Description:FIELD OF THE INVENTION
[0001] The present subject matter is related, in general to an energy storage pack, and more particularly, but not exclusively to a venting structure for the energy storage pack.
BACKGROUND OF THE INVENTION
[0002] A typical battery pack comprises of a plurality of cells which are interconnected in a series configuration or a parallel configuration or a combination of series and parallel configuration based on current, voltage and capacity requirements in the desired function. Battery packs are additionally sealed to improve reliability and meet waterproof and dustproof requirements.
[0003] During operation of battery pack when the battery pack is subjected to altitude changes and battery heating, there is a difference between the internal pressure of the battery pack and the external pressure of the operating environment which damages the sealing surface and results in battery failure.
[0004] Battery heating is generally caused due to fire or explosion, chemical reactions, chemical risk due to toxic liquids and gases, short circuit and even nail penetration events which results in thermal runaway.
[0005] Thermal runaway in batteries relates to an accelerated release of heat inside a battery cell due to uncontrolled exothermic reactions. In scenarios of uncontrolled exothermic reactions, the battery cells can no longer dissipate the heat as quickly as the heat is generated in the battery cell, ultimately leading to a loss of thermal stability of the battery cell. The heat generated in the battery cells during thermal runaway can propagate to neighboring electrical or electronic components leading to catastrophic failure.
[0006] In battery technology, lithium-ion batteries have attained significant popularity due to high energy density, high power density, excellent cycle performance and environmental friendliness. However, lithium-ion batteries have great propensity of catastrophic failure in events of thermal runaway as the heat energy released from a single failing lithium-ion cell during thermal runaway can cause a chain reaction in the neighboring lithium-ion cells.
[0007] Venting systems allow the expanding gases generated inside the battery pack during thermal runaway or internal pressure to escape, in order to prevent any further damage to the remaining components of the battery pack. Thus, there is a requirement of a novel venting system which can withstand high temperatures of thermal runaway and protect the battery pack from internal pressure raises as well as regulate the flow of gases during thermal runaway.
[0008] Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of described systems with some aspects of the present disclosure, as set forth in the remainder of the present application and with reference to the drawings.
SUMMARY
[0009] The following summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described below, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
[00010] According to embodiments illustrated herein, the present disclosure provides a venting structure. The venting structure comprises a bottom cover, a top cover, a support structure, a spring, and a disc. The bottom cover comprising of a plurality of openings configured to ingress gases into the venting structure. The top cover comprising a plurality of exit slots configured to egress the gases from the venting structure. The support structure is connected to a disc and a spring, and wherein the disc is configured to move in a lengthwise direction of the support structure based on a pressure of the ingress gases.
[00011] According to embodiments illustrated herein, the orientation of the venting structure depends on the pressure of the ingress gases in comparison to a pre-defined threshold pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
[00012] The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention.
[00013] Figure 1 illustrates a perspective view of an energy storage pack, in accordance with some embodiments of the present disclosure.
[00014] Figure 2 illustrates an exploded view of the venting structure depicting one or more components of the venting structure, in accordance with some embodiments of the present disclosure.
[00015] Figure 3 illustrates an exploded view of the venting structure depicting one or more components of the venting structure, in accordance with some embodiments of the present disclosure.
[00016] Figure 4 illustrates a front view of the venting structure when the pressure of ingress gases is less than the pre-defined threshold pressure, in accordance with some embodiments of the present disclosure.
[00017] Figure 5 illustrates a front view of the venting structure when the pressure of ingress gases is more than the pre-defined threshold pressure, in accordance with some embodiments of the present disclosure.
[00018] Figure 6a, 6b, 6c illustrates an exemplary embodiment of the bottom cover, in accordance with some embodiments of the present disclosure.
[00019] Figure 7a, 7b, 7c illustrates an exemplary embodiment of the top cover, in accordance with some embodiments of the present disclosure.
[00020] Figure 8a, 8b, 8c illustrates an exemplary embodiment of the disc, in accordance with some embodiments of the present disclosure.
DETAILED DESCRIPTION OF THE INVENTION
[00021] The present disclosure may be best understood with reference to the detailed figures and description set forth herein. Various embodiments are discussed below with reference to the figures. However, those skilled in the art will readily appreciate that the detailed descriptions given herein with respect to the figures are simply for explanatory purposes as the methods and systems may extend beyond the described embodiments. For example, the teachings presented, and the needs of a particular application may yield multiple alternative and suitable approaches to implement the functionality of any detail described herein. Therefore, any approach may extend beyond the particular implementation choices in the following embodiments described and shown.
[00022] References to “one embodiment,” “at least one embodiment,” “an embodiment,” “one example,” “an example,” “for example,” and so on indicate that the embodiment(s) or example(s) may include a particular feature, structure, characteristic, property, element, or limitation but that not every embodiment or example necessarily includes that particular feature, structure, characteristic, property, element, or limitation. Further, repeated use of the phrase “in an embodiment” does not necessarily refer to the same embodiment.
[00023] The present invention now will be described more fully hereinafter with different embodiments. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather those embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the invention to those skilled in the art.
[00024] The present invention is illustrated with an energy storage pack. However, a person skilled in the art would appreciate that the present invention is not limited to an energy storage pack and certain features, aspects and advantages of embodiments of the present invention are applicable to other forms of battery packs or energy storage devices. The energy storage pack in accordance with the present disclosure is applicable to rechargeable as well as non-rechargeable variants of energy storage packs.
[00025] It is an object of the present subject matter to provide a venting structure which passively regulates internal pressure as well as gas ejection during thermal runaway.
[00026] To this end, the present subject matter discloses a venting structure comprising of a bottom cover, a top cover, a disc, a spring, and a support structure. The bottom cover comprises of a plurality of openings to ingress gases into the venting structure while the top cover comprises of a plurality of exit slots to egress gases from the venting structure. The disc moves against a spring along a lengthwise direction of the support structure based on the pressure of the ingress gases. Upon the pressure of the ingress gases being beyond a pre-defined threshold pressure, the spring goes into a compressed state with the disc positioned in a top portion of the venting structure to allow the ingress of gases through the plurality of openings and the egress of gases through the plurality of exit slots.
[00027] Thus, the present subject matter plays a twin role in passively regulating internal pressure of the energy storage pack on which the venting structure is disposed and also regulating the flow of gases from the energy storage pack to the outside environment during thermal runaway in the energy storage pack. Additionally, the cycle life, calendar life of the energy storage pack is improved.
[00028] In small cells such as 18650 cells, when the electrodes expand in the event of increased internal pressure or thermal runaway, the housing of the 18650 cells constrains the expansion of the electrolyte and additionally creates mechanical stresses in the 18650 cells which limits the life cycle of the 18650 cells. The housing of 18650 cells thus adversely affects the battery life cycle, electrolyte depletion and increase in mechanical stresses in the battery pack. The present subject matter through the disclosed configuration overcomes the drawbacks of the housing structure in 18650 cells.
[00029] Further, in some energy storage packs compression pads are provided which limit the expansion of the energy storage pack’s orientation due to generation of burnt gases inside the energy storage pack. The compression pads merely restrict the bulking of the energy storage packs without providing a mechanism to alleviate the internal pressure of the energy storage pack.
[00030] The present disclosure addresses this exact drawback of the conventional battery packs and protects the battery pack against malfunction, unprecedented halt in functioning and potential safety hazards.
[00031] It is a further object of the present subject matter to provide a venting structure that provides ingress protection against water and dust.
[00032] To this end, the present subject matter of the venting structure is configured to prevent ingress of water into the venting structure when submerged in 1m of water for 30 mins. Thus, the developed venting structure provides effective sealing against ingress of water through the venting structure. The disclosed configuration of the venting structure additionally prevents ingress of dust particles through the venting structure.
[00033] Additionally, the present subject matter of the venting structure in accordance with the disclosed configuration when ignited is configured to stop burning within 10 seconds of introduction of the flame into the venting structure. Thus, the present disclosure provides a fire-resistant venting structure.
[00034] The present subject matter in accordance with the present disclosure provide ease of assembly and serviceability when disposed on an outer surface of an energy storage pack. The venting structure being on an outer surface of the energy storage pack allows accessibility and ease of serviceability of the venting structure in the event of failure. Further, the simple disposition of the venting structure on an outer surface of the energy storage pack, enhances the ease of assembly of the entire energy storage pack.
[00035] The disclosed venting structure comprises of a compact design and is disposed on an outer surface of the energy storage pack which retains the aesthetics associated with the energy storage pack with additional safety features brought in by the functionality of the venting structure.
[00036] The present subject matter of the venting structure in accordance with the present configuration comprises of a top cover, a bottom cover, a spring, a support structure and a disc disposed in a compact layout. The components of the venting structure can be easily manufactured without major revamping of core manufacturing processes which makes implementation and the cost of introduction in energy storage packs reduced.
[00037] In accordance with the configuration of the disclosed subject matter, an additional advantage of the disclosed venting structure is the flexibility to manufacture variants in forms of size of the energy storage pack, range of power supply and capacity of the energy storage pack. The disclosed venting structure design can be easily implemented and modified in accordance with the electrical demands of the energy storage pack.
[00038] The embodiments of the present invention will now be described in detail with reference to an energy storage pack along with the accompanying drawings. However, the present invention is not limited to the present embodiments. 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.
[00039] Figure 1 illustrates a perspective view of an energy storage pack, in accordance with some embodiments of the present disclosure.
[00040] With reference to figure 1, 100 denotes an energy storage pack, 102 denotes an outside surface of the energy storage pack and 200 denotes a venting structure.
[00041] In an aspect, the venting structure (200) is disposed on an outside surface (102) of the energy storage pack (100).
[00042] In an embodiment, the energy storage pack (100) disclosed in relation to the present subject matter includes any electrical energy storage device or system configured to store electrical energy and may include a battery pack, a plurality of battery cells, a plurality of battery modules and other forms of electrical energy storage equipment. The energy storage pack can be of rechargeable as well as non-rechargeable variant and is configured to have a charged and discharged state. In a charged state of the battery pack, the battery pack supplies the stored electrical energy to an external electrical load, an electrical or electronic equipment, electric or hybrid vehicle as and when required.
[00043] In an embodiment, the energy storage pack comprises of lithium-ion cells. Lithium-ion batteries are characterized by high energy density, high power density, excellent cycle performance and environmental friendliness. The apprehension in usage of Lithium-ion cells is the uncontrolled exothermic reaction occurring in thermal runaway of Lithium-ion cells are fast, violent and self-accelerating.
[00044] In an embodiment, the outside surface (102) of the energy storage pack (100) is composed of a material and the material is a metal being composed of at least one of nickel, aluminium, copper, steel, zinc. In another embodiment, the outside surface (102) of the energy storage pack (100) is composed of a plastic material.
[00045] In an aspect, the venting structure (200) is configured to regulate the internal pressure developed inside the energy storage pack (100) and also eject gases from inside the energy storage pack (100) to an outside environment in the event of occurrence of thermal runaway in the energy storage pack (100) or more specifically when the pressure of gases in the energy storage pack (100) goes beyond a pre-defined threshold pressure for which the venting structure (200) is designed.
[00046] Figure 2 illustrates an exploded view of the venting structure depicting one or more components of the venting structure, in accordance with some embodiments of the present disclosure.
[00047] With reference to Figure 2, 200 denotes the venting structure, 202 denotes a top cover of the venting structure, 204 denotes a disc, 206 denotes a bottom cover of the venting structure, 208 denotes a plurality of exit slots of the top cover and 210 denotes a plurality of openings of the bottom cover.
[00048] In an aspect, the venting structure (200) comprises of a bottom cover (206), a top cover (202) and a disc (202). The top cover (202), the disc (204) and the bottom cover (206) are disposed along a lengthwise direction of the venting structure (200) along the same vertical axis.
[00049] In an embodiment, the bottom cover (206) comprises of a plurality of openings (210). The plurality of openings (210) is configured to allow the ingress of gases from an energy storage pack (100) into the venting structure (200).
[00050] In an embodiment, the top cover (202) comprises of a plurality of exit slots (208). The plurality of exit slots (208) is configured to egress the gases that had ingress into the venting structure (200).
[00051] In an aspect, the venting structure (200) is configured to receive ingress gases from inside the energy storage pack (100) and to egress gases via the plurality of exit slots (208), and wherein the venting structure (200) is disposed on an outer surface (102) of the energy storage pack (100).
[00052] In an embodiment, the disc (204) is positioned between the top cover (202) and the bottom cover (206). In an embodiment, the top cover (202), disc (204) and the bottom cover (206) are aligned along the same vertical axis of the venting structure (200).
[00053] In an aspect, the disc (204) is configured to move in a vertical direction based on the pressure of the gases that ingress through the plurality of openings (210) of the bottom cover (206).
[00054] In an embodiment, at least one of the plurality of openings (210) and the plurality of exit slots (208) having a breather or a membrane type opening.
[00055] Figure 3 illustrates an exploded view of the venting structure depicting one or more components of the venting structure, in accordance with some embodiments of the present disclosure.
[00056] With reference to Figure 3, 302 denotes a spring and 304 denotes a support structure.
[00057] In an aspect, the venting structure (200) additionally comprises of a spring (302) and a support structure (304).
[00058] In an embodiment, the spring (304) has a pre-defined stiffness and is configured to possess a rest state, an extended state and a compressed state based on the force applied on the spring (304).
[00059] In an embodiment, the spring (304) is composed of a material, the material being chosen from at least one of nickel, lead, tin, stainless steel, zinc, aluminium, high temperature resistant silicon and plastic.
[00060] In an aspect, the support structure (304) extends perpendicularly downward from a central portion of the top cover (202). The support structure (304) is connected to the disc (204) and the spring (302). In an embodiment, the spring (302) is positioned above the disc (204). In an embodiment, a bottom portion of the spring (302) is connected to a top surface of the disc (204).
[00061] In an aspect, the disc (204) is configured to move in a lengthwise direction of the support structure (304) based on the pressure of the gases that ingress from the plurality of openings (210) of the bottom cover (206). The pressure of the ingress gases are exerted on a bottom surface of the disc (204) which results in the movement of the disc (204) in a lengthwise direction of the support structure (304). The bottom surface of the disc (204) faces the plurality of openings (210) of the bottom cover (206).
[00062] In an aspect, the plurality of openings (210) and the plurality of exit slots (208) are designed to have enhanced area for ingress and egress respectively of gases from the energy storage pack (100). An enhanced area provides more space for venting of the gases from inside the energy storage pack (100) to the outside environment through the venting structure (200).
[00063] Figure 4 illustrates a front view of the venting structure when the pressure of ingress gases is less than the pre-defined threshold pressure, in accordance with some embodiments of the present disclosure.
[00064] With reference to figure 4, 402 denotes a top portion of the venting structure and 404 denotes a bottom portion of the venting structure.
[00065] In operation, when the pressure of the ingress gases acting on the disc (204) is below a pre-defined threshold pressure, the spring (302) is in a rest state while the disc (204) is positioned at the bottom portion (404) of the venting structure. In an embodiment, the disc (204) is disposed on the bottom cover (206).
[00066] In an aspect, the pressure of the ingress gases acts through the plurality of openings (210) of the bottom cover (206) and onto the bottom surface of the disc (204). The venting structure (200) is designed to have a pre-defined pressure threshold based on which the movement of the disc (204) along the lengthwise direction of the support structure (304) is configured. The pre-defined pressure threshold is based on the application and functionality of the energy storage pack (100) on which the venting structure (200) is disposed.
[00067] In an aspect, the rest state or a resting position of the spring (302) is a relaxed state of the spring (302) where the spring (302) is neither extended nor compressed. A typical rest state of the spring (302) denotes a length of the spring when it is not subjected to any form of load or forces acting upon it, or when it depicts an open-coiled design.
[00068] In an aspect, the disc (204) when subjected to the pressure of the ingress gases which is beyond the pre-defined threshold pressure, the disc (204) rests on a top surface of the bottom cover (206) such that the disc (204) covers the plurality of openings (210) of the bottom cover (206).
[00069] Figure 5 illustrates a front view of the venting structure when the pressure of ingress gases is more than the pre-defined threshold pressure, in accordance with some embodiments of the present disclosure.
[00070] In operation, when the pressure of the ingress gases acting on the disc (204) is beyond the pre-defined threshold pressure, the spring (302) attains a compressed state while the disc (204) is positioned at the top portion (402) of the venting structure (200).
[00071] In an aspect, when the pressure of the ingress gases is beyond the pre-defined threshold pressure, the pressure of the ingress gases acting on the bottom surface of the disc (204) through the plurality of openings (210) pushes the disc (204) upwards along the length of the support structure (304). The upward movement of the disc (204) allows the ingress of gases through the plurality of openings (210) into the venting structure (200). The ingress gases settle in a region between the disc (204) and the bottom cover (206) formed by the upward movement of the disc (204). The positioning of the disc (204) in the top portion (402) of the venting structure (200) permits uncovering of the plurality of exit slots (208) of the top cover (202), thus allowing escape or egress of the gases from the venting structure (200) to the outside environment through the plurality of exit slots (208).
[00072] In an aspect, a compressed state of the spring (302) is when a force, load or pressure be applied on the spring (302) such that it abandons its open-coiled design with the coils of the spring (302) being configured to tighten against each other.
[00073] With reference to Figure 4 and 5, the spring (302) is provided with a pre-defined stiffness based on the pre-defined threshold pressure.
[00074] In an aspect, the stiffness of a spring (302) is depicted by a spring constant and is defined with reference to Hooke’s Law. In common parlance, the stiffness of a spring may be defined as an ability of the spring to resist a force acting on it or a resistance offered by an elastic body, such as a spring, to deformation in response to an applied force. With reference to Hooke’s law, the spring constant is equal to the force applied on the elastic body divided by the change in length of the elastic body.
[00075] In an aspect, the pre-defined threshold pressure of the venting structure (200) being of a range of 0.2 bar to 0.7 bar.
[00076] Figure 6a, 6b, 6c illustrates an exemplary embodiment of the bottom cover, in accordance with some embodiments of the present disclosure.
[00077] For the sake of brevity, figure 6a, 6b and 6c will be explained in conjunction. Figure 6a illustrates a top perspective view of the bottom cover. Figure 6b illustrates a top view of the bottom cover. Figure 6c illustrates a front view of the bottom cover.
[00078] With reference to figure 6a, 6b and 6c, 602 denotes a peripheral portion of a top surface of the bottom cover, 604 denotes a bottom surface of the bottom cover, 606 denotes a plurality of cross members, 608 denotes a central portion of the bottom cover, 610 denotes a depression provided in the bottom cover.
[00079] In an aspect, the bottom cover (206) comprises of a plurality of cross member (606), a depression (610) and a peripheral portion (602).
[00080] In an aspect, the top cover (202) interfaces with the peripheral portion (602) of a top surface of the bottom cover (206).
[00081] In an aspect, the plurality of cross members (606) is provided on a bottom surface (604) of the bottom cover (206). The plurality of cross members (606) is integrated with the bottom cover (206) and extends from one end on a periphery of the bottom cover (206) to an opposite end of the periphery of the bottom cover (206). The plurality of cross members (606) intersects each other in a central portion (608) of the bottom cover (206) where a depression (610) is provided in the central portion (608). The depression (610) provides support for resting the support structure (304) of the top cover (202).
[00082] In an aspect, the depression (610) is configured to receive one end of the support structure (304) extending from the top cover (202).
[00083] In an aspect, the plurality of cross members (606) is configured to create the plurality of openings (210) in a sector wise manner within the bottom cover (206).
[00084] In an aspect, the plurality of cross members (606) of the bottom cover (206) enhance the structural rigidity of the bottom cover (206) by providing material strength. An increase in the plurality of cross member (606) integrated with the bottom cover (206) of the venting structure (200) accordingly increases the structural rigidity of the bottom cover (206).
[00085] In an embodiment, the bottom cover (206) of the venting structure (200) is provided with two cross members (606), intersecting each other at an angle of 90 degrees at the central portion (608) of the bottom cover (206). The intersection of the plurality of cross member (606) results in the creation of four openings having quadrant-like shape.
[00086] In an embodiment, the bottom cover (206) is composed of a material, the material being chosen from at least one of nickel, lead, tin, stainless steel, zinc, aluminium, high temperature resistant silicon and plastic.
[00087] Figure 7a, 7b, 7c illustrates an exemplary embodiment of the top cover, in accordance with some embodiments of the present disclosure.
[00088] For the sake of brevity, figure 7a, 7b and 7c will be explained in conjunction. Figure 7a illustrates a top view of the top cover. Figure 7b illustrates a bottom perspective view of the top cover. Figure 7c illustrates a front view of the top cover.
[00089] With reference to figure 7a, 7b and 7c, 702 denotes a bottom surface of the top cover, 704 denotes a peripheral region of the top cover, 706 denotes a slanted profile of the exit slots of the top cover, 708 denotes a pre-defined gap between the plurality of exit slots of the top cover.
[00090] In an aspect, the top cover (206) comprises of a support structure (304) and a peripheral region (704) comprising of a plurality of exit slots (208).
[00091] In an aspect, the support structure (304) is integrated with a bottom surface (702) of the top cover (202). The support structure (304) extends perpendicularly downward from a central portion of the bottom surface (702) of the top cover (206). The free end of the support structure (304) rests on the depression (610) provided in the bottom cover (206).
[00092] In an aspect, the top cover (202) comprises of a peripheral region (704) which extends in a downward direction along the periphery of the top cover (202). The peripheral region extends perpendicularly downward. A plurality of exit slots (208) is disposed along the peripheral region (704) of the top cover (202).
[00093] In an embodiment, at least one edge of each of the plurality of exit slots (208) comprising a slanted profile (706) to direct the egress gases to an outside environment. The plurality of exit slots (208) has a width of range of 2mm to 9mm and a height of range of 1mm to 5mm.
[00094] In an aspect, the slanted profile (706) is configured to streamline the of flow of the gases from the venting structure (200) to the outside environment, thus enhancing efficient and effective removal of the gases from the energy storage pack (100) to the outside environment through the venting structure (200). The slanted profile (706) of each exit slot (706) is achieved by the edge connecting an inner surface of the peripheral region (704) to an outer surface of the peripheral region (704) being at a pre-defined angle. The pre-defined angle being based on aerodynamic design required for streamlining the quicker egress of gases from the venting structure (200) through the plurality of exit slots (208) into the outside environment.
[00095] In an aspect, the plurality of exit slots (208) is positioned with pre-defined gap (708) between them to maintain structural rigidity of the top cover (202) of the venting structure (200). The pre-defined gap (708) permits material flow between the adjacent exit slots (208) to enhance the structural rigidity and strength of the top cover (202) of the venting structure.
[00096] In an embodiment, the top cover (202) is composed of a material, the material being chosen from at least one of nickel, lead, tin, stainless steel, zinc, aluminium, high temperature resistant silicon and plastic.
[00097] Figure 8a, 8b, 8c illustrates an exemplary embodiment of the disc, in accordance with some embodiments of the present disclosure.
[00098] For the sake of brevity, figure 8a, 8b and 8c will be explained in conjunction. Figure 8a illustrates a top view of the disc. Figure 8b illustrates a top perspective view of the disc. Figure 8c illustrates a front view of the disc.
[00099] With reference to figure 8a, 8b and 8c, 802 denotes a top surface of the disc, 804 denotes a bottom surface of the disc and 806 denotes a central slot of the disc.
[000100] In an aspect, the disc (204) comprises of a top surface (802), a bottom surface (804) and a central slot (806).
[000101] In an aspect, the disc (204) is provided with a central slot (806) to allow passage of the support structure (304) through the disc (204). The central slot (806) of the disc (204) ensures alignment of the disc (204) with reference to the support structure (304) and additional ensures that the movement of the disc (204) along the lengthwise direction of the support structure (304) is along the vertical axis of the support structure (304).
[000102] In an embodiment, the disc (204) is divided into a plurality of movable flaps using a plurality of slits, wherein the thickness of each of the plurality of movable flaps is different and wherein the plurality of movable flaps allows egress of gases to the outside environment.
[000103] In another embodiment, the disc (204) is divided into a plurality of movable flaps using a plurality of slits, wherein the thickness of each of the plurality of movable flaps is the same and wherein the plurality of movable flaps allows egress of gases to the outside environment.
[000104] In an embodiment, the disc (204) is manufactured as a conical structure. The conical structure comprises of a bottom surface (804) with a circular base tapering along the height of the disc (204) in a lengthwise direction of the support structure (304) to the top surface (802). The top surface (802) converging with the central slot (806) provided on the disc (204). The surface area of the conical structure is divided into a plurality of movable flaps using a plurality of slits wherein each movable flap having a different thickness such that based on varying pressure of the ingress gases from the energy storage pack (100) a dedicated movable flap moves to allow the egress of the gases to the outside environment from the venting structure (200). Each movable flap is having a pre-defined thickness based on the pre-defined pressure threshold the dedicated movable flap is designed for.
[000105] In an embodiment, the disc (204) having a conical structure, has the surface area of the conical structure divided into a plurality of movable flaps by a plurality of slits with each movable flap having the same thickness and designed for the same value of pre-defined pressure threshold. Upon the pressure of the ingress gases being beyond the pre-defined pressure threshold, the plurality of movable flaps by an upward swing motion allows escape of the ingress gases through the disc (204) and then through the plurality of exit slots (208) into the outside environment.
[000106] In an embodiment, the disc (204) comprises of a truncated cone structure with a top surface (802) having larger cross-sectional area than a bottom surface (804).
[000107] In an embodiment, the disc (204) is a circular disc of uniform thickness where the cross-sectional are of the top surface (802) is equal to the cross-sectional area of the bottom surface (804).
[000108] In an embodiment, the disc (204) is manufactured to have a uniform thickness. In an embodiment, the disc (204) is manufactured to have a non-uniform thickness.
[000109] In an embodiment, the disc (204) is composed of rubber cork material. In an embodiment, the disc (204) is composed of a material with elastic properties making the disc (204) capable of pre-defined deformation upon the application of an external force on the disc (204).
[000110] The terms “an embodiment”, “embodiment”, “embodiments”, “the embodiment”, “the embodiments”, “one or more embodiments”, “some embodiments”, and “one embodiment” mean “one or more (but not all) embodiments of the invention(s)” unless expressly specified otherwise. The terms “including”, “comprising”, “having” and variations thereof mean “including but not limited to”, unless expressly specified otherwise. The terms “a”, “an” and “the” mean “one or more”, unless expressly specified otherwise.
[000111] The disclosed venting structure (200) not only passively regulate the internal pressure in an energy storage pack (100) but also ejects gases formed inside the energy storage pack (100) during thermal runaways. The venting structure (200) thus performs a twin role in improving the life cycle, performance and the safe operation of the energy storage pack (100).
[000112] The disclosed configuration of the venting structure (200) additionally enhances ease of serviceability, accessibility, assembly and manufacturability of the venting structure (200). The disclosed venting structure (200) encompasses a compact design and is disposed on the energy storage pack (100) whilst maintaining aesthetics of the energy storage pack (100). The venting structure (200) additionally protects the energy storage pack (100) against malfunction, unprecedented halt in functioning and potential safety hazards. Thus, the safety of the energy storage pack (100) is ensured during abnormal functioning and the same is appropriately addressed through the venting structure (200) configuration.
[000113] The venting structure (200) in accordance with the present disclosure has been accorded V0 classification under the UL 94 plastics flammability standards. Under the V0 classification, the component when ignited prevent propagation of the flame with the burning stopping in 10 seconds on a vertical part without any flaming drips off the component.
[000114] Further, the venting structure (200) in accordance with the disclosed configuration is accorded Ingress protection Code IP67 rating which indicates that the venting structure (200) is waterproof and also provides complete protection against dust over an extended period of time. The venting structure (200) when submersed in 1m depth of water for 30 mins, provides protection against the ingress of water through the venting structure (200).
[000115] The venting structure in accordance with the disclosed configuration is in compliance with TSE779 lithium-ion battery safety standards.
[000116] With reference to AIS 156 standards (Amendment 2), Rechargeable Energy Storage System (referred to as REESS) shall have pressure release vents provided to avoid building up of internal pressure and release of gases in case of internal single cell short circuit. To this end, the disclosed venting structure (200) disposed on an energy storage pack (100) regulates the internal pressure of the energy storage pack (100) and also ejects gases from inside the energy storage pack (100) in the event of thermal runaway.
[000117] The venting structure in accordance with the present configuration when disposed on an energy storage pack (100) is in compliance with UL2271 standard certification for lithium-ion battery and battery pack safety. Under the UL2271 standards, the energy storage pack (100) has to pass thermal runaway test, overcharge test, over discharge test, crush test, external short-circuit test, impact test, water immersion test, thermal cycling test, vibration test and forced discharge test. The energy storage pack (100) disposed with the venting structure (200) is in compliance with the UL2271 standard certification.
[000118] A description of an embodiment with several components in communication with another does not imply that all such components are required, On the contrary, a variety of optional components are described to illustrate the wide variety of possible embodiments of the invention,
[000119] Finally, the language used in the specification has been principally selected for readability and instructional purposes, and it may not have been selected to delineate or circumscribe the inventive subject matter and is therefore intended that the scope of the invention be limited not by this detailed description, but rather by any claims that issue on an application based here on. Accordingly, the embodiments of the present invention are intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.
[000120] While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
[000121] A person with ordinary skills in the art will appreciate that the systems, modules, and sub-modules have been illustrated and explained to serve as examples and should not be considered limiting in any manner. It will be further appreciated that the variants of the above disclosed system elements, modules, and other features and functions, or alternatives thereof, may be combined to create other different systems or applications.
[000122] Those skilled in the art will appreciate that any of the aforementioned steps and/or system modules may be suitably replaced, reordered, or removed, and additional steps and/or system modules may be inserted, depending on the needs of a particular application.
[000123] While the present disclosure has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from its scope. Therefore, it is intended that the present disclosure not be limited to the particular embodiment disclosed, but that the present disclosure will include all embodiments falling within the scope of the appended claims.

LIST OF REFERENCE NUMERALS:
100 – Energy storage pack 802- top surface of disc
102 – Outer surface 804- bottom surface of disc
200 – Venting Structure 806- central slot of disc
202 – Top Cover
204 - Disc
206 – Bottom Cover
208 – Plurality of Exit Slots
210 – Plurality of openings
302 - Spring
304 – Support Structure
402 – Top portion of the venting structure
404 – Bottom portion of the venting structure
602 – peripheral portion of bottom cover
604- bottom surface of bottom cover
606- plurality of cross members
608- central portion of bottom cover
610- depression in bottom cover
702- bottom surface of top cover
704- peripheral region of top cover
706- slanted profile of exit slots
708- pre-defined gap between exit slots
, C , Claims:We claim:
1. A venting structure (200), the venting structure (200) comprising:
a bottom cover (206), the bottom cover (206) comprising a plurality of openings (210), the plurality of openings (210) being configured to ingress gases into the venting structure (200);
a top cover (202), the top cover (202) comprising a plurality of exit slots (208), wherein the plurality of exit slots (208) being configured to egress the gases from the venting structure (200);
a support structure (304),
wherein the support structure (304) being connected to a disc (204) and a spring (302), and
wherein the disc (204) being configured to move in a lengthwise direction of the support structure (304) based on a pressure of ingress gases.
2. The venting structure (200) as claimed in claim 1, wherein when the pressure of ingress gases being below a pre-defined threshold pressure, the venting structure (200) being configured such that:
the spring (302) being in a rest state; and
the disc (204) being positioned in a bottom portion (404) of the venting structure (200), wherein the disc (204) being disposed on the bottom cover (206).
3. The venting structure (200) as claimed in claim 2, wherein when the pressure of ingress gases being beyond the pre-defined threshold pressure, the venting structure (200) being configured such that:
the spring (302) being in a compressed state; and
the disc (204) being positioned in a top portion (402) of the venting structure (200) by an upward movement of the disc (204) along the length of the support structure (304) to allow ingress of the gases through the plurality of openings (210) and egress of the gases through the plurality of exit slots (208).
4. The venting structure (200) as claimed in claim 3, wherein the spring (302) being provided with a pre-defined stiffness based on the pre-defined threshold pressure.
5. The venting structure (200) as claimed in claim 4, wherein the pre-defined threshold pressure being of a range of 0.2 bar to 0.7 bar.
6. The venting structure (200) as claimed in claim 1, wherein the top cover (202) interfaces with a peripheral portion (602) of a top surface of the bottom cover (206).
7. The venting structure (200) as claimed in claim 1, wherein the bottom cover (206) comprising:
a plurality of cross members (606) provided on a bottom surface (604) of the bottom cover (206),
wherein the plurality of cross members (606) being integrated with the bottom cover (206) and extending from one end on a periphery of the bottom cover to an opposite end of the periphery of the bottom cover (206),
wherein the plurality of cross members (606) intersect each other in a central portion (608) of the bottom cover (206),
wherein a depression (610) being provided in the central portion (608), the depression (610) provides support for resting the support structure (304) of the top cover (202); and
wherein the plurality of cross members (606) being configured to create the plurality of openings (210) in a sector wise manner within the bottom cover (206).
8. The venting structure (200) as claimed in claim 1, wherein the top cover (202) comprises:
the support structure (304) being integrated with a bottom surface (702) of the top cover (202), wherein the support structure (304) extends perpendicularly downward from a central portion of the top cover (202); and
the plurality of exit slots (208) being disposed along a peripheral region (704) of the top cover (202), wherein the peripheral region (704) extends in a downward direction along the periphery of the top cover (202).
9. The venting structure (200) as claimed in claim 1, wherein the disc (204) is divided into a plurality of movable flaps using a plurality of slits, wherein thickness of each of the plurality of movable flaps is different and wherein the plurality of movable flaps allows egress of the gases to the outside environment.
10. The venting structure (200) as claimed in claim 1, wherein at least one edge of each of the plurality of exit slots (208) comprising a slanted profile (706) to direct the gases to be egressed to an outside environment and the plurality of exit slots (208) having a width of range of 2mm to 9mm and a height of range of 1mm to 5mm.
11. The venting structure (200) as claimed in claim 1, wherein the plurality of exit slots (208) being positioned with pre-defined gap (708) between them to maintain structural rigidity of the top cover (202) of the venting structure (200).
12. The venting structure (200) as claimed in claim 1, wherein the disc (204) comprises a truncated cone structure with a top surface (802) having larger cross-sectional area than a bottom surface (804).
13. The venting structure (200) as claimed in claim 1, wherein the disc (204) being provided with a central slot (806) to allow passage of the support structure (304) through the disc (204).
14. The venting structure (200) as claimed in claim 1, wherein the spring (302) being positioned above the disc (204).
15. The venting structure (200) as claimed in claim 1, wherein the disc (204) being manufactured to have a uniform thickness.
16. The venting structure (200) as claimed in claim 1, wherein the disc (204) being manufactured to have a non-uniform thickness.
17. The venting structure (200) as claimed in claim 1, wherein the venting structure (200) comprising:
the bottom cover (206), the top cover (202), the spring (302) and the support structure (304) being composed of at least one of nickel, lead, tin, stainless steel, zinc, aluminum, high temperature resistant silicon and plastic; and
the disc (204) being composed of rubber cork material.
18. The venting structure (200) as claimed in claim 1, wherein the venting structure (200) being configured to receive ingress of the gases from inside an energy storage pack (100) and configured to egress the gases via the plurality of exit slots, and wherein the venting structure (200) being disposed on an outer surface (102) of the energy storage pack (100).