Battery pack with improved temperature deviation

Abstract

A battery pack with improved temperature deviation according to one embodiment of the present invention includes a plurality of cell module assemblies and a case that houses the cell module assemblies, the case including an air intake port through which cooling air flows in from the case, an exhaust port through which cooling air is discharged from the case, and a first side portion disposed on one side of the case, the first side portion including a plurality of first beads that protrude from the first side portion toward the inside of the case.

Description

[Technical Field]

[0001] The present invention relates to a battery pack, and more particularly to a battery pack that can improve temperature deviation between cell module assemblies within the battery pack. [Background technology]

[0002] Secondary batteries are batteries that can be charged and discharged repeatedly, unlike primary batteries which cannot be recharged. They are used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) that are powered by electrical sources.

[0003] Currently widely used secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of such a unit secondary battery cell, i.e., a single battery cell, is approximately 2.5V to 4.6V. Therefore, when a higher output voltage is required, a battery pack is constructed by connecting multiple battery cells in series. Alternatively, depending on the charge / discharge capacity required for the battery pack, a battery pack may be constructed by connecting multiple battery cells in parallel. Therefore, the number of battery cells included in the battery pack can be variously set depending on the required output voltage or charge / discharge capacity.

[0004] A common method for connecting multiple battery cells in series / parallel to form a battery pack is to first assemble a battery module consisting of at least one battery cell, preferably multiple battery cells, and then add other components to at least one module to form a pack. Here, a battery module refers to an assembly of multiple single cells connected in series / parallel, and a battery pack refers to a collection of multiple battery modules connected in series / parallel to increase capacity and output.

[0005] Typically, a battery pack has a plurality of battery modules or battery module assemblies arranged on the same plane to maintain structural stability.

[0006] In such a battery pack, heat is generated during charging and discharging, and it is necessary to remove the generated heat by an appropriate cooling method.

[0007] One example is a method of cooling the battery pack by injecting cooling air into the battery pack.

[0008] Although there is a problem of temperature deviation between cell module assemblies (CMA) in battery packs, controlling the temperature and temperature deviation of the battery pack is closely related to battery life and performance, and the smaller the temperature deviation, the more likely it is that the product quality and battery life will be improved. Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to provide a battery pack in which the temperature deviation between cell module assemblies (CMA) of the battery is improved. [Means for solving the problem]

[0010] A battery pack with improved temperature deviation according to one embodiment of the present invention includes a plurality of cell module assemblies and a case that houses the cell module assemblies, the case including an air intake port through which cooling air flows in from the case, an exhaust port through which cooling air is discharged from the case, and a first side portion disposed on one side of the case, the first side portion including a plurality of first beads that protrude from the first side portion toward the inside of the case.

[0011] The case further includes a second side surface disposed opposite the first side surface.

[0012] The cooling system further includes an inflow passage provided inside the first side surface of the case, through which the cooling air flowing in from the air intake port moves, and an outflow passage provided inside the second side surface of the case, through which the cooling air moves so that the cooling air can be discharged from the exhaust port.

[0013] The case further includes a third side surface portion disposed on the other side surface of the case, and a fourth side surface portion disposed opposite the third side surface portion.

[0014] Moreover, the air inlet is disposed on the third side surface portion, and the air outlet is disposed on the fourth side surface portion.

[0015] Furthermore, the plurality of cell module assemblies are arranged along the direction from the third side surface portion to the fourth side surface portion.

[0016] The first bead is formed so that the entire thickness of the first side surface portion protrudes toward the inside of the case.

[0017] Furthermore, the cell module assemblies are each disposed in front of the first beads.

[0018] Furthermore, the first bead is disposed on the first side surface portion so as to face the space between the cell module assembly.

[0019] The first beads are arranged so as to correspond to the cell module assemblies in order from the cell module assembly adjacent to the third side surface portion.

[0020] The first bead is disposed at a position within half the length of the first side surface portion from one end of the first side surface portion connected to the third side surface portion.

[0021] Furthermore, the number of the first beads is equal to or less than half the number of the cell module assemblies.

[0022] Moreover, the first bead has a trapezoidal cross section.

[0023] Moreover, the first bead has a triangular cross section.

[0024] Furthermore, the protruding height of the first bead from the first side surface portion gradually increases along the direction of movement of the cooling air flowing in from the air inlet.

[0025] Furthermore, the protruding height from the first side surface of the first bead from the air inlet is 15% to 25% of the distance between the first side surface and one end of the cell module assembly, the protruding height of the second first bead from the air inlet is 35% to 45% of the distance between the first side surface and one end of the cell module assembly, and the protruding height of the third first bead from the air inlet is 55% to 65% of the distance between the first side surface and one end of the cell module assembly.

[0026] Furthermore, in the first bead, the vertical height of the first side surface portion gradually increases along the direction of movement of the cooling air flowing in from the air inlet.

[0027] Additionally, the second side surface portion includes a plurality of second beads that protrude from the second side surface portion toward the inside of the case.

[0028] The case further includes a third side portion arranged on the other side of the case, and a fourth side portion arranged opposite the third side portion, and the second beads are arranged to correspond to the cell module assemblies in order from the cell module assemblies adjacent to the fourth side portion.

[0029] Furthermore, the protruding height of the second bead from the second side surface portion gradually decreases in the direction opposite to the direction of movement of the cooling air from the exhaust port.

[0030] The second bead is disposed at a position within half the length of the second side surface portion from one end of the second side surface portion connected to the fourth side surface portion.

[0031] Furthermore, the number of the second beads is equal to or less than half the number of the cell module assemblies. [Effects of the Invention]

[0032] According to the battery pack of the present invention, the temperature difference between the cell module assemblies in the battery pack is improved, thereby improving the battery performance and battery life.

[0033] Furthermore, the battery pack according to the present invention has improved temperature deviation and strengthened rigidity of the case, which allows the battery pack to be thinner and thus reduces costs. [Brief explanation of the drawings]

[0034] [Figure 1] 1 is a perspective view showing a battery pack according to a first embodiment of the present invention. [Figure 2] 1 is an exploded perspective view showing a battery pack according to a first embodiment of the present invention. [Figure 3] 1 is a rear perspective view showing a battery pack according to a first embodiment of the present invention. [Figure 4] 1 is a rear view showing a battery pack according to a first embodiment of the present invention. [Figure 5] 1 is a plan view showing the inside of a battery pack according to a first embodiment of the present invention. [Figure 6] FIG. 6 is a detailed view showing a part of FIG. 5. [Figure 7] FIG. 10 is a rear view showing a battery pack according to a second embodiment of the present invention. [Figure 8] FIG. 10 is a plan view showing the inside of a battery pack according to a third embodiment of the present invention. [Figure 9] FIG. 10 is a plan view showing the inside of a battery pack according to a fourth embodiment of the present invention. [Figure 10] FIG. 10 is a detailed view showing a part of FIG. 9. [Figure 11] FIG. 10 is a rear view showing a part of FIG. 9. [Figure 12] FIG. 10 is a diagram showing the results of a temperature distribution simulation of a battery pack according to a fourth embodiment of the present invention. [Figure 13] FIG. 10 is a detailed view showing a part of a battery pack according to a fourth embodiment of the present invention. [Figure 14] 1A and 1B are diagrams showing various examples of the present invention and comparative examples; [Figure 15] FIG. 15 is a diagram showing the temperature distribution in the test example shown in FIG. 14. [Figure 16] 15 is a graph showing the flow rate of each cell module assembly in the test example shown in FIG. 14. MODE FOR CARRYING OUT THE INVENTION

[0035] The advantages and features of the present invention, as well as methods for achieving the same, will become apparent from the following detailed description of the embodiments with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments and can be embodied in various modifications. These embodiments are provided for complete disclosure of the present invention and to fully convey the scope of the invention to those skilled in the art. The scope of the present invention should be defined by the scope of the claims. Therefore, in some embodiments, detailed descriptions of well-known processes and steps, well-known device structures, and well-known techniques will be omitted to avoid obscuring the gist of the present invention. Throughout this specification, the same reference numerals refer to the same components.

[0036] In the drawings, thicknesses are exaggerated to clearly show multiple layers and regions. Similar parts are designated by the same reference numerals throughout the specification. When a layer, film, region, plate, or other part is described as being "on" 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 between them. Conversely, when a part is described as being "directly above" another part, it means that there are no other parts between them. Furthermore, when a layer, film, region, plate, or other part is described as being "under" another part, it includes not only the case where it is "directly below" the other part, but also the case where there are other parts between them. Conversely, when a part is described as being "directly below" another part, it means that there are no other parts between them.

[0037] Hereinafter, a battery pack with improved temperature deviation according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0038] FIG. 1 is a perspective view showing a battery pack according to a first embodiment of the present invention, FIG. 2 is an exploded perspective view showing a battery pack according to the first embodiment of the present invention, FIG. 3 is a rear perspective view showing a battery pack according to the first embodiment of the present invention, FIG. 4 is a plan view showing the interior of the battery pack according to the first embodiment of the present invention, and FIG. 6 is a detailed view showing a part of FIG. 5.

[0039] The battery pack 1000 with improved temperature deviation according to the present invention includes a plurality of cell module assemblies (CMA) 100 and a case 200 that houses the plurality of cell module assemblies 100.

[0040] The cell module assemblies 100 housed in the battery pack 1000 include a plurality of battery cells (not shown), and in each cell module assembly 100, the plurality of battery cells are arranged in close contact with each other.

[0041] Each battery cell may be, for example, a pouch-type cell.

[0042] For example, the cell module assembly 100 includes a plurality of battery cells stacked or tightly attached to each other, and each battery cell has an electrode lead at its front end and / or rear end, with an anode lead provided at the front end and a cathode lead provided at the rear end. In the cell module assembly 100, the plurality of battery cells are arranged so as to be electrically connected to each other.

[0043] In the cell module assembly 100, the battery cells are not limited to pouch-type cells, and may be configured with cells having other shapes, such as prismatic cells.

[0044] The cell module assembly 100 may be arranged in an open manner within the case 200 of the battery pack 1000 without providing a separate housing. As another example, the cell module assembly 100 may have multiple cells housed in a housing, or the cell module assemblies 100 may be housed in individual housings and arranged independently within the case 200 of the battery pack 1000.

[0045] The case 200 is for housing a plurality of cell module assemblies 100 and comprises a lower surface portion 260, an upper surface portion 250, a first side surface portion 220, a second side surface portion 210, a third side surface portion 230, and a fourth side surface portion 240.

[0046] The lower surface portion 260 of the case 200 is in the shape of a plate extending horizontally and forms the bottom of the case 200, and a plurality of cell module assemblies 100 are arranged on the upper portion of the lower surface portion 260.

[0047] As shown, the multiple cell module assemblies 100 are arranged at regular intervals in the direction from the third side portion 230 (located on the left side of the case 200 in Figure 5) to the fourth side portion 240 (located on the right side of the case 200 in Figure 5).

[0048] In the case 200, the third side portion 230 and the fourth side portion 240 form the left and right sides of the case 200, respectively, in this embodiment, and the third side portion 230 and the fourth side portion 240 are respectively disposed on the left and right edges of the bottom portion 260.

[0049] 3 to 6, the third side surface 230 of the case 200 has a rectangular plate shape, and is provided with an air intake port 201. Cooling air for use as a refrigerant flows in through the air intake port 201 to cool the cell module assembly 100 arranged in the battery pack 1000, and after cooling the cell module assembly 100, the cooling air that flows in through the air intake port 201 is discharged through an exhaust port 202 provided in the fourth side surface 240 on the opposite side.

[0050] In this embodiment, the air intake port 201 is provided in the rear portion of the third side portion 230, which is connected to the first side portion 220, and the cooling air flowing in from the air intake port 201 moves along the inlet movement passage 205 between the rear plate 120 and the first side portion 220, which will be described later.

[0051] The fourth side surface portion 240 of the case 200 has a rectangular plate shape and is disposed parallel to the third side surface portion 230. The length of the fourth side surface portion 240 is the same as that of the third side surface portion 230, and an exhaust port 202 may be provided in the fourth side surface portion 240. Cooling air for the refrigerant used to cool the cell module assembly 100 is discharged from the exhaust port 202. In this embodiment, the exhaust port 202 is provided in a front portion of the fourth side surface portion 240 that is connected to the second side surface portion 210, and as shown in the figure, the exhaust port 202 is provided diagonally from the air supply port 201 provided in the third side surface portion 230.

[0052] Therefore, the cooling air that has cooled the cell module assembly 100 moves along an outflow transfer path 206 between the front plate 110 and the second side portion 210 (described later) and is discharged from the exhaust port 202.

[0053] In this embodiment, a fan (not shown) is provided at the exhaust port 202. The cooling air that has flowed in from the air intake port 201 is discharged through the exhaust port 202 by the fan provided at the exhaust port 202.

[0054] In another embodiment, cooling air may be introduced into the case 200 by a fan, in which case the exhaust port 202 becomes an intake port and the intake port 201 becomes an exhaust port.

[0055] Furthermore, in other embodiments, the fan may be provided in the air intake vent 201 instead of the exhaust vent 202. In such a case, the fan also allows cooling air from the outside to flow into the battery pack, and the fan also allows cooling air from inside the battery pack to be exhausted to the outside.

[0056] In this embodiment, the first side surface portion 220 and the second side surface portion 210 of the case 200 respectively form the rear and front surfaces of the case 200 (see FIG. 5). The first side surface portion 220 and the second side surface portion 210 are respectively disposed on the rear and front edges of the bottom surface portion 260. The second side surface portion 210 is disposed parallel to the first side surface portion 220 so as to face each other, and the length of the second side surface portion 210 may be the same as the length of the first side surface portion 220.

[0057] Also, inside the case 200, as shown in the figure, a front plate 110 is arranged parallel to and spaced inward from the second side portion 210, and a rear plate 120 is arranged parallel to and spaced inward from the first side portion 220.

[0058] Each cell module assembly 100 is arranged between a front plate 110 and a rear plate 120, but one end of each cell module assembly 100 may be arranged on the rear plate 120 and the other end of each cell module assembly 100 may be arranged on the front plate 110.

[0059] In addition, the front plate 110 may have multiple openings 111 so that the other end of each cell module assembly 100 is connected to the space between the front plate 110 and the second side portion 210, and the rear plate 120 may have multiple openings so that one end of each cell module assembly 100 is connected to the space between the rear plate 120 and the first side portion.

[0060] Furthermore, an inflow movement passage 205 is provided between the first side portion 220 and the rear plate 120 (one end of the cell module assembly 100) through which cooling air flowing in from the air intake port 201 moves, and an outflow movement passage 206 is provided between the second side portion 210 and the front plate 110 (the other end of the cell module assembly).

[0061] Therefore, the cooling air moves along the inlet movement passage 205 between the first side portion 220 and the rear plate 120 (one end of the cell module assembly 100), passes through each cell module assembly 100 through the openings in the rear plate 120, then moves to the outlet movement passage 206 between the second side portion 210 and the front plate 110 (the other end of the cell module assembly) through the openings 111 in the front plate 110, and is then discharged through the exhaust port 202.

[0062] In each cell module assembly 100, the electrode leads (anode / cathode leads) of the battery cells are electrically connected to the front plate 110 and the rear plate 120, respectively.

[0063] In this manner, the first side surface portion 220 , the second side surface portion 210 , the third side surface portion 230 , and the fourth side surface portion 240 of the case 200 form the side surfaces of the case 200 .

[0064] An upper surface portion 250 is located at the top of the case 200. The upper surface portion 250 has a plate shape extending horizontally and is disposed above the cell module assembly 100. A first side surface portion 220, a second side surface portion 210, a third side surface portion 230, and a fourth side surface portion 240 are connected to the edges of the upper surface portion 250. In this embodiment, the upper surface portion 250 is formed integrally with the first side surface portion 220 and the second side surface portion 210.

[0065] In this embodiment, the case 200 is shown as a rectangular box in the drawing, but is not limited to this and may have various shapes including a polygonal shape.

[0066] In the present invention, a plurality of first beads 300 and second beads 350 are arranged on the inside of the first side surface portion 220 and / or the second side surface portion 210 of the case 200.

[0067] 5 is a plan view showing the interior of a battery pack 1000 according to a first embodiment of the present invention. In this first embodiment of the present invention, six cell module assemblies 100 are arranged, and three first beads 300 are provided on the inside of the first side surface portion 220 of the case 200. The first beads 300 are arranged within half the length (L) of the first side surface portion 220 from one end of the first side surface portion 220 connected to the third side surface portion 230 to the other end of the first side surface portion 220 connected to the fourth side surface portion 240, and the number of first beads 300 is half or less of the number of cell module assemblies.

[0068] The first beads 300 are intended to improve the temperature deviation between the cell module assemblies 100 within the pack, and in the first embodiment, they are formed to protrude from the first side portion 220 toward the cell module assemblies 100, and three first beads 300 are arranged in a row in the direction of movement of the cooling air from one end of the first side portion 220 adjacent to the air intake port 201.

[0069] Therefore, in the first embodiment, the first beads 300 are arranged on the first side surface portion 220 so as to correspond to each of the three cell module assemblies 100 adjacent to the air supply port 201 (or the third side surface portion 230). As shown in the figure, each first bead 300 may be arranged at a position corresponding to the center of one end of each cell module assembly 100.

[0070] Since the first bead 300 is processed by pressing the first side portion 220 with a press during the manufacturing process, it may be formed so that the entire thickness (all of the thickness) of the first side portion 220 protrudes inside the case 200, or may be formed so as to have a trapezoidal cross section as shown in Figures 5 and 6.

[0071] Specifically, the first bead 300 includes two inclined surface portions 300a bent from the first side surface portion 220, and a protruding end portion 300b connecting the two inclined surface portions 300a.

[0072] Furthermore, in cross section, the long side of the two parallel sides of the trapezoid forming the first bead 300 may be located on the same plane as the first side surface portion 220, and the short side may correspond to the protruding end portion 300b of the first bead 300. The inclination angle (α) of the inclined surface portion 300a of the first bead 300 relative to the first side surface portion 220 is an obtuse angle, specifically within a range of 130 degrees to 140 degrees, or approximately 135 degrees. That is, the inclination angle of the inclined surface portion 300a relative to the long side of the trapezoid may be within a range of 40 degrees to 50 degrees, or approximately 45 degrees.

[0073] The protruding end portion 300b is a flat surface that connects the ends of the two inclined surface portions 300a to each other, and is formed parallel to the first side surface portion 220.

[0074] In the present invention, since the cross section of the first bead 300 is trapezoidal, the cooling air from the air intake 201 moves linearly along the inclined surface portion 300a, thereby guiding the cooling air to each cell module assembly 100.

[0075] The protruding height (D) of the first bead 300 from the first side surface portion 220 may be within approximately 25% to 35%, or within approximately 5% to 65% of the distance between the first side surface portion 220 and the rear plate 120. For example, the protruding height of the first bead 300 is approximately 7.5 mm, and may be approximately 15 mm. In the first embodiment, three identical first beads 300 are provided, and the protruding height (D) of each of the first beads 300 is the same.

[0076] Furthermore, in the first side surface portion 220, the vertical height (H) from the upper end to the lower end of the first bead 300 may be 50% to 100%, 60% to 90%, or 70% to 80% of the height of the first side surface portion 220.

[0077] As described above, in such a battery pack 1000, cooling air moves along the inlet movement passage 205 between the rear plate 120 and the first side portion 220, passes through each cell module assembly 100 through the openings in the rear plate 120, moves to the outlet movement passage 206 between the front plate 110 and the second side portion through the openings in the front plate 110, and is then discharged from the exhaust port 202. However, since less cooling air flows into the cell assembly arranged adjacent to the air intake port, the cooling efficiency may be reduced.

[0078] In the present invention, the first bead 300 is provided on the first side surface 220 to strengthen the pack rigidity, and this strengthening of the rigidity allows the case thickness to be reduced, resulting in cost reduction. Also, in the present invention, cooling air is smoothly guided to the cell module assemblies 100 adjacent to the air inlet 201, reducing the temperature difference between the cell module assemblies 100 and improving the quality and battery life of the battery pack.

[0079] Next, a battery pack 1000 in which temperature deviation is improved according to a second embodiment of the present invention will be described.

[0080] FIG. 7 is a rear view showing a battery pack 1000 according to a second embodiment of the present invention.

[0081] The battery pack 1000 according to the second embodiment of the present invention differs from the first embodiment in that, while in the first embodiment, the vertical height (H) from the top to the bottom of the first beads 300 provided on the first side portion 220 is the same for all three first beads 300, in the second embodiment, the vertical heights (H) of the three first beads 300 are different from one another.

[0082] In this embodiment, the vertical height (H) of the first bead 300 provided on the first side portion 220 is formed so as to gradually increase from one end of the first side portion 220 adjacent to the air intake port 201 along the direction of movement of the cooling air.

[0083] Specifically, the vertical height (H) of the second first bead 300 is increased by 10% to 20% compared to the first first bead 300 (located on the far right in Figure 7) that is closest to the air intake port 201, and the third first bead 300 that is farthest from the air intake port 201 is increased by 20% to 30% compared to the first first bead 300.

[0084] In the second embodiment, the vertical height (H) of the first bead 300 is set to gradually increase along the direction of movement of the cooling air from the air intake port 201, thereby preventing excessive inflow of cooling air toward the first cell module assembly 100 corresponding to the first first bead 300, and efficiently dispersing the cooling air to reduce temperature deviation.

[0085] Next, a battery pack 1000 in which temperature deviation is improved according to a third embodiment of the present invention will be described.

[0086] FIG. 8 is a plan view showing the inside of a battery pack 1000 according to a third embodiment of the present invention.

[0087] The battery pack 1000 according to the third embodiment of the present invention differs from the first embodiment in that, while in the first embodiment the first bead 300 is provided only on the first side surface portion 220, in the third embodiment the first bead 300 is also provided on the second side surface portion 210.

[0088] In the third embodiment, six cell module assemblies 100 are arranged inside a case 200, three first beads 300 are arranged inside a first side surface portion 220 of the case 200, and three second beads 350 similar to the first beads 300 are arranged inside a second side surface portion 210. The size of the second beads 350 may be the same as that of the first beads 300.

[0089] In this embodiment, the three first beads 300 provided on the first side portion 220 are formed to protrude from the first side portion 220 in the direction of the cell module assembly 100, as in the first embodiment, and the three first beads 300 are provided along the direction of movement of the cooling air from one end of the first side portion 220 adjacent to the air intake port 201, and are arranged to correspond to the three cell module assemblies adjacent to the air intake port 201, respectively.

[0090] In this embodiment, the three second beads 350 provided on the second side portion 210 are intended to improve the temperature deviation between the cell module assemblies 100, similar to the first beads 300. The second beads 350 have the same configuration as the first beads 300 and are formed to protrude from the second side portion 210 toward the cell module assemblies 100. The three second beads 350 are provided along the opposite direction to the movement direction of the cooling air from one end of the second side portion adjacent to the exhaust port 202, and are arranged to correspond to the three cell module assemblies 100 adjacent to the exhaust port 202, respectively.

[0091] Similar to the first bead 300, the second bead 350 is formed so that the entire thickness of the second side surface portion 210 protrudes toward the inside of the case 200, and has a trapezoidal cross section. Of the two parallel sides of the trapezoid that form the second bead 350, the long side is located on the same plane as the second side surface portion 210, and the short side is located at the protruding end of the second bead 350.

[0092] In the present invention, since the cross section of the second bead 350 is trapezoidal, the cooling air that has cooled the cell module assembly 100 moves along the outflow movement passage 206, and the cooling air is guided to each cell module assembly 100 along the inclined sides of the trapezoid.

[0093] The protruding height of the second bead 350 from the second side surface portion 210 may be the same as that of the first bead 300. As an example, the protruding height of the second bead 350 may be within about 25% to 35%, or within about 55% to 65% of the distance between the first side surface portion 220 and the other end (front plate 110) of the cell module assembly 100. As an example, the protruding height of the second bead 350 is about 7.5 mm, or may be about 15 mm. In this embodiment, the protruding heights of all three second beads 350 are the same.

[0094] In addition, the position of the second bead 350 is within 1 / 2 of the length of the second side portion 210 from one end of the second side portion 210 connected to the fourth side portion 240 to the other end of the second side portion 210 connected to the third side portion 230, and the number of second beads 350 is 1 / 2 or less of the cell module assembly.

[0095] Therefore, in this embodiment, first beads 300 are arranged on the first side surface portion 220 adjacent to the air intake port 201 for the number of cell module assemblies 100 corresponding to half of the total, and second beads 350 are arranged on the second side surface portion 210 adjacent to the air exhaust port 202 for the number of cell module assemblies 100 corresponding to the remaining half.

[0096] In this embodiment, the cooling air moves along the inlet movement passage 205 between the rear plate 120 and the first side portion 220, and is smoothly guided to the cell module assembly 100 adjacent to the air intake port 201 by the first bead 300 of the first side portion 220.Furthermore, before the cooling air moves to the outlet movement passage 206 between the front plate 110 and the second side portion 210 and is discharged to the exhaust port 202, the cooling air is guided to the adjacent cell module assembly 100 by the second bead 350 of the second side portion 210, further reducing the temperature deviation between the cell module assemblies 100.

[0097] The other configurations and effects are the same as those of the first embodiment, so detailed description thereof will be omitted here.

[0098] Next, a battery pack 1000 in which temperature deviation is improved according to a fourth embodiment of the present invention will be described.

[0099] FIG. 9 is a plan view showing the inside of a battery pack according to a fourth embodiment of the present invention, FIG. 10 is a detailed view showing a part of FIG. 9, FIG. 11 is a rear view showing a part of FIG. 9, and FIG. 12 is a diagram showing the results of a temperature distribution simulation of the battery pack according to the fourth embodiment of the present invention.

[0100] The battery pack 1000 according to the fourth embodiment of the present invention differs from the first embodiment in that, while in the first embodiment three identical first beads 300 are provided on the first side surface portion 220, in the fourth embodiment the protruding height (D) of the first beads 300 from the first side surface portion 220 (the distance between the first side surface portion 220 and the protruding end portion 300b of the first bead 300) is different.

[0101] In the fourth embodiment, first beads 300 are provided on the first side surface 220 so as to correspond to each of the three cell module assemblies 100 adjacent to the air intake port 201, and the protruding height (D) of the first beads 300 from the first side surface 220 is formed so as to gradually increase from one end of the first side surface adjacent to the air intake port 201 along the direction of movement of the cooling air.

[0102] Specifically, the protruding height (D) of the first first bead 300 closest to the air intake port 201 from the first side surface portion 220 is within approximately 15% to 25% of the distance between the first side surface portion 220 and one end of the cell module assembly 100 (or the rear plate 120), the protruding height (D) of the second first bead 300 from the first side surface portion 220 is within approximately 35% to 45% of the distance between the first side surface portion 220 and one end of the cell module assembly 100 (or the rear plate 120), and the protruding height (D) of the third first bead 300 from the first side surface portion 220 is within approximately 55% to 65% of the distance between the first side surface portion 220 and one end of the cell module assembly 100 (or the rear plate 120). As an example, of the three first beads 300 protruding from the first side surface portion 220, the height of the first first bead 300 may be approximately 5 mm, the height of the second first bead 300 may be approximately 10 mm, and the height of the third first bead 300 may be approximately 15 mm. Also, as shown in Fig. 11, the left and right widths of the first beads 300 on the first side surface portion 220 are formed to gradually increase along the direction of movement of the cooling air.

[0103] In the fourth embodiment, the first beads 300 are arranged so that their protruding heights (D) from the first side surface portion 220 gradually increase, thereby preventing excessive inflow of cooling air toward the first cell module assembly 100 corresponding to the first first bead 300, and achieving the effect of efficiently dispersing the cooling air and reducing temperature deviation. The other configurations are the same as those of the first bead 300 in the first embodiment.

[0104] FIG. 12 is a diagram showing the results of a temperature distribution simulation using CFD (Computational Fluid Dynamics) to replicate the temperature deviation in the battery pack 1000 according to the fourth embodiment.

[0105] In this example, the temperature distribution showed the smallest temperature deviation per CP (2.5 / 3.37) compared to a general battery pack without beads, as shown in Table 1 below, indicating a 70% / 42% reduction in temperature deviation.

[0106] In this embodiment, the first bead 300 is provided only on the first side surface portion 220, but in other embodiments, the second bead 350 may also be provided on the second side surface portion 210, and the second beads 350 provided on the second side surface portion 210 may be arranged to correspond to each of the three cell module assemblies 100 adjacent to the exhaust port 202. At this time, the protruding height of the second bead 350 from the second side portion 210 is formed so as to gradually decrease in the direction opposite to the movement direction of the cooling air from the exhaust port 202, and the protruding height of the first second bead 350 closest to the exhaust port 202 from the second side portion 210 is within approximately 60±5% of the distance between the second side portion 210 and the other end (front plate 110) of the cell module assembly 100, the protruding height of the second second bead 350 is within approximately 40±5% of the distance between the second side portion 210 and the other end (front plate 110) of the cell module assembly 100, and the protruding height of the third second bead 350 is within approximately 20±5% of the distance between the second side portion 210 and the other end (front plate 110) of the cell module assembly 100.

[0107] Next, a battery pack 1000 in which temperature deviation is improved according to a fifth embodiment of the present invention will be described.

[0108] FIG. 13 is a detailed view showing a part of a battery pack according to a fifth embodiment of the present invention.

[0109] The battery pack 1000 according to the fifth embodiment of the present invention differs from the above-described embodiments in that the planar shape of the first bead 300 (or the second bead 350) is different. That is, while the first bead 300 (or the second bead 350) in the above-described embodiments has a trapezoidal cross section, the battery pack 1000 according to the fifth embodiment has a triangular cross section.

[0110] As shown in FIG. 13, the first bead 300 (or the second bead 350) includes a first inclined surface portion 301a bent from the first side surface portion 220, and a second inclined surface portion 301b bent from the first inclined surface portion 301a and connected to the first side surface portion 220.

[0111] In the first bead 300, the inclination angle of the first inclined surface portion 301a relative to the first side surface portion 220 is an obtuse angle, specifically within a range of 130 degrees to 140 degrees, or may be around 135 degrees. That is, the inclination angle of the first inclined surface portion 301a is within a range of 40 degrees to 50 degrees, or around 45 degrees, relative to an imaginary line connecting the first inclined surface portion 301a and the second inclined surface portion 301b, which are separated from each other.

[0112] Second inclined surface portion 301b is bent from an end portion of first inclined surface portion 301a and extends toward first side surface portion 220, and the end portion of second inclined surface portion 301b is connected to first side surface portion 220. The inclination angle of second inclined surface portion 301b with respect to first side surface portion 220 may be the same as that of first inclined surface portion 301a. That is, the inclination angle of second inclined surface portion 301b with respect to first side surface portion 220 forms an obtuse angle, specifically within a range of 130 degrees to 140 degrees, or around 135 degrees.

[0113] In this embodiment, the plurality of first beads 300 (or second beads 350) arranged on the first side surface portion 220 are formed so that the cross-sectional area of their planes gradually increases while maintaining a triangular shape from one end of the first side surface portion 220 adjacent to the air intake port 201 along the direction of movement of the cooling air. That is, the plurality of first beads 300 (or second beads 350) provided on the first side surface portion 220 have the same inclination angle of the first inclined surface portion 301a and the second inclined surface portion 301b, but are formed so that the protruding height (D) from the first side surface portion 220 gradually increases from one end of the first side surface portion adjacent to the air intake port 201 along the direction of movement of the cooling air as the cross-sectional area of their planes increases.

[0114] Specifically, the protruding height (D) of the first first bead 300 closest to the air intake port 201 from the first side surface portion 220 is within approximately 15% to 25% of the distance between the first side surface portion 220 and one end of the cell module assembly 100 (or the rear plate 120), the protruding height (D) of the second first bead 300 from the first side surface portion 220 is within approximately 35% to 45% of the distance between the first side surface portion 220 and one end of the cell module assembly 100 (or the rear plate 120), and the protruding height (D) of the third first bead 300 from the first side surface portion 220 is within approximately 55% to 65% of the distance between the first side surface portion 220 and one end of the cell module assembly 100 (or the rear plate 120).

[0115] In this embodiment, the first bead 300 (or the second bead 350) is arranged on the first side surface portion 220 so as to face the space between the cell module assemblies 100, and is provided in the area where an extension line of the space between the two cell module assemblies 100 contacts the first side surface portion 220. In this way, by arranging the first bead 300 on the first side surface portion 220 so as to face the space between the cell module assemblies 100, cooling air can be smoothly guided into the space between the cell module assemblies 100.

[0116] In this embodiment, the cooling air flowing in from the air intake port 201 moves linearly, but moves along the first inclined surface portion 301a and is guided into the space between the cell module assemblies 100. Note that, although Fig. 13 shows the first beads 300 spaced equally apart, the distance between the first first bead 300 and the second first bead 300 may be longer than the distance from the air intake port 201 to the first first bead.

[0117] [Test example] In order to confirm the effect of reducing temperature deviation according to the present invention, a temperature distribution simulation was carried out using CFD (Computational Fluid Dynamics), and the results are shown in FIGS.

[0118] FIG. 14 is a diagram showing various examples of the present invention and comparative examples, FIG. 15 is a diagram showing the temperature distribution of the test example shown in FIG. 14, and FIG. 16 is a graph showing the flow rate of each cell module assembly in the test example shown in FIG. 14.

[0119] FIG. 14 shows examples of bead application arrangements for performing temperature distribution simulations. Case #1 is a general battery pack not provided with beads according to the present invention. Case #2 is a battery pack in which three beads are arranged on the first side surface according to the first embodiment of the present invention, each with a protruding height of 15 mm. Case #3 is a battery pack in which three beads are arranged on the first side surface according to the first embodiment of the present invention, each with a protruding height of 7.5 mm. Case #4 is a battery pack in which three beads are arranged on the first side surface according to the fourth embodiment of the present invention. Case #5 is a battery pack according to the third embodiment of the present invention, in which three beads are arranged on each of the first and second side portions, with the protruding heights of the beads being 7.5 mm each; and Case #6 is a battery pack according to the fourth embodiment of the present invention, in which three beads are arranged on the first side portion, with the protruding heights of the beads being 5 mm, 10 mm, and 15 mm each, and three beads are arranged on the second side portion, with the protruding heights being 5 mm, 10 mm, and 15 mm each.

[0120] Tables 1 and 2 below show the results of a temperature distribution simulation performed for each case in FIG.

[0121] [Table 1]

[0122] [Table 2]

[0123] Table 1 shows the maximum and minimum temperatures for each case when 25°C cooling air is injected, for a heat source temperature of 0.25 CP (1 cp is the power that can buffer the battery for 1 hour), and Table 2 shows the maximum and minimum temperatures for each heat source temperature of 0.5 CP. Compared to the conventional case (Case #1), the temperature deviation was reduced in all of the cases according to the present invention (Cases #2 to #6), and the smallest temperature deviation was confirmed in Case #4.

[0124] In addition, Table 3 and Figure 16 show the inflow flow rate for each case in the cell module assembly 100, where CMA#6 to #1 refer to cell module assemblies 100 arranged in order from the air intake port 201 to the exhaust port 202, with CMA#6 being the cell module assembly 100 closest to the air intake port 201 and CMA#1 being the cell module assembly 100 closest to the exhaust port 202.

[0125] It can be seen that in CMA#6, the cell module assembly 100 closest to the air intake port 201, the inflow flow rate generally increases the closer it is to the exhaust port 202, and that CMA#1, the cell module assembly 100 closest to the exhaust port 202, shows the greatest inflow flow rate.

[0126] Also, it can be seen that the flow rate deviation is reduced in the battery packs according to the present invention (Cases #2 to #6) compared to Case #1, which is a general battery pack not provided with the beads of the present invention.

[0127] [Table 3]

[0128] In the battery pack according to the present invention, the temperature deviation is minimized as described above, thereby improving the battery life, and thus the battery performance and safety of the battery operation can be ensured.

[0129] Although the present invention has been described in detail above by way of preferred embodiments, it is not limited to the above-described embodiments, and various changes and modifications can be made by a person having ordinary skill in the art to which the present invention pertains, without departing from the spirit of the present invention. [Industrial Applicability]

[0130] According to the present invention, the temperature difference between battery cell assemblies in a battery pack is improved, and thus it is possible to provide a battery pack with improved battery performance and battery life. [Explanation of symbols]

[0131] 100 Cell Module Assembly (CMA) 100 cell module assembly 110 Front plate 111 Opening 120 Rear plate 200 cases 201 Air supply port 202 Exhaust port 205 Inflow passage 206 Outflow Transfer Passage 210 Second side part 220 first side portion 230 Third side part 240 Fourth Side 250 Top part 260 Bottom part 300 First Bead 300a Slope section 300b protruding end 301a first inclined surface portion 301b Second slope section 350 Second Bead 1000 battery packs

Claims

1. a plurality of cell module assemblies; and a case for accommodating the cell module assembly; A battery pack in which temperature deviation is improved, comprising: The case is an air intake port through which cooling air flows from the case; an exhaust port through which cooling air is exhausted from the case; and a first side portion disposed on one side of the case; Including, The battery pack having improved temperature deviation, wherein the first side portion includes a plurality of first beads protruding from the first side portion toward the inside of the case.

2. The battery pack according to claim 1 , wherein the case further includes a second side surface disposed opposite the first side surface.

3. an inflow passage provided inside the first side surface portion of the case, through which the cooling air flowing in from the air intake port flows; and an outflow passage provided inside the second side surface portion of the case, through which the cooling air flows so that the cooling air is discharged from the exhaust port; The battery pack with improved temperature deviation according to claim 2 , further comprising:

4. The case is a third side portion disposed on the other side of the case; and a fourth side portion disposed opposite the third side portion; The battery pack with improved temperature deviation according to claim 2 , further comprising:

5. 5. The battery pack according to claim 4, wherein the air inlet is provided in the third side surface portion, and the air outlet is provided in the fourth side surface portion.

6. The battery pack with improved temperature deviation according to claim 4 , wherein the plurality of cell module assemblies are arranged along a direction from the third side surface portion to the fourth side surface portion.

7. 7. The battery pack with improved temperature deviation according to claim 1, wherein the first bead is formed so that the entire thickness of the first side portion protrudes toward the inside of the case.

8. The battery pack with improved temperature deviation according to claim 1 , wherein the first bead is disposed on the first side surface so as to face a space between the cell module assembly and the first bead.

9. The battery pack with improved temperature deviation according to claim 1 , wherein the first bead has a trapezoidal cross section.

10. 6. The battery pack according to claim 5, wherein the first bead is positioned within half the length of the first side portion from one end of the first side portion connected to the third side portion.

11. 11. The battery pack with improved temperature deviation according to claim 10, wherein the number of the first beads is equal to or less than half the number of the cell module assemblies.

12. The battery pack with improved temperature deviation according to claim 1 , wherein the first bead has a triangular cross section.

13. 2. The battery pack according to claim 1, wherein the protruding height of the plurality of first beads from the first side portion gradually increases along the direction of movement of the cooling air flowing in from the air intake port.

14. A battery pack with improved temperature deviation as described in claim 13, wherein the protruding height from the first side surface of the first bead from the air inlet is 15% to 25% of the distance between the first side surface and one end of the cell module assembly, the protruding height from the second first bead from the air inlet is 35% to 45% of the distance between the first side surface and one end of the cell module assembly, and the protruding height from the third first bead from the air inlet is 55% to 65% of the distance between the first side surface and one end of the cell module assembly.

15. 2. The battery pack according to claim 1, wherein the first bead has a vertical height at the first side portion that gradually increases along the direction of movement of the cooling air flowing in from the air inlet.

16. 3. The battery pack with improved temperature deviation according to claim 2, wherein the second side portion includes a plurality of second beads protruding from the second side portion toward the inside of the case.

17. The case is a third side portion disposed on the other side of the case; and a fourth side portion disposed opposite the third side portion; further comprising 17. The battery pack with improved temperature deviation according to claim 16, wherein the second beads are arranged to correspond to the cell module assemblies in order from the cell module assemblies adjacent to the fourth side surface portion.

18. 18. The battery pack with improved temperature deviation according to claim 17, wherein the protruding height of the second bead from the second side portion gradually decreases along a direction opposite to a moving direction of the cooling air from the exhaust port.

19. 19. The battery pack with improved temperature deviation described in claim 18, wherein the second bead is positioned within 1 / 2 of the length of the second side portion from one end of the second side portion connected to the fourth side portion.

20. 20. The battery pack with improved temperature deviation according to claim 19, wherein the number of the second beads is equal to or less than half the number of the cell module assemblies.

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