Battery pack and method for manufacturing same

Abstract

The invention provides a battery pack and a manufacturing method thereof, which can maintain the battery capacity and the cooling function of a battery unit and improve the rigidity of a battery case. A battery pack (1) includes a battery case (10), a plurality of battery cells (20), and a plurality of refrigerant jackets (30), in which cell assemblies (20A) in which the plurality of battery cells (20) are joined in a row and the refrigerant jackets (30) are alternately arranged so as to be in surface contact with each other in a first direction, and each refrigerant jacket (30) is connected to refrigerant flow piping (40) provided on both sides in a second direction. At least a portion of the refrigerant jacket (30) is a reinforced plate-type refrigerant jacket (30R) configured such that the upper portions of both end portions in the second direction are extended and joined to the upper portions of the end plates (13, 14) of the battery case (10) while avoiding the refrigerant flow piping (40), thereby improving the rigidity of the battery case (10).

Description

Technical Field

[0001] The present invention relates to a battery pack for BEV (battery electric vehicle) and a method for manufacturing the same. Background Art

[0002] At present, battery packs for battery electric vehicles (BEVs) use the following module-to-pack (MTP) method: a plurality of units are bundled into a bundle to form a tightly bound battery module, and a plurality of the modules are mounted on a battery housing. In addition, a frame is provided on the battery housing along the width direction and the front-to-back direction of the vehicle to fix the module and help ensure the rigidity of the battery housing itself (for example, Patent Document 1). In addition, in order to cope with heat generation during charging and discharging, most battery cells have a water jacket for cooling (heating as needed) arranged under the module mounting portion, and temperature management is performed from the bottom surface of the battery cell.

[0003] It is required to increase the number of batteries due to the expansion of battery capacity or high voltage, but the area of ​​the vehicle body that can be used to carry batteries is limited. In the MTP method, there is a problem that the number of batteries carried is limited due to the space used by the structure of each module. Therefore, a cell-pack (Cell To Pack: CTP) method (for example, Patent Document 2, Patent Document 3) in which the cells are directly mounted in the battery housing is being studied. As one of the CTP methods, there is a method of densely mounting only battery cells in a frameless battery housing. In the above case, the amount of batteries carried can be increased, but the rigidity of the battery housing cannot be ensured, and the deflection near the center of the bottom surface of the housing becomes larger. Therefore, it is considered to provide a separated frame or ribs on the bottom surface, but if the frame is increased, the amount of batteries carried will be reduced, so a method of ensuring rigidity with a frame that is as thin as possible and as few in number is required. However, it is possible to set cooling parts on the bottom surface of the battery case, or there may be a busbar that electrically connects the units to each other when the terminals are set downward. Therefore, it is sometimes impossible to join the lower surface of the frame to the bottom surface in its entirety, and then use it as a path for wiring and piping between the side walls of the battery case. Therefore, it is considered that the end face of the frame cannot be joined to the wall in its entirety. On the other hand, as another CTP method, there is also a method of alternately and densely arranging battery cells and cooling parts connected to their sides. In the above case, a method of making the cooling parts function as a frame is considered, but similarly, in order to ensure the existence of the busbar or the path for wiring and piping, it is assumed that the bottom surface and the side cannot be joined in their entirety. Therefore, it is required to optimize the frame structure that can achieve the maximum rigidity improvement effect through the minimum connection with the battery case.

[0004] [Prior art literature]

[0005] [Patent Document]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2013-16467

[0007] [Patent Document 2] Japanese Patent Publication No. 2023-502274

[0008] [Patent Document 3] Japanese Patent Publication No. 2023-509695 Summary of the invention

[0009] [Problems to be solved by the invention]

[0010] The present invention has been made in view of the above-mentioned situation, and an object of the present invention is to improve the rigidity of a battery case while maintaining the battery capacity and the cooling function of a battery cell.

[0011] [Technical means to solve the problem]

[0012] The required number is estimated based on the trade-off between the rigidity improvement effect of the frame (thin plate) provided in the battery case and the space loss.

[0013] As a reference condition for calculating the optimal number of roots, the frame is set to be 8mm thick, and is set to be a rib that is not connected to the side frame (outer frame) of the battery case but is connected to the bottom plate on the entire surface. Based on the state without a frame, the displacement amount when the distributed load of the weight of the battery carried is applied to the bottom surface of the case is calculated through simulation. When the number of roots of the frame is increased, the point at which the displacement amount of the bottom surface decreases saturates is found. As a result, it can be said that the displacement amount can be greatly reduced by making 9 frames function.

[0014] Regarding the above tendency, the same is true in a simulation in which only a portion of the bottom surface is joined, which is closer to the actual state, but in the above case, the displacement increases. Therefore, in the present invention, a frame shape with protrusions on the upper part of both ends is adopted, so that it is connected to the upper part of the battery case side frame (outer frame) and they are connected, thereby greatly suppressing the displacement.

[0015] The battery pack 1 of the present invention comprises: a battery case 10, which extends in a first direction AA and a second direction BB that are orthogonal to each other and form a horizontal plane and is generally box-shaped; a plurality of battery cells 20, which are arranged in the battery case 10; and a plurality of refrigerant jackets 30, which have refrigerant passages 34 inside and cool the plurality of battery cells 20. The battery pack 1 is characterized in that the plurality of battery cells 20 constitute a unit assembly 20A in which a plurality of battery cells 20 are arranged in a row in the second direction BB and are joined together, and the unit assembly 20A and the refrigerant jacket 30 are connected in a row. The first direction AA is alternately arranged in a manner of surface contact with each other, and each of the refrigerant jackets 30 is connected to the refrigerant circulation pipes 40 arranged on both sides of the second direction BB. At least a part of the refrigerant jackets 30 is the following reinforced plate type refrigerant jacket 30R, which is constructed as follows: the upper parts of the two end parts in the second direction BB are extended in the second direction BB, while avoiding the refrigerant circulation pipes 40, and are connected to the upper parts of the end plates (13, 14) of the battery case 10 constituting the two end parts of the second direction BB, thereby improving the rigidity of the battery case 10.

[0016] With the above structure, the rigidity of the battery case can be increased and the deflection of the battery pack can be reduced while maintaining the number of battery cells mounted, the battery capacity, and the cooling function of the battery cells.

[0017] The configuration of the enhanced plate type refrigerant jacket 30R is determined by the relationship between the shell and the number of roots. Therefore, according to the size of the unit carried, one can be set in every three refrigerant jackets 30 arranged in the first direction AA, one can be set in every four refrigerant jackets 30 arranged in the first direction AA, or one can be set in every five refrigerant jackets 30 arranged in the first direction AA.

[0018] These structures can improve the rigidity of the battery case while maintaining the battery capacity and the cooling function of the battery cells.

[0019] The reinforcing plate type refrigerant jacket 30R may be disposed every 200 mm±20 mm in the first direction AA of the battery case.

[0020] With the above structure, the rigidity of the battery case can be improved while maintaining the battery capacity and the cooling function of the battery cells, when the actual battery case size is about 1500 mm to 2000 mm.

[0021] It is also preferable that the upper portion 30c of the reinforcing plate type refrigerant jacket 30R at both ends in the second direction BB is fitted into the cutouts (13a, 14a) provided in the end plates (13, 14) constituting both ends of the battery case 10 in the second direction BB.

[0022] With the above structure, the position of the reinforcing plate type refrigerant jacket is fixed, so in addition to the above effect, the position of each battery cell can be restricted.

[0023] The following structure can be preferably adopted: the refrigerant circulation piping 40 comprises: an inlet side socket 41 connected to one end 30a of the refrigerant jacket 30 in the second direction BB; and an outlet side socket 42 connected to the other end 30b of the refrigerant jacket 30 in the second direction BB, the inlet side socket 41 comprises: a one-side inlet piping 41a protruding from one side toward the first direction AA; and another-side inlet piping 41b protruding from the other side toward the first direction AA, the outlet side socket 42 comprises: a one-side outlet piping 42a protruding from one side toward the first direction AA protrudes in the first direction AA; and the other side outlet piping 42b protrudes from the other side toward the first direction AA, and is constructed as follows: when the two refrigerant jackets 30 are adjacent to each other with the unit assembly 20A clamped therebetween, the one side inlet piping 41a of the inlet side socket 41 connected to one refrigerant jacket 30 and the one side outlet piping 42a of the outlet side socket 42 are respectively connected to the other side inlet piping 41b of the inlet side socket 41 connected to the other refrigerant jacket 30 and the other side outlet piping 42b of the outlet side socket 42.

[0024] With the above structure, the unit assembly bodies are brought close to each other in a state where the inlet-side socket and the outlet-side socket are previously connected to each refrigerant jacket, so that the sockets are naturally connected to each other to form a refrigerant flow path, thereby improving assembly workability.

[0025] In addition, the manufacturing method of the battery pack of the present invention is a method for manufacturing a battery pack 1, wherein the battery pack 1 includes: a battery case 10, which extends in a first direction AA and a second direction BB that are orthogonal to each other and is roughly box-shaped; a plurality of battery cells 20, which are arranged in the battery case 10; and a plurality of refrigerant jackets 30, which have refrigerant passages 34 inside and cool the plurality of battery cells 20, and the method includes the following steps: arranging a plurality of the plurality of battery cells 20 in a row in the second direction BB and joining them to form a plurality of unit junctions 20A; arranging the unit junctions 20A and the refrigerant jackets 30 alternately in the first direction AA in the battery case 10 in a manner of surface contact with each other; and joining the upper portions of the two end portions of the second direction BB in at least a portion of the refrigerant jackets 30 to the upper portions of the end plates (13, 14) of the battery case 10 that constitute the two end portions of the second direction BB, thereby improving the rigidity of the battery case 10.

[0026] With this structure, the rigidity of the battery case can be improved while maintaining the battery capacity and the cooling function of the battery cells.

[0027] In addition, the symbols in the above parentheses are symbols representing the symbols of the corresponding components of the embodiments described later as an example of the present invention.

[0028] [Effects of the Invention]

[0029] The frame structure of the present invention can achieve both an increase in the amount of batteries mounted and a suppression of a reduction in the rigidity of the battery case, and can cope with an increase in the cruising range or a higher voltage of an electric vehicle.

[0030] In addition, in the present invention, by integrating the functions of the refrigerant jacket for cooling the battery side with the frame, the heat generated during charging can be greatly suppressed without reducing the battery loading capacity, and fast charging can be achieved. In addition, if a slit is formed in the side frame (outer frame) of the shell and a protrusion is embedded therein, not only can the rigidity be further improved, but the frame can also function as a function of restricting the battery position.

[0031] Furthermore, the method of joining only the upper part of a frame with a small number of roots has good disassembly properties because there are fewer connecting parts, which is suitable for resource recycling. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a perspective view schematically showing a battery pack according to the first embodiment of the present invention.

[0033] Figure 2 yes Figure 1 An enlarged perspective view of part C of the battery pack.

[0034] Figure 3 Yes Figure 2 A three-dimensional view in which the battery case is partially removed and a portion of the socket is removed and observed from the direction of arrow B.

[0035] Figure 4 It is a perspective view schematically showing a unit assembly.

[0036] Fig. 5(a) and Fig. 5(b) are perspective views schematically showing a refrigerant jacket, Fig. 5(a) is a general refrigerant jacket, and Fig. 5(b) is a reinforcing plate type refrigerant jacket.

[0037] 6(a) and 6(b) are schematic cross-sectional views showing the relationship between the deflection of the battery pack and the torsion of the left and right end plates. FIG. 6(a) shows the case of only a normal refrigerant jacket, and FIG. 6(b) shows the case of a reinforcing plate type refrigerant jacket.

[0038] 7(a), 7(b), and 7(c) are graphs showing the relationship between the side frames of the reinforcing plate type refrigerant jacket and the number of the side frames and the deflection amount of the battery pack.

[0039] Figure 8 It is a perspective view schematically showing a refrigerant jacket and a unit assembly.

[0040] Fig. 9 Yes means Figure 1 A perspective view of a method for manufacturing a battery pack shows a state in which a unit stack formed by arranging unit assemblies and bonding bodies of refrigerant jackets is inserted into a battery case, and a busbar module is welded to the unit stack to form a unit body.

[0041] Fig.10 Yes means Figure 1 A perspective view of a method for manufacturing a battery pack shows a formed unit body in which a battery case is placed.

[0042] Fig.11 It is a partially enlarged perspective view of a battery case of a battery pack according to a second embodiment of the present invention.

[0043] Fig.12 is Fig.11 A partially enlarged stereoscopic view of a battery pack having a battery cell and a refrigerant jacket mounted on a battery housing.

[0044] [Explanation of Symbols]

[0045] 1.101: Battery Pack

[0046] 10: Battery housing

[0047] 11: Front end panel

[0048] 12: Rear end plate

[0049] 13: Left end plate

[0050] 13a: Incision

[0051] 14: Right end plate

[0052] 14a: Incision

[0053] 15: Bottom plate

[0054] 16: Divider

[0055] 17: Battery unit storage area

[0056] 18: Buffer component

[0057] 20: Battery Cell

[0058] 20A: Unit joint

[0059] 21: Terminal

[0060] 30: Refrigerant jacket

[0061] 30a: Left end face

[0062] 30b: Right end face

[0063] 30c: Upper part of the end

[0064] 30R: Enhanced plate type refrigerant jacket

[0065] 33: Refrigerant inlet

[0066] 34: Refrigerant passage

[0067] 35: Refrigerant outlet

[0068] 40: Refrigerant circulation piping

[0069] 41: Inlet side socket

[0070] 41a: One side inlet piping

[0071] 41b: Other side inlet piping

[0072] 42: outlet side socket

[0073] 42a: One side outlet piping

[0074] 42b: Other side outlet piping

[0075] 50: Cell stack

[0076] 60: Busbar module

[0077] 61: Positive side terminal

[0078] 62: Negative side terminal

[0079] 70: Unit

[0080] δ: Deflection DETAILED DESCRIPTION

[0081] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0082] [First embodiment]

[0083] This embodiment is a structure in which the upper parts of both ends of the reinforcing plate-type refrigerant jacket are joined to the upper parts of the side end plates of the battery housing. Figure 1 And the enlarged view of its C part Figure 2 As shown, the battery pack 1 of the present embodiment includes a battery case 10 , a plurality of battery cells 20 , a plurality of refrigerant jackets 30 , and a refrigerant flow pipe 40 .

[0084] The battery case 10 is a thin box-shaped case extending in a first direction (front-rear direction AA) and a second direction (left-right direction BB) which are orthogonal to each other and form a horizontal plane, and includes: a front end plate 11 and a rear end plate 12 arranged at both ends in the first direction, a left end plate 13 and a right end plate 14 arranged at both ends in the second direction and composed of extruded materials, a bottom plate 15, and an upper plate (not shown). A partition plate 16 is arranged near the front end plate 11 inside, and a battery unit storage section 17 is formed behind it. In addition, a buffer member 18 that is roughly trapezoidal in plan view is arranged further forward than the front end plate 11, which can absorb external impact when the battery pack 1 is arranged at the bottom of the vehicle body.

[0085] like Figure 4 As shown, the battery cell 20 in this embodiment is a square lithium-ion battery with two terminals 21 protruding from the upper side. The battery cell 20 is composed of a unit assembly 20A in which six cells are arranged in a row and joined in the second direction (left-right direction). In the present invention, the shape of the battery cell 20 is not limited to a square shape, and may be, for example, a cylindrical shape. In the case of a square shape, there is no need to fill the space between the battery cells 20 with resin, and the environmental load during recycling is small. In addition, the type of battery is not limited to a lithium-ion battery, and may be an all-solid-state lithium-ion battery or a sodium-ion battery.

[0086] The refrigerant jacket 30 is a component that is arranged in the battery case 10 in alternating surface contact with the unit assembly 20A in the first direction (front-back direction) and cools each battery cell 20. As shown in FIG. 5(a) and FIG. 5(b), each refrigerant jacket 30 includes an aluminum extruded member having a rectangular shape and a predetermined thickness and having a length and height substantially the same as the unit assembly 20A, and has a refrigerant inlet 33 provided on the left end face 30a, a refrigerant passage 34 provided inside, and a refrigerant outlet 35 provided on the right end face 30b. The refrigerant jacket 30 is not limited to an extruded member, and for example, another plate may be joined to a plate having a groove on the surface, and the groove may be used as a refrigerant flow path.

[0087] like Figure 3 and Figure 8As shown, the refrigerant circulation piping 40 includes: an inlet side socket 41 connected to one end (left end) of the refrigerant jacket 30 in the second direction (left-right direction); and an outlet side socket 42 connected to the other end (right end) of the refrigerant jacket 30. The inlet side socket 41 includes: a one-side inlet piping 41a protruding from one side (front side) to the first direction; and another-side inlet piping 41b protruding from the other side (rear side) to the first direction. On the other hand, the outlet side socket 42 includes: a one-side outlet piping 42a protruding from one side (front side) to the first direction; and another-side outlet piping 42b protruding from the other side (rear side) to the first direction.

[0088] When two refrigerant jackets 30 are adjacent to each other with the unit assembly 20A sandwiched therebetween, the inlet piping 41a on one side of the inlet side socket 41 connected to one of the refrigerant jackets 30 and the outlet piping 42a on one side of the outlet side socket 42 are respectively, for example, embedded and connected to the inlet piping 41b on the other side of the inlet side socket 41 and the outlet piping 42b on the other side of the outlet side socket 42 connected to the other refrigerant jacket 30. Figure 3 This connection structure on the outlet side is represented. In this way, the inlet side sockets 41 of all the refrigerant jackets 30 arranged in the battery case 10 are connected to each other, and the outlet side sockets 42 are connected to each other. In addition, the inlet piping 41a on one side of the front section and the outlet piping 42a on one side of the front section are not provided, and one side is sealed. On the other hand, a refrigerant supply piping (not shown) is connected to the inlet piping 41b on the other side of the last section, and a refrigerant return piping (not shown) is connected to the outlet piping 42a on one side of the last section. When refrigerant (water) is supplied from the refrigerant supply piping (not shown) to a group of refrigerant jackets 30 connected in this way, the water branches and flows in parallel to the refrigerant passages 34 of each refrigerant jacket 30, cools the battery cells 20, and merges to flow to the refrigerant return pipe (not shown).

[0089] Here, at least a part of the refrigerant jacket 30 is set as a reinforcing plate type refrigerant jacket 30R, which is configured such that: the upper part 30c of the two ends in the second direction (left-right direction) is extended in the second direction, and while avoiding the sockets (41, 42) of the refrigerant flow pipe 40, it is connected to the upper part of the left end plate 13 and the right end plate 14 constituting the two ends in the second direction (left-right direction) of the battery case 10, thereby improving the rigidity of the battery case 10. Since the battery pack 1 of the present embodiment is thin and carries a plurality of battery cells 20, when it is horizontally arranged in a state where the left and right ends are supported by the bottom of the car, the central part is easily lowered and bent due to its own weight. In the above case, as shown in FIG. 6(a), the left end plate 13 and the right end plate 14 of the battery case 10, which are respectively composed of extruded materials, are respectively twisted and deformed in such a way that the upper parts approach each other (the double-dashed lines in FIG. 6(a)). Therefore, as shown in FIG6(b), when the upper portions 30c of the two end portions of the enhanced plate-type refrigerant jacket 30R are respectively joined to the upper portions of the left end plate 13 and the right end plate 14, the rigidity of the enhanced plate-type refrigerant jacket 30R is enhanced, and the upper portions of the left end plate 13 and the right end plate 14 are restrained from approaching each other, thereby reducing the deflection amount δ of the battery pack 1 (the double dotted line in FIG6(b)).

[0090] If all the refrigerant jackets 30 are set as reinforced plate type refrigerant jackets 30R, the number of steps for joining the upper parts of the two ends of the reinforced plate type refrigerant jackets 30R to the upper parts of the left end plate 13 and the right end plate 14 during the manufacture of the battery pack 1 increases, and the number of steps for disassembly during recycling also increases. Therefore, in the present embodiment, a sufficient number of reinforced plate type refrigerant jackets 30R required to reduce the deflection amount δ of the battery pack 1 to a predetermined value is adopted. FIG. 7(a), FIG. 7(b), and FIG. 7(c) show the simulation results of the relationship between the side frame (FRM) (8mm aluminum plate) similar to the reinforced plate type refrigerant jacket 30R in the battery pack of the unit-group structure with a first direction of 1800mm×a second direction of 1200mm and a load of 5500N (561kgf) and the number of the side frames and the deflection amount δ of the battery pack. Therefore, if 9 reinforced plate type refrigerant jackets 30R equivalent to the side FRM connected to the upper part are set in the first direction, the deflection amount δ becomes less than 1mm as the target. In other words, if the reinforcing plate type refrigerant jacket 30R is provided every 200 mm in the first direction, the deflection amount δ can be set to 1 mm or less.

[0091] like Fig. 9As shown, two terminals 21 provided on the upper surface of each battery cell 20 are connected to a busbar module 60 of a copper plate punched as a wiring circuit by welding, and are connected in parallel and in series within the wiring circuit, and are finally integrated into a positive terminal 61 and a negative terminal 62. By applying a voltage between the positive terminal 61 and the negative terminal 62 from the outside, each battery cell 20 can be charged, and the power after charging each battery cell 20 can be supplied from the positive terminal 61 and the negative terminal 62 to the vehicle drive motor, etc.

[0092] Next, a method for manufacturing the battery pack 1 of the present embodiment configured as described above will be described.

[0093] First, if Figure 8 As shown, a plurality of battery cells 20 are arranged in a row in the second direction (left-right direction) and joined to form a unit assembly 20A. On the other hand, the refrigerant jacket 30 and the refrigerant jacket 30R are connected to the two ends 30a, 30b of the refrigerant jacket 30 and the refrigerant jacket 30R. The socket 41 and the socket 42 are connected.

[0094] Next, the unit assembly 20A and the refrigerant jacket 30 are alternately arranged and connected to each other in a manner of surface contact with each other in the first direction (front-back direction AA). At this time, one of the plurality of (four in this embodiment) refrigerant jackets 30 is set as a reinforcing plate type refrigerant jacket 30R in which the upper part 30c of both ends is extended in the second direction.

[0095] In addition, at this time, in the two refrigerant jackets 30 of the clamping unit assembly 20A, the inlet piping 41a on one side of the inlet side socket 41 connected to one of the refrigerant jackets 30 and the outlet piping 42a on one side of the outlet side socket 42 are respectively embedded and connected to the inlet piping 41b on the other side of the inlet side socket 41 and the outlet piping 42b on the other side of the outlet side socket 42 connected to the other refrigerant jacket 30.

[0096] Next, if Fig. 9 As shown in FIG. 1 , the cell stack 50 thus formed is inserted into the battery case 10, and then the surface of each battery cell 20 on which the terminal 21 is arranged (at Fig. 9 The busbar module 60 in which the wiring circuit is assembled is placed and welded to each terminal 21 to form a unit body 70.

[0097] The unit cell 70 in which the battery case 10 is placed is shown in FIG. Fig.10 Furthermore, the refrigerant supply pipe (not shown) and the refrigerant return pipe (not shown) are connected, urethane foam is filled in the gap around the unit body 70 as needed, and an upper plate (not shown) is attached, thereby completing the battery pack 1.

[0098] According to this embodiment, the upper portions 30c of the two ends of the reinforced plate-type refrigerant jacket 30R are connected to the upper portions of the left end plate 13 and the right end plate 14 of the battery case 10 while avoiding the sockets (41, 42) of the refrigerant circulation piping 40, thereby improving the rigidity of the battery case 10 and utilizing the socket coupling mechanism of the refrigerant circulation piping 40.

[0099] [Second embodiment]

[0100] In this embodiment, the upper portion 30c of the reinforcing plate type refrigerant jacket 30R at both ends in the second direction is fitted into the notches 13a and 14a provided in the end plates (13, 14) constituting both ends in the second direction (left-right direction BB) of the battery case 10. The same reference numerals are given to the same or substantially the same components as those in the first embodiment, and repeated descriptions are omitted. Fig.11 1 is a perspective view showing the left end plate 13 of the battery case 10 in the battery pack 101 of the present embodiment. Fig.11 As shown, three cutouts 13a are provided at the inner corners of the left end plate 13. Although not shown in the figure, a total of nine cutouts 13a are provided in the left end plate 13, and a total of nine cutouts 14a are provided in the right end plate 14. Fig.12 1 is a partially enlarged perspective view of a battery pack 101 in which a battery unit 20, a refrigerant jacket 30, and a refrigerant jacket 30R are mounted on the battery housing 10, and an upper portion 30c of the left end portion of the reinforcing plate type refrigerant jacket 30R is fitted into each notch 13a (see Fig.11 ). Although not shown in the figure, the upper portion 30c of the left end or right end of the reinforcing plate type refrigerant jacket 30R is also fitted into the other cutout 13a of the left end plate 13 and the cutout 14a of the right end plate 14. The other structures are the same as those of the first embodiment.

[0101] According to the above structure, the joint surface of each notch 13a, 14a and the upper portion 30c of both ends of the reinforcing plate type refrigerant jacket 30R increases, so the joint strength increases, and the rigidity of the battery case 10 is further improved. Furthermore, according to the positions of the notches 13a and 14a, the position of the reinforcing plate type refrigerant jacket 30R in the first direction (front-back direction AA) is partially determined, so the position accuracy of each battery cell 20 is improved, and the position accuracy of the terminal 21 of the battery cell 20 is improved. As a result, the required positioning accuracy of the busbar module 60 relative to the cell stack 50 including each battery cell 20 in the busbar module joining process of the subsequent process can be relaxed, and the miniaturization of the components or the reduction of processing costs can be achieved.

[0102] The embodiments of the present invention have been described above, but the present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the technical ideas described in the claims, the specification, and the drawings. For example, in the embodiments described above, the refrigerant flow pipe 40 is a refrigerant flow pipe 40 connected to an inlet side socket 41 and an outlet side socket 42 of a predetermined structure, but the present invention is not limited to this, and any refrigerant flow pipe 40 may be used as long as it can be connected to the left and right ends 30a and 30b on the refrigerant jacket 30 and the refrigerant jacket 30R.

[0103] In the above-mentioned embodiments, one reinforcing plate type refrigerant jacket 30R is provided for every four refrigerant jackets 30 arranged in the first direction, but one reinforcing plate type refrigerant jacket 30R may be provided for every three, one for every five, or any other number.

Claims

1. A battery pack comprising: The battery housing is extended in a first direction and a second direction which are orthogonal to each other and form a horizontal plane and is box-shaped; a plurality of battery cells arranged in the battery housing; and A plurality of refrigerant jackets have refrigerant passages therein and cool the plurality of battery cells, wherein the battery pack The plurality of battery cells constitute a cell assembly in which a plurality of battery cells are arranged in a row in the second direction and joined together. The unit assembly and the refrigerant jacket are arranged alternately in the first direction in a manner of surface contact with each other. Each of the refrigerant jackets is connected to the refrigerant circulation pipes arranged on both sides of the second direction. At least a part of the refrigerant jackets is a reinforced plate type refrigerant jacket as follows, which is constructed as follows: the upper parts of the two end parts in the second direction are extended in the second direction, while avoiding the refrigerant circulation pipes, and are joined to the upper parts of the end plates of the battery case constituting the two end parts in the second direction, thereby improving the rigidity of the battery case. 2 . The battery pack according to claim 1 , wherein one of the reinforcing plate type refrigerant jackets is provided in every three of the refrigerant jackets arranged in the first direction. 3 . The battery pack according to claim 1 , wherein one of the reinforcing plate type refrigerant jackets is provided in every four of the refrigerant jackets arranged in the first direction. 4 . The battery pack according to claim 1 , wherein one of the reinforcing plate type refrigerant jackets is provided in every five of the refrigerant jackets arranged in the first direction. 5 . The battery pack according to claim 1 , wherein the reinforcing plate type refrigerant jacket is provided every 200 mm±20 mm in the first direction of the battery case. 6 . The battery pack according to claim 1 , wherein upper portions of both ends of the reinforcing plate type refrigerant jacket in the second direction are fitted into cutouts provided at end plates constituting both ends of the battery case in the second direction.

7. The battery pack according to claim 1, wherein the refrigerant circulation pipe comprises: an inlet-side socket connected to one end portion of the refrigerant jacket in the second direction; and an outlet-side socket connected to the other end of the refrigerant jacket in the second direction, The inlet-side socket has: a one-side inlet pipe protruding from one side toward the first direction; and an other-side inlet pipe protruding from the other side toward the first direction. The outlet side socket comprises: a one-side outlet pipe protruding from one side toward the first direction; and an other-side outlet pipe protruding from the other side toward the first direction. And the structure is as follows: when the two refrigerant jackets are adjacent to each other with the unit assembly sandwiched therebetween, the one-side inlet piping of the inlet-side socket connected to one refrigerant jacket and the one-side outlet piping of the outlet-side socket are respectively connected to the other-side inlet piping of the inlet-side socket connected to the other refrigerant jacket and the other-side outlet piping of the outlet-side socket.

8. A method for manufacturing a battery pack, comprising: The battery housing is extended in a first direction and a second direction which are orthogonal to each other and constitute a horizontal plane and is box-shaped; a plurality of battery cells arranged in the battery housing; and A plurality of refrigerant jackets have refrigerant passages therein and cool the plurality of battery cells. The manufacturing method comprises the following steps: Arranging the plurality of battery cells in a row in the second direction and joining them to form a plurality of cell junction bodies; In the battery case, the unit assemblies and the refrigerant jackets are alternately arranged in the first direction in a manner of surface contact with each other; and The upper portions of at least a portion of the refrigerant jacket at both ends in the second direction are joined to upper portions of end plates constituting both ends of the battery case in the second direction, thereby increasing the rigidity of the battery case.

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