Description:TECHNICAL FIELD
[0001] The present subject matter relates, in general, to electric vehicles (EVs) and, particularly, to gas deflectors for evacuating gases released from battery packs of the EVs during a thermal runaway event.
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BACKGROUND
[0002] Electric vehicles are powered by battery packs comprising multiple battery cells and modules arranged in series and parallel configurations. A battery cell is the fundamental unit of energy storage, and its thermal and electrical characteristics influence the overall performance 10 and safety of the battery pack. Modules are formed by grouping multiple cells and enclosing them within a mechanical structure to provide physical protection and electrical connectivity.
[0003] During normal operation, battery cells generate heat due to charging, discharging, and power delivery. Under certain conditions, 15 excessive heat generation and internal short circuit of cells may occur, leading to a thermal runaway event. Thermal runaway is a condition in which the heat generated within a cell exceeds the rate at which it can be dissipated, potentially causing the cell to fail and triggering a chain reaction across adjacent cells. This sequential failure is referred to as thermal 20 propagation.
[0004] Regulatory requirements AUTOMOTIVE INDUSTRY STANDARD (AIS) 156 (Amendment 2) mandate that the Rechargeable Electrical Energy Storage System (REESS) should withstand thermal propagation which is triggered by an internal short circuit, leading to a single 25 cell thermal runaway and subsequent thermal propagation and shall not result in fire and explosion to ensure vehicle safety and occupant protection.
[0005] Effective management of high-temperature gases and flames generated during thermal runaway is essential to prevent damage to vehicle components and to maintain the structural integrity of the battery pack. The 30
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gases must be safely evacuated from the battery enclosure to avoid pressure buildup and minimize the risk of fire or explosion.
SUMMARY OF THE INVENTION
[0006] This summary is provided to introduce a selection of concepts in 5 a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
[0007] In an embodiment of the present invention, the electric vehicle 10 (EV) comprises a frame having at least one cross member mounted on the left-hand side (LH) of the frame and at least one cross member mounted on the right-hand side (RH) of the frame to form an enclosure. A battery pack is supported within the enclosure such that a LH cross member aligns with the first sidewall of a housing of the battery pack and a RH cross member 15 aligns with a second sidewall opposite to the first sidewall of a housing, and at least one sidewall connecting the first sidewall and the second sidewall is located at a front of the enclosure. At least one gas vent is provided on a surface of the housing of the battery pack to expel gases produced within the battery pack during a thermal runaway event. At least one gas deflector 20 having a hollow tubular body with a first end and a second end is provided. The at least one gas deflector is provided as a flame quenching vent path. The first end of the hollow tubular body is connected to the at least one gas vent, whereas the second end of the hollow tubular body is oriented towards the front of the enclosure. 25
[0008] The gas deflector is configured to serve not only as a mechanism to channelize the gasses in a safe manner but also as a means to quench any fire that may ensue owing to the runaway event. In an embodiment of the present invention, the gas deflector includes a perforated cylindrical tube positioned within the hollow tubular body, a layer of insulating wool 30 surrounding the perforated cylinder, and an exhaust cap provided at the 3
second end of the hollow tubular body. In one example, the gas deflector may be connected to the gas vent by engaging an external male threads formed on the first end of the hollow tubular body to an internal female threads formed on the surface of the housing. In another example, the gas deflector may be connected to the gas vent through at least one of gluing 5 and snap fitting the first end of the hollow tubular body to the surface of the housing.
[0009] The foregoing general description of the illustrative embodiments and the following detailed description thereof are merely exemplary aspects of the teachings of this disclosure and are not restrictive. 10
BRIEF DESCRIPTION OF DRAWINGS
[0010] The present subject matter is now described, in accordance with examples and with reference to the accompanying figures, in which:
[0011] Fig. 1 illustrates a side view of an electric vehicle (EV), in 15 accordance with an implementation of the present subject matter;
[0012] Fig. 2 illustrates an enlarged view of a battery pack mounted on the EV, in accordance with an implementation of the present subject matter;
[0013] Fig. 3A illustrates an orientation of a gas deflector on a housing of the battery pack, in accordance with an implementation of the present 20 subject matter;
[0014] Fig. 3B illustrates a sectional view of the battery pack, in accordance with an implementation of the present subject matter;
[0015] Fig. 3C illustrates a front view of the battery pack, in accordance with an implementation of the present subject matter; 25
[0016] Fig. 3D illustrates a perspective view of the battery pack, in accordance with an implementation of the present subject matter;
[0017] Fig. 3E illustrates another perspective view of the battery pack, in accordance with an implementation of the present subject matter;
[0018] Fig. 4 illustrates an enlarged view of the battery pack, in 30 accordance with another implementation of the present subject matter; 4
[0019] Fig. 5A illustrates another orientation of the gas deflector on the housing of the battery pack, in accordance with an implementation of the present subject matter;
[0020] Fig. 5B illustrates a cross-sectional view of the battery pack, in accordance with an implementation of the present subject matter; 5
[0021] Fig. 6A illustrates a side view of the gas deflector, in accordance with an implementation of the present subject matter;
[0022] Fig. 6B illustrates another side view of the gas deflector, in accordance with an implementation of the present subject matter;
[0023] Fig. 7A illustrates a perspective view of a hollow tubular body of 10 the gas deflector, in accordance with an implementation of the present subject matter;
[0024] Fig. 7B illustrates a perspective view of a perforated cylindrical tube of the gas deflector, in accordance with an implementation of the present subject matter; 15
[0025] Fig. 7C illustrates a perspective view of an insulating wool layer of the gas deflector, in accordance with an implementation of the present subject matter;
[0026] Fig. 7D illustrates a perspective view of an assembly depicting an encapsulation of the insulating wool over the perforated cylindrical tube, 20 in accordance with an implementation of the present subject matter;
[0027] Fig. 8A illustrates a perspective view of a first end of the hollow tubular body, in accordance with an implementation of the present subject matter;
[0028] Fig. 8B illustrates a bottom view of the first end of the hollow 25 tubular body, in accordance with an implementation of the present subject matter;
[0029] Fig. 8C illustrates a top view of the first end of the hollow tubular body, in accordance with an implementation of the present subject matter; 5
[0030] Fig. 9A illustrates a perspective view of a first end cap of the gas deflector, in accordance with an implementation of the present subject matter;
[0031] Fig. 9B illustrates a bottom view of the first end cap of the gas deflector, in accordance with an implementation of the present subject 5 matter;
[0032] Fig. 9C illustrates a top view of the first end cap of the gas deflector, in accordance with an implementation of the present subject matter;
[0033] Fig. 10A illustrates a perspective view of a second end cap of the 10 gas deflector, in accordance with an implementation of the present subject matter;
[0034] Fig. 10B illustrates a top view of the second end cap of the gas deflector, in accordance with an implementation of the present subject matter; 15
[0035] Fig. 10C illustrates a bottom view of the second end cap of the gas deflector, in accordance with an implementation of the present subject matter;
DESCRIPTION OF EMBODIMENTS 20
[0036] The present subject matter relates to a gas deflector for evacuating the gases released from a battery pack of the EV during a thermal runaway event.
[0037] In an event of a thermal runaway, a battery cell, such as a lithium-ion cell generates heat at a rate several times higher than the rate at which 25 the heat can be dissipated. The thermal runaway of the battery cell may cause thermal propagation in a battery module in which the battery cell is located and may cause thermal runaway to occur in one or more of the remaining cells within the battery module. The thermal propagation caused due to the continuous thermal runaway within the battery module may 30 further lead to fire and explosion in the battery module. 6
[0038] Batteries, such as Lithium-ion batteries, have various uses due to their utility and advantages over other types of batteries. In an example, Lithium-ion batteries may be used in the Electric Vehicles (EVs). As the demand for batteries for EVs is increasing, there is also a growing need to make the EVs safer. An event such as the thermal propagation can be 5 severely detrimental to the safety of a user of the electric vehicle. The battery modules used in the EVs are susceptible to thermal runaway, during which a malfunctioning cell emits high-temperature, high-pressure gases and flames.
[0039] In existing EV designs, the battery pack is mounted within a 10 compact frame structure, often surrounded by plastic body panels and other sensitive components. During the thermal runaway event, gases expelled from the battery pack may come into direct contact with these components, leading to melting, deformation, or ignition of plastic parts. The absence of a dedicated mechanism to isolate and redirect these gases increases the 15 risk of fire and structural damage to the vehicle.
[0040] The expelled gases during thermal runaway are typically released through vents provided on a housing of the battery pack. In the absence of a controlled evacuation path, these gases may accumulate within the housing of the battery pack, causing pressure buildup and 20 increasing the likelihood of explosion inside the battery pack. Additionally, the uncontrolled release of flames and hot gases from the battery pack not only compromises the structural integrity of the vehicle but also poses a significant safety risk to the rider. Exposure to flames or high-pressure gases during vehicle operation may cause physical injury to the rider and 25 may violate safety standards and regulations governing electric vehicle battery systems.
[0041] However, the vents provided on the housing of the existing battery pack lack structural integration for the controlled release of flames and hot gases away from the battery pack. The absence of a dedicated 30 structure for the controlled release of flames and hot gases away from the 7
battery pack creates a potential safety hazard within the vehicle architecture. Particularly, the hot gases expelled from the battery pack typically contain hydrogen, carbon monoxide, hydrogen fluoride, and various hydrocarbon compounds that form explosive mixture when combined with atmospheric oxygen under certain concentration and 5 temperature conditions. Further, the flames expelled from the battery back may ignite secondary fires within the vehicle structure which in turn may burn or injure the rider.
[0042] The present subject matter is related to gas deflectors that provide to address the above-described shortcomings relating to battery 10 packs in electric vehicles (EV).
[0043] In accordance with example embodiments of the present subject matter, the electric vehicle comprises a frame that has at least one cross member mounted on the left-hand side (LH) of the frame and at least one cross member mounted on the right-hand side (RH) of the frame to form an 15 enclosure. A battery pack of the EV is supported within the enclosure such that a LH cross member aligns with a first sidewall of a housing of the battery pack, a RH cross member aligns with a second sidewall opposite of the first sidewall of the housing, and at least one sidewall connecting the first sidewall and the second sidewall is located at a front of the enclosure. At 20 least one gas vent is provided on a surface of the housing of the battery pack to expel gases produced within the battery pack during a thermal runaway event. Furthermore, the electric vehicle comprises at least one gas deflector. The at least one gas deflector is provided as a flame quenching vent path. The at least one gas deflector has a hollow tubular body with a 25 first end and a second end. The first end of the hollow tubular body is connected to the at least one gas vent. The second end of the hollow tubular body is oriented towards the front of the enclosure.
[0044] The claimed subject matter addresses the above-described technical problems by providing a design that efficient redirects expelled 30 gases away from the housing of the battery pack and channelize the same 8
towards the front of the EV, thereby minimizing the safety risk to the rider. Further, the external positioning of the gas deflector outside the housing of the battery pack eliminates the need for internal flame suppression components, thereby eliminating the design complexity and providing compact packing of the cells within the battery pack for higher energy 5 storage. Furthermore, the external placement of the gas deflector allows easy and cost-effective maintenance of the battery pack.
[0045] The above and other features, aspects, and advantages of the subject matter will be better explained with regard to the following description and accompanying figures. It should be noted that the 10 description and figures merely illustrate the principles of the present subject matter along with examples described herein and should not be construed as a limitation to the present subject matter. It is thus understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, 15 all statements herein reciting principles, aspects, and examples thereof, are intended to encompass equivalents thereof. Further, for the sake of simplicity, and without limitation, the same numbers are used throughout the drawings to reference like features and components.
[0046] Fig. 1 illustrates a side view of an electric vehicle (EV) 100, in 20 accordance with an implementation of the present subject matter.
[0047] As shown in Fig. 1, the electric vehicle 100 comprises a frame 102 that extends longitudinally along a length of the electric vehicle 100 from a headlight to a seat of the vehicle 100. At least one cross member is mounted on the left-hand side (LH) of the frame 102 and at least one cross 25 member is mounted on the right-hand side (RH) of the frame 102. The LH and RH of the frame 102 are spaced apart from one another. The arrangement of the at least one cross members mounted on the LH and RH of the frame 102 forms an enclosure 138 to support a battery pack 106 of the EV. 30
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[0048] The LH cross member 104 and RH cross member may be fixedly secured to the frame 102 through welding, bolting, riveting, or any other mechanical fasteners. The enclosure 138 formed by at least one cross member may provide a structural support to the battery pack 106, thereby reducing the risk of displacement or damage to the battery pack 106 under 5 harsh driving conditions.
[0049] In an embodiment, the battery pack 106 includes a housing 108 having a first sidewall 110a, a second sidewall (shown in Fig. 3C) opposite the first sidewall 110a, and at least one sidewall 140a connecting the first sidewall 110a and the second sidewall 110. When the battery pack is 10 positioned within the enclosure 138, a LH cross member 104 aligns with the first sidewall 110a of the housing 108. Similarly, a RH cross member (not shown in Fig. 1) aligns with the second sidewall 110b of the housing 108 which is opposite to the first sidewall 110a. At least one sidewall 140a connecting the first sidewall 110a and the second sidewall 110b is located 15 at a front 140 of the enclosure 138, while other sidewalls are located along the top and bottom of the enclosure.
[0050] As will be apparent to one skilled in the art, the housing 108 of the battery pack 106 is a box-like structure. As will be understood, the shape of the housing 108 of the battery pack 106 may not be an exact geometrical 20 shape and may rather be configured to be compatible with the frame 102 of the EV which is in turn governed by the design of the EV. Nevertheless, in accordance with example embodiments of the present subject matter, the shape of the housing 108 resembles a box-like structure, shaped substantially like a rectangular prism or an oblong box that has six external 25 surfaces, herein referred to as sidewalls of the housing 108. A pair of opposing sidewalls along the length of the housing 108 is supported by the cross members of the frame 102 on either side of the frame 102 such that at least one sidewall is positioned towards the front of the frame 102 of the EV, as depicted. A sidewall opposing the sidewall positioned towards the 30 front of the frame 102 may be located substantially proximal to a seat of the 10
EV. Likewise, another pair of opposing sidewalls may be located towards the top and bottom of the enclosure 138 of the battery pack 106.
[0051] In one embodiment, at least one gas vent 112 (shown in later figures) is provided on a surface of the housing 108 of the battery pack 106. The at least one gas vent 112 serves to expel gases produced within the 5 battery pack 106 whenever a thermal runaway event occurs in the battery pack 106 (described later).
[0052] Fig. 2 illustrates an enlarged view of the battery pack 106 mounted on the EV, in accordance with an implementation of the present subject matter. 10
[0053] As shown in Fig. 2, the at least one gas vent 112 may be provided on the first sidewall 110a of the housing 108 of the battery pack 106. Similar to the first sidewall 110a, the at least one gas vent 112 may also be provided on the second sidewall 110b (not shown in Fig. 2) of the housing 108 of the battery pack 106. 15
[0054] In an embodiment, the least one gas vent 112 provided on the first sidewall 110a and the second sidewall 110b of the housing 108 may be connected to the at least one gas deflector 114. The at least one gas deflector 114 redirects gases expelled from the at least one gas vent 112 towards the front 140 of the enclosure 138. 20
[0055] The gas deflectors 114 ensure controlled redirection of the gases expelled from the gas vent 112 towards the front 140 of the enclosure 138, thereby ensuring that the expelled gases are away from the battery pack 106 which in turn minimizes the safety risk to the rider. The gas deflectors 114 are configured to prevent the expelled gases from contacting any body 25 panels of the electric vehicle 100 by redirecting the gases towards the front end and downward underneath the vehicle 100. This helps in preventing damage to the plastic components of the vehicle 100 and reduces the risk of injury to the rider. Further, the external positioning of the gas deflector 114 outside the housing 108 of the battery pack 106 eliminates the need for 30 internal flame suppression components, thereby eliminating the design 11
complexity and providing compact packing of the cells within the battery pack 106 for higher energy storage.
[0056] Fig. 3A illustrates an orientation of the gas deflector 114 on the housing 108 of the battery pack 106, in accordance with an implementation of the present subject matter. Fig. 3B illustrates a sectional view of the 5 battery pack 106 as depicted in Fig 3A, in accordance with an implementation of the present subject matter.
[0057] The battery pack 106 configurations in the electric vehicle 100 may vary significantly based on the orientation of the cell vents within the modules. Each module within the battery pack 106 may contain a plurality 10 of cells that may be configured with either top-facing or bottom-facing vents. The gas deflector 114 may be strategically connected to the surface of the housing 108 of the battery pack 106 based on the orientation of the cell vents within the modules.
[0058] In an embodiment, the deflectors 114 may be connected to the 15 first sidewall 110a and the second sidewall 110b of the housing 108. As shown in Fig. 3A, at least one deflector 114 may be connected to a gas vent 112 provided on the housing 108 of the battery pack 106 along a direction facing towards the front in a downward direction of the EV, as depicted by cross-sectional line A-A. 20
[0059] Fig. 3B shows cross-sectional view of the battery pack along the cross-sectional line A-A.
[0060] As is known, embodiments where the cells in the modules of the battery pack have vents that face in opposite direction, the battery pack 106 may incorporate a separate venting channel corresponding to the direction 25 of the vents.
[0061] As shown in Fig. 3B, a plurality of modules 122 may be arranged within the battery pack 106 such that vents 116 of the cells of the modules 122 may face in opposite directions. In one example embodiment, the vent 116 of the cell of one module 122 may face towards the sidewall aligned 30 along RH side of the frame, while the vent 116 of the cell of adjacent module 12
122 may face towards the sidewall aligned along LH side of the frame. Due to this opposite orientation of the vents 116 within the battery back 106, in the thermal runaway event, gases emitted from each module 122 are directed into their respective channels provided along the side that the vents face. 5
[0062] A first venting channel 120a may be positioned directly above the module 122 with a top-vented cells 116. Similarly, a second venting channel 120b may be positioned beneath the module 122, also with top-vented cells 116. The top-vented cells 116 are oriented such that the vents are away from each other. The first venting channel 120a and the second venting 10 channel 120b are isolated from each other so that gases emitted from the top-vented cells 116 exit the battery housing through their respective venting channels.
[0063] In one embodiment, the first venting channel 120a and the second venting channel 120b may be connected to a dedicated gas vent 15 114 provided on the housing 108 of the battery pack 106. In one example embodiment, the first venting channel 120a may be connected to the gas vent 114 provided on the first sidewall 110a of the housing 108, whereas the second venting channel 120b may be connected to the gas vent 114 provided on the second sidewall 110b of the housing 108. 20
[0064] In another embodiment, the gas deflector 114 may be connected to each of the gas vent 114 provided on the first sidewall 110a and the second sidewall 110b of the housing 108. In one example embodiment, the gas deflector 114 connected to each of the gas vent 112 provided on the first sidewall 110a and the second sidewall 110b of the housing 108 may be 25 oriented towards the front 140 of the enclosure 138, thereby routing the gases expelled from the module 122 away from the battery pack and the rider which in turn ensures the safety of the vehicle as well as the rider. In such embodiments, as will be elaborated later, the gas deflectors 114 have a L-shaped configuration to direct the gases coming through the gas vents 30
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on the sidewalls that are aligned along the cross members of the frame to the front of the EV.
[0065] Fig. 3C illustrates a front view of the battery pack 106, in accordance with an implementation of the present subject matter. In accordance with the example embodiment depicted in figure 3C, a pair of 5 gas deflectors 114 is provided on each of the RH and LH sidewalls of the housing of the battery pack 106 that aligns with the cross members of the frame of the EV. The figure also depicts how the gas deflectors 114 have a curved body to direct the expelled gases towards the front 104 of the frame 102 of the EV. 10
[0066] Fig. 3D and 3E each illustrate a perspective view of the battery pack 106, in accordance with an implementation of the present subject matter. As shown, the orientation of the deflector 114 is such that its exit terminal is away from the housing 106 and towards the front sidewall 104a of the housing. 15
[0067] Fig. 4 illustrates an enlarged view of the battery pack 106, in accordance with another implementation of the present subject matter.
[0068] As shown in Fig. 4, the at least one gas vent 112 may be provided on the sidewall 140a that is located at the front 140 of the enclosure 138 and connects the first sidewall 110a and the second sidewall 110b. 20
[0069] In an embodiment, the least one gas vent 112 provided on the sidewall 140a may be connected to the at least one gas deflector 114. The at least one gas deflector 114 redirects gases expelled from the at least one gas vent 112 towards the front 140 of the EV. The gas deflector 114 ensures controlled redirection of the gases expelled from the gas vent 112 towards 25 the front 140 of the frame 102, thereby ensuring that the expelled gases are away from the battery pack 106 which in turn minimizes the safety risk to the rider. Furthermore, the external placement of the gas deflector 114 allows easy and cost-effective maintenance of the battery pack 106.
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[0070] Fig. 5A illustrates another orientation of the gas deflector 114 on the housing 108 of the battery pack 106, in accordance with an implementation of the present subject matter.
[0071] As shown in Fig. 5A, the deflector 114 may be connected to a gas vent 112 provided on the housing 108 on the sidewall 140a located at 5 the front 140 of the enclosure 138. The orientation of the deflector 114 towards the front of the EV allows the deflector 114 to redirect the gases away from the battery pack 106, thereby eliminating the chances of fire within the battery pack 106 due to expelled gases. Fig. 5B shows cross-sectional view of the battery pack 106 along the cross-sectional line B-B 10 depicted in Fig. 5A.
[0072] As shown in Fig. 5B, a plurality of modules 122 may be arranged within the battery pack 106 such that vents 116 of the cells of the modules 122 may face each other along a venting channel 118 common to the plurality of modules 122. The cells may be top vented or bottom vented. 15
[0073] In one embodiment, the common venting channel 118 may be coupled to the at least one gas vent 114 provided on the housing 108. In one example embodiment, the common venting channel 118 may be coupled to the at least one gas vent 114 provided on the sidewall 140a of the housing 108 located at the front 140 of the enclosure 138. The common 20 venting channel 118 simplifies the manufacturing of the battery pack 106, thereby reducing the cost and the size of the battery pack 106.
[0074] In embodiments where the battery pack 106 has the common venting cannel 118 located at the center of the housing 108 of the battery pack 106, at least one gas vent 112 may be provided at the center of the 25 sidewall 140a located the front 140 of the frame and at least one gas deflector 114 may be connected to the at least one gas vent 112 provided on the at least one sidewall 140a. The gas deflector 114 connected to the at least one sidewall 140a redirects the expelled gases away from the battery pack 106, thereby minimizing the safety risk to the rider. 30
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[0075] Fig. 6A illustrates a side view of the gas deflector 114, in accordance with an implementation of the present subject matter. Fig. 6B illustrates an side view of the gas deflector 114, in accordance with another implementation of the present subject matter. For the sake of ease of explanation, Figs. 6A-6B are explained together. 5
[0076] In one embodiment, the gas deflector 114 includes a hollow tubular body (shown in later Figures). In another embodiment, the gas deflector 114 may also include a perforated cylindrical tube (shown in later Figures), a layer of an insulating wool (shown in later Figures), and an exhaust cap 132. 10
[0077] As discussed above, the gas deflector 114 redirects the expelled gases from the module 122 away from the battery pack 106, thereby eliminating the chances of burn or injury to the rider.
[0078] As shown in Fig. 6A, the gas deflector 114 may have a L-shaped body. The gas deflector 114 having the L-shaped body may be used in the 15 battery pack 106 in which the vents 116 of cells within the module 122 are oriented in the opposite direction and the venting channels are separate. The L-shaped body of the gas deflector 114 not only allows the gas deflector 114 to have an efficient connection with the gas vent 112 provided on the first sidewall 110a and the second sidewall 110b of the housing 108 of the 20 battery pack 106 but also allows the gas deflector 114 to redirect the gases away from the battery pack 106 in a controlled manner.
[0079] As shown in Fig. 6B, the gas deflector 114 may have a straight body. The gas deflector 114 having the straight body may be used in the battery pack 106 in which the vents 116 of cells within the module 122 are 25 oriented in the same direction and share a common venting channel. The straight body of the gas deflector 114 not only allows the gas deflector 114 to have a simple connection with the gas vent 112 provided on the at least one sidewall 140a located at the front 140 of the housing 108 of the battery pack 106 but also allows the gas deflector 114 to redirect the gases away 30 from the battery pack 106 in a controlled manner. 16
[0080] Fig. 7A illustrates a perspective view of a hollow tubular body 124 of the gas deflector 114, in accordance with an implementation of the present subject matter.
[0081] As discussed above, the gas deflector 114 includes the hollow tubular body 124. In an example, the hollow tubular body 124 may be made 5 up of at least one of aluminum, stainless steel, brass and high-grade plastic or combination thereof.
[0082] The hollow tubular body 124 has a first end 124a and a second end 124b. In one embodiment, the first end 124a of the hollow tubular body 124 is connected to the at least one gas vent 112 and the second end 124b 10 of the hollow tubular body 124 is oriented towards the front 140 of the enclosure 138. The hollow tubular body 124 of the gas deflector 124 provides a structural framework for routing gases away from the battery pack 106 during the thermal runaway event.
[0083] In one embodiment, an external male threads may be formed on 15 the first end 124a of the hollow tubular body 124. Similarly, an internal female threads may be formed on the surface of the housing 108. In one example embodiment, the first end 124a of the hollow tubular body 124 may be connected to the at least one gas vent 112 provided on the housing 108 by engaging the external male thread formed on the first end 124a of the 20 hollow tubular body 124 to the internal female threads formed on the surface of the housing 108. The male-female connection between the first end 124a of the hollow tubular body 124 and the surface of the housing 108 provides a rigid connection of the gas deflector 114 to the housing 108 of the battery pack 106. 25
[0084] In another embodiment, the first end 124a of the hollow tubular body 124 may be connected to at least one gas vent 112 provided on the surface of the housing 108 through at least one gluing or snap fitting the first end 124a of the hollow tubular body 124 with the surface of the housing 108. The snap fitting or gluing allows simple and cost effecting connection 30
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between the gas deflector 114 and the surface of the housing 108 of the battery pack 106.
[0085] In one embodiment, the at least one gas vent 112 provided on the first sidewall 110a and the second sidewall 110b may be connected to the first end 124a of the hollow tubular body 124. In one example 5 embodiment, the hollow tubular body 124 connected to the at least one gas vent 112 provided on the first sidewall 110a and the second sidewall 110b of the housing 108 may be L-shaped.
[0086] In another embodiment, the at least one gas vent 112 provided on the at least one sidewall 140a located at the front 140 of the enclosure 10 138 may be connected to the first end 124a of the hollow tubular body 124. In one example embodiment, the hollow tubular body 124 connected to the at least one sidewall 140a may have a straight configuration.
[0087] The second end 124b of the hollow in either of the configurations of the tubular body 124 mentioned above may provide for attachment of an 15 exhaust cap 132 (elaborated later). In one example embodiment, the exhaust cap 132 may be attached to the second end 124b of the hollow tubular body 124 through threading, snap fitting, or gluing the second end 124b of the hollow tubular body 124 to the exhaust cap 132.
[0088] In one embodiment, the exhaust cap 132 may include at least 20 one of a first end cap 134 and a second end cap 136. The exhaust cap may provide controlled direction and dispersion of gases or flame expelled from the plurality of modules 122 during the thermal runaway event, thereby avoiding the contact of expelled gases or flame with the battery pack 106 and the rider. 25
[0089] Fig. 7B illustrates a perspective view of a perforated cylindrical tube 128 of the gas deflector 114, in accordance with an implementation of the present subject matter;
[0090] As discussed above, the gas deflector 114 may include the perforated cylindrical tube 128that is fitted within the hollow tubular body 30 124. In an example, the perforated cylindrical tube 128 may be made up of 18
at least one of aluminum, stainless steel, brass, and high-grade plastic or a combination thereof
[0091] In an embodiment, the perforated cylindrical tube 128 may include a first end 128a and an opposite second end 128b, each formed with a contoured profile, and a middle section 128c extending 5 therebetween. The contoured profile formed at the first end 128a and the second end 128b of the perforated cylindrical tube 128 may have a circular configuration and may have a larger diameter as compared to the middle section 128c.
[0092] In one embodiment, the contoured profiled formed on the second 10 end 128b of the perforated cylindrical tube 128 may include a female threads on an outer surface of the second end 128b and a male threads on an inner surface of the second end 128b of the perforated cylindrical tube 128. In one example embodiment, the perforated cylindrical tube may be fitted to the second end 124b of the hollow tubular body by engaging the 15 female thread formed on the outer surface of the second end 128b of the perforated cylindrical tube 128 with a male thread formed on an inner surface of the second end 124b of the hollow cylindrical body.
[0093] In embodiments, where the gas deflector 114 is in straight configuration, the first end 128a of the perforated cylindrical tube 128 may 20 correspond to the first end 124a of the hollow tubular body 124, whereas the first end 128b of the perforated cylindrical tube 128 may correspond to the first end 124b of the hollow tubular body 124
[0094] In embodiments where the gas deflector 114 is L-shaped, the perforated cylindrical tube 128 may be accommodated in the hollow tubular 25 body 124 along a length of the longer side of the L shaped gas deflector 114.
[0095] In one embodiment, the perforated cylindrical tube 128 may facilitate controlled expansion of the expelled gases within the hollow tubular body 124 of the gas deflector 114 due to a plurality of perforation 30
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128d formed on the middle section 128c of the perforated cylindrical tube 128, thereby reducing the temperature of the expelled gases.
[0096] Fig. 7C illustrates a perspective view of an insulating wool layer 130 of the gas deflector 114, in accordance with an implementation of the present subject matter. 5
[0097] As discussed above, the gas deflector 114 may include the insulating wool layer 130. In one example embodiment, the layer of the insulating wool 130 may be placed over the middle section 128c of the perforated cylindrical tube 128.The insulating wool 130 may absorb thermal energy from the expelled gases or flames passing through the plurality of 10 perforation 128d formed on the middle section 128c of the perforated cylindrical tube 128, thereby reducing their temperature below combustion thresholds which in turn quenches the flames. The insulating wool 130 may also capture liquid electrolyte droplets and solid particles that may be present in the expelled gases, thereby minimizing the pollution and the risk 15 of fire.
[0098] Fig. 7D illustrates a perspective view of an assembly 126 depicting an encapsulation of the insulating wool 130 over the perforated cylindrical tube 128, in accordance with an implementation of the present subject matter. 20
[0099] As shown in Fig. 7D, the perforated cylindrical tube 128 may be encapsulated by the layer of the insulating wool 130. In one embodiment, the layer of the insulating wool 130 may be disposed over the middle section 128c of the perforated cylindrical tube 128 along a length of the middle section 128c between the first end 128a and the second end 128b of the 25 perforated cylindrical tube 128. This arrangement of the layer of insulating wool 130 over the perforated cylindrical tube 128 ensures that each perforation 128d formed on the middle section 128c of the perforated cylindrical tube 128 are covered by the layer of the insulating wool 130, thereby efficient quenching the flames coming out from the plurality of 30 perforation 128d formed on the cylindrical perforated tube 128. 20
[00100] In one example embodiment, the encapsulation of the perforated cylindrical tube 130 by the layer of insulating wool 130 may filter the expelled gases in multiple stages. Particularly, the expelled gases flowing into the gas deflector 114 through the first end 124a of the hollow tubular body 124 may pass through the perforated cylindrical tube 128 which may expand the 5 gases in a controlled way through the plurality of perforation 128d formed on the middle section 128c of the perforated cylindrical tube 128. Once the expelled gases are passed through the plurality of perforation 128d, the expelled gases may contact a layer of the insulating wool 130. The insulating wool 130 may absorb the flames and other combustible particles, 10 such as liquid electrolyte droplets and solid particles, from the expelled gases, while the clean gases continue to pass through the insulating wool 130 towards the second end 124b of the hollow tubular body 124. The multistage processing of the expelled gases may provide effective flame suppression by efficiently absorbing the flames and other combustible 15 particles.
[00101] Fig. 8A illustrates a perspective view of a first end 124a of the hollow tubular body 124, in accordance with an implementation of the present subject matter. Fig. 8B illustrates a bottom view of the first end 124a of the hollow tubular body 124, in accordance with an implementation of the 20 present subject matter. Fig. 8C illustrates a top view of the first end 124a of the hollow tubular body 124, in accordance with an implementation of the present subject matter. For the sake of ease of explanation, Figs. 8A-8C are explained together.
[00102] As discussed above, the first end 124a of the hollow tubular body 25 124 may be connected to the at least one vent 112 through the external male thread or other mounting techniques, such as snap fitting and gluing.
[00103] As shown in Fig. 8A-8C, the external male threads may be provided on the first end 124a of the hollow tubular body 124. In one embodiment, the external male threads may be formed on the first end 124a 30 of the hollow tubular body 124 by at least one of machining, rolling, and 21
molding processed. In one example embodiment, a coating may be applied to the external male threads to enhance corrosion resistance, reduce galling during installation, or improve sealing performance.
[00104] Alternative mounting techniques, such as snap fitting and gluing, may provide easy connection of the gas deflector 114 on the surface of the 5 housing 108 while maintaining effecting sealing and mechanical attachment. In one example embodiment, gluing the first end 124a of the hollow tubular body 124 with surface of the housing 108 may create a permanent bond between the gas deflector 114 and the gas vent 112 through the application of adhesive materials. The adhesive selection may 10 consider factors such as temperature resistance, chemical compatibility with expelled gases, cure time requirements, and long-term durability under thermal cycling conditions.
[00105] In another embodiment, snap fitting may offer an easy and quick connection between the gas deflector 114 and the surface of the housing 15 108. The snap fit may incorporate flexible elements on either the first end 124a of the hollow tubular body 124 or the housing 108 of the battery pack 106 that deflect during assembly and return to their original position to create mechanical retention. The snap fit geometry may include features such as cantilever beams, torsional elements, or annular rings that provide 20 the flexibility and retention force characteristics appropriate for the application.
[00106] Fig. 9A illustrates a perspective view of a first end cap 134, in accordance with an implementation of the present subject matter. Fig. 9B illustrates a bottom view of the first end cap 134, in accordance with an 25 implementation of the present subject matter. Fig. 9C illustrates a top view of the first end cap, in accordance with an implementation of the present subject matter. For the sake of ease of explanation, Figs. 9A-9C are explained together.
[00107] As mentioned above, the exhaust cap 130 may include the first 30 end cap 134. In one embodiment, the first end cap 134 may be connected 22
to the second end 124b of the hollow tubular body 124. The first end cap 134 may have a tapered conical tip. The tapered conical tip of the first end cap 134 may facilitate a controlled release of the expelled gases from the gas deflector 114. The tapered conical tip of the first end cap 134 may also streamline the expelled gases, thereby avoiding the chances of contact of 5 the expelled gases with the vehicle’s combustible components, such as the battery pack 106, or the rider.
[00108] Fig. 10A illustrates a perspective view of a second end cap 136, in accordance with an implementation of the present subject matter. Fig. 10B illustrates a top view of the second end cap 136, in accordance with an 10 implementation of the present subject matter. Fig. 10C illustrates a bottom view of the second end cap 136, in accordance with an implementation of the present subject matter. For the sake of ease of explanation, Figs. 10A-10C are explained together.
[00109] As mentioned above, the exhaust cap 130 may include the 15 second end cap 136. In one embodiment, the second end cap 136 may enclose the first end cap 134. In another embodiment, the second end cap 136 may have a semicircular tip.
[00110] In one embodiment, the second end cap 136 further quenches the flames due to the semicircular tip, thereby ensures that the expelled 20 gases do not contain any flames or the combustible substance which in turn increases the safety of the rider.
[00111] Although the subject matter has been described in considerable detail with reference to certain examples and implementations thereof, other implementations are possible. As such, the present disclosure should not 25 be limited to the description of the preferred examples and implementations contained therein. 23
I/We Claim:
1. An electric vehicle (EV) (100), comprising:
a frame (102) having at least one cross member mounted on the left-hand side (LH) of the frame (102) and at least one cross member 5 mounted on the right-hand side (RH) of the frame (102) to form an enclosure (138);
a battery pack (106) supported within the enclosure, such that a LH cross member (104) aligns with a first sidewall (110a) of a housing (108) of the battery pack (106), a RH cross member aligns with a second sidewall 10 (110b) opposite of the first sidewall (110a) of the housing (108), and at least one sidewall (140a) connecting the first sidewall (110a) and the second sidewall (110b) is located at a front (140) of the enclosure (138);
wherein at least one gas vent (112) is provided on a surface of the housing (108) of the battery pack (106), and wherein the at least one 15 gas vent (112) is to expel gases produced within the battery pack (106) during a thermal runaway event;
at least one gas deflector (114) provided as a flame quenching vent path, the at least one gas deflector (114) having a hollow tubular body (124) with a first end (124a) and a second end (124b), 20
wherein the first end (124a) of the hollow tubular body (124) is connected to the at least one gas vent (112), and wherein the second end (124b) of the hollow tubular body (124) is oriented towards the front (140) of the enclosure (138).
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2. The electric vehicle (100) as claimed in claim 1, wherein the at least one gas vent (112) is provided on the at least one sidewall (140a) located at the front (140) of the enclosure (138).
3. The electric vehicle (100) as claimed in claim 2, wherein the battery 30 pack comprises a plurality of modules (122) configured such that vents 24
(116) of the cells of the modules (122) face each other along a venting channel (118) common to the plurality of modules (122); and wherein the at least one gas vent (114) provided on the housing (108) is coupled to the common venting channel (118).
5
4. The electric vehicle (100) as claimed in claim 1, wherein the at least one gas vent (112) is provided on the first sidewall (110a) and the second sidewall (110b).
5. The electric vehicle (100) as claimed in claim 4, wherein the at least 10 one gas vent (112) provided on the first sidewall (110a) and the second sidewall (110b) is connected to the first end (124a) of the hollow tubular body (124); and
wherein the hollow tubular body (124) is L shaped.
15
6. The electric vehicle (100) as claimed in claim 1, wherein the at least one gas deflector (114) comprises a perforated cylindrical tube (128) within the hollow tubular body (124).
7. The electric vehicle (100) as claimed in claim 6, wherein the 20 perforated cylindrical tube (128) is encapsulated by a layer of an insulating wool (130).
8. The electric vehicle (100) as claimed in claim 1, wherein the first end (124a) of the hollow tubular body (124) is connected to the at least one gas 25 vent (112) by one of:
engaging an external male threads formed on the first end (124a) of the hollow tubular body (124) to an internal female threads formed on the surface of the housing (108); and
connecting the first end (124a) of the hollow tubular body (124) to the 30 at least one gas vent (112) through at least one of gluing or snap fitting the 25
first end (124a) of the hollow tubular body (124) with the surface of the housing 108.
9. The electric vehicle (100) as claimed in claim 1, wherein the gas deflector (114) comprises an exhaust cap (132) attached to the second end 5 (124b) of the hollow tubular body (124);
wherein the exhaust cap (132) comprises at least one of a first end cap (134) and a second end cap (136),
wherein the first end cap (134) is enclosed within the second end cap (136); 10
wherein the first end cap (134) has a conical tapered tip; and
wherein the second end cap (16) has a semicircular tapered tip.
10. The electric vehicle (100) as claimed in claim 6, wherein the hollow tubular body (124) and the perforated cylindrical tube (128) are made 15 up of at least one of aluminum, stainless steel, brass, and high-grade plastic or a combination thereof.
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26
ABSTRACT
FLAME QUENCHING VENT PATH FOR BATTERY PACKS IN ELECTRIC VEHICLES
An electric vehicle (EV) (100) comprises an enclosure (138) to 5 support a battery pack (106). At least one gas vent (112) is provided on a surface of a housing (108) of the battery pack (106) to expel gases produced within the battery pack (106) during a thermal runaway event. At least one gas deflector (114) has a hollow tubular body (124) with a first end (124a) and a second end (124b). The first end (124a) of the hollow tubular body 10 (124) is connected to the at least one gas vent (112), whereas the second end (124b) of the hollow tubular body (124) is oriented towards the front (140) of the enclosure (138).
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27 , Claims:I/We Claim:
1. An electric vehicle (EV) (100), comprising:
a frame (102) having at least one cross member mounted on the left-hand side (LH) of the frame (102) and at least one cross member 5 mounted on the right-hand side (RH) of the frame (102) to form an enclosure (138);
a battery pack (106) supported within the enclosure, such that a LH cross member (104) aligns with a first sidewall (110a) of a housing (108) of the battery pack (106), a RH cross member aligns with a second sidewall 10 (110b) opposite of the first sidewall (110a) of the housing (108), and at least one sidewall (140a) connecting the first sidewall (110a) and the second sidewall (110b) is located at a front (140) of the enclosure (138);
wherein at least one gas vent (112) is provided on a surface of the housing (108) of the battery pack (106), and wherein the at least one 15 gas vent (112) is to expel gases produced within the battery pack (106) during a thermal runaway event;
at least one gas deflector (114) provided as a flame quenching vent path, the at least one gas deflector (114) having a hollow tubular body (124) with a first end (124a) and a second end (124b), 20
wherein the first end (124a) of the hollow tubular body (124) is connected to the at least one gas vent (112), and wherein the second end (124b) of the hollow tubular body (124) is oriented towards the front (140) of the enclosure (138).
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2. The electric vehicle (100) as claimed in claim 1, wherein the at least one gas vent (112) is provided on the at least one sidewall (140a) located at the front (140) of the enclosure (138).
3. The electric vehicle (100) as claimed in claim 2, wherein the battery 30 pack comprises a plurality of modules (122) configured such that vents 24
(116) of the cells of the modules (122) face each other along a venting channel (118) common to the plurality of modules (122); and wherein the at least one gas vent (114) provided on the housing (108) is coupled to the common venting channel (118).
5
4. The electric vehicle (100) as claimed in claim 1, wherein the at least one gas vent (112) is provided on the first sidewall (110a) and the second sidewall (110b).
5. The electric vehicle (100) as claimed in claim 4, wherein the at least 10 one gas vent (112) provided on the first sidewall (110a) and the second sidewall (110b) is connected to the first end (124a) of the hollow tubular body (124); and
wherein the hollow tubular body (124) is L shaped.
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6. The electric vehicle (100) as claimed in claim 1, wherein the at least one gas deflector (114) comprises a perforated cylindrical tube (128) within the hollow tubular body (124).
7. The electric vehicle (100) as claimed in claim 6, wherein the 20 perforated cylindrical tube (128) is encapsulated by a layer of an insulating wool (130).
8. The electric vehicle (100) as claimed in claim 1, wherein the first end (124a) of the hollow tubular body (124) is connected to the at least one gas 25 vent (112) by one of:
engaging an external male threads formed on the first end (124a) of the hollow tubular body (124) to an internal female threads formed on the surface of the housing (108); and
connecting the first end (124a) of the hollow tubular body (124) to the 30 at least one gas vent (112) through at least one of gluing or snap fitting the 25
first end (124a) of the hollow tubular body (124) with the surface of the housing 108.
9. The electric vehicle (100) as claimed in claim 1, wherein the gas deflector (114) comprises an exhaust cap (132) attached to the second end 5 (124b) of the hollow tubular body (124);
wherein the exhaust cap (132) comprises at least one of a first end cap (134) and a second end cap (136),
wherein the first end cap (134) is enclosed within the second end cap (136); 10
wherein the first end cap (134) has a conical tapered tip; and
wherein the second end cap (16) has a semicircular tapered tip.
10. The electric vehicle (100) as claimed in claim 6, wherein the hollow tubular body (124) and the perforated cylindrical tube (128) are made 15 up of at least one of aluminum, stainless steel, brass, and high-grade plastic or a combination thereof.
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