Description:TECHNICAL FIELD
[0001] The present subject matter relates to a battery module. More particularly and not exclusively, it pertains to heat dissipation in the battery module. The present application is a patent of addition with respect to the patent application number 202041031643.
BACKGROUND
[0002] In recent years, rechargeable energy storage devices have been widely used as an energy source for a number of electronic and electrical units, hybrid and electric vehicles. Commonly used rechargeable energy storage devices include, for example, nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium rechargeable batteries. Lithium rechargeable energy storage devices are predominantly used in electric and hybrid vehicles because they are rechargeable, they can be made in a compact size with large capacity, they have a high operation voltage, and they have a high energy density per unit weight.
[0003] An existing energy storage device comprises one or more energy storage cells, such as, lithium-ion battery cells enclosed within a casing. The electrochemical reactions with the lithium-ion battery cells are responsible for the voltage and the current generated by the energy storage device. Also, during charging of the energy storage device, electrochemical reactions occur within the lithium-ion battery cells. These electrochemical reactions are highly exothermic, and the lithium-ion battery cells tend to heat up during the course of normal operation. The increased temperatures of the lithium-ion battery cells degrade the electrical performance of the energy storage device and may lead to catastrophic failure of the energy storage devices.
[0004] The energy storage device comprising the lithium-ion battery cells finds application as an energy source in electric vehicle or a hybrid electric vehicle. The energy storage device in the electric or hybrid electric vehicle requires cooling for continuous performance and durability with good health of the lithium-ion battery cells. However, it is seen that the range of the vehicle reduces due to temperature rise of the battery cells, and in worst case scenarios there is always a probability of thermal runaway in the energy storage device. Thermal runaway in energy storage device occurs when the cells of the energy storage device experience an uncontrolled increase in temperature that can lead to catastrophic failure of the energy storage devices. The increased temperature and pressure can cause the energy storage device to rupture or explode, releasing toxic chemicals and causing fire. Further, charging immediately after riding/driving the vehicle may not be possible due to temperature rise in the battery module even by using fast charging chargers.
[0005] Thus, there is a need to effectively dissipate the generated heat, efficiently cool the lithium-ion battery cells of the energy storage device to maintain efficient performance and longevity of the energy storage device, as well as ensure arresting of propagation of fire within the energy storage device to prevent thermal runaway.
BRIEF DESCRIPTION OF DRAWINGS
[0006] The detailed description is described with reference to the accompanying figures. The same numbers are used throughout the drawings to reference like features and components.
[0007] Fig.1 exemplarily illustrates a perspective view of a battery module, as per an embodiment of the present invention;
[0008] Fig. 2 exemplarily illustrates a partial exploded perspective view of the battery module exemplarily illustrated in Fig. 1;
[0009] Fig. 3 exemplarily illustrates a perspective view of a thermal barrier assembly illustrated in Fig. 2;
[00010] Figs. 4 exemplarily illustrate a plan view of the thermal barrier assembly illustrated in Fig.3, encompassing cells;
[00011] Figs. 5 exemplarily illustrate a perspective view of a thermal barrier assembly encompassing a first plurality of cells;
[00012] Figs. 6 exemplarily illustrates a plan view of the thermal barrier assembly illustrated in Fig. 5 and an enlarged view of a detail of the plan view, respectively;
[00013] Fig. 7 exemplarily illustrates an exploded view of the thermal barrier assembly encapsulating at least one cell positioned in at least one row; and
[00014] Fig. 8 exemplarily illustrate a plan view of the thermal barrier assembly illustrated in Fig.3, encompassing the cells 104.
DETAILED DESCRIPTION OF THE INVENTION
[00015] In case of drastic increase in temperatures of the cells of the energy storage device, the cells may ignite and cause fire. The material of the housing of the cells and presence of air between the cells and inner surface of the casing may propagate the fire to all the cells in the energy storage device, leading to a catastrophic failure of the energy storage device and the product, such as, a vehicle employing it. Many energy storage devices are provided with a sacrificial member that melts down and creates a space between the cells or rows of cells to arrest such propagation of fire. However, probability of the sacrificial member being non-functional at the time of need makes this mechanism not effective. Despite employing the sacrificial member, there still exists a need for extracting heat from individual cells to reduce the probability of drastic increase in the temperatures of the cells.
[00016] In an implementation for cooling of the energy storage device, and in turn the lithium-ion battery cells, a heat exchange member in thermal contact with the casing of the energy storage device is used and forced convection is employed. The heat dissipated from the lithium-ion battery cells has to traverse through air-filled gap between the cells and the casing. The heat transfer between the battery cells and the casing is not efficient since the air is a poor conductor of heat. In order to ensure that the heat is effectively dissipated from the battery cells, it is essential to ensure that the heat generating battery cells are reliably secured to be in thermal contact with the heat exchange member proximal to the casing. Another existing implementation employs liquid cooling for thermal management in the energy storage device. The energy storage device as a whole may be immersed into a liquid coolant. However, the liquid coolant is stagnant and efficiency of cooling of the energy storage device is substantially less.
[00017] Another implementation of the energy storage device involves employing coolant tubes for a liquid coolant designed around individual battery cells or a cluster of battery cells in the energy storage device. However, insertion of modular coolant tubes within the casing of the energy storage devices makes the energy storage device bulky and no longer compact for space-constrained varied applications.
[00018] The present application is a patent of addition of the patent application number 202041031643. Henceforth patent application number 202041031643 is referred as “Main application” for the purpose of brevity.
[00019] The “Main application” discloses about a battery module with a thermal barrier assembly, which is used for thermal management of the plurality of cells in the battery module. The thermal barrier assembly comprises at least one partition structure in thermal contact with the cells in the battery module for extracting heat from the cells, and at least one heat dissipating structure for dissipating the extracted heat away from the cells. The partition structure has a serpentine profile with a contour conforming to the surfaces of the adjacent cells and comprises a series of alternating crests and troughs to establish thermal contact with the cells. The thermal barrier assembly further includes a thermal shield, which is positioned between rows of cells and is in contact with at least one partition structure of each row of cells. The thermal shield is designed to arrest the propagation of heat and fire from one row of cells to adjacent rows of cells. The thermal shield is made of a material that is thermal conducting on one side and thermal insulating on the other side. This allows the shield to conduct heat away from the cells while also preventing the heat from propagating to adjacent cells. The thermal shield is also designed to be thermally conducting along its length and thermally insulating towards its thickness. This design helps to direct the heat away from the cells and towards the heat dissipating structures.
[00020] Further, the “Main application” discloses about heat dissipating structures being positioned proximal to the ends of the partition structures and are thermally coupled to them. The heat dissipating structures include at least one airflow guide on a front surface in contact with air within the casing and a planar rear surface that is thermally coupled to at least one partition structure and at least one thermal shield. The heat dissipating structures further comprise at least one extension member that extends from the planar rear surface for removably engaging with the ends of at least one partition structure and at least one thermal shield. The heat dissipating structures are designed to extract heat from the cells and dissipate it away from the battery module through the airflow guide. The extension members help to secure the heat dissipating structures to the partition structures and thermal shield to ensure efficient heat dissipation.
[00021] However, air cooling only through heat dissipation structures, can be less effective, this is because air cooling typically only removes heat from the cells that are in direct contact with the heat dissipation structures. This can lead to temperature imbalances within the battery system, creating localized hot spots. Thereby in such battery modules there is a high probability of having some cells cooler or hotter than others. This can further cause inconsistent battery performance, reduce battery life, and increase the risk of thermal runaway.
[00022] The present application discloses a subject matter that has been devised in view of the above circumstances as well as solving other problems of the known art.
[00023] The present subject matter in an embodiment, discloses a battery module having constant circulating liquid coolant within the battery module. The circulating liquid is used to extract heat from the battery cells within the battery module. In an embodiment, the battery module is made up of multiple rows of battery cells, which are enclosed within at least two zig-zag shaped partition structures from either side. The partition structure has a serpentine profile with a contour conforming to the surfaces of the adjacent cells and comprises a series of alternating crests and troughs. There is a consistent gap in between the serpentine profile of the at least two partition structures and at least one cell of the battery module, creating a channel in between. The channel encompasses at least one row of battery cells. The channel-like structure enables the liquid coolant to flow from end of the channel to another end, while being in constant contact with each cell of the battery module. As the liquid coolant flows through the channel, the liquid coolant absorbs the heat generated by each of the battery cells and carries the heat away from the cells of the battery module. This extraction of heat by the liquid coolant, helps to prevent the battery cells from overheating and reduces the risk of thermal runaway. Once the liquid coolant has passed through all the battery cells in the channel, the liquid coolant exits through an outlet.
[00024] In an embodiment, as the liquid coolant, flows out of the battery module, the liquid coolant is cooled down, because of being in contact with a heat exchanger.
[00025] In another embodiment, as the liquid coolant, flows out of the battery module, the liquid coolant is cooled down, because of being circulated through a separate cooling system.
[00026] Further, the cooled liquid is then circulated back into the battery module through an inlet, and the process starts all over again, and the liquid coolant is recirculated through multiple channels.
[00027] This continuous circulation of the liquid coolant helps to maintain a consistent temperature within the battery module, which is essential for the safe and efficient operation of the battery system. The continuous circulation of the liquid coolant also ensures that the battery cells are not subjected to extreme temperature fluctuations, which can cause damage and reduce their overall lifespan.
[00028] Further, the constant circulation of the liquid coolant is more beneficial when compared to other forms of coolants, because the liquid coolant in circulation provides more effective and efficient cooling of the battery cells within the battery module. A circulating liquid coolant can extract heat from all battery cells within the battery module, ensuring that the temperature remains consistent throughout the battery module. The continuous flow of liquid coolant also helps to distribute heat more evenly, which reduces the risk of localized hotspots that can damage the battery cells in the long run. Moreover, the use of a circulating liquid coolant provides an opportunity for the cooling system to be integrated with other components such as heat exchangers and radiators, which further enhance the cooling capacity of the overall battery. Further, such configuration is capable of aiding in improving the overall efficiency of the battery module and reduces energy loss.
[00029] The present subject matter is further described with reference to accompanying figures. It should be noted that the description and figures merely illustrate principles of the present subject matter. Various arrangements may be devised that, although not explicitly described or shown herein, encompass the principles of the present subject matter. Moreover, all statements herein reciting principles, aspects, and examples of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.
[00030] Fig.1 exemplarily illustrates a perspective view of a battery module 100, as per an embodiment of the present invention. As exemplarily illustrated, the battery module 100 comprises a casing 101 and a first end cover 102. The casing 101 is a hollow rectangular cover with open ends enclosing multiple cells and other electrical and electronic components, such as, a battery management (BMS) board (not shown) of the battery module 100. End covers 102 of the battery module 100 enables opening and closing ends of the casing 101. The casing 101 has mounting provisions (not shown) to mount the end covers, such as, the first end cover 102 and a second end cover (not shown) at the open ends of the casing 101 using attachment means. The end covers have external electrical connections of the battery module 100 for charging and discharging of the battery module 100. In an embodiment, an outer surface of the casing 101 may comprise a dovetail pattern that facilitates in easy mounting and removal of the battery module 100 in a designated space in a powered device, such as, a vehicle.
[00031] Fig. 2 exemplarily illustrates a partial exploded perspective view of the battery module 100 exemplarily illustrated in Fig. 1. The battery module 100 comprises multiple cells 104 in a thermal barrier assembly 103 positioned within the casing 101. The cells 104 are positioned between the cell holders 105 and 106. The cell holders 105 and 106 have mounting provisions for the BMS board (not shown). On one side of the casing 101, the first end cover 102 is provided and on the other side of the casing 101, a second end cover 107 seals the casing 101. The cell holders 105 and 106 have provisions to accommodate and hold the cells 104 in position. Such provisions, referred to as placeholders 106a are evenly distributed annuli in the cell holders 105 and 106 into which the cylindrical cells are inserted. The placeholders 106a may be of different shapes, such as, rectangular, square, hexagonal, etc., based on the shape of the cells 104. The placeholders 106a are evenly distributed in different rows to accommodate the cells 104 in different rows across the surface of the cell holders. 105 and 106. Each row of placeholders 106a may comprise one or more cells, such as, 104. The cells 104 in the placeholders 106a are closely packed from top and bottom by the cell holders 105 and 106. The cells 104 may be connected in series and/or parallel combination using interconnect sheets (not shown).
[00032] The cells 104 are encompassed in the thermal barrier assembly 103 of the battery module 100 and positioned in the placeholders 106a. The cells 104 with the thermal barrier assembly 103 are positioned between the cell holders 105 and 106. The thermal barrier assembly 103 extracts and dissipates the heat generated from by cells 104, away from the cells 104. The thermal barrier assembly 103 also prevents propagation of fire to cells 104 in different rows due to increased temperatures or fire. In an embodiment, the casing 101 further comprises openings on side walls for venting the accumulated heat and any gases released from the cells 104 to the outside of the battery module 100. The structure of the thermal barrier assembly 103 is described in the subsequent figures. In addition to the thermal barrier assembly 103, the battery module 100 comprises protective sheets 108 and 109 positioned on the cell holders 105 and 106. These protective sheets 108 and 109 prevent terminals of the cells 104 from coming into direct contact with the casing 101. The electrical connection between the cells 104 is made using interconnect sheet positioned on the cell holders 105 and 106. The terminals of the cells 104 are soldered to the interconnect sheets to connect them in series and parallel. In an embodiment, the protective sheets 108 and 109 is positioned above the interconnect sheets. In an embodiment, the interconnect sheet is absent and the protective sheet, such as, 108 or 109 establishes electrical connections between the cells 104, while also preventing direct contact of the terminals of the cells 104 with an inner surface of the casing 101.
[00033] Fig. 3 exemplarily illustrates a perspective view of the thermal barrier assembly 103 illustrated in Fig. 2. The thermal barrier assembly 103 comprises at least one partition structure, 301, 302 in thermal contact along a length of at least one row comprising at least one cell 104a for extracting heat from that cell 104a. The thermal barrier assembly 103 further comprises at one heat dissipating structure 304, 305 positioned proximal to at least one end 301a, 301b or 302a, 302b of the partition structure 301 and 302 and thermally coupled to the partition structure 301 and 302 to dissipate the extracted heat away from the cells 104. As used herein, “thermal contact” refers to a contact between two structures or surfaces that enables transfer of heat between the structures. Herein, the transfer of heat is primarily done by convection, or any other known modes. For the transfer of heat to take place, the structures are in physical contact with a circulating liquid coolant. The circulating liquid coolant flows in between at least two partition structures 301 and 302. As exemplarily illustrated, the cells 104 are positioned in rows, such as, 306, 307 and the thermal barrier assembly 103 includes a plurality of cells in the plurality of rows 306, 307. There are multiple cells, for example, 5 cells 104a, in each row. The thermal barrier assembly 103 comprises at least one partition structure, that is, a first partition structure 301 and a second partition 302 structure that extends along the length of the row of cells 104. Each row of cells has a corresponding first partition structure 301 and a corresponding second partition structure 302. Also, at both the ends of the partition structures 301, 302, there are two heat dissipating structures 304 and 305.
[00034] The first partition structure 301 and the second partition structure 302 are in thermal contact with a circulating liquid coolant 600 (shown in Fig. 4), which is turn is in contact with the cells 104a, 104b along the periphery of the cells 104a, 104b and extract heat from each of the cells 104a, 104b in a row 306. Herein, the circulating liquid coolant 600 is in physical contact with the cells 104a, 104b to extract heat. The partition structures 301, 302 are thermally conductive sheets with a series of alternating crests 301c, 302c (shown in Figure 7) and troughs 301d, 302d (shown in Figure 7) formed on their surface. The circulating liquid coolant 600 flows in between the partition structures 301, 302 and the neighbouring cells 104a, 104b. Since the structure of partition structures 301, 302 is of alternating crests and troughs, thereby the alternate crests and troughs aid in increasing the surface area of contact between the liquid coolant 600 and the cells 104a, 104b of the thermal barrier assembly 100, thereby further facilitating more efficient heat transfer. As the liquid coolant 600 flows through the crests 301c, 302c (shown in Figure 7) and troughs 301d, 302d (shown in Figure 7), it comes into direct contact with the cells 104a, 104b of the thermal barrier assembly 103. The increased surface area provided by the crests 301c, 302c (shown in Figure 7) and troughs 301d, 302d (shown in Figure 7) means that more of the liquid coolant 600 is in contact with the cells 104a, 104b at any given time, allowing for more efficient heat transfer. The first partition structure 301 and the second partition structure 302 are both serpentine in profile with a contour conforming to an external surface of the cylindrical cells 104a, 104b. The heat dissipating structures 304, 305 at the ends of the first partition structure 301 and the second partition structure 302 are thermally coupled to the first partition structure 301 and the second partition structure 302. The heat extracted from each of the cells 104a, 104b is transferred to the heat dissipating structures 304, 305 through the first partition structure 301 and the second partition structure 302 along with the liquid coolant 600, and the heat dissipating structures 304, 305 transfer the heat to surrounding air within the casing 101 by means of convection. The heat is thus channelized away from the cells 104a, 104b to limit conduction of heat between the cells in different rows 306, 307, thereby eliminating thermal runaway of the battery module 100.
[00035] The thermal barrier assembly 103 further comprises at least one thermal shield 303 in contact with at least one partition structure 301, 302 and extending along the length of at least one row 306 for thermally insulating at least one cell 104a in the row 306 from the plurality of cells 104c, 104d in a plurality of adjacent rows such as, 307. That is, the thermal barrier assembly 103 comprises a thermal shield 303 that runs along the length of each row 306, 307 of the cells 104. The thermal shield 303 is in contact with the first partition structure 301 and/or second partition structure 302 for thermally insulating each row 306 of cells 104a, 104b from other rows 307 of cells 104c, 104d in the placeholders 106a. The thermal shield 303 curtails the propagation of fire in the lateral direction of the cells 104 in the cell holders 105,106. In an embodiment, the partition structures 301, 302 and the thermal shield 303 may be inserted in slits in the cell holders 105, 106 next to the placeholders 106a for the cells 104 and may be supported vertically by the cell holders 105, 106. Similarly, the heat dissipating structures 304, 305 may be supported by the cell holders 105, 106 at the top and the bottom to stay intact and be vibration proof within the casing 101 of the battery module 100.
[00036] Consider there are multiple cells in each of the rows of the placeholders 106a in the cell holders 105, 106. Also, consider the cells in a first row as a first plurality of cells or first set of cells 104a, 104b and the cells in a second row as a second plurality of cells or second set of cells 104c, 104d in Fig. 3. The first set of cells 104a, 104b are in thermal contact with respective first partition structure 301 and the second partition structure 302. Similarly, the second set of cells 104c, 104d are in thermal contact with respective first partition structure (not shown) and respective second partition structure (not shown). The thermal shield 303 is positioned between the first partition structure 301 and the second partition 302 of the first set of cells 104a, 104b and the first partition structure (not shown) and the second partition structure (not shown) of the second set of cells 104c, 104d in the adjacent row. The thermal shield 303 prevents propagation of fire from the first set of cells 104a, 104b to the second set of cells 104c, 104d. The thermal shield 303 is an insulation layer wrapped over the first set of cells 104a, 104b, the second set of cells 104c, 104d, and the partition structures 301, 302. The thermal shield 303 adds extra resistance to heat to pass through the partition structures 301, 302 and thus heat is passed only along the length of the partition structures 301, 302 towards the heat dissipating structures 304, 305.
[00037] Figs. 4 exemplarily illustrate a plan view of the thermal barrier assembly 103 illustrated in Fig.3, encompassing the cells 104. As viewed in Fig. 4, there are multiple cells 104a, 104b, in row 306 and similarly multiple cells 104c, 104d in row 307 respectively and the alternating rows 306 and 307 of cells 104a, 104b and 104c, 104d are connected in series or parallel with each other.
[00038] The present subject matter in an embodiment, discloses the thermal barrier assembly 103 having constant circulating liquid coolant 600 within the battery module 100. The circulating liquid coolant 600 is used to extract heat from the battery cells 104a, 104b, 104c, 104d within the battery module 100. In an embodiment, the thermal barrier assembly 103 is made up of multiple rows of battery cells 104a, 104b, 104c, 104d, which are enclosed within at least two zig-zag shaped partition structures 301, 302 from either side. The partition structure 301, 302 has a serpentine profile with a contour conforming to the surfaces of the adjacent cells 104a, 104b, 104c, 104d and comprises a series of alternating crests 301c, 302c (shown in Figure 7) and troughs 301d, 302d (shown in Figure 7).
[00039] At both ends 301a, 301b, 302a, 302b of the partition structures 301, 302, the heat dissipating structures 304, 305 are removably attached to the partition structures 301, 302, as indicated in Fig. 3. The first set of cells 104a, 104b in the first row 306 are connected to each other in series or parallel and the second set of cells 104c, 104d in the second row (adjacent row) 307 are connected to each other in parallel or series, respectively. Between the partition structures 301, 302, of the first set of cells 104a, 104b and the adjacent partition structures (not shown) of the second set of cells 104c, 104d, the thermal shield 303 is disposed. The thermal shield 303 extends the entire length of the row 306, 307. The thermal shield 303 physically and thermally separates the first set of cells 104a, 104b from the second set of cells 104c, 104d. Similarly, such thermal shields 303 are positioned between all the rows of cells 104 in the thermal barrier assembly 103. Also, in case of overcharging, the cells that are connected in parallel are prone to thermal runaway than the cells connected in series. Consider, the first set of cells 104a, 104b are connected in series and the second set of cells 104c, 104d are connected in parallel. In case of thermal runaway, the second set of cells 104c, 104d are damaged and may cause fire. However, the thermal shield 303 between the first set of cells 104a, 104b and the second set of cells 104c, 104d prevents the spread of fire to the first set of cells. Similarly, a next thermal shield (not labeled) between the second set of cells 104c, 104d and the next adjacent rows of cells (not labeled) connected in series isolates the spread of fire laterally across the third rows of cells in the battery module. The second set of cells 104c, 104d with parallel connection are compromised, while the adjacent rows of cells are protected. The thermal shield 303 is also removably attached to the heat dissipating structures 304, 305 at its ends.
[00040] Figs. 5 exemplarily illustrate a perspective view of a thermal barrier assembly 103 encompassing a first set of cells 104a, 104b. As exemplarily illustrated in Fig. 5, the thermal shield 303 surrounds on the first set of cells 104a, 104b and forms a cell pack 401. The thermal shield 303 isolates the first set of cells 104a, 104b from the rest of the cells in the battery module 100. The thermal shield 303 is removably attached to the heat dissipating structure 305 on a rear surface of the heat dissipating structure 305. The heat dissipating structure 305 is a heat sink that dissipates and transfers the heat generated by the cells to the surrounding air that is cooler. Thereby, the heat dissipating structure 305 regulates the temperature of the cells. In order to maximise the surface area of contact with the surrounding air, the heat dissipating structure 305 comprises airflow guides 305a. The airflow guides 305a are fin-like structures that extends from a base of the heat dissipating structure 305 to form the front surface of the heat dissipating structure 305. The airflow guides 305 may extend along the entire length of the base or may cover the base partially. On a rear surface of the heat dissipating structure 305, there are extension members that engage with the thermal shield 303 and the partition structures 301, 302 as will be seen in Fig. 7.
[00041] Figs. 6 exemplarily illustrates a plan view of the thermal barrier assembly 103 illustrated in Fig. 5 and an enlarged view of a detail of the plan view, respectively. As seen Fig. 6, the thermal shield 303 surrounding the first set of cells 104a, 104b ends in thermal contact with the heat dissipating structure 305 on its end surface. The first partition structure 301 and second partition structure 302 confirm with the first surface 501 (shown in Fig. 7) and the second surface 502 (shown in Fig 7) of the first set of cells. Consider first cell 104a of the adjacent cells to have the first partition structure wrapped around it on a first surface 501. The same first partition structure 301 that extends along the length of the row with the first set of cells 104a, 104b is wrapped on a second surface 502 of the adjacent cell 104b. Similarly, the second partition structure 302 is wrapped on the second surface 501 of the first cell 104a and wrapped on the first surface 501 of the adjacent cell 104b. At all times, there is a uniform gap in between the first surface 501 and the first partition structure 301 and second partition structure 302 or the second surface 502 and the first partition structure 301 and second partition structure 302. A liquid coolant runs therebetween within the gap. Thus, between two adjacent cells 104a, 104b, the first partition structure 301 may resemble an ‘horizontally oriented inverted-S shape’ in the plan view and the second partition structure 302 may resemble an ‘horizontally oriented S-shape’ in the plan view. The direction of wrapping the first partition structure 301 and the second partition structure 302 are opposite to each other. Also, can be seen is that the first partition structure 301 and the second partition structure 302 prevent direct contact between the cells 104a, 104b. The first partition structure 301 and the second partition structure 302 get heated with the heat from the cells 104a, 104b. To avoid communicating this heat to adjacent rows of cells, the thermal shield 303 acts as an insulation layer. On portions of the first surface 501 or the second surface 502 of the cells 104a, 104b, where the partition structure 301, 302 is absent, the thermal shield 303 is in direct thermal contact with the cells 104a, 104b preventing transfer of heat to other cells in other rows.
[00042] Fig. 7 exemplarily illustrates an exploded view of the thermal barrier assembly 103 encapsulating at least one cell 104b positioned in at least one row 305. Assume the cell 104b is positioned in a row 305 of the placeholders 106a of a cell holder 106 as described in Fig. 2. Once positioned, the first partition structure 301 is positioned in thermal contact with the first surface 501 of the cell 104b. The second partition structure 302 is positioned vertically below the first partition surface 301 and in thermal contact with the second surface 502 of the same cell 104b. On one side of the cell 104b, the first partition structure 301 covers a section of the external surface 501 and on the other side, the second partition structure 302 covers another section of the external surface 502. After the first partition structure 301 and the second partition structure 302 are in thermal contact with the cell 104b, the thermal shield 303 is positioned in thermal contact with the partition structures 301, 302 and the cell 104b. The thermal shield 303 also has a substantially serpentine profile to conform with the external surface 501, 502 of the cell 104b and the contour of the partition structures 301, 302. The heat dissipating structure 305 comprises evenly distributed flat extension members 305c extending from the base 305b to engage with the ends 301a, 302a of the partition structures 301, 302 and the thermal shield 303.
[00043] The serpentine profiled partition structures 301, 302 comprise a series of alternating crests 301c, 302c and troughs 301d, 302d, as seen. The surface of the crests 301c, 302c and troughs 301d, 302d is in thermal contact with the cells. The contour of the crests 301c, 302c and the troughs 301d, 302d conforms with the external surface 501, 502 of the cell 104b, while having a gap in between the external surface 501, 502 of the cell 104b and the crests 301c, 302c and the troughs 301d, 302d.
[00044] A liquid coolant 600 flows in between the gap and ensures good surface contact and assembly of the cells, such as, 104b into the crests 301c, 302c and the troughs 301d, 302d that conform to the surfaces 501, 502 of the cells 104b, a flat section 301e, 302e is provided between a crest 301c, 302c and a trough 301d, 302d, to mark start of the crest 301c, 302c and the trough 301d, 302d.
[00045] To keep the liquid coolant 600 in thermal contact with the cells 104b, the surface of the partition structures 301, 302 in the crests 301c, 302c and the troughs 301d, 302d has an adhesive layer or any attachment means, such as, screw and nut assembly, Velcro strips, etc., disposed on them. Such attachment means withstand elevated temperature of the cells 104b. The partition structures 301, 302 are made of a composite, for example, a graphite composite with a thermal conductivity in a range from about 700 W/mK to about 100 W/mK along its length. The partition structures 301, 302 can sustain elevated temperatures of about 400 degree Celsius. In an embodiment, the serpentine partition structures 301, 302 may be made into elastic structures that conform to the external surface 501, 502 of the cells 104b and ensure a uniform gap between the cells 104b and the partition structures 301, 302, without needing any attachment means.
[00046] The thermal shield 303 is a sheet made of an inorganic compound, such as, aluminium magnesium silicate that has a high melting point of about 1300oC to about 1900oC. The thermal shield 303 effectively functions up to about 1200oC to resist fire and due to the absence of any organic material, the thermal shield 303 is non-flammable. The thickness of the thermal shield 303 can increase if more number of cells is present in the battery module 100. As per an embodiment, the thickness of the thermal shield 303 is about 3mm to prevent fire propagation to about 3 rows of cells with minor damages to the cells, while their output voltages remain undisturbed.
[00047] The heat dissipating structures 304, 305 at the ends of the partitions structures 301, 302 and the thermal shield 303 are made of light weight materials, such as, Aluminium and are exposed to ambient air for passive cooling of the cells 104b. In this embodiment, the thermal shield 303 as a sheet is replaced by the insulation foam. The insulation foam 303 has good flame retarding ability and is light weight (<0.2g/cm3) with very low thermal conduction (0.1W/mK). The insulation foam 303 may expand on being exposed to elevated temperatures and may isolate the other cells from heat and fire. Such an insulation foam 303 also facilitates tight packaging of the cells 104 and maintains the cells 104 intact even in case of catastrophe, by providing cushioning to the cells 104 in the casing 101.
[00048] Fig. 8 exemplarily illustrate a plan view of the thermal barrier assembly 103 illustrated in Fig.3, encompassing the cells 104. The thermal barrier assembly 103 includes a circulating liquid 600 flowing through the battery module 100, in between at least two partition structures 301, 302.
[00049] The serpentine profile of the at least two partition structures 301, 302 create a channel 601, encompassing at least one row of battery cells 104a, 104b, 104c, 104d (shown in Fig. 3). The channel 601 enables the liquid coolant 600 to flow from one end, for example a first end 602, of the channel 600 to another end of the channel 600, for example a second end 603, while being in constant contact with each cell 104a, 104b, 104c, 104d of the battery module 100. As the liquid coolant flows through the channel 601, it absorbs the heat generated by the battery cells 104a, 104b, 104c, 104d and extracts the heat away from the battery module 100. This helps to prevent the battery cells 104a, 104b, 104c, 104d from overheating and reduces the risk of thermal runaway. Once the liquid coolant 600 has passed through all the battery cells 104a, 104b, 104c, 104d in the channel 601, the liquid coolant 600 exits through the outlet, herein the second end 603. The liquid coolant 600 being in thermal contact of each cell 104a, 104b, 104c, 104d of the plurality of cells 104, along a length of at least one row of the plurality of rows 306, 307 (shown in Fig. 4) enables dissipating the extracted heat away from the plurality of cells 104 in the plurality of rows 306, 307.
[00050] In an embodiment, as the liquid coolant 600, flows out of the battery module 100, through each second ends 603 of each channel 600, and moves out of the battery module 100 through an outlet 600b. While the liquid coolant 600 moves out of each channel 600, the liquid coolant is cooled down, because of being in contact with at least one heat dissipating structure 304, 305, for example a heat exchanger.
[00051] In another embodiment, as the liquid coolant 600, flows out of the thermal barrier assembly 103 through the outlet 600b, the liquid coolant 600 is further cooled down, because of being circulated through a separate cooling system (not shown).
[00052] Further, the cooled liquid coolant 600 is then circulated back into the thermal barrier assembly 103 through an inlet 600a. Post the liquid coolant 600 enters the inlet 600a, the liquid coolant 600 re-enters each of the channels 601, through the first end 602 of each of the channels 601, and the process starts all over again.
[00053] Thereby, the present invention, enables faster cooling of the battery module 100, by using both the constant circulation of the liquid coolant 600 and the dissipation of heat through the heat exchangers, such as heat dissipating structure 304, 305.
[00054] The continuous circulation of the liquid coolant 600 helps to maintain a consistent temperature within the battery module 100, which is essential for the safe and efficient operation of the overall battery system. It also ensures that the battery cells 104a, 104b, 104c, 104d are not subjected to extreme temperature fluctuations, which can cause damage and reduce their overall lifespan.
[00055] Further, the constant circulation of the liquid coolant 600 is more beneficial when compared to other forms of coolants, because liquid coolant 600 in circulation provides more effective and efficient cooling of the battery cells 104a, 104b, 104c, 104d within the battery module 100. A circulating liquid coolant 600 can extract heat from all battery cells 104a, 104b, 104c, 104d within the battery module 100, ensuring that the temperature remains consistent throughout the battery module 100. The continuous flow of liquid coolant 103 also helps to distribute heat more evenly, which reduces the risk of localized hotspots that can damage the battery cells 104a, 104b, 104c, 104d in the long run. Moreover, the use of a circulating liquid coolant 600 provides an opportunity for the cooling system to be integrated with other components such as heat exchangers and radiators, which further enhance the cooling capacity of the overall battery module 100. Further, such configuration is capable of aiding in improving the overall efficiency of the battery module 100 and reduce energy loss.
[00056] The serpentine profile of the partition structures 301, 302, due to the curved profile, ensures disruption of the flow of the circulating liquid coolant 600, thereby ensuring increased turbulence of flow. The turbulence helps to break up any boundary layers around the cells 104a, 104b, 104c, 104d, allowing the liquid coolant 600 to more efficiently absorb heat from the cells 104a, 104b, 104c, 104d. The increased turbulence also helps to improve heat transfer between the liquid coolant 600 and the cells 104a, 104b, 104c, 104d, as the turbulence creates more contact between the liquid coolant 600 and the surface of the cells 104a, 104b, 104c, 104d, which increases rate of heat transfer.
[00057] Further, the disruption of flow of liquid coolant 600 due to serpentine profile help in reducing fouling in the heat dissipating structures 304, 305. Fouling occurs when particles or other contaminants accumulate on the surface of the heat dissipating structures 304, 305, reducing its effectiveness. The increased turbulence can help to prevent these contaminants from settling on the heat dissipating structure’s 304, 305 surface, reducing the risk of fouling.
[00058] The battery module with the thermal barrier assembly disclosed in the present invention provides the following technical advancement in the field of thermal management of energy storage devices: The battery modules disclosed here are rechargeable modules, such as, Lithium-ion batteries with Lithium-ion cells. During normal operation of the battery module, the temperature of cells rises. During charging, overcharging, extended operation, the temperatures may drastically rise. In both these conditions, the thermal barrier assembly its associated components, such as the partitions structures, the thermal shield, and the heat dissipating structures extract and dissipate the heat away from the cells. In case of overcharging or abuse to the battery module, where a fire has ensued in the battery module, the thermal shield is capable of arresting propagation of fire further to other cells in the battery module. The insulating nature of the thermal shield ensures that the partition structures along with the liquid fluid extracts the heat and transmit it towards the heat dissipating, instead of spreading to other cells in other rows. Thus, the thermal shield channelizes the flow of heat towards the heat dissipating structure and away from the cells.
[00059] Improvements and modifications may be incorporated herein without deviating from the scope of the invention.
LIST OF REFERENCE NUMERALS

100- Battery module
101- casing
102- first end cover
103- thermal barrier assembly
104-cells
104a, 104b- first plurality cells
104c, 104d, second plurality of cells,
105, 106-cell holders
107- second end cover
108, 109-protective sheets
301- first partition structure
302-second partition structure
301a, 302a, 301b, 302b- ends of the partition structures
301c, 302c- crests in partition structures
301d, 302d-troughs in partition structures
301e, 302e-flat section between crests and troughs in the partition structures
303-thermal shield
303a, 303b- ends of thermal shield.
304, 305-heat dissipating structures
304a-airflow guides
306- first row
307- second row
401-cell pack
501- first surface
502-second surface
600- liquid coolant
600a- inlet
600b- outlet
601- channel
602- first end
603- second end

, Claims:I/We claim:
1. A battery module (100) comprising:
a plurality of cells (104), said plurality of cells (104) being positioned in a plurality of rows (306, 307); and
a thermal barrier assembly (103), said thermal barrier assembly (103) being configured to encapsulate said plurality of cells (104) in said plurality of rows (306, 307) for thermal management of said plurality of cells (104), wherein said thermal barrier assembly (103) comprises:
at least two partition structures (301, 302) having a serpentine profile with a contour conforming to the surfaces of the adjacent cells (104),
wherein said at least two partition structures (301, 302) being configured to form a channel (601), encompassing at least one row of said plurality of rows (306, 307),
wherein said channel (601) enables circulation of a liquid coolant (600) from a first end (602) of said channel (601) to a second end (603) of said channel (601), wherein
said liquid coolant (600) being in thermal contact of each cell (104a, 104b, 104c, 104d) of said plurality of cells (104), along a length of at least one row of said plurality of rows (306, 307) for dissipating the extracted heat away from said plurality of cells (104) in said plurality of rows (306, 307).
2. The battery module (100) of claim 1, wherein said at least one of said at least two partition structures (301, 302) being a zig-zag shaped structure.
3. The battery module (100) of claim 1, wherein said liquid coolant (600), being in contact with one of an at least one heat dissipating structure (304, 305) and a radiator, after flowing out of said second end (603) of said battery module (100).
4. The battery module (100) of claim 1, wherein said liquid coolant (600), being in contact with a separate cooling system, after flowing out of said battery module (100).
5. The battery module (100) of claim 1, wherein said at least one partition structure (301, 302) comprises a first partition structure (301), and a second partition structure (302).
6. The battery module (100) of claim 1, wherein said at least one cell being a first plurality of cells (104a, 104b) positioned in one of said plurality of rows (306, 307).
7. The battery module (100) of claim 5, wherein each of said second partition structure (302) and said first partition structure (301) having a serpentine profile with a contour conforming with a first surface (501) and a second surface (502) of adjacent cells (104a, 104b).
8. The battery module (100) of claim 1, wherein said liquid coolant (600) flows in between a gap present between each of said second partition structure (302) and said first partition structure (301) and a first surface (501) and a second surface (502) of said cells (104a, 104b, 104c, 104d).
9. The battery module of (100) claim 5, where each of said first partition structure (301) and said second partition structure (302) comprising a series of alternating crests (301c, 302c) and troughs (301d, 302d) for establishing a thermal contact with a liquid coolant (600) flowing in between said cells (104a, 104b, 104c, 104d) and at least two partition structures (301, 302).
10. The battery module (100) of claim 8, wherein said first surface (501) and said second surface (502) of said at least one cell (104a) being diametrically opposite and together substantially define an external periphery of said at least one cell (104a).
11. The battery module (100) of claim 5, wherein said first partition structure (301) and said second partition structure (302) being made of a composite with a thermal conductivity in a range from about 700 W/mK to about 100 W/mK along its length.
12. The battery module (100) of claim 1, wherein said thermal barrier assembly (103) comprising at least one thermal shield (303) with a substantially serpentine profile in contact with said at least one partition structure (301, 302) and extending along the length of said at least one row (306, 307) for thermally insulating said at least one cell (104a) in said at least one row (306, 307) from said plurality of cells (104) in said plurality of rows (306, 307).
13. The battery module (100) of claim 12, wherein said at least one thermal shield (303) being positioned between a first plurality of cells (104a, 104b) and a second plurality of cells (104c, 104d) in contact with said at least one partition structure (301, 302) of each of said first plurality of cells (104a, 104b) and said second plurality of cells (104c, 104d), and said each of the first plurality of cells (104a, 104b) and said second plurality of cells (104c, 104d) for arresting propagation of one of the heat and fire from said first plurality of cells (104a, 104b) towards said second plurality of cells (104c, 104d).
14. The battery module (100) of claim 12, wherein said at least one thermal shield (303) separates a series connected cell pack (401) from one of adjacent cells and adjacent cell packs.
15. The battery module (100) of claim 12, wherein said at least one thermal shield (303) being thermal conducting on one side and thermal insulating on an opposite side.