a container which is filled up with thermal exchange material for adoption of heat transfer from cell through conduction. This thermal exchange material is actively taking heat
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energy to change its state of matter which is endothermally absorbing the heat to extent of its phase of latent heat.
[0025] In an embodiment, the battery assembly is held on to a carrier base that replicates a structure of sun and planetary in which equally spaced the plurality of blocks are arranged around a central block. The carrier base closes a layer of said plurality of blocks and 5 being held internally by a plurality of threaded tubed pillars 116 which are fastened by bolts from both sides and acts as a standing support for said battery assembly. The Carrier base comprises a shelled extruding on the interior surface for creating a groove and for providing spacing for connections.
[0026] FIG. 2 illustrates an exploded view of electrical energy storage device 10 according to an embodiment herein. The thermally conductive cylindrical plastic casing 202 includes an upper casing lid 206 and a bottom casing container 208. The battery assembly is covered with a layer of circular thermally conductive sponge rubber 204. The upper casing lid 206 may include an inverted cylindrical lid for providing mechanical stability and a gripping handle for reducing stress while carrying the battery assembly. The bottom casing 15 container 208 includes a circular hard shock resistive foam and a plurality of ribs. The circular hard shock resistive foam is placed at an interior of the bottom casing container 208 to form a bottom base for the battery assembly. The plurality of ribs for providing structural strength and heat dissipation. In an embodiment, the bottom casing container 208 includes a plurality of perforated vents on the circumference of the bottom casing container 208. The 20 bottom casing container 208 is covered by a microporous membrane of polymer on the interior of the bottom casing container 208. In some embodiment, the microporous membrane of polymer may in take cool air and eject hot air, when the vehicle is in motion,
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while when stationary, it ejects hot air to the environment.
[0027] In some embodiment, the battery assembly is held on to a carrier base 210 that replicates a structure of sun and planetary which spaced the plurality of blocks 110 are arranged around a central block. The carrier base 210 includes a shelled extruding on the interior surface for creating a groove and for providing a spacing for connections. In some 5 embodiment, the carrier base 210 closes a layer of the plurality of blocks 110, and being held internally by a plurality of threaded tubed pillars 116 which are fastened by bolts from both sides and acts as a standing support for the battery assembly. The battery assembly is held together by two circular discs that are standing on to the plurality of threaded tubes, bolting the assembly of the individual blocks 110. In some embodiment, the circular disc is located 10 at the bottom of the stand is resting on a grooved rack extruded on the internal side of the battery casing to provide a base for the external stand. The plurality of cells 102 supported by quadrilateral ribs with the groove rack to provide mechanical strength.
[0028] In some embodiment, the metallic tubes 114 absorb heat from the surrounding cells and transfer the observed heat to the thermal exchange material 108, which in turn 15 absorbs and converts that heat energy to change its state of matter. In some embodiment, the thermal exchange material 108 may have good melting properties, and high heat of fusion, prior to which latent heat storage is a major characterization for changing its state of matter with changes in temperature ranges. In some embodiment, the device reduces cell-to-cell thermal interactions via forms of heat transfer like conduction, convection and radiation to 20 reduce them through a specialized arrangement of cells without any forced cooling technique.
[0029] The foregoing description of the specific embodiments will so fully reveal the
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general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology 5 employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope.