Battery pack and method for manufacturing battery pack

Abstract

A battery pack (10) is provided with: a battery cell (102); a left cover (112) and a right cover (114) thermally coupled with a given portion of the battery cell (102); and a filler (150) thermally coupled with other given portions of the battery cells (102). The closer to the given portion of the battery cell (102) the amount of at least a portion of the filler (150) decreases.

Description

Technical Field

[0001] The present invention relates to a battery pack and a method for manufacturing the battery pack. Background Art

[0002] In recent years, various battery packs have been developed that include multiple battery modules. For example, in the battery module described in Patent Document 1, the battery module is fixed to a housing. In this battery module, a heat conduction member is provided between the battery module and the housing. The heat conduction member is formed by coating.

[0003] Patent Document 2 describes a method for bonding battery cells to each other using an adhesive. In this method, the adhesive is provided in a stripe pattern parallel to the longitudinal direction of the battery cells.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2017 / 47211

[0007] Patent Document 2: Japanese Patent Application Laid-Open No. 2006-172994 Summary of the Invention

[0008] -Problems to be solved by the invention-

[0009] Battery cells mounted in a container via fillers may also be thermally coupled to heat-conducting elements other than the fillers. The fillers are sometimes evenly spaced relative to the battery cells. Consequently, heat is evenly transferred from the battery cells via the fillers, and evenly transferred to the battery cells via the fillers. However, in this case, the temperature distribution of the battery cells may vary due to heat transfer from the battery cells to the heat-conducting elements and from the heat-conducting elements to the battery cells. This variation in the temperature distribution of the battery cells may affect the characteristics of the battery cells.

[0010] One example of an object of the present invention is to suppress variations in temperature distribution of battery cells. Other objects of the present invention will become apparent from the description of this specification.

[0011] -Methods for solving the problem-

[0012] One embodiment of the present invention is as follows.

[0013] [1] A battery pack comprising: a battery cell; a heat conduction element thermally coupled to a given portion of the battery cell; and a filler thermally coupled to another given portion of the battery cell, wherein the amount of at least a portion of the filler decreases as the filler approaches the given portion of the battery cell.

[0014] [2] The battery pack according to [1], wherein the heat conduction element is located on at least one of both sides of the plurality of battery cells stacked in a given direction.

[0015] [3] A method for manufacturing a battery pack, characterized by comprising the following steps: a step of thermally coupling a given portion of a battery cell to a heat conduction element; and a step of thermally coupling another given portion of the battery cell to a filler, wherein the amount of at least a portion of the filler decreases as the filler approaches the given portion of the battery cell.

[0016] -Effects of the Invention-

[0017] According to the above aspect of the present invention, it is possible to suppress variations in temperature distribution among battery cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a perspective view of a battery pack according to an embodiment.

[0019] Figure 2 This is a plan view of a battery pack according to the embodiment with the upper case removed.

[0020] Figure 3 It is a plan view of a battery module according to the embodiment.

[0021] Figure 4 yes Figure 3 AA cross-sectional view.

[0022] Figure 5 It is a top view of the filler according to the embodiment.

[0023] Figure 6 It is a diagram for explaining a first example of a method for forming a filler according to an embodiment.

[0024] Figure 7 It is a diagram for explaining a second example of the method for forming the filler according to the embodiment.

[0025] Figure 8 It is a diagram for explaining a third example of the method for forming the filler according to the embodiment.

[0026] Figure 9 It is a diagram for explaining a fourth example of the method for forming the filler according to the embodiment. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present invention will be described using the accompanying drawings. In all the drawings, the same components are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

[0028] Hereinafter, "A and B are thermally coupled to each other" means, for example, that A and B are in direct contact with each other or that A and B are bonded to each other via a thermally conductive adhesive or other element having a thermal conductivity of 10 W / m·K or greater, for example, 100 W / m·K or greater. However, thermal coupling between A and B is not limited to this example.

[0029] A and B being thermally insulated from each other means that, for example, an element such as air having a thermal conductivity of less than 0.50 W / m·K, for example, less than 0.10 W / m·K exists between A and B. However, thermal insulation between A and B is not limited to this example.

[0030] Figure 1 It is a perspective view of the battery pack 10 according to the embodiment. Figure 2 This is a plan view of the battery pack 10 according to the embodiment in a state where the upper case 220 is removed.

[0031] In the embodiment, the battery pack 10 is mounted in an automobile. Specifically, the battery pack 10 is mounted between the front and rear wheels of the automobile. Unless otherwise specified, the following description assumes that the battery pack 10 is mounted in an automobile. However, the battery pack 10 can also be used in applications other than automobiles.

[0032] In each figure, the X direction, Y direction, and Z direction are shown for illustration. The X direction indicates the front-back direction of the battery pack 10. The Y direction is perpendicular to the X direction. The Y direction indicates the left-right direction of the battery pack 10. The Z direction is perpendicular to both the X direction and the Y direction. The Z direction indicates the up-down direction of the battery pack 10. The arrows indicating the X direction, the Y direction, and the Z direction indicate the front direction, the left direction, and the up direction of the battery pack 10, respectively. Figure 2 In the figure, the white circle with a black dot indicating the Z direction indicates that the arrow indicating the Z direction extends from the back to the front of the paper. However, the relationship between the X direction, Y direction, and Z direction and the front-back direction, left-right direction, and up-down direction of the battery pack 10 is not limited to this example.

[0033] In the embodiment, the front-to-back direction, left-to-right direction, and vertical direction of the battery pack 10 are determined by the vehicle in which the battery pack 10 is mounted. The X, Y, and Z directions represent the front-to-back direction, left-to-right direction, and vertical direction of the vehicle, respectively. The arrows indicating the X, Y, and Z directions represent the front, left, and top directions of the vehicle, respectively. However, the relationship between the front-to-back direction, left-to-right direction, and vertical direction of the battery pack 10 and the front-to-back direction, left-to-right direction, and vertical direction of the vehicle is not limited to this example.

[0034] Hereinafter, the direction perpendicular to the Z direction will be referred to as a horizontal direction as needed.

[0035] The battery pack 10 includes four battery modules 100 and a housing 200. The four battery modules 100 include a pair of battery modules 100 on the left side arranged in the X-direction and a pair of battery modules 100 on the right side arranged in the X-direction. The housing 200 includes a lower housing 210 and an upper housing 220. The lower housing 210 is sometimes generally referred to as a tray or a main body. The lower housing 210 includes a lower plate 212 and side frames 214. The upper housing 220 is sometimes generally referred to as a cover or a lid. As described later, each battery module 100 includes a plurality of battery cells 102.

[0036] A pair of terminals 104 are provided in front of the side frame 214. The pair of terminals 104 are arranged substantially parallel to each other in the Y direction. The front end of each terminal 104 protrudes forward from the front surface of the side frame 214. In the electrical path, the four battery modules 100 are connected in series between the pair of terminals 104.

[0037] The lower case 210 and the upper case 220 are attached to each other via a sealing material 230. The lower case 210, the upper case 220, and the sealing material 230 form a housing space 250. The housing space 250 houses four battery modules 100.

[0038] The lower plate 212 defines the bottom of the storage space 250. The side frames 214 define the sides of the storage space 250. Specifically, when viewed from the Z direction, the side frames 214 are provided along the outermost periphery of the lower plate 212. The upper housing 220 defines the top of the storage space 250.

[0039] The sealing material 230 is, for example, an elastic material such as rubber. The sealing material 230 is provided along the entire circumference of the side frame 214 as viewed in the Z direction. Thus, the sealing material 230 surrounds the storage space 250 as viewed in the Z direction. Therefore, the sealing material 230 can seal the storage space 250 from the space outside the storage body 200.

[0040] The number and arrangement of the battery modules 100 are not limited to the examples described in the embodiment. For example, the number of the battery modules 100 may be only two, only three, or five or more.

[0041] Figure 3 It is a plan view of the battery module 100 according to the embodiment. Figure 4 yes Figure 3 AA cross-sectional view. Figure 5 FIG is a top view of the filler 150 according to the embodiment. Figure 4 In the figure, a white circle with an X indicating the X direction indicates that an arrow indicating the X direction extends from the front to the back of the paper.

[0042] like Figure 4As shown, the battery module 100 includes a cell stack 102G and a housing case 110 .

[0043] The cell stack 102G includes a plurality of battery cells 102. Figure 4 In the example shown, a plurality of battery cells 102 are stacked approximately in parallel in the Y direction. A material not shown in the figure having a given thermal conductivity is provided between the battery cells 102 adjacent to each other in the Y direction. Polyurethane is exemplified as a material having a given thermal conductivity, but is not limited thereto. Alternatively, the battery cells 102 adjacent to each other in the Y direction are in direct contact with each other. Therefore, the plurality of battery cells 102 are thermally coupled to each other. Furthermore, the plurality of battery cells 102 are electrically connected to each other. For example, in the cell stack 102G, a plurality of battery cell groups including a plurality of battery cells 102 connected in parallel are connected in series. Alternatively, a plurality of single battery cells 102 may also be connected in series.

[0044] The storage case 110 stores the cell stack 102G and includes a left cover 112, a right cover 114, a lower cover 116, an upper cover 118, a front cover (not shown), and a rear cover (not shown).

[0045] Left cover 112 covers the left side of cell stack 102G. The right side of left cover 112 contacts the left side of battery cell 102 located at the left end of cell stack 102G, either directly or through the aforementioned material having a predetermined thermal conductivity. Left cover 112 is made of a material with a relatively high thermal conductivity. Therefore, left cover 112 serves as a heat conducting element thermally coupled to cell stack 102G.

[0046] Right cover 114 covers the right side of cell stack 102G. The right side of left cover 112 contacts the left side of battery cell 102 located at the left end of cell stack 102G, either directly or through the aforementioned material having a predetermined thermal conductivity. Left cover 112 is made of a material with a relatively high thermal conductivity. Therefore, left cover 112 serves as a heat conducting element thermally coupled to cell stack 102G.

[0047] The lower cover 116 covers the lower surface of the cell stack 102G via a thermally conductive adhesive 116a. Therefore, the lower surface of the cell stack 102G and the upper surface of the lower cover 116 are thermally coupled via the thermally conductive adhesive 116a.

[0048] The upper cover 118 covers the upper surface of the single-unit stack 102G with a gap therebetween. Therefore, the upper surface of the single-unit stack 102G and the upper cover 118 are thermally insulated.

[0049] The front cover (not shown) covers the front surface of the single body stack 102G with a gap therebetween. Therefore, the front surface of the single body stack 102G and the rear surface of the front cover are thermally insulated.

[0050] The rear cover (not shown) covers the rear surface of the single body stack 102G with a gap therebetween, so that the rear surface of the single body stack 102G and the front surface of the rear cover are thermally insulated.

[0051] The lower plate 212 includes an upper cooling plate 212a and a lower cooling plate 212b. The upper cooling plate 212a and the lower cooling plate 212b are each made of metal, for example. Specifically, the upper cooling plate 212a and the lower cooling plate 212b are primarily composed of aluminum, for example. The upper cooling plate 212a and the lower cooling plate 212b overlap in the Z direction. A refrigerant 212c flows between the lower surface of the upper cooling plate 212a and the upper surface of the lower cooling plate 212b. The refrigerant 212c is, for example, a liquid such as water.

[0052] The lower housing 210 includes a support frame 216. When viewed from the Z direction, the support frame 216 forms a surrounding body that surrounds at least a portion of the monomer stack 102G. The support frame 216 is provided on the upper surface of the upper cooling plate 212a. The lower surface of the support frame 216 and the upper surface of the upper cooling plate 212a are thermally coupled to each other. Hereinafter, as needed, the portion of the support frame 216 located on the left side of the monomer stack 102G is referred to as the left support portion 216a. Hereinafter, as needed, the portion of the support frame 216 located on the right side of the monomer stack 102G is referred to as the right support portion 216b.

[0053] A left protrusion 122 is provided on the left outer side surface of the left cover 112. The left side surface of the left cover 112 and the right end portion of the left protrusion 122 are thermally coupled to each other. The left protrusion 122 protrudes toward the left side of the left cover 112. The left protrusion 122 is arranged on the upper surface of the left support portion 216a. The left protrusion 122 and the left support portion 216a are fastened to each other by a plurality of left bolts 162. Therefore, the lower surface of the left protrusion 122 and the upper surface of the left support portion 216a are in contact with each other and are thermally coupled to each other. Figure 3 As shown, the plurality of left bolts 162 are arranged substantially parallel to the X direction. However, the number and arrangement of the left bolts 162 are not limited to Figure 3 For example, the left protrusion 122 and the left support portion 216a may be fastened to each other by only a single left bolt 162.

[0054] A right protrusion 124 is provided on the right outer side surface of the right cover 114. The right side surface of the right cover 114 and the left end portion of the right protrusion 124 are thermally coupled to each other. The right protrusion 124 protrudes toward the right side of the right cover 114. The right protrusion 124 is arranged on the upper surface of the right support portion 216b. The right protrusion 124 and the right support portion 216b are fastened to each other by a plurality of right bolts 164. Therefore, the lower surface of the right protrusion 124 and the upper surface of the right support portion 216b are in contact with each other and are thermally coupled to each other. Figure 3As shown, a plurality of right bolts 164 are arranged substantially in parallel in the X direction. However, the number and arrangement of the right bolts 164 are not limited to Figure 3 For example, the right protrusion 124 and the right support portion 216b may be fastened to each other by only a single right bolt 164.

[0055] The battery module 100 is mounted on the lower plate 212 via the filler 150. The filler 150 is disposed between the lower surface of the lower cover 116 and the upper surface of the upper cooling plate 212a. The filler 150 is compressed in the Z direction by the lower surface of the lower cover 116 and the upper surface of the upper cooling plate 212a.

[0056] In an embodiment, the filler 150 is a thermally conductive adhesive. Examples of the filler 150 include a modified silicone-based coated filler, a polyurethane-based coated filler, and an acrylic-based coated filler. Therefore, the lower surface of the lower cover 116 and the upper surface of the upper cooling plate 212a are physically joined via the filler 150. Therefore, compared to a case where the filler 150 is not provided, the lower cover 116 and the upper cooling plate 212a can be made less likely to deviate from each other. Furthermore, the lower surface of the lower cover 116 and the upper surface of the upper cooling plate 212a are thermally coupled via the filler 150. Therefore, compared to a case where the filler 150 is not provided, the heat generated in the battery module 100 is easily conducted to the lower shell 210 via the thermally conductive adhesive 116a, the lower cover 116, and the filler 150.

[0057] like Figure 5 As shown, when viewed from the Z direction, the pattern of the filler 150 is formed by Figure 6 as well as Figure 7 The exemplified substantially sawtooth pattern, the Figure 8 as well as Figure 9 The filler 150 is applied in a substantially stripe pattern as shown, and is compressed in the Z direction and extended in the horizontal direction. The filler 150 is compressed in the Z direction by the lower surface of the lower cover 116 and the upper surface of the upper cooling plate 212a.

[0058] like Figure 5 As shown, the filler 150 includes a wide area 152, a first narrow area 154, and a second narrow area 156. The width of the wide area 152 in the X direction is wider than the width of each of the first narrow area 154 and the second narrow area 156 in the X direction. Figure 5In the example shown, the widths of the first narrow region 154 and the second narrow region 156 in the X direction are substantially equal. However, the widths of the first narrow region 154 and the second narrow region 156 in the X direction may differ. The wide region 152 is located between the first narrow region 154 and the second narrow region 156 in the Y direction. The first narrow region 154 is located to the left of the wide region 152. The second narrow region 156 is located to the right of the wide region 152.

[0059] The closer to the left end of the cell stack 102G in the Y direction, the smaller the X-direction width of the left half of the filler 150 from the wide region 152 to the first narrow region 154. That is, the closer to the left end of the cell stack 102G in the Y direction, the smaller the amount of filler 150 from the wide region 152 to the first narrow region 154. The closer to the right end of the cell stack 102G in the Y direction, the smaller the X-direction width of the right half of the filler 150 from the wide region 152 to the second narrow region 156. That is, the closer to the right end of the cell stack 102G in the Y direction, the smaller the amount of filler 150 from the wide region 152 to the second narrow region 156. Therefore, compared to a case where the amount of filler 150 is constant regardless of its position in the Y direction within the filler 150, variations in the temperature distribution of the cell stack 102G can be suppressed. The reason is as follows.

[0060] First, the conduction of heat generated from the single-unit stack 102G to the lower case 210 will be examined.

[0061] Heat generated from the cell stack 102G is primarily conducted from the lower surface of the cell stack 102G via the thermally conductive adhesive 116a, the lower cover 116, and the filler 150 to the upper surface of the lower housing 210. Furthermore, the left and right sides of the cell stack 102G are thermally coupled to the left cover 112 and the right cover 114, respectively. Therefore, some of the heat generated from the cell stack 102G may be conducted from the left side of the cell stack 102G via the left cover 112, the left protrusion 122, and the left support 216a to the left side of the lower plate 212, while also being conducted from the right side of the cell stack 102G via the right cover 114, the right protrusion 124, and the right support 216b to the right side of the lower plate 212. However, the front and rear surfaces of the cell stack 102G are thermally insulated from the front and rear covers, respectively, which are not shown. Therefore, when heat conduction from the cell stack 102G in the Z direction is not considered, heat is more easily conducted in the Y direction than in the X direction within the cell stack 102G. Therefore, if heat is uniformly conducted from the lower surface of the cell stack 102G, the temperature at both ends of the cell stack 102G in the Y direction is likely to be lower than the temperature at the center of the cell stack 102G in the Y direction.

[0062] In the embodiment, the amount of filler 150 is locally reduced in the region that overlaps with both ends of the cell stack 102G in the Y direction in the Z direction. Therefore, heat conduction from the cell stack 102G via the filler 150 is suppressed at both ends of the cell stack 102G in the Y direction compared to the center of the cell stack 102G in the Y direction. Consequently, compared to a case where the amount of filler 150 is constant regardless of the position in the Y direction within the filler 150, variations in the temperature distribution of the cell stack 102G can be suppressed.

[0063] Next, the conduction of heat generated from the lower case 210 to the single-unit stack 102G will be examined.

[0064] Heat generated from the lower plate 212 is primarily conducted from the upper surface of the lower plate 212 via the filler 150, the lower cover 116, and the thermally conductive adhesive 116a toward the lower surface of the cell stack 102G. Furthermore, some of the heat generated from the lower plate 212 is sometimes conducted from the left side of the lower plate 212 via the left support 216a, the left protrusion 122, and the left cover 112 toward the left side of the cell stack 102G, and from the right side of the lower plate 212 via the right support 216b, the right protrusion 124, and the right cover 114 toward the right side of the cell stack 102G. However, for the same reasons as above, if heat conduction in the Z direction of the cell stack 102G is not considered, heat is more easily conducted in the Y direction than in the X direction within the cell stack 102G. Therefore, if heat is uniformly conducted to the lower surface of the cell stack 102G, the temperature at both ends of the cell stack 102G in the Y direction tends to be higher than the temperature at the center of the cell stack 102G in the Y direction.

[0065] In the embodiment, the amount of filler 150 is locally reduced in the region that overlaps with both ends of the cell stack 102G in the Y direction. Therefore, heat conduction to the cell stack 102G via the filler 150 is suppressed at both ends of the cell stack 102G in the Y direction, compared to the center of the cell stack 102G in the Y direction. Consequently, compared to a case where the amount of filler 150 is constant regardless of the position in the Y direction within the filler 150, variations in the temperature distribution of the cell stack 102G can be suppressed.

[0066] The amount of filler 150 to be reduced can be determined based on which portion of the cell stack 102G is thermally coupled to the heat conduction element. In the embodiment, the left and right sides of the cell stack 102G are thermally coupled to the left cover 112 and the right cover 114, respectively, which function as heat conduction elements. Therefore, the amount of filler 150 on the left and right sides is smaller than the amount of filler 150 in the center portion in the Y direction. However, if the left side of the cell stack 102G is thermally coupled to the heat conduction element and the right side of the cell stack 102G is thermally insulated, the amount of filler 150 on the left side can be smaller than the amount of filler 150 in the rest of the cell stack 102G. In this example, compared to a case where the amount of filler 150 is constant regardless of the position in the Y direction within the cell stack 150, variations in the temperature distribution of the cell stack 102G can be suppressed. Alternatively, the left and right sides of the cell stack 102G may be thermally insulated, and the front and rear surfaces of the cell stack 102G may be thermally coupled to the heat conducting element. In this case, the amount of filler 150 in the front and rear portions may be smaller than the amount of filler 150 in the center portion in the X direction. In this example, compared to a case where the amount of filler 150 is constant regardless of the X-direction position within the filler 150, variations in the temperature distribution of the cell stack 102G can be suppressed.

[0067] In the embodiment, the amount of each portion of the filler 150 is adjusted by the horizontal width of each portion of the filler 150. However, the amount of each portion of the filler 150 can also be adjusted by the Z-direction thickness of each portion of the filler 150. In this example, the thicker the Z-direction thickness of the filler 150, the greater the amount of the filler 150, and the thinner the Z-direction thickness of the filler 150, the less the amount of the filler 150.

[0068] In the embodiment, the lower surface of the cell stack 102G and both side surfaces in the Y direction of the cell stack 102G are thermally coupled to the same heat conducting element, the lower plate 212. However, the lower surface of the cell stack 102G and both side surfaces in the Y direction of the cell stack 102G may be thermally coupled to different heat conducting elements.

[0069] Figure 6 1 is a diagram for explaining a first example of a method for forming the filler 150 according to the embodiment. In this first example, the filler 150 is formed as follows.

[0070] First, a coating filler 150A is applied to the upper surface of the upper cooling plate 212a from a nozzle (not shown). The coating filler 150A includes a first pattern portion 152A, a second pattern portion 154A, and a third pattern portion 156A. The first pattern portion 152A is located between the second pattern portion 154A and the third pattern portion 156A in the Y direction. The second pattern portion 154A is located to the right of the first pattern portion 152A. The third pattern portion 156A is located to the left of the first pattern portion 152A.

[0071] The first pattern portion 152A, the second pattern portion 154A, and the third pattern portion 156A are each substantially zigzag-shaped and include a plurality of folded portions TA alternately arranged on both sides of the center of the single laminate 102G in the X direction.

[0072] The width of the first pattern portion 152A in the X direction is wider than the width of each of the second pattern portion 154A and the third pattern portion 156A in the X direction. The width of each pattern of the filler 150A in the X direction refers to the distance between the folded portions TA on both sides of each pattern in the X direction.

[0073] Next, the battery module 100 is mounted on the upper surface of the upper cooling plate 212a via the applied filler 150A. Next, the left protrusion 122 and the left support portion 216a are fastened to each other using the left bolt 162. Similarly, the right protrusion 124 and the right support portion 216b are fastened to each other using the right bolt 164. As a result, the applied filler 150A is compressed in the Z direction by the lower surface of the lower cover 116 and the upper surface of the upper cooling plate 212a. Therefore, the applied filler 150A extends in the horizontal direction. Therefore, the gaps between the folded portions TA of each pattern of the applied filler 150A are filled with filler to form the filler 150. The wide area 152 corresponds to the first pattern portion 152A. The first narrow area 154 corresponds to the second pattern portion 154A. The second narrow area 156 corresponds to the second narrow area 156.

[0074] Figure 7 1 is a diagram for explaining a second example of a method for forming the filler 150 according to the embodiment. Figure 7 The second example described is the same as the one using Figure 6 The first example is the same as described above.

[0075] Figure 7The illustrated coating filler 150B includes a first pattern portion 152B, a second pattern portion 154B, and a third pattern portion 156B. The first pattern portion 152B is located between the second pattern portion 154B and the third pattern portion 156B in the X-direction. The second pattern portion 154B is located forward of the first pattern portion 152B. The third pattern portion 156B is located rearward of the first pattern portion 152B.

[0076] The first pattern portion 152B, the second pattern portion 154B, and the third pattern portion 156B are each substantially zigzag-shaped and include folded portions TB alternately arranged on both sides of the center of the single laminate 102G in the Y direction.

[0077] The Y-direction width of the first pattern portion 152B is wider than the Y-direction widths of the second pattern portion 154B and the third pattern portion 156B. The Y-direction width of each pattern of the filler coating 150B refers to the Y-direction distance between the folded portions TB on both sides of each pattern. Therefore, the first pattern portion 152B includes a central region 152Ba, a left region 152Bb, and a right region 152Bc. The central region 152Ba is located in the region that overlaps with the second pattern portion 154B and the third pattern portion 156B in the X-direction. The left region 152Bb is located to the left of the central region 152Ba. The right region 152Bc is located to the right of the central region 152Ba.

[0078] and use Figure 6 Similarly to the first example described above, the applied filler 150B is compressed in the Z direction to form the filler 150. The wide region 152 corresponds to the central region 152Ba, the second pattern portion 154B, and the third pattern portion 156B. The first narrow region 154 corresponds to the left region 152Bb. The second narrow region 156 corresponds to the right region 152Bc.

[0079] Figure 8 1 is a diagram for explaining a third example of a method for forming the filler 150 according to the embodiment. Figure 8 The third example described is the same as the one using Figure 6 The first example is the same as described above.

[0080] Figure 8 The illustrated coating filler 150C includes a first pattern portion 152C, a second pattern portion 154C, and a third pattern portion 156C. The first pattern portion 152C is located between the second pattern portion 154C and the third pattern portion 156C in the Y direction. The second pattern portion 154C is located to the left of the first pattern portion 152C. The third pattern portion 156C is located to the right of the first pattern portion 152C.

[0081] The first pattern portion 152C, the second pattern portion 154C, and the third pattern portion 156C are formed in a substantially stripe shape. Each of the first pattern portion 152C, the second pattern portion 154C, and the third pattern portion 156C includes a plurality of linear portions LC extending substantially parallel to the X direction.

[0082] The width of the first pattern portion 152C in the X direction is greater than the width of each of the second pattern portion 154C and the third pattern portion 156C in the X direction. The width of each pattern of the filler coating 150C in the X direction refers to the length of the linear portion LC in the X direction of each pattern.

[0083] and use Figure 6 As in the first example described above, the applied filler 150C is compressed in the Z direction to form the filler 150. The wide area 152 corresponds to the first pattern portion 152C. The first narrow area 154 corresponds to the second pattern portion 154C. The second narrow area 156 corresponds to the third pattern portion 156C.

[0084] Figure 9 1 is a diagram for explaining a fourth example of a method for forming the filler 150 according to the embodiment. Figure 9 The fourth example described is the same as the one using Figure 6 The first example is the same as described above.

[0085] Figure 9 The illustrated coating filler 150D includes a first pattern portion 152D, a second pattern portion 154D, and a third pattern portion 156D. The first pattern portion 152D is located between the second pattern portion 154D and the third pattern portion 156D in the X-direction. The second pattern portion 154D is located forward of the first pattern portion 152D. The third pattern portion 156D is located rearward of the first pattern portion 152D.

[0086] The first pattern portion 152D, the second pattern portion 154D, and the third pattern portion 156D are substantially stripe-shaped and each includes a plurality of linear portions LD extending substantially parallel to the Y direction.

[0087] The Y-direction width of the first pattern portion 152D is greater than the Y-direction widths of the second pattern portion 154D and the third pattern portion 156D. The X-direction width of each pattern of the filler coating 150D refers to the Y-direction length of the linear portion LD of each pattern. Therefore, the first pattern portion 152D includes a central region 152Da, a left region 152Db, and a right region 152Dc. The central region 152Da is located in the X-direction overlapping region with the second pattern portion 154D and the third pattern portion 156D. The left region 152Db is located to the left of the central region 152Da. The right region 152Dc is located to the right of the central region 152Da.

[0088] and use Figure 6 Similarly to the first example described above, the applied filler 150D is compressed in the Z direction to form the filler 150. The wide region 152 corresponds to the central region 152Da, the second pattern portion 154D, and the third pattern portion 156D. The first narrow region 154 corresponds to the left region 152Db. The second narrow region 156 corresponds to the right region 152Dc.

[0089] As mentioned above, although embodiment of this invention was described with reference to drawings, these are illustrations of this invention, and various structures other than the above-mentioned can also be adopted.

[0090] This application claims priority based on Japanese Patent Application No. 2023-017107, filed on February 7, 2023, the entire disclosure of which is incorporated herein.

[0091] -Description of Reference Numerals-

[0092] 10: Battery pack, 100: Battery module, 102: Battery cell, 102G: Cell stack, 104: Terminal, 110: Housing, 112: Left cover, 114: Right cover, 116: Lower cover, 116a: Thermally conductive adhesive, 118: Upper cover, 122: Left protrusion, 124: Right protrusion, 150: Filler, 150A, 150B, 150C, 150D: Applied filler, 152: Wide area, 152A, 152B, 152C, 152D: First pattern portion, 152Ba, 152Da: Center area, 152Bb, 152Db: Left area, 152Bc, 152Dc: Right area Domain, 154: First narrow area, 154A, 154B, 154C, 154D: Second pattern portion, 156: Second narrow area, 156A, 156B, 156C, 156D: Third pattern portion, 162: Left bolt, 164: Right bolt, 200: Container, 210: Lower shell, 212: Lower plate, 212a: Upper cooling plate, 212b: Lower cooling plate, 212c: Refrigerant, 214: Side frame, 216: Support frame, 216a: Left support portion, 216b: Right support portion, 220: Upper shell, 230: Sealing material, 250: Container space, LC, LD: Linear portion, TA, TB: Folding portion.

Claims

1. A battery pack, characterized in that: have: Battery cells; a heat conducting element thermally coupled to a given portion of the battery cell; and a filler, thermally coupled to other given portions of the battery cell, The amount of at least a portion of the filler decreases closer to the given portion of the battery cell.

2. The battery pack according to claim 1, wherein: The heat conducting element is located on at least one of both sides of the plurality of battery cells stacked in a given direction.

3. A method for manufacturing a battery pack, characterized in that: It has the following processes: The step of thermally coupling a given portion of the battery cell to a heat conducting element; and a step of thermally coupling other given parts of the battery cell and the filler to each other, The amount of at least a portion of the filler decreases closer to the given portion of the battery cell.

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