Battery pack

Abstract

The present invention relates to a battery pack accommodating a battery module, comprising: a pack case providing a space in which a battery module is mounted; an upper cover coupled to the pack case to cover an upper portion of a battery module mounted in the pack case; and a screen cover interposed between the pack case and the upper cover, wherein the screen cover includes a through hole opened to expose an upper portion of the battery module to the outside.

Description

[Technical Field]

[0001] The present invention relates to a battery pack, characterized in that a screen cover is applied to extinguish a flame when a flame occurs along with high-temperature gas in one of a plurality of battery modules housed therein, so that the flame is not directly exposed to the outside.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0136062, filed on October 21, 2022, and all contents disclosed in the documents of this Korean patent application are incorporated herein by reference. [Background technology]

[0003] Lithium secondary batteries have the risk of explosion, fire, etc. due to heat generation, and ensuring safety is an important issue. If such an abnormal phenomenon occurs and an appropriate response is not taken in the early stages, the internal temperature of the secondary battery will rise rapidly due to heat generation, and the rapid rise in temperature may cause a thermal runaway phenomenon, which may lead to the explosion of the secondary battery, and the explosion may spread to adjacent secondary batteries, causing serious damage to the battery pack.

[0004] To eliminate such dangers, some systems are equipped with a control means for monitoring and controlling the voltage, current, etc. of the battery pack, or with a means for extinguishing the fire externally in the event of a fire in the battery pack. However, these means alone have the problem of not being able to respond quickly and actively to a fire that occurs in the battery pack in the early stages.

[0005] FIG. 1 is a perspective view of a conventional battery pack 10 including a pack case and a battery module M housed in the internal space of the pack case.

[0006] In the battery pack 10 having the above structure, when thermal runaway occurs in any one of the battery modules M housed therein, the flame generated in the battery module M may be discharged to the outside through the upper part. Most battery packs 10 may further include an upper cover coupled to the pack case to cover the upper part of the battery module M, but there is a high risk that the upper cover may also be damaged by exposure to the flame. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Korean Patent Publication No. 10-2022-0004854 Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, the present invention has been made to solve the above problems, and an object of the present invention is to provide a battery pack that can prevent a flame generated along with the thermal runaway from being directly exposed to the outside even if a thermal runaway phenomenon occurs in a battery module housed therein.

[0009] Other objects and advantages of the present invention can be understood from the following description and become more apparent from the embodiments of the present invention. Also, it is easily understood that the objects and advantages of the present invention can be realized by the means and combinations thereof as claimed. [Means for solving the problem]

[0010] According to the present invention, a battery pack accommodating battery modules includes a pack case providing a space in which the battery modules are installed, an upper cover coupled to the pack case to cover an upper portion of the battery modules installed in the pack case, and a screen cover interposed between the pack case and the upper cover, The screen cover may include a through-hole that is opened to expose an upper portion of the battery module to the outside.

[0011] The screen cover may include a plurality of through holes, and the through holes may be formed at predetermined intervals along the horizontal and vertical axes of the screen cover.

[0012] The through-hole may be formed in at least one of a circular shape and a polygonal shape.

[0013] The pack case may include a base plate supporting a lower portion of a battery module, a main partition wall coupled across a center of the base plate, and a side wall coupled along an edge of the base plate, the pack case including a pair of module regions partitioned by the main partition wall, and the screen cover may be coupled to the pack case to cover at least one of the pair of module regions.

[0014] The pack case includes a base plate supporting a lower portion of the battery module, a main partition wall coupled across a center of the base plate, a side wall coupled along an edge of the base plate, and a sub-partition wall whose both ends are coupled to the main partition wall and the side wall, respectively, and which is coupled to the base plate at a predetermined interval along a longitudinal direction of the main partition wall, and the pack case includes a plurality of module areas defined by the main partition wall and the sub-partition wall, and the screen cover may be coupled to the pack case to cover at least one of the plurality of module areas.

[0015] The side of the screen cover includes a plurality of protrusions protruding laterally and grooves formed between the plurality of protrusions, and a pair of adjacently arranged screen covers can be joined together by interlocking the protrusions and grooves.

[0016] The screen cover may include a flame-resistant material.

[0017] The screen cover may further include a rupturable member coupled to an inner circumferential surface of the through hole to close the through hole.

[0018] The rupture member may comprise a thermoplastic material, and the through-hole may be opened as the rupture member melts due to high temperature heat generated in the module area.

[0019] The rupturable member is coupled to the through-hole so as to be broken when a pressure above a certain level is applied, and the through-hole can be opened by the rupturable member being broken by high-pressure gas generated in the module region.

[0020] A plurality of screen covers may be stacked and interposed between the upper cover and the pack case.

[0021] The plurality of screen covers may have the through holes arranged at the same positions.

[0022] Any one of the plurality of screen covers may be disposed at a position where the through-hole is blocked by another screen cover.

[0023] The through-hole may be formed in a slit shape. [Effects of the Invention]

[0024] According to the present invention, even if thermal runaway occurs in a battery module housed inside, the stability of the battery pack can be improved by suppressing the phenomenon in which the flame generated at the same time as the thermal runaway spreads to the outside. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a perspective view of a conventional battery pack. [Figure 2]1 is a perspective view of a battery pack according to a first embodiment of the present invention; [Figure 3] 1 is a plan view of a battery pack excluding a top cover. [Figure 4] 4 is a cross-sectional view of a portion between sub-partitions of the battery pack of FIG. 3. [Figure 5] 1 shows a first modified example of the screen cover. [Figure 6] 10 shows a second modified example of the screen cover. [Figure 7] 10 shows a third modified example of the screen cover. [Figure 8] 10 shows a fourth modified example of the screen cover. [Figure 9] FIG. 10 is a perspective view of a battery pack according to a second embodiment of the present invention. [Figure 10] FIG. 10 is a plan view of the battery pack of FIG. 9 with the top cover removed. [Figure 11] FIG. 10 is a perspective view of a battery pack according to a third embodiment of the present invention. [Figure 12] FIG. 12 is a plan view of the battery pack of FIG. 11 with the top cover removed. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Before that, the terms and words used in the specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as meanings and concepts that are consistent with the technical idea of ​​the present invention, based on the principle that the inventor can appropriately define the concepts of the terms to best describe his own invention.

[0027] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent the entire technical idea of ​​the present invention, and there may be various equivalents and modifications that can replace them at the time of this application.

[0028] Furthermore, in the description of the present invention, if it is determined that a detailed description of related publicly known structures or functions may obscure the gist of the present invention, the detailed description will be omitted.

[0029] The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art, and therefore the shapes and sizes of components in the drawings may be exaggerated, omitted, or shown in a schematic manner for clearer explanation. Therefore, the sizes and proportions of each component do not completely reflect the actual sizes and proportions.

[0030] The present invention relates to a battery pack, characterized in that when a flame occurs along with high-temperature gas in one of a plurality of battery modules housed therein, a screen cover is applied to extinguish the flame so that the flame is not directly exposed to the outside.

[0031] Figures 3 to 6 relate to a battery pack according to a first embodiment of the present invention, Figures 9 and 10 relate to a battery pack according to a second embodiment of the present invention, and Figures 11 and 12 relate to a battery pack according to a third embodiment of the present invention.

[0032] Hereinafter, a battery pack according to each embodiment of the present invention will be described with reference to the drawings.

[0033] (First embodiment) FIG. 2 is a perspective view of the battery pack 1000 according to the first embodiment of the present invention.

[0034] The battery pack 1000 of the present invention includes a pack case 100, an upper cover 300, and a screen cover 200, as shown in FIG.

[0035] The pack case 100 serves to provide a space in which the battery module M is installed, and surrounds and protects the bottom and sides of the battery module M installed therein.

[0036] The pack case 100 includes a base plate 110 that supports the lower portion of the battery module M, and a side wall 120 that is coupled along the edge of the base plate 110 and supports the side surface of the battery module M.

[0037] The pack case 100 may further include a main partition 130 coupled across the center of the base plate 110 .

[0038] The main partition 130 divides the inner space of the pack case 100 into two large spaces.

[0039] Various measuring wires and bus bars may be inserted into the main bulkhead 130 .

[0040] The pack case 100 includes a pair of module regions partitioned by the main partition wall 130, and one or more battery modules M can be installed in each module region.

[0041] The pack case 100 may further include a sub-partition 140 having both ends connected to the main partition 130 and the side wall 120, respectively.

[0042] The sub-barrier 140 serves to re-divide the module area formed on one side of the main barrier 130 and separate the battery modules M from each other.

[0043] The sub-partition walls 140 are coupled to the base plate 110 at both sides of the main partition wall 130 along the longitudinal direction of the main partition wall 130 with a predetermined interval therebetween.

[0044] The upper cover 300 covers the upper portion of the battery module M installed in the pack case 100 to protect it from external impact, and is combined with the pack case 100. More specifically, the upper cover 300 is combined with the side wall 120 included in the pack case 100 to completely surround and protect the upper portion of the battery module M inside.

[0045] The screen cover 200 is interposed between the pack case 100 and the upper cover 300, and covers the upper part of each battery module M from the lower part of the upper cover 300.

[0046] FIG. 3 is a plan view of the battery pack 1000 excluding the upper cover 300, and FIG. 4 is a cross-sectional view of a portion between the sub-partition walls 140 in the battery pack 1000 of FIG.

[0047] As shown in FIGS. 2 and 3, the screen cover 200 includes a through-hole 210 that is opened to expose the upper portion of the battery module M to the outside.

[0048] The screen cover 200 including the through-holes 210 is coupled to the pack case 100 to cover the upper portion of the plurality of battery modules M mounted in the pack case 100 .

[0049] The screen cover 200 of the present invention plays a role in preventing the flames of a fire from spreading to the outside when a fire breaks out in the plurality of battery modules M housed therein.

[0050] Referring to FIG. 4, the flame is blocked by the screen cover 200 and cannot spread to the outside, but only moves along the lower surface of the screen cover 200 (D1), and the gas moves through the through-holes 210 (D2) and is discharged to the outside.

[0051] 4, the through-holes 210 formed in the screen cover 200 may serve as a passage for discharging high-temperature gas generated along with a fire, but may also prevent the flames from escaping. Therefore, the screen cover 200 may prevent the flames from directly contacting the upper cover 300, thereby preventing the fire from spreading to the entire battery pack 1000.

[0052] The screen cover 200 may be exposed to flames that may occur when the battery module M goes into a thermal runaway state, and must be able to withstand high temperatures in the exposed state. Therefore, the screen cover 200 preferably includes a material that is resistant to high temperatures and flames. That is, the screen cover 200 preferably includes a flame-resistant material.

[0053] The screen cover 200 can be coupled to the side wall 120 of the pack case 100 , as with the top cover 300 , or can be coupled to the main partition wall 130 and the sub-partition wall 140 .

[0054] A side surface of the screen cover 200 may include a plurality of protrusions 220 protruding laterally along an edge and grooves 230 formed between the plurality of protrusions 220. In this case, an upper portion of the side wall 120 of the pack case 100 may be structured to engage with the protrusions 220 and the grooves 230 of the screen cover 200, and the screen cover 200 may be fixed to the pack case 100 as the protrusions 220 and the grooves 230 are engaged and coupled with the side wall 120.

[0055] The size and number of the through-holes 210 may be designed to vary depending on the size and number of the battery modules M accommodated in the battery pack 1000.

[0056] However, it is preferable that the through-holes 210 are limited in size to such an extent that a flame generated in the battery module M is not exposed to the outside through the through-holes 210.

[0057] The screen cover 200 may include a plurality of through holes 210, and the through holes 210 may be spaced apart from each other at predetermined intervals.

[0058] The through-holes 210 are formed along the horizontal and vertical axes of the screen cover 200 as shown in FIGS.

[0059] If a fire occurs in the battery module M housed in the battery pack 1000 of the present invention, the flames from the fire spread upward to where the upper cover 300 is located. However, the battery pack 1000 of the present invention can prevent the flames from spreading upward through the screen cover 200 interposed between the upper cover 300 and the battery module M. In addition, the screen cover 200 can selectively exhaust high-temperature gas through the through-holes 210.

[0060] The battery pack 1000 of the present invention may include a plurality of screen covers 200. That is, the stacked plurality of screen covers 200 may not only prevent a fire occurring at the lower portion but also delay the transfer of high-temperature heat to the upper cover 300.

[0061] Figure 5 shows a first modified example of the screen cover 200, in which multiple screen covers 200 are stacked, and Figure 6 shows a second modified example of the screen cover 200, in which multiple screen covers 200 are stacked.

[0062] FIG. 5 shows a stacked configuration of multiple screen covers 200 with through holes 210 arranged in the same position, which allows gas to be discharged through the through holes 210 while preventing flames from being discharged.

[0063] 6 shows a stack of multiple screen covers 200 in which the through holes 210 are arranged at different positions. That is, the through holes 210 included in one of the multiple screen covers 200 are arranged at positions where they are blocked by another screen cover 200.

[0064] The screen cover 200 stacked in the form shown in FIG. 6 may not allow gas to be discharged smoothly, but has the advantage of being able to effectively prevent flames from being discharged.

[0065] The through-hole 210 may be circular as shown in the figure, but is not limited thereto. The through-hole 210 may be circular as shown in the figure, or may be polygonal.

[0066] FIG. 7 shows a third modified example of the screen cover 200, in which a rectangular through-hole 210 is formed.

[0067] The through-holes 210 may be formed in a circular or polygonal dot shape, or in a slit shape.

[0068] 8 shows a fourth modified example of the screen cover 200, which has slit-shaped through holes 210. The through holes 210 shown in FIG. 8 are formed to extend along the horizontal or vertical axis of the screen cover 200. The slit-shaped through holes 210 have a wider opening, but the width of the through holes 210 can be adjusted to prevent fire.

[0069] The screen cover 200 may further include a rupturable member (not shown) coupled to an inner circumferential surface of the through-hole 210 to close the through-hole 210 .

[0070] The rupture member may be ruptured by high-temperature heat or high-pressure gas generated by thermal runaway of the battery module M.

[0071] Specifically, the rupture member is normally coupled to the through-hole 210 to seal the battery module M housed therein, and can melt due to high temperature heat generated due to thermal runaway of the battery module M. That is, the through-hole 210 can be opened as the rupture member melts due to high temperature heat generated in the module area. In this case, the rupture member can include a thermoplastic material that can easily melt due to high temperature heat.

[0072] Alternatively, the rupture member may be broken by high-pressure gas generated due to thermal runaway of the battery module M. That is, the through-hole 210 may be opened by the rupture member being broken by high-pressure gas generated in the module area.

[0073] (Second embodiment) FIG. 9 is a perspective view of a battery pack 1000 according to a second embodiment of the present invention, and FIG. 10 is a plan view of the battery pack 1000 of FIG. 9 with the upper cover 300 removed.

[0074] The battery pack 1000 of the present invention includes a pack case 100, an upper cover 300, and a screen cover 200, as shown in FIG.

[0075] The screen cover 200 is coupled to the pack case 100 to cover at least one of a pair of module regions partitioned by the main partition wall 130. That is, the battery pack 1000 according to the second embodiment of the present invention is characterized in that a pair of the screen covers 200 can be separated and coupled to both sides of the main partition wall 130.

[0076] As described above, the screen covers 200 separated by the main partition wall 130 are not connected to each other, and therefore cannot transfer heat through conduction between them. Therefore, even if thermal runaway occurs in a battery module M accommodated on one side of the main partition wall 130 and the screen cover 200 covering the upper part of the battery module M is heated by high-temperature heat, the heat is not transferred to the other screen cover 200 arranged on the other side of the main partition wall 130.

[0077] (Third embodiment) FIG. 11 is a perspective view of a battery pack 1000 according to a third embodiment of the present invention, and FIG. 12 is a plan view of the battery pack 1000 of FIG. 11 with the upper cover 300 removed.

[0078] The battery pack 1000 of the present invention includes a pack case 100, an upper cover 300, and a screen cover 200, as shown in FIG.

[0079] The screen cover 200 is combined with the pack case 100 to cover at least one of a plurality of module regions defined by the main partition wall 130 and the sub-partition wall 140. That is, in the battery pack 1000 according to the third embodiment of the present invention, the screen cover 200 is combined with the pack case 100 to cover the module region between a pair of sub-partition walls 140 spaced a predetermined distance apart on both sides of the main partition wall 130.

[0080] One screen cover 200 may cover each module area, and at this time, a pair of adjacently arranged screen covers 200 may be coupled together by engaging the protrusions 220 and the grooves 230 with each other.

[0081] When one screen cover 200 is coupled to one module area as described above, the screen cover 200 can be selectively placed only in the required area, thereby reducing the number of screen covers 200 used, thereby further improving safety while at the same time improving the energy efficiency of the battery pack 1000.

[0082] The present invention has been described in more detail above with reference to the drawings and embodiments, etc. However, the configurations shown in the drawings or embodiments in this specification are merely one embodiment of the present invention and do not represent all of the technical ideas of the present invention, and therefore, there may be various equivalents and modifications that can replace them at the time of filing this application. [Explanation of symbols]

[0083] 10: (Prior Art) Battery Pack 1000: Battery pack 100: Pack case 110: Base plate 120: Side wall 130: Main bulkhead 140: Sub-partition 200:Screen cover 210:Through hole 220:Protrusion 230: Groove 300: Upper cover M: Battery module D1: Flame movement D2: Gas transfer

Claims

1. In a battery pack that accommodates a battery module, a pack case providing a space in which the battery module is installed; an upper cover coupled to the pack case to cover an upper portion of the battery module installed in the pack case; a screen cover interposed between the pack case and the upper cover and positioned below the upper cover to cover an upper portion of the battery module, the screen cover includes a through-hole that is opened to expose an upper portion of the battery module to the outside, The pack case is a base plate supporting a lower portion of the battery module; a main bulkhead coupled across a center of the base plate; a sidewall coupled along an edge of the base plate; a sub-partition wall, both ends of which are coupled to the main partition wall and the side wall, and which is coupled to the base plate at a predetermined interval along a longitudinal direction of the main partition wall, the pack case includes a plurality of module regions defined by the main partition wall and the sub partition wall, the screen cover is coupled to the sub-partition wall to cover at least one of the plurality of module regions; The side surface of the screen cover includes a plurality of protrusions protruding laterally and grooves formed between the plurality of protrusions, A pair of adjacently arranged screen covers are joined together by interlocking the protrusions and the grooves. Battery pack.

2. the screen cover includes a plurality of the through holes, The plurality of through holes are formed at predetermined intervals along the horizontal and vertical axes of the screen cover. The battery pack according to claim 1 .

3. The through-hole is formed in at least one shape of a circle and a polygon.

3. The battery pack according to claim 1 or 2.

4. The pack case includes a pair of module regions partitioned by the main partition wall, the screen cover is coupled to the sub-partition wall to cover at least one of the pair of module regions; 3. The battery pack according to claim 1 or 2.

5. The screen cover comprises a flame-resistant material.

3. The battery pack according to claim 1 or 2.

6. The screen cover further includes a rupturable member coupled to an inner circumferential surface of the through hole to close the through hole.

3. The battery pack according to claim 1 or 2.

7. the rupture member comprises a thermoplastic material; The through-hole is opened as the rupturable member melts due to high temperature heat generated in the module area. The battery pack according to claim 6.

8. the rupturable member is coupled to the through-hole so as to be broken when a pressure equal to or greater than a certain level is applied thereto; the through-hole is opened by the rupture member being destroyed by high-pressure gas generated in the module area; The battery pack according to claim 7.

9. The screen cover is interposed in a stacked manner.

3. The battery pack according to claim 1 or 2.

10. The plurality of screen covers have through holes arranged at the same positions. The battery pack according to claim 9.

11. Any one of the plurality of screen covers is disposed at a position where the through-hole is blocked by another screen cover. The battery pack according to claim 9.

12. The through-hole is formed in a slit shape.

3. The battery pack according to claim 1 or 2.

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