Battery pack with improved safety

Abstract

A battery pack according to one embodiment of the present invention includes a cell module assembly including a battery cell stack in which a plurality of battery cells are stacked and each battery cell is vertically erected; a plate-shaped blocking member disposed between adjacent battery cells and vertically erected; a pack case having an open top and configured to house the cell module assembly; and a fire tank located on top of the cell module assembly and covering the top of the pack case, the blocking member including a plurality of openings at an upper end, and an empty space connected to the plurality of openings within the blocking member.

Description

Technical Field

[0001] (Cross - reference to related applications) This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0188506 filed on December 27, 2021, and Korean Patent Application No. 10-2022-0169562 filed on December 7, 2022, and all the contents disclosed in the documents of the Korean patent applications are incorporated herein by reference. (Technical field) The present invention relates to a battery, and more particularly, to a battery pack configured to ensure safety even when a thermal event occurs.

Background Art

[0002] Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium secondary batteries, etc. Among them, lithium secondary batteries have attracted attention because they have almost no memory effect compared to nickel-based secondary batteries, can be charged and discharged freely, have a very low self-discharge rate, and have a high energy density.

[0003] Such lithium secondary batteries mainly use lithium-based oxides and carbon materials as the positive electrode active material and the negative electrode active material, respectively. A lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate coated with such a positive electrode active material and a negative electrode active material are disposed with a separator therebetween, and an exterior material that hermetically stores the electrode assembly together with an electrolytic solution, that is, a battery case.

[0004] Generally, lithium secondary batteries can be classified into a can-type secondary battery in which an electrode assembly is built into a metal can and a pouch-type secondary battery in which an electrode assembly is built into a pouch of an aluminum laminate sheet according to the shape of the exterior material.

[0005] Such secondary batteries are widely used not only in small devices such as portable electronic devices but also in medium and large-sized devices such as electric vehicles and energy storage systems (ESS), and the degree of their use is increasing rapidly. Recently, there has been an increasing tendency to use residential battery packs for power storage purposes.

[0006] In various battery packs including such residential battery packs, a plurality of battery cells (secondary batteries) are included in order to increase the capacity and / or output. In particular, in order to increase the energy density of the battery pack, a plurality of battery cells are often arranged in a very narrow space in a densely packed state.

[0007] In such a configuration of a battery pack, one of the typical important problems is safety. In particular, when a thermal event occurs in any one of the plurality of battery cells included in the battery pack, such an event needs to be suppressed from being propagated to other battery cells. If the thermal propagation between battery cells is not well suppressed, this may cause thermal events in many battery cells included in the battery pack, leading to more serious problems such as ignition or explosion of the battery pack. In addition, the ignition or explosion that occurs in the battery pack may cause significant damage to the surrounding lives and property. In particular, in the case of a residential battery pack, when ignition or explosion occurs, it may endanger the safety of the people living in the house and may spread to a fire in the house, causing more serious damage. Summary of the Invention Problems to be Solved by the Invention

[0008] Therefore, the present invention was devised to solve the above problems, and an object thereof is to provide a battery pack and the like whose structure is improved so as to be able to suppress cell-to-cell transfer when a thermal event occurs inside the battery pack.

[0009] However, the technical problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

Means for Solving the Problems

[0010] A battery pack according to one aspect of the present invention for achieving the above object includes a plurality of battery cells; a blocking member configured to block heat interposed between adjacent battery cells; a pack case that houses the plurality of battery cells and the blocking member in an internal space; and a fire extinguishing tank that holds a fire extinguishing agent and is disposed above the cell assembly.

[0011] Here, the blocking member may be configured in a form in which a heat insulating material is interposed between metal plates.

[0012] The metal plate may be made of aluminum.

[0013] The heat insulating material may be a mica sheet or a compression paper.

[0014] The fire extinguishing tank may be configured to discharge a fire extinguishing agent to the cell assembly side when heat is applied from the cell assembly.

[0015] The blocking member may be configured to allow the fire extinguishing agent discharged from the fire extinguishing tank to flow in.

[0016] In addition, an energy storage system according to another aspect of the present invention includes the battery pack according to the present invention.

[0017] A battery pack according to an embodiment of the present invention includes a cell module assembly including a battery cell stack in which a plurality of battery cells are stacked and each battery cell is erected in the vertical direction; a plate-shaped blocking member disposed between adjacent battery cells and erected in the vertical direction; a pack case adapted to house the cell module assembly and having an open upper surface; and a fire extinguishing tank located above the cell module assembly and covering the upper surface of the pack case. The blocking member may include a plurality of openings at an upper end, and the interior of the blocking member may include an empty space connected to the plurality of openings.

[0018] When a thermal event occurs in the battery cell, the fire extinguishing agent provided from the fire extinguishing tank can flow into the empty space inside the blocking member through the plurality of openings of the blocking member.

[0019] The blocking member may include a support plate and a pair of swelling pads provided on both surfaces of the support plate.

[0020] The support plate may include a plurality of first through holes formed to penetrate the support plate in one direction from the plurality of openings, and the interior of the plurality of first through holes may be the empty space inside the blocking member.

[0021] The first through holes extend in the vertical direction of the support plate, and each of the plurality of first through holes may be arranged in a row parallel to each other.

[0022] To allow the fire extinguishing agent to stay inside the plurality of first through holes, the lower ends of the plurality of first through holes are opened at the lower end of the support plate, and the lower end of the support plate is arranged to be in close contact with or adhered to the lower surface of the pack case, or the lower ends of the plurality of first through holes may be in a closed shape.

[0023] The support plate further includes a plurality of second through holes, and the plurality of first through holes and the plurality of second through holes extend in different directions and intersect with each other, and the interiors of the plurality of first through holes and the plurality of second through holes can be the empty spaces inside the blocking member.

[0024] Both ends of the plurality of second through holes can each be in a closed shape.

[0025] The first through holes extend in the vertical direction of the support plate, and each of the plurality of first through holes is arranged in a row parallel to each other. The second through holes extend in the length direction of the support plate, and each of the plurality of second through holes can be arranged in a row parallel to each other.

[0026] The support plate is made of metal or stainless steel, and the swelling pad can be made of silicone or soft plastic.

[0027] The support plate can be formed by joining a pair of support plate members that are symmetrically formed about the cross-section in the length direction of the support plate.

[0028] The support plate can be integrally formed.

[0029] The fire extinguishing agent can be a fire extinguishing agent in a liquid state.

[0030] The fire extinguishing tank includes an internal space for storing a fire extinguishing agent; and a portion where the thickness of the base plate of the fire extinguishing tank is relatively thin, and can include a plurality of weak portions that are melted and opened by a thermal event of the battery cell.

[0031] The weak portions are linear, arranged parallel to one edge of the fire extinguishing tank, each weak portion is arranged parallel to each other, and the length direction of the weak portions and the length direction of the battery cell can be perpendicular to each other.

[0032] The cell module assembly includes a pair of bus bar housings disposed on the front and rear surfaces of the stack of battery cells; and a pair of end plates disposed parallel to the battery cells at both side ends of the stack of battery cells, and the pair of end plates can connect between the pair of bus bar housings.

[0033] The battery packs are provided in a plurality and can be stacked in the vertical direction, and the battery packs stacked vertically can be coupled to each other by mechanical connection and electrical connection.

[0034] An energy storage device according to another aspect of the present invention for achieving the above object includes one or more of the above-described battery packs according to the present invention.

Effects of the Invention

[0035] According to one aspect of the present invention, a battery pack with improved safety can be provided.

[0036] In particular, according to one embodiment of the present invention, when a thermal event occurs inside the battery pack, the fire extinguishing agent (fire extinguishing liquid) supplied from the fire extinguishing tank flows into the empty space inside the blocking member through the opening at the upper end of the blocking member and stays in the space inside the blocking member, thereby effectively suppressing the propagation of the thermal event between the cells.

[0037] Also, when problems such as thermal runaway or ignition occur in some of the plurality of battery cells included in the battery pack, such problems can be effectively prevented from spreading to other battery packs.

[0038] Also, according to one aspect of the present invention, a battery pack with enhanced thermal safety can be provided while having a simple structure.

[0039] In particular, according to one embodiment of the present invention, since it is not necessary to add new components for injecting the fire extinguishing agent, a battery pack excellent in manufacturability and economy can be provided.

[0040] Also, according to one aspect of the present invention, it becomes unnecessary to design a special waterproof and dustproof structure, etc.

[0041] And, according to one aspect of the present invention, by stacking a plurality of battery packs of the same type, products with various voltages and / or storage capacities can be provided.

[0042] In addition, according to various embodiments of the present invention, various other additional effects can be achieved. Such various effects of the present invention will be described in detail in each embodiment, or the description will be omitted for effects that can be easily understood by those skilled in the art.

Brief Description of the Drawings

[0043] The following drawings attached to this specification illustrate preferred embodiments of the present invention and play a role in further understanding the technical idea of the present invention together with the detailed description of the invention to be described later. Therefore, the present invention should not be construed as being limited only to the matters described in the drawings.

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Embodiments for Carrying Out the Invention

[0044] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and the claims should not be construed as being limited to their ordinary or dictionary meanings, and based on the principle that the inventor can appropriately define the concept of the terms in order to explain his invention in the best way, they must be construed as meanings and concepts that conform to the technical idea of the present invention.

[0045] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention, so there may be various equivalents and modifications that can replace them at the time of this application.

[0046] To clearly explain the present invention, parts that are unnecessary for the explanation are omitted, and the same reference numerals are given to the same or similar components throughout the specification.

[0047] Also, the sizes and thicknesses of the respective configurations shown in the drawings are arbitrarily shown for the convenience of explanation, so the present invention is not necessarily limited to what is shown. In the drawings, the thickness is enlarged to clearly show a plurality of layers and regions. And in the drawings, for the convenience of explanation, the thicknesses of some layers and regions are exaggerated.

[0048] Also, when a part such as a layer, film, region, or plate is "above" another part, this includes not only the case where it is directly above the other part but also the case where there are other parts in between. Conversely, when a part is "directly above" another part, it means that there are no other parts in between. Also, being "above" the reference part means being located above or below the reference part, and it does not necessarily mean being located "above" in the direction opposite to gravity.

[0049] Also, throughout the specification, when a part "includes" a certain component, this means that, unless otherwise stated to the contrary, it does not exclude other components and can further include other components.

[0050] Also, throughout the specification, when it is said "on a plane", this means when the target part is viewed from above, and when it is said "in a cross-section", this means when the cross-section obtained by vertically cutting the target part is viewed from the side.

[0051] FIG. 1 is an exploded perspective view schematically showing the configuration of a battery pack according to an embodiment of the present invention. FIG. 2 is a perspective view schematically showing a part of the configuration of a battery pack according to an embodiment of the present invention, and FIG. 3 is a cross-sectional view of a battery pack according to an embodiment of the present invention. For example, it can be said that FIG. 3 shows an example of the cross-sectional configuration along line A1 - A1' in the state where the battery pack of FIG. 1 is combined.

[0052] Referring to FIGS. 1 to 3, the battery pack according to the present invention can include battery cells, a cutoff member 200, a pack case 300, and a fire extinguishing tank 400.

[0053] The battery cell 110 may mean a secondary battery. The secondary battery may include an electrode assembly, an electrolyte, and a battery case. In particular, the battery cell 110 may be a pouch-type secondary battery. However, other forms of secondary batteries, such as cylindrical batteries and prismatic batteries, may also be adopted as the battery cell 110 of the present invention. The battery pack according to the present invention may include a plurality of battery cells 110. Such a plurality of battery cells 110 may be stacked on one another in at least one direction. At this time, the plurality of battery cells 110 may be arranged side by side in a vertically standing form in the horizontal direction.

[0054] A plurality of secondary batteries may be stacked on one another, that is, a cell module assembly 100 may be formed with a battery cell stack. For example, a plurality of battery cells 110 may be stacked in a state where they are each vertically oriented (in the Z-axis direction of the drawing) and arranged horizontally (in the X-axis direction of the drawing). Each battery cell 110 may include an electrode lead, and such an electrode lead may be located at both ends or one end of each battery cell 110. A secondary battery with electrode leads protruding in both directions is called a two-way cell, and a secondary battery with electrode leads protruding in one direction is called a one-way cell. In FIG. 1, a two-way cell is illustrated. However, the present invention is not limited by such specific types and forms of secondary batteries, and various forms of secondary batteries known at the time of filing the present invention may be adopted in the cell module assembly 100 of the present invention.

[0055] The blocking member 200 may be configured to block heat by being interposed between adjacent battery cells 110. For example, when a thermal event occurs in some of the battery cells 110 and heat or high-temperature venting gas is generated in a state where a large number of battery cells 110 are stacked, the generated heat and gas can be suppressed or blocked from being transferred to adjacent battery cells 110 by the blocking member 200. In addition, the blocking member 200 can serve to block flames, sparks, etc. ejected from a specific battery cell 110.

[0056] The blocking member 200 can be configured in a substantially plate-like shape, particularly in the form of a standing plate. Further, the blocking member 200 can be configured to have a height similar to or higher than the height of the battery cells 110 arranged horizontally in a standing form. The blocking member 200 can be included in a large number according to the number of battery cells 110. And the blocking member 200 can form a cell module assembly (CMA) in a stacked form together with the battery cells 110.

[0057] According to such an implementation configuration of the present invention, in a battery pack including a large number of battery cells 110, heat runaway propagation between cells can be effectively prevented by the blocking member 200.

[0058] The pack case 300 can be configured to accommodate a large number of battery cells 110 and the blocking member 200 in its internal space. That is, an empty space is formed inside the pack case 300, and a cell module assembly that is a stacked body of the battery cells 110 and the blocking member 200 can be accommodated. The pack case 300 can be configured in the form of a box with an open upper end, but can also be configured in other various forms. Further, the pack case 300 can further include an upper cover coupled to the upper end opening. The pack case 300 in the form of a box may be integrally formed, or may be manufactured in a manner of coupling at least one surface to an adjacent surface.

[0059] The fire extinguishing tank 400 can hold a fire extinguishing agent. In particular, the fire extinguishing tank 400 has an internal space and can hold a fire extinguishing agent in the internal space. For example, as shown in FIG. 1, the fire extinguishing tank 400 can include a lower tank as a tank body (Coolant tank) and an upper cover as a tank cover (Coolant tank cover). Here, the tank body is configured in a box shape with an open top and can provide a space for holding a fire extinguishing agent. And the tank cover can be configured to cover the upper opening of the tank body and seal the fire extinguishing agent holding space of the tank body.

[0060] The fire extinguishing tank 400 can be housed inside the pack case 300. In particular, the fire extinguishing tank 400 can be arranged on the upper side of the cell module assembly in the internal space of the pack case 300.

[0061] According to such an implementation configuration of the present invention, when the fire extinguishing agent is discharged from the fire extinguishing tank 400 located on the upper side of the cell module assembly, the thermal event of the cell module assembly can be more easily controlled. In particular, the fire extinguishing agent discharged from the fire extinguishing tank 400 can easily move downward by gravity. Therefore, the heat and fire of the cell module assembly can be more easily suppressed by the fire extinguishing agent.

[0062] In particular, when the cell module assembly includes a plurality of battery cells 110 arranged side by side in the horizontal direction, that is, the left - right direction, as shown in FIG. 1, when the fire extinguishing agent is discharged from the fire extinguishing tank 400 located on the upper part, the fire extinguishing agent can be easily supplied to the entire battery cell 110. Therefore, according to such an implementation configuration, the suppression of the thermal event for the entire cell module assembly can be carried out more effectively.

[0063] As shown in FIG. 3, the blocking member 200 can be configured in a form in which a heat insulating material is interposed between metal plates.

[0064] Here, the metal plate can be made of an aluminum material. That is, the metal plate can be an aluminum plate.

[0065] Also, the heat insulating material can be a mica sheet or a compression paper (plate).

[0066] According to such an implementation configuration, the blocking member 200 plays the roles of thermal spread and cooling, and the heat / flame blocking effect between cells can be further improved.

[0067] Also, when heat is applied to the fire extinguishing tank 400 from the cell assembly, the fire extinguishing tank 400 can be configured to discharge a fire extinguishing agent to the cell assembly side. In particular, the fire extinguishing tank 400 can be configured such that at least a part thereof is melted by the heat applied from the cell assembly. Also, the fire extinguishing tank 400 can be configured to be melted by the venting gas ejected from the battery cell 110 or the temperature of the battery cell 110.

[0068] Also, the fire extinguishing tank 400 can hold a fire extinguishing agent in a liquid state. For example, the fire extinguishing tank 400 can hold water, salt water, cooling water, insulating oil, etc. as the fire extinguishing agent.

[0069] Also, the fire extinguishing tank 400 can be configured such that the thickness of the base plate has a difference depending on the position. Also, the fire extinguishing tank 400 can be located at the central portion between cells where fragile portions having a relatively thin thickness are laminated horizontally with each other.

[0070] FIG. 4 is an exploded perspective view schematically showing the configuration of a battery pack according to another embodiment of the present invention. FIG. 5 is a cross-sectional view showing the configuration of a fire extinguishing tank included in the battery pack of FIG. 4, and FIG. 6 is a top view showing the configuration of the fire extinguishing tank included in the battery pack of FIG. 4. FIGS. 7 and 8 are a perspective view and a top view showing the configuration of a cell module assembly included in the battery pack of FIG. 4. FIGS. 9 and 10 are cross-sectional views of a battery pack according to another embodiment of the present invention.

[0071] Referring to FIGS. 4 to 10, a fire extinguishing tank 400 can be disposed above a cell module assembly including a battery cell 110 and a blocking member 200. In particular, as shown in FIG. 8, the blocking member 200 can include an insulating pad and a swelling pad.

[0072] Also, as shown in FIG. 9, the upper fire extinguishing tank 400 and the battery cell 110 can be positioned so as to be orthogonal to each other. Therefore, even if an event such as venting gas or a spark occurs in any part of the battery cell 110, a fire extinguishing agent (e.g., coolant) can be easily introduced.

[0073] Also, the blocking member 200 can be configured such that the fire extinguishing agent discharged from the fire extinguishing tank 400 can flow in. For example, when water is discharged from the fire extinguishing tank 400, the discharged water can be configured to flow into the inside of the blocking member 200. At this time, the blocking member 200 can have a space for injecting a fire extinguishing liquid therein or can include a substance capable of absorbing the fire extinguishing liquid. Also, the blocking member 200 can be configured in various forms into which the fire extinguishing liquid can flow.

[0074] For example, as shown in FIG. 10, the blocking member 200 can be configured such that when an event occurs, the upper fire extinguishing agent (e.g., coolant) fills the voids of the insulating pad and the heat insulation performance is maximized.

[0075] According to such an embodiment of the present invention, the effect of preventing the propagation of heat / flame between cells by the blocking member 200 can be further increased.

[0076] FIG. 11 is an exploded perspective view schematically showing the configuration of a battery pack according to another embodiment of the present invention.

[0077] Referring to FIG. 11, the battery pack includes a cell module assembly 100, a blocking member 200, a pack case 300, a fire extinguishing tank 400, an external cover 500, and an electrical connection unit 600.

[0078] In FIG. 11 too, the cell module assembly 100 can be stacked in a form in which a plurality of battery cells 110 are arranged along the horizontal direction (for example, the X-axis direction in the drawing) with each standing in the vertical direction (for example, the Z-axis direction in the drawing). At this time, the length direction of the battery cell 110 is, for example, the Y-axis direction in the drawing.

[0079] FIG. 12 is a perspective view of a cell module assembly 100 included in the battery pack of FIG. 11.

[0080] For reference, in order to more clearly show the components included in the cell module assembly 100, FIG. 12 shows the remaining components excluding the plurality of battery cells 110. The plurality of battery cells 110 can be ordinary pouch-type battery cells or prismatic battery cells.

[0081] Referring to FIG. 12, a pair of bus bar housings 130 are arranged on the front and rear surfaces of the stack of the plurality of battery cells 110. Each of the bus bar housings 130 is arranged in a direction orthogonal to the length direction of the battery cell 110 (for example, the X-axis direction in the drawing).

[0082] A pair of end plates 120 are respectively provided at the outermost both ends of the stack of the plurality of battery cells 110. The end plates 120 are arranged parallel to the battery cells 110. The pair of end plates 120 are respectively connected between the pair of bus bar housings 130.

[0083] At least one strap 140 connecting between the pair of end plates 120 can be included on each of the upper side and the lower side between the pair of end plates 120. The strap 140 strengthens the binding of the cell module assembly 100. More specifically, it strengthens the binding of the pair of end plates 120 and the stack of a plurality of battery cells 110 disposed therebetween. Thereby, it is possible to prevent the alignment of the stack of a plurality of battery cells 110 from being displaced.

[0084] Since the description of the cell module assembly 100 overlaps with that described in FIG. 1, refer to what has been described above in relation to FIG. 1.

[0085] On the other hand, as shown in FIG. 11, a plurality of battery cells 110 can be grouped and stored in a predetermined number. Also, as shown in FIGS. 11 to 17, a blocking member 200 is provided between a group of a plurality (predetermined number) of battery cells 110 and a group of a plurality (predetermined number) of battery cells 110 adjacent to the group.

[0086] FIG. 13 is a perspective view of the blocking member 200 included in the battery pack of FIG. 11. FIG. 14 is an exploded perspective view of the blocking member 200 of FIG. 13. FIG. 15 is a top view of the blocking member 200 of FIG. 13. FIGS. 16 and 17 show cross-sectional views of modified examples of the blocking member 200 of FIG. 13, respectively. The cross-sectional views are cross-sectional views along the line A3 - A3' of FIG. 15.

[0087] The blocking member 200 can be configured to block heat by being interposed between adjacent battery cells 110. For example, when a thermal event occurs in some of the battery cells 110 and heat or hot venting gas is generated, the generated heat or gas can be suppressed or blocked from being transferred to adjacent battery cells 110 by the blocking member 200. Also, the blocking member 200 can serve to block flames, sparks, etc. ejected from a specific battery cell 110.

[0088] The blocking member 200 has a substantially plate-like shape. The blocking member 200 can be configured in the form of a plate standing in the vertical direction. Further, the blocking member 200 can have the same or a similar height as that of the battery cell 110 standing in the vertical direction. The height of the blocking member 200 may be lower or higher than the height of the battery cell 110.

[0089] A plurality of blocking members 200 may be included depending on the number of battery cells. And, as described above, the blocking member 200 can form the cell module assembly 100 in a stacked form together with the battery cell 110.

[0090] According to such an embodiment configuration of the present invention, in a battery pack including a plurality of battery cells 110, the blocking member 200 can effectively prevent the propagation of thermal runaway between cells and the like.

[0091] Further, the blocking member 200 can generally consist of a triple structure. For example, a pair of swelling pads 220 are provided on both sides of the support plate 210. The support plate 210 maintains the form and rigidity of the blocking member 200 and blocks flames, sparks, etc. ejected from the battery cell 110 between the battery cells 110. The support plate 210 can be made of, for example, a metal or stainless steel material. The swelling pad 220 reduces the pressure applied to the battery cell 110 by the support plate 210 when the battery cell 110 expands. The swelling pad 220 can be made of, for example, a silicone material or a soft plastic material.

[0092] The length of the swelling pad 220 may be smaller than or the same as the length of the support plate 210. Here, the length means, for example, the Y-axis direction in the drawing.

[0093] On the one hand, the blocking member 200 according to the present invention includes a plurality of openings 231 at its upper end. Further, inside the blocking member 200, there is an empty space connected to the plurality of openings 231. When a fire extinguishing agent (fire extinguishing liquid) is introduced from the fire extinguishing tank 400 located above the cell module assembly 100 into the cell module assembly 100, the fire extinguishing agent (fire extinguishing liquid) enters the empty space inside the blocking member 200 through the plurality of openings 231. That is, by allowing the fire extinguishing agent (fire extinguishing liquid) to stay in the empty space inside the blocking member 200, the battery cell 110 where a thermal event has occurred can be more effectively cooled and extinguished.

[0094] Further, the blocking member 200 includes a plurality of through-holes 230 arranged in one direction.

[0095] In the embodiment according to FIGS. 13 to 17, as shown in detail in FIGS. 14 and 15, the support plate 210 includes a plurality of through-holes 230 formed to penetrate the support plate 210 in the vertical direction, that is, the height direction (for example, the Z-axis direction of the drawing). The plurality of through-holes 230 are arranged along the length direction of the support plate 210 (for example, the Y-axis direction of the drawing). That is, the uppermost ends of the plurality of through-holes 230 become the plurality of openings 231. The inside of the plurality of through-holes 230 becomes the empty space inside the blocking member 200.

[0096] When a fire extinguishing agent (fire extinguishing liquid) is introduced from the fire extinguishing tank 400 located above the cell module assembly 100 into the cell module assembly 100, the fire extinguishing agent (fire extinguishing liquid) also enters the plurality of through-holes 230. That is, by allowing the fire extinguishing agent (fire extinguishing liquid) to stay in the plurality of through-holes 230, the battery cell 110 where a thermal event has occurred can be more effectively cooled and extinguished.

[0097] As shown in FIG. 14, a plurality of through holes 230 may be in a form that is open on both sides of the upper and lower surfaces of the support plate 210. Alternatively, as shown in FIG. 16, a plurality of through holes 230 may have a shape in which only the upper surface is open and the lower surface is closed so that the fire extinguishing agent (fire extinguishing liquid) can stay longer in the through holes 230. When assembling the battery pack, if the support plate 210 of the blocking member 200 is arranged to be in close contact with or adhered to the inner lower surface of the pack case 300 in the former case, the fire extinguishing agent (fire extinguishing liquid) can stay longer in the through holes 230 as in the latter case.

[0098] On the other hand, when manufacturing the blocking member 200, as shown in the left drawing of FIG. 14, the support plate 210 can also be manufactured by a method of combining a pair of support plate members 210-1 and 210-2. At this time, the pair of support plate members 210-1 and 210-2 are combined with a pair of support plate members 210-1 and 210-2 formed symmetrically about the cross section in the length direction of the support plate 210. Alternatively, as shown in the right drawing of FIG. 14, the support plate 210 can be manufactured by integrally molding it from the beginning.

[0099] As shown in the left drawing of FIG. 14, when manufacturing and combining a pair of support plate members 210-1 and 210-2, the forming of a plurality of through holes 230 can be facilitated. In order to make the connection of the pair of support plate members 210-1 and 210-2 more firm, a support plate fastening member 211 can be further included. The support plate fastening member 211 can include a female support plate fastening member 211a and a male support plate fastening member 211b. However, the present invention is not limited to what is shown, and any shape capable of connecting the pair of support plate members 210-1 and 210-2 is sufficient.

[0100] FIG. 17 shows a case where a plurality of through holes 230 are not formed in only one direction, but are formed in two directions respectively and intersect.

[0101] For example, as an embodiment shown in FIG. 17, a case where a plurality of first through holes 230a extending in a first direction and a plurality of second through holes 230b extending in a second direction intersect orthogonally is shown. The plurality of first through holes 230a are formed in a first direction (vertical direction, that is, height direction (for example, Z-axis direction in the drawing)) of the support plate 210. The plurality of second through holes 230b are formed in a second direction (length direction (for example, Y-axis direction in the drawing)) of the support plate 210. When a thermal event of the battery cell 110 occurs, the fire extinguishing agent (fire extinguishing liquid) introduced from the fire extinguishing tank 400 flows into the plurality of first through holes 230a of the support plate 210, and subsequently also flows into the plurality of second through holes 230b intersecting therewith.

[0102] The plurality of second through holes 230b may not penetrate to both side surfaces of the support plate 210. That is, both ends of the plurality of second through holes 230b are formed at a predetermined distance from both side surfaces of the support plate 210, and both ends of the plurality of second through holes 230b may be closed. Thereby, the fire extinguishing agent (fire extinguishing liquid) flowing into the plurality of second through holes 230b can stay in the through hole 230 without leaking out to both side surfaces of the support plate 210. Alternatively, the plurality of second through holes 230b may penetrate to both side surfaces of the support plate 210. The both side surfaces of the support plate 210 can also be assembled so as to be in close contact with or adhered to the bus bar housing 130 shown in FIG. 12 so that the fire extinguishing agent (fire extinguishing liquid) flowing into the plurality of second through holes 230b does not leak out to both side surfaces of the support plate 210.

[0103] Modifying FIG. 17, for example, a case where a plurality of first through holes 230a extending in a first direction and a plurality of second through holes 230b extending in a second direction intersect orthogonally, and each of the plurality of first through holes 230a and the plurality of second through holes 230b extends in an oblique direction of the support plate 210 (for example, an angle inclined 45 degrees with reference to the upper end of the blocking member 400) can also be implemented.

[0104] On the one hand, the present invention is not limited to what is shown in the drawings. For example, various modifications and changes are possible, such as when a plurality of through-holes 230 are formed in three directions and intersect each other.

[0105] To summarize, the blocking member 200 according to the present invention commonly has an opening at the upper end of the blocking member 200. When a thermal event occurs in the battery cell 110, the fire extinguishing agent (fire extinguishing liquid) in the fire extinguishing tank 400 located above the cell module assembly 100 flows into the plurality of through-holes 230 through the opening located at the uppermost end of the blocking member 200, so that it can stay longer in the internal space of the support plate 210. As a result, the fire extinguishing agent (fire extinguishing liquid) can stay longer between the battery cells 110, enabling more effective cooling or fire extinguishing of the battery cells 110.

[0106] FIG. 18 is a perspective view of the pack case 300 included in the battery pack of FIG. 11. FIG. 19 is a drawing for explaining the case where the cell module assembly 100 of FIG. 18 is housed in the pack case 300.

[0107] Referring to FIG. 18, the pack case 300 can be configured in a box form. The box-shaped pack case 300 may be integrally formed or may be manufactured by a method of coupling at least one surface to an adjacent surface.

[0108] The pack case 300 includes at least one venting port 320. A filter is attached to the venting port 320.

[0109] When a thermal event occurs in the battery cell 110 housed inside the pack case 300, the venting gas generated in the battery cell 110 can be discharged through the venting port 320. The venting gas discharged at the venting port 320 can pass through the space between the pack case 300 and the external cover 500 (see FIG. 11) and be discharged to the outside of the external cover 500.

[0110] On the one hand, as shown in FIGS. 19 and 20, after the cell module assembly 100 shown in FIG. 12 is housed in the internal space of the auxiliary case 310, it can also be mounted on the pack case 300. After the cell module assembly 100 is primarily housed in the internal space of the auxiliary case 310 and finally housed in the pack case 300, the rigidity of the cell module assembly 100 can be complemented, and misalignment of the plurality of battery cell 110 stacks in the cell module assembly 100 can be prevented. The auxiliary case 310 can be made of, for example, metal or stainless steel.

[0111] FIG. 21 is a perspective view of the fire extinguishing tank 400 included in the battery pack of FIG. 11. FIG. 22 is a perspective sectional view of the fire extinguishing tank 400 of FIG. 21, showing a section along the line A2 - A2' of FIG. 11. FIG. 23 is an upper sectional view of the lower tank 410 of the fire extinguishing tank 400 viewed from above.

[0112] As described above with reference to FIG. 1, the fire extinguishing tank 400 includes a lower tank 410 and an upper cover 420. The lower tank 410 and the upper cover 420 may be separately manufactured and hermetically joined, or may be integrally manufactured. The upper cover 420 can additionally include an injection port 430 through which a fire extinguishing agent can be injected. The injection port 430 can be closed with a cap to seal the fire extinguishing tank 400.

[0113] The portion formed with a thin thickness on the base plate 411 of the lower tank 410 can function as a vulnerable part 411a. That is, when a thermal event occurs in the battery cell 110 of the cell module assembly 100, such a relatively thin vulnerable part 411a can be damaged first. When the vulnerable part 411a is damaged and an opening is formed in the base plate 411, the fire extinguishing agent held inside the fire extinguishing tank 400 can be discharged to the cell module assembly 100 side through the vulnerable part 411a.

[0114] A plurality of weak portions 411a may be provided. The weak portion 411a may, for example, have a narrow width and a long length. That is, it may be linear and may be in a linear shape arranged parallel to one edge of the fire extinguishing tank 400, and the respective weak portions 411a may be arranged parallel to each other.

[0115] On the other hand, according to the present embodiment, the length direction of the battery cell 110 (for example, the Y-axis direction in the drawing) and the length direction of the weak portion 411a (for example, the X-axis direction in the drawing) can be orthogonal to each other. That is, a plurality of weak portions 411a are arranged to intersect the length direction of the battery cell 110. Thereby, along the length direction of the battery cell 110 in which a thermal event has occurred, the fire extinguishing agent can be supplied all at once through the plurality of open weak portions 411a over the entire battery cell 110, and the battery cell 110 in which the thermal event has occurred can be extinguished more efficiently and quickly.

[0116] Also, referring to FIG. 22, the base plate 411 of the lower tank 410 has a step. More specifically, the base plate 411 is roughly divided as follows. It includes a portion A7 where the weak portion 411a is located, a portion A8 that abuts on the strap 140 of the pack case 100, and a portion A9 located on the side of the electrical connection unit 600. Among these, the height of the base plate 411 of the portion A7 where the weak portion 411a is located is the lowest.

[0117] By arranging the weak portion 411a of the lower tank 410 as adjacent as possible to the battery cell 110, when an overheat or ignition situation occurs in some of the battery cells 110, through rapid initial suppression, the occurrence of dangerous situations such as a secondary explosion due to the transfer of heat or flame to the adjacent battery cell 100 can be more effectively prevented.

[0118] For additional explanation, as shown in FIG. 12 regarding the cell module assembly 100, the height of the cell module assembly 100 is not constant due to the portion where the strap 140 is located, the portion where the bus bar housing 130 is located, etc. Regardless of this, if the height of the base plate 411 of the lower tank 410 of the fire extinguishing tank 400 is overall constant, a space will relatively be created between the base plate 411 of the fire extinguishing tank 400 and the upper surface of the cell module assembly 100. In such a case, the space will cause an obstruction to the heat transfer from the battery cell 110 with an increased temperature to the vulnerable part 411a, and the fire extinguishing will be delayed accordingly.

[0119] When the battery cell 110 overheats, by arranging the vulnerable part 411a to be immediately adjacent to the battery cell 110 with the increased temperature, the vulnerable part 411a can be damaged immediately and the battery cell 110 can be quickly cooled and fire extinguished.

[0120] To summarize, the lower surface of the base plate 411 of the fire extinguishing tank 400 and the upper surface of the cell module assembly 100 have substantially the same shape. As a result, the fire extinguishing tank 400 is arranged to be more closely attached to the cell module assembly 100, so that the battery cell 110 with a temperature rise can be cooled more effectively, and the fire extinguishing agent can be more quickly injected into the battery cell 110 with overheating or ignition. Also, more fire extinguishing agent can be efficiently stored in the fire extinguishing tank 400. That is, if the height of the base plate 411 of the lower tank 410 of the fire extinguishing tank 400 is overall constant, the fire extinguishing tank 400 will store less fire extinguishing agent by the amount of the empty space.

[0121] The fire extinguishing agent provided in the fire extinguishing tank 400 may be in the form of, for example, a fire extinguishing liquid. Duplicate explanations are omitted, and reference is made to what has been described above.

[0122] FIG. 24 is a perspective view of the battery pack in which all the components of the aforementioned battery pack are combined with reference to FIGS. 11 to 23.

[0123] In addition, for the parts where the descriptions of the battery packs in FIGS. 11 to 24 overlap with the parts described in relation to the battery packs in FIGS. 1 to 10, refer to those described in FIGS. 1 to 10.

[0124] On the other hand, a plurality of the pack cases 300 may be provided and configured to be stackable in the vertical direction. This will be described more specifically with reference to FIG. 25.

[0125] FIG. 25 is a perspective view schematically showing at least a part of the configuration of the battery packs in FIGS. 1 to 24 of the present invention. FIGS. 26 and 27 are drawings showing an embodiment in which a plurality of the pack cases 300 shown in FIG. 25 are stacked.

[0126] Referring to FIG. 25, the pack case 300 may include a bottom portion and a side wall portion. In the internal space of such a pack case 300, the cell module assembly 100 may be housed, and the battery pack is configured by covering the upper surface of the cell module assembly 100 with the fire extinguishing tank 400. For reference, in FIG. 25, the height of the upper side of the pack case 300 is shown to be higher than the height of the upper surface of the fire extinguishing tank 400. However, FIG. 25 is a schematic view and is only one embodiment, and the present invention is not limited to that shown in FIG. 25. That is, conversely, the height of the upper surface of the fire extinguishing tank 400 may be higher than the height of the upper side of the pack case 300, or the height of the upper surface of the fire extinguishing tank 400 and the height of the upper side of the pack case 300 may be the same, and various modifications and changes are possible.

[0127] A plurality of pack cases 300 as shown in FIG. 25 may be provided, and a stacked structure of the battery packs may be formed as shown in FIG. 26 or FIG. 27. At this time, the battery pack in FIG. 25 may be one unit pack. And by providing a plurality of such unit packs, a module stacked type overall battery pack as shown in FIGS. 26 and 27 may be configured.

[0128] More specifically, for example, in the configuration of FIG. 26, a form in which three unit packs D are stacked in the vertical direction is shown. And in the configuration of FIG. 27, a form in which five unit packs D are stacked in the vertical direction is shown. The present invention is not limited to what is illustrated, and the number of unit packs D can be variously changed and implemented according to the environment in which the present invention is embodied.

[0129] For example, when the battery pack of the present invention is implemented as an energy storage system (ESS), by adjusting the number of unit battery packs, the voltage and / or the power storage capacity of the energy storage device can be implemented to suit the environment.

[0130] According to such an implementation configuration of the present invention, one unit pack having a common structure can be variously stacked, and products with various voltages and / or power storage capacities can be supported according to the stacking number. For example, by adjusting the stacking number of the same unit packs, it is possible to implement products in a low voltage range as shown in FIG. 26 and products in a high voltage range as shown in FIG. 27. Therefore, compared with products limited only to a specific voltage standard, economic efficiency, compatibility, etc. can be improved. Also, with such an implementation configuration, products with various capacities can be implemented according to the stacking number.

[0131] In other words, when connected in series between the stacked unit packs, products with various voltages can be implemented according to the stacking number. Also, when connected in parallel between the stacked unit packs, products with various capacities (power storage capacities) can be implemented according to various stacking numbers.

[0132] In particular, each unit pack D can include a cell module assembly 100 inside. Also, as described above, each unit pack D includes a connector 610 so that the respective cell module assemblies 100 can be electrically connected to each other during stacking. In particular, such a connector 610 can be configured to be coupled to each other by vertical stacking of each unit pack D.

[0133] Also, in the above-described implementation configuration, a fire extinguishing tank 400 can be stored together with the cell module assembly 100 in each unit pack D. That is, as described above, each unit pack D includes the fire extinguishing tank 400 above the cell module assembly 100. The plurality of stacked battery packs have a stacked structure of fire extinguishing tank 400 - cell module assembly 100 - fire extinguishing tank 400 - cell module assembly 100 from top to bottom. The stacked battery pack of the present invention having such a structure can configure the battery pack by increasing (expanding) the number of cell module assemblies 100 to increase the power storage capacity, while also being safely prepared for thermal events such as a fire in the cell module assembly 100. Therefore, according to such an implementation configuration of the present invention, the safety of the battery pack can be further improved.

[0134] As another example of the coupling method between the battery packs (pack cases) 300 stacked vertically, referring to FIG. 25 again, it is as follows. At the upper end of the side wall portion of the pack case 300, there can be a step formed in a concave shape in the inner direction, such as the coupling step portion C1. For example, it is a thin portion of the side wall portion of the pack case 300. Also, although not shown in FIG. 25, a coupling recess can be formed at the bottom of the pack case 300 so that such a coupling step portion C1 of the side wall portion can be inserted. That is, when stacking the different pack cases 300 vertically, the coupling step portion C1 formed at the upper end of the side wall portion of the lower-layer pack case 300 can be configured to be inserted into the coupling recess formed at the bottom of the upper-layer pack case 300. Thereby, when a plurality of pack cases 300 are stacked and coupled in the vertical direction, the outer surface of the pack case 300 can have an overall flat shape.

[0135] On the other hand, the coupling method regarding the fastening structure between the battery packs stacked vertically is not limited to those shown in FIG. 25 and / or FIG. 18, and other various coupling methods can be modified and applied to the present invention.

[0136] Also, the battery pack of the present invention can be connected to a battery management system (BMS, not shown). The battery management system monitors and manages the battery pack(s). The battery management system can be located at the uppermost layer of the battery packs stacked vertically. However, the position of the battery management system is not limited to the above-described one, and can be variously modified and changed according to the manner and environment in which the present invention is implemented.

[0137] In addition to the foregoing components, the battery pack according to the present invention can further include various other components included in the battery pack. For example, the battery pack according to the present invention can include many electrical components for controlling or managing the charge and discharge of the battery pack, such as a battery management system (BMS), relays, fuses, current sensors, etc.

[0138] The battery pack according to the present invention can be a residential battery pack. However, the present invention is not necessarily limited to such a battery pack form.

[0139] The energy storage system according to the present invention includes one or more of the battery packs according to the present invention described above. In addition to such battery packs, the energy storage system according to the present invention can further include general components included in the energy storage system.

[0140] On the other hand, in this specification, terms indicating directions such as up, down, left, and right may be used, but such terms are merely for convenience of explanation and it is obvious to those skilled in the art of the present invention that they can vary depending on the position of the object and the position of the observer, etc.

[0141] As described above, the present invention has been described with reference to limited embodiments and drawings, but the present invention is not limited thereby, and it goes without saying that various modifications and variations are possible within the scope equivalent to the technical idea of the present invention and the scope of the claims described below by those having ordinary knowledge in the technical field to which the present invention pertains.

Description of Reference Numerals

[0142] 110: Cell module assembly 110: Battery cell 120: End plate 130: Bus bar housing 140: Strap 200: Shut-off member 210: Support plate 210-1, 210-2: Pair of support plate members 220: Swelling pad 230: Through hole 230a: First through hole 230b: Second through hole 300: Pack case 310: Auxiliary case 320: Venting port 400: Fire extinguishing tank 410: Lower tank 411: Base plate 411a: Weak part 420: Upper cover 430: Injection port 500: Outer cover 600: Electrical connection unit 610: Connector

Claims

1. A cell module assembly including a battery cell stack in which a plurality of battery cells are aligned and stacked; A plate-shaped blocking member disposed between the battery cells adjacent to each other; A pack case having a shape with an open side for housing the cell module assembly; and A fire extinguishing tank located above the cell module assembly, covering the open side of the pack case, and containing a fire extinguishing agent, The battery pack, wherein the blocking member includes a plurality of openings at one end facing the fire extinguishing tank, and the inside of the blocking member includes an empty space connected to the plurality of openings.

2. The battery pack according to claim 1, wherein when a thermal event of the battery cell occurs, the fire extinguishing agent contained in the fire extinguishing tank flows into the empty space inside the blocking member through the plurality of openings of the blocking member.

3. The battery pack according to claim 1, wherein the blocking member includes a support plate and a pair of swelling pads provided on both sides of the support plate.

4. The support plate includes a plurality of first through holes formed by penetrating the support plate in one direction from the plurality of openings, The battery pack according to claim 3, wherein the inside of the plurality of first through holes is the empty space inside the blocking member.

5. The battery pack according to claim 4, wherein the first through holes extend in a direction from the fire extinguishing tank toward the cell module assembly, and each of the plurality of first through holes is arranged in a row parallel to each other.

6. So that the fire extinguishing agent can stay inside the plurality of first through holes, One end of the plurality of first through-holes, which is located on the side away from the fire extinguishing tank, is opened at one end of the support plate located on the side away from the fire extinguishing tank, and one end of the support plate is arranged to be in close contact with or adhered to the side portion of the pack case opposite to the one side portion, or One end of the plurality of first through-holes has a closed shape, and the battery pack according to claim 4.

7. The support plate further includes a plurality of second through-holes, The plurality of first through-holes and the plurality of second through-holes extend in different directions and intersect each other, The interiors of the plurality of first through-holes and the plurality of second through-holes are the empty spaces inside the blocking member, and the battery pack according to claim 4.

8. Both ends of the plurality of second through-holes have closed shapes respectively, and the battery pack according to claim 6.

9. The first through-hole extends in a direction from the fire extinguishing tank toward the cell module assembly, and each of the plurality of first through-holes is arranged in a row parallel to each other, The second through-hole extends orthogonally to the first through-hole, and each of the plurality of second through-holes is arranged in a row parallel to each other, and the battery pack according to claim 7.

10. The support plate is made of a metal material, The swelling pad is made of a silicone or soft plastic material, and the battery pack according to claim 3.

11. The support plate is formed by joining a pair of support plate members symmetrically formed about a cross-section in the length direction of the support plate, and the battery pack according to claim 3.

12. The support plate is integrally formed, and the battery pack according to claim 3.

13. The fire extinguishing agent is a fire extinguishing agent in a liquid state, the battery pack according to claim 1.

14. The fire extinguishing tank is: A portion where the thickness of the base plate of the fire extinguishing tank is relatively thin, including a plurality of vulnerable parts that are melted and opened by a thermal event of the battery cell, the battery pack according to claim 1.

15. The vulnerable part is linear and arranged parallel to one edge of the fire extinguishing tank, The length direction of the vulnerable part and the length direction of the battery cell are orthogonal to each other, the battery pack according to claim 14.

16. The cell module assembly is: A pair of bus bar housings arranged on the front and rear surfaces of the stack of battery cells; and Including a pair of end plates arranged parallel to the battery cells at both side ends of the stack of battery cells, The pair of end plates connect between the pair of bus bar housings, the battery pack according to claim 1.

17. The battery pack is provided in a plurality and can be stacked in a direction from the fire extinguishing tank toward the cell module assembly, The stacked battery packs are coupled to each other by mechanical connection and electrical connection, the battery pack according to claim 1.

18. An energy storage system including the battery pack according to any one of claims 1 to 17.

19. The fire extinguishing agent is a coolant, the battery pack according to claim 1.

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