Battery pack with heat propagation delay structure

Abstract

To provide a battery pack capable of effectively suppressing and preventing a heat propagation phenomenon in which heat transfer due to thermal runaway occurring in a certain secondary battery in the battery pack is diffused to other peripheral secondary batteries or battery modules.SOLUTION: The disclosed invention relates to a pack case, and in one example, the pack case includes a cooling plate having a cooling passage therein, a side plate coupled to an edge of the cooling plate to form a sidewall, a center frame coupled to the cooling plate to vertically divide a receiving space formed by the side plate, and a side beam coupled to the cooling plate to laterally divide a plurality of spaces divided by the center frame. The cooling plate may include a slot formed along a coupling position of the center frame and / or the side beam.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a battery pack capable of retarding heat transfer between battery modules housed in the battery pack.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0113165, dated September 7, 2022, and all contents disclosed in the documents of this Korean patent application are incorporated herein by reference. [Background technology]

[0003] Unlike primary batteries, secondary batteries are rechargeable and have the potential to be small and have large capacities, which has led to extensive research and development of secondary batteries in recent years. Demand for secondary batteries as an energy source is rapidly increasing due to the increasing technological development and demand for mobile devices, as well as the emergence of electric vehicles and energy storage systems in response to modern demands for environmental protection.

[0004] Secondary batteries are classified into coin-type batteries, cylindrical batteries, prismatic batteries, and pouch-type batteries depending on the shape of the battery case. The electrode assembly installed inside the battery case of a secondary battery is a power generating element that can be charged and discharged and is made up of a laminated structure of electrodes and a separator.

[0005] Since secondary batteries are required to be used continuously for long periods of time, it is necessary to effectively control the heat generated during the charging and discharging process.If secondary batteries are not cooled smoothly, a positive feedback chain reaction will occur in which a rise in temperature causes an increase in current, and the increase in current causes another rise in temperature, resulting in a catastrophic state of thermal runaway.

[0006] In addition, when secondary batteries are grouped together in the form of a module or pack, thermal runaway in one secondary battery can cause thermal propagation, in which other surrounding secondary batteries are continuously overheated. Furthermore, there is a high risk of fire due to ignition sources such as flammable gases emitted from an overheated secondary battery and heating electrodes, so it is necessary to prevent such fire risks. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Korean Patent Publication No. 2022-0017741 (Published February 14, 2022) Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a battery pack that can effectively suppress and prevent a heat propagation phenomenon in which heat transfer due to thermal runaway occurring in a secondary battery in the battery pack spreads to other surrounding secondary batteries or battery modules.

[0009] However, the technical problems that the present invention aims to solve are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention described below. [Means for solving the problem]

[0010] The present invention relates to a pack case, which in one example includes a cooling plate having a cooling channel therein, side plates coupled to the edges of the cooling plate to form side walls, a center frame coupled to the cooling plate to vertically divide the storage space formed by the side plates, and side beams coupled to the cooling plate to horizontally divide the multiple spaces divided by the center frame, wherein the cooling plate has slots formed therethrough along the coupling positions of the center frame and / or the side beams.

[0011] In one embodiment of the present invention, a plurality of the slots are provided, and the plurality of slots are spaced apart along the joining position of the center frame or the side beam.

[0012] The slots may be formed to a size that prevents them from being exposed to the outside of the center frame and side beams.

[0013] The spaced apart slots define fastening points for the center frame or side beams.

[0014] Here, the fastening points can be distributed at both ends and in between of a row of slots.

[0015] The cooling plate may have cooling channels and slots that do not overlap or intersect with each other.

[0016] In one embodiment of the present invention, the space formed by the slot may be filled with a heat insulating material, and the heat insulating material may be a watertight material.

[0017] The cooling device may further include a base plate coupled to the bottom surface of the cooling plate.

[0018] The base plate may include base slots that correspond to slots formed in the cooling plate.

[0019] Meanwhile, the present invention provides a battery pack including the pack case, and battery modules accommodated in respective storage spaces divided vertically and horizontally by a center frame and side beams of the pack case.

[0020] In the battery pack of the present invention, conductive heat transfer through the cooling plate between the battery modules with the center frame or side beams interposed therebetween is delayed by the slots.

[0021] A thermal resin layer may be interposed on the contact surface between the battery module and the cooling plate, and it is preferable that the thermal resin layer does not intrude into the slot. [Effects of the Invention]

[0022] In the pack case and battery pack of the present invention having the above-described configuration, a portion of the heat conduction path between the battery modules via the cooling plate is eliminated by the through slot, thereby suppressing and delaying excessive heat transfer caused by a battery module experiencing thermal runaway, thereby improving the safety of the battery pack.

[0023] However, the technical effects that can be obtained by the present invention are not limited to the effects described above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the invention described below. [Brief explanation of the drawings]

[0024] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention described below, serve to further understand the technical concept of the present invention, and therefore the present invention should not be interpreted as being limited solely to the matters depicted in such drawings. [Figure 1] 1 is a diagram illustrating the overall configuration of a pack case according to the present invention. [Figure 2]FIG. 2 is an exploded perspective view of the pack case according to the present invention. [Figure 3] 1 is a diagram illustrating a cooling plate. [Figure 4] 1 is a view illustrating a battery pack according to the present invention; [Figure 5] 5 is a diagram illustrating another embodiment of the battery pack of FIG. 4. [Figure 6] FIG. 5 is a cross-sectional view illustrating another embodiment of the battery pack of FIG. 4. [Figure 7] 10 is a view illustrating a heat transfer delay structure using slots formed in a cooling plate; DETAILED DESCRIPTION OF THE INVENTION

[0025] Because the present invention can be modified in various ways and can have various embodiments, specific embodiments will be described in detail below.

[0026] However, this is not intended to limit the invention to any particular embodiment, but should be understood to include all modifications, equivalents, or alternatives falling within the spirit and scope of the invention.

[0027] In the present invention, the terms "comprise" and "have" are intended to specify the presence of features, numbers, steps, operations, components, parts or combinations thereof described in the specification, and should be understood as not precluding the presence or possibility of addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0028] Furthermore, in the present invention, when a layer, film, region, plate, or other portion is described as being "on" another portion, this includes not only the case where it is "directly on" the other portion, but also the case where there is another portion therebetween. Conversely, when a layer, film, region, plate, or other portion is described as being "under" the other portion, this includes not only the case where it is "directly under" the other portion, but also the case where there is another portion therebetween. Furthermore, in this application, being "located on" can include not only the case where it is located at the top, but also the case where it is located at the bottom.

[0029] The present invention relates to a pack case capable of mounting a plurality of battery modules. In one example, the pack case includes a cooling plate having a cooling channel therein, side plates coupled to edges of the cooling plate to form side walls, a center frame coupled to the cooling plate to vertically divide a storage space defined by the side plates, and side beams coupled to the cooling plate to horizontally divide the spaces divided by the center frame.

[0030] Here, the cooling plate has slots formed therethrough along the joining positions of the center frame and / or the side beams.

[0031] In the pack case of the present invention having the above-described configuration, conductive heat transfer via the cooling plate between battery modules sandwiching the center frame or side beams is delayed by the slots. That is, by removing a portion of the heat conduction path between the battery modules via the cooling plate by the slots, excessive heat transfer caused by a battery module experiencing thermal runaway is suppressed and delayed, thereby improving the safety of the battery pack.

[0032] Hereinafter, specific embodiments of a pack case and a battery pack according to the present invention will be described in detail with reference to the accompanying drawings. For reference, the directions of front, back, up, down, left, and right used in the following description to designate relative positions are intended to facilitate understanding of the invention, and unless otherwise specified, are based on the directions shown in the drawings.

[0033] (First embodiment) FIG. 1 is a diagram illustrating the overall configuration of a pack case 100 according to the present invention, and FIG. 2 is an exploded perspective view of the pack case 100 according to the present invention.

[0034] The present invention relates to a pack case 100 that houses a plurality of battery modules 200. Referring to Figures 1 and 2, the pack case 100 of the present invention includes a cooling plate 110, a side plate 120, a center frame 130, and a side beam 140.

[0035] The cooling plate 110 forms the bottom of the pack case 100 and plays a role in supporting the weight of the battery modules 200 installed therein. The cooling plate 110 also comes into contact with the entire bottom surface of the battery modules 200 and plays an important role in absorbing heat from the battery modules 200 to cool them. To this end, the cooling plate 110 may be made of a material with excellent thermal conductivity, such as an aluminum alloy, and has cooling channels 112 therein for effective cooling. A heat transfer medium, such as cooling water, circulates through the cooling channels 112, and the heat transfer medium absorbs heat generated in the battery modules 200 and releases it to the outside, thereby maintaining the temperature of the battery modules 200 at an appropriate level.

[0036] The side plate 120 refers to a plate member that is coupled to the edge of the cooling plate 110 to form a side wall. The side plate 120 separates the inside and outside of the pack case 100, and the cooling plate 110 and the side plate 120 form a basic space for safely storing the battery module 200.

[0037] The center frame 130 is a member coupled to the cooling plate 110 to vertically divide the storage space formed by the side plates 120, and the side beams 140 are members coupled to the cooling plate 110 to horizontally divide the multiple spaces divided by the center frame 130. The lattice-structured center frame 130 and side beams 140 improve the structural rigidity of the pack case 100 and form multiple individual storage spaces in which individual battery modules 200 can be stored separately from one another. In the illustrated embodiment, one center frame 130 and ten side beams 140 provide a total of eight individual storage spaces, and therefore the illustrated pack case 100 can accommodate eight battery modules 200.

[0038] As described above, the cooling plate 110 absorbs heat through the bottom surface of the battery module 200 to cool it, and therefore, for effective heat transfer, the cooling plate 110 is preferably made of a material with excellent thermal conductivity. However, while a cooling plate 110 with excellent thermal conductivity may be effective in controlling the temperature of the battery module 200 when the battery module 200 is operating normally, if thermal runaway occurs in one battery module 200, the excess heat may be rapidly diffused to other nearby battery modules 200 via the cooling plate 110, which is a drawback.

[0039] In the present invention, in order to delay heat transfer when thermal runaway occurs, the cooling plate 110 is configured to have slots 114 formed through it along the joining positions of the center frame 130 or the side beams 140. The center frame 130 and the side beams 140 form boundaries between adjacent battery modules 200, and the slots 114 delay conductive heat transfer through the cooling plate 110 between the battery modules 200 across the center frame 130 or the side beams 140. In other words, the slots 114 formed through the cooling plate 110 partially eliminate the heat conduction path between the battery modules 200, thereby reducing and delaying excessive heat transfer caused by a battery module 200 experiencing thermal runaway, thereby improving the safety of the battery pack 10.

[0040] 3 is a diagram illustrating a cooling plate 110. In the illustrated embodiment, the cooling plate 110 has a plurality of slots 114 formed therein, the plurality of slots being spaced apart along the joining position of the center frame 130 or the side beams 140. The slots 114 may be formed along the joining position of at least one of the center frame 130 and the side beams 140, and in the illustrated embodiment, all of the slots 114 are formed at each joining position of the center frame 130 and the side beams 140. Each slot 114 is formed to a size that does not expose the center frame 130 or the side beams 140 to the outside. That is, the width of the slot 114 is formed to be smaller than the thickness of the center frame 130 or the side beams 140.

[0041] In the illustrated embodiment, the slots 114 are formed in the shape of narrow elongated holes. This shape of the slots 114 takes into consideration the reduction of heat conduction through the cooling plate 110 without significantly impairing the structural rigidity and thermal capacity of the cooling plate 110. Depending on the embodiment, the slots 114 may be provided in various shapes suitable for this purpose.

[0042] 1 to 3, a plurality of slots 114 are distributed in a row, and fastening points 118 of the center frame 130 or the side beams 140 are formed in the spaces between the spaced-apart slots 114. The fastening points 118 refer to points at which the center frame 130 and the side beams 140 are fixed to the cooling plate 110. Various known fastening structures may be used as the fastening structure applied to the fastening points 118. For example, fastening methods such as screw connection using bolts, force fitting using pins, welding, etc. may be used.

[0043] The fastening points 118 of the center frame 130 and the side beams 140 may be distributed at both ends and between the rows of the plurality of slots 114. By distributing the fastening points 118 widely and evenly while avoiding the slots 114, the center frame 130 and the side beams 140 can be stably fixed together.

[0044] In addition, since the cooling channels 112 are provided inside the cooling plate 110 and the slots 114 are formed penetrating the cooling plate 110, it is preferable that the cooling channels 112 and the slots 114 are arranged so that they do not overlap or intersect with each other. This is because it is possible to prevent leaked coolant from flowing into the battery module 200 through the slots 114 in the unlikely event of an accident, and it is also considered that minimizing the heat transfer path around the slots 114 is more advantageous in terms of heat transfer delay.

[0045] (Second embodiment) 4 is a diagram illustrating a battery pack 10 according to the present invention. The battery pack 10 provided by the present invention includes the pack case 100 described in the first embodiment and battery modules 200 accommodated in respective storage spaces divided vertically and horizontally by a center frame 130 and side beams 140 of the pack case 100. In the illustrated embodiment, a total of eight battery modules 200 constitute one battery pack 10.

[0046] 5 is a view illustrating another embodiment of the battery pack 10 of FIG. 4. In the embodiment of FIG. 5, a thermal resin layer 210 is interposed on the contact surface between the battery module 200 and the cooling plate 110. The thermal resin layer 210 serves to smoothly transfer heat from the battery module 200 to the cooling plate 110. For this reason, the material forming the thermal resin layer 210 needs to be a resin material with excellent thermal conductivity. In addition, the thermal resin layer 210 is preferably formed to an optimal thickness for heat conduction while filling in minute irregularities present on the contact surface between the battery module 200 and the cooling plate 110.

[0047] Furthermore, it is preferable that the thermal resin layer 210 is formed so as not to intrude into the slots 114. This is because the role of the slots 114 is to reduce and restrict the thermal conduction paths between the battery modules 200, and if the thermal resin layer 210 is formed up to the slots 114, it will adversely affect the original role of the slots 114.

[0048] 6 is a cross-sectional view illustrating another embodiment of the battery pack 10 of FIG. 4. Referring to FIG. 6, a thermal insulating material 116 is filled into the space formed by the slot 114. By filling the slot 114 with the thermal insulating material 116, which has a lower thermal conductivity than air, the heat transfer blocking effect of the slot 114 can be enhanced. In addition, by making the thermal insulating material 116 out of a watertight material, it can more effectively block coolant that may leak from the cooling channel 112. Furthermore, in consideration of the possibility of a fire breaking out inside the battery pack 10, it may be preferable to fill the slot 114 with the thermal insulating material 116 made of a flame-retardant material.

[0049] 6, the battery pack 10 may further include a base plate 150 coupled to the bottom surface of the cooling plate 110. The base plate 150 reinforces the structural rigidity of the bottom surface of the battery pack 10 and protects the cooling plate 110 having the cooling channels 112.

[0050] According to an embodiment, the base plate 150 may include base slots 152 corresponding to the slots 114 formed in the cooling plate 110. That is, the base slots 152 and the slots 114 of the cooling plate 110 are aligned to overlap one another, and heat from the cooling plate 110 may be dissipated to the outside through the base slots 152.

[0051] 7 is a diagram illustrating a heat transfer delay structure using slots 114 formed in a cooling plate 110. The slots 114, which penetrate the cooling plate 110, are arranged along the joining positions of the center frame 130 and the side beams 140. Because the center frame 130 and the side beams 140 form a boundary between adjacent battery modules 200, the slots 114 formed along the boundary between the battery modules 200 serve to eliminate part of the heat conduction path between the battery modules 200 via the cooling plate 110. Therefore, conductive heat transfer between the battery modules 200 on both sides of the center frame 130 and / or the side beams 140 is significantly delayed by the slots 114. As a result, excessive heat transfer to the surroundings caused by a battery module 200 experiencing thermal runaway is reduced and delayed, thereby improving the safety of the battery pack 10.

[0052] The present invention has been described in more detail above with reference to the drawings and embodiments, etc. However, the configurations described in the drawings or embodiments, etc. in this specification are merely one embodiment of the present invention and do not represent all of the technical ideas of the present invention, so it should be understood that there may be various equivalents and modifications that can replace them at the time of filing this application. [Explanation of symbols]

[0053] 10: Battery pack 100: Pack case 110: Cooling plate 112: Cooling channel 114: Slot 116:Insulation material 118: Connection point 120: Side plate 130: Center frame 140: Side beam 150: Base plate 152: Base Slot 200: Battery module 210: Thermal resin layer

Claims

1. a cooling plate having a cooling channel therein; a side plate coupled to an edge of the cooling plate to form a side wall; a center frame coupled to the cooling plate so as to vertically divide a storage space formed by the side plates; side beams coupled to the cooling plate so as to horizontally divide the plurality of spaces divided by the center frame; Including, The cooling plate has a slot formed therethrough along a joining position of the center frame or the side beam.

2. The slot is The pack case according to claim 1 , wherein a through hole is formed along a joining position of the center frame and the side beams.

3. A plurality of the slots are provided, The pack case according to claim 1 , wherein a plurality of the slots are spaced apart along a joining position of the center frame or the side beams.

4. The slot is The pack case according to claim 3 , wherein the center frame and the side beams are not exposed to the outside.

5. The pack case according to claim 3 , wherein fastening points for the center frame or the side beams are formed between the spaced apart slots.

6. The fastening point is The pack case according to claim 5 , wherein the plurality of slots are distributed at both ends and between the plurality of slots forming one row.

7. The cooling plate is The pack case of claim 1 , characterized by the cooling channels and the slots not overlapping or intersecting one another.

8. The pack case according to claim 1 , wherein a space formed by the slot is filled with a heat insulating material.

9. 9. The pack case according to claim 8, wherein the insulating material is a watertight material.

10. The pack case according to claim 1 , further comprising a base plate coupled to a bottom surface of the cooling plate.

11. The base plate is The pack case according to claim 10 , further comprising a base slot corresponding to the slot formed in the cooling plate.

12. The pack case according to any one of claims 1 to 11, battery modules housed in respective storage spaces divided vertically and horizontally by the center frame and side beams of the pack case; Including the battery pack.

13. The battery pack according to claim 12, wherein conductive heat transfer through the cooling plate between battery modules with the center frame or the side beams therebetween is delayed by the slots.

14. The battery pack according to claim 12 , wherein a thermal resin layer is interposed on a contact surface between the battery module and the cooling plate.

15. The battery pack of claim 14 , wherein the thermal resin layer does not intrude into the slot.

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