Cell holder and battery pack housing

Abstract

To provide a cell holder that can improve the vibration resistance and earthquake resistance of a cell assembly stack housed in the battery pack housing, and a battery pack housing.SOLUTION: Convex portions 63a are formed to protrude from both side surfaces of the cell holders that constitute both side surfaces of a cell assembly stack. These convex portions 63a formed on both side surfaces of the cell holders, which are formed to protrude from the side surfaces of some of the cell holders that constitute at least a part of the left side surface of the cell assembly stack and from the side surfaces of some of the cell holders that constitute at least a part of the right side surface of the cell assembly stack, are locked in a Z-axis direction by locking members 51 fixed to the inner surfaces of both side plates of a left side plate 7 and a right side plate 9 of the housing, thereby preventing movement in the Z-axis direction.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a cell holder that holds a laminate cell in a cell assembly, and a battery pack housing that houses a cell assembly stack formed by stacking cell assemblies. [Background technology]

[0002] Lithium ion secondary batteries (LIBs, hereinafter referred to as LIBs) used in power storage devices and the like are known for their high energy density, small size, and light weight compared to other secondary batteries such as nickel-cadmium batteries and nickel-metal hydride batteries.

[0003] The LIB is, for example, enclosed in a laminate film to form a laminate cell, which is then held in a cell holder to form a cell assembly. The cell assembly further comprises laminate cells connected in series to form a LIB module, which is a cell assembly stack. The LIB module is connected to a control circuit including a module monitoring unit (MMU: Module Management Unit) that monitors the voltage and temperature of each LIB, and is housed inside the housing of the battery pack.

[0004] For example, Patent Documents 1 and 2 disclose lithium secondary battery unit sets in which a large number of such LIBs are stacked, and in which LIBs are housed more firmly and stably. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5465726 [Patent Document 2] Patent No. 5249339 Summary of the Invention [Problem to be solved by the invention]

[0006] The above-mentioned battery pack is mounted on various loads to which power is to be supplied, such as an uninterruptible power supply, an industrial robot, an electric vehicle, an unmanned aerial vehicle, etc. In this case, it is necessary to deal with vibrations that the cell assembly stack receives from the load and vibrations caused by earthquakes, and it is preferable to take measures against vibrations.

[0007] In view of the above, an object of the present invention is to improve the vibration resistance and earthquake resistance of a cell assembly stack housed in a housing of a battery pack mounted on a load. [Means for solving the problem]

[0008] To this end, the present invention comprises: A cell holder for holding a laminate cell in a cell assembly constituting a cell assembly stack housed in a battery pack housing, comprising: a first frame that holds the laminate cell from one side of the laminate cell; a second frame that holds the laminate cell from the other side of the laminate cell; a fixing means for fixing the first frame and the second frame to maintain a cell assembly state in which the laminate cell is sandwiched between the first frame and the second frame; The cell assembly stack is formed by stacking cell assemblies in one direction to be integrally formed, and is formed so as to protrude or recess on both side surfaces of the cell holder constituting both side surfaces, and is formed so as to protrude or recess on the side surface of the cell holder constituting at least a part of one side surface of the cell assembly stack and on the side surface of the cell holder constituting at least a part of the other side surface of the cell assembly stack. The protrusions or recesses are engaged in a direction perpendicular to the one direction by engaging members fixed to the inner surfaces of both side plates of the housing that sandwich both side surfaces of the cell assembly stack, thereby preventing movement in a direction perpendicular to the one direction. A cell holder was constructed comprising:

[0009] According to this configuration, protrusions or recesses are formed on both side surfaces of the cell holders constituting both side surfaces of the cell assembly stack formed integrally by stacking the cell assemblies in one direction. These protrusions or recesses formed on both side surfaces of the cell holders protruding or recessed from the side surfaces of some of the cell holders constituting at least a part of one side surface of the cell assembly stack and from the side surfaces of some of the cell holders constituting at least a part of the other side surface of the cell assembly stack are engaged in a direction perpendicular to the one direction by engaging members fixed to the inner surfaces of both side plates of the housing, thereby preventing movement in a direction perpendicular to the one direction.

[0010] Since the cell assembly stack is formed by integrally forming a plurality of cell assemblies, the protrusions or recesses formed on the respective sides of at least some of the cell holders constituting the cell assembly stack are engaged in a direction perpendicular to the one direction by the engaging members fixed to the inner surfaces of both side plates of the battery pack housing, thereby preventing the movement of the cell assembly stack within the housing in a direction perpendicular to the one direction, which is the stacking direction, thereby improving the vibration resistance and earthquake resistance of the cell assembly stack within the battery pack housing in a direction perpendicular to the stacking direction.

[0011] Furthermore, the movement of the cell assembly stack in the battery pack housing in a direction perpendicular to the stacking direction is prevented by engaging the protrusions or recesses of the cell holder with the locking members of the housing when the cell assembly stack is housed in the battery pack housing. Therefore, the vibration resistance and earthquake resistance of the cell assembly stack in the direction perpendicular to the stacking direction in the battery pack housing can be improved by simply assembling the battery pack without performing any special process when assembling the battery pack, and without reducing the assembly efficiency of the battery pack.

[0012] In addition, when recesses are formed on both side surfaces of the cell holder, there are no protruding parts on the outer periphery of the cell assembly, so the housing of the battery pack that houses the cell assembly stack can be made compact, thereby improving the energy density per unit volume of the battery pack.

[0013] The present invention is also characterized in that the convex portion or concave portion is formed in at least one of the first frame and the second frame constituting the side surface of the cell assembly stack, so as to protrude from or be recessed in the side surface.

[0014] According to this configuration, the convex or concave portion is formed by at least one of the first frame and the second frame that constitute the cell assembly, so that the vibration resistance and earthquake resistance of the cell assembly stack in a direction perpendicular to its stacking direction within the battery pack housing can be improved without increasing the number of parts that constitute the cell assembly.

[0015] In addition, the present invention is characterized in that the protrusion is formed by a part of the fixing means.

[0016] According to this configuration, the convex portion is realized by part of the fixing means, so that the components of the cell assembly can be reduced, and the vibration resistance and earthquake resistance of the cell assembly stack in a direction perpendicular to its stacking direction within the battery pack housing can be improved at low cost.

[0017] The present invention also provides a method for producing a semiconductor device comprising the steps of: the fixing means is constituted by a joining member that clamps and fixes the first frame and the second frame at side surfaces of the first frame and the second frame that constitute the side surfaces of the cell assembly stack, The protrusions are formed by portions of the connecting member that protrude from the side surfaces of the first frame and the second frame.

[0018] According to this configuration, the fixing means and the convex portion are formed by a connecting member that clamps and fixes the first frame and the second frame on the side surfaces of the first frame and the second frame, thereby reducing the number of parts that make up the convex portion and the assembly labor required.

[0019] The present invention is also characterized in that the fixing means is composed of a connecting member that clamps and fixes the first frame and the second frame within a recess formed by recessing the side surfaces of the first frame and the second frame that constitute the side surfaces of the cell assembly stack, leaving a recess portion of the recess that engages with the locking portion.

[0020] According to this configuration, since the fixing means is provided within the recess of the recess and does not protrude from the outer periphery of the cell assembly, the size of the cell assembly stack can be reduced, and therefore the housing of the battery pack that houses the cell assembly stack can be made compact, thereby improving the energy density per unit volume of the battery pack.

[0021] The present invention further provides a cell holder for holding a laminate cell in a cell assembly constituting a cell assembly stack housed in a battery pack housing, the cell holder comprising: a first frame that holds the laminate cell from one side of the laminate cell; a second frame that holds the laminate cell from the other side of the laminate cell; a fixing means for fixing the first frame and the second frame to maintain a cell assembly state in which the laminate cell is sandwiched between the first frame and the second frame; A cell assembly laminate in which cell assemblies are stacked in one direction to be integrated has a convex portion formed by protruding from one of both side surfaces of a cell holder constituting both side surfaces, and a concave portion formed by recessing into the other of both side surfaces, the convex portion formed by protruding from one side surface of the cell holder constituting at least a part of one side surface of the cell assembly laminate, and the concave portion formed by recessing from the other side surface of the cell holder constituting at least a part of the other side surface of the cell assembly laminate are engaged in a direction perpendicular to the one direction by engaging members fixed to the inner surfaces of both side plates of a housing that sandwich both side surfaces of the cell assembly laminate, and thus the convex portion and the concave portion are prevented from moving in a direction perpendicular to the one direction. A cell holder was constructed comprising:

[0022] According to this configuration, since the cell assembly stack is formed by integrally forming a plurality of cell assemblies, the protrusions formed on one side and the recesses formed on the other side of at least some of the cell holders constituting the cell assembly stack are respectively engaged in a direction perpendicular to the one direction by the engaging members fixed to the inner surfaces of both side plates of the battery pack housing, thereby preventing the movement of the cell assembly stack within the housing in a direction perpendicular to the one direction, which is the stacking direction, thereby improving the vibration resistance and earthquake resistance of the cell assembly stack within the battery pack housing in a direction perpendicular to the stacking direction.

[0023] In addition, the present invention provides a housing for a battery pack that houses a cell assembly stack in which a locking member that prevents movement in a direction perpendicular to one direction of a convex or concave portion is fixed to the inner surface of both side plates that sandwich both side surfaces of the cell assembly stack, and in which any of the cell holders described above are stacked.

[0024] According to this configuration, it is possible to provide a battery pack housing that can improve the vibration resistance and earthquake resistance of the cell assembly stack in a direction perpendicular to the stacking direction within the battery pack housing. Effect of the Invention

[0025] According to the present invention, it is possible to provide a cell holder and a battery pack housing that can improve the vibration resistance and earthquake resistance of a cell assembly stack in a direction perpendicular to the stacking direction within the battery pack housing. [Brief description of the drawings]

[0026] [Figure 1] 1 is an external perspective view showing a housing of a battery pack according to an embodiment of the present invention; [Diagram 2] 1 is a partially disassembled external perspective view of a battery pack housing that houses a cell assembly stack constituted by a cell holder according to a first embodiment of the present invention; FIG. [Diagram 3] FIG. 2 is a side view of a housing of the battery pack according to the embodiment. [Figure 4] 6 is a cross-sectional view of the housing of the battery pack shown in FIG. 3 taken along line VI-VI. [Diagram 5] 4(a) is a cross-sectional side view of the casing of the battery pack shown in FIG. 3 taken along line VV, (b) is a detailed view of area A shown in (a), and (c) is a diagram showing a modified example of area A shown in (a). [Figure 6] FIG. 2 is a perspective view illustrating a cell assembly including a cell holder according to the first embodiment. [Figure 7] FIG. 7(a) is a front view of the cell assembly illustrated in FIG. 6, and FIG. [Figure 8] 7 is an exploded perspective view of the cell assembly illustrated in FIG. 6 when disassembled in the Y-axis direction. [Figure 9] 7 is an exploded side view of the cell assembly illustrated in FIG. 6 when disassembled in the Y-axis direction. [Figure 10] FIG. 11 is a perspective view illustrating a cell assembly including a cell holder according to a second embodiment of the present invention. [Figure 11] 10. (a) is a cross-sectional side view taken along line VV of the housing of the battery pack shown in FIG. 3 which houses a cell assembly stack composed of the cell assembly shown in FIG. 10. (b) is a detailed view of region B shown in (a). (c) is a diagram showing a modified example of region B shown in (a). [Figure 12] FIG. 13 is a perspective view illustrating a cell assembly including a cell holder according to a modified example of the first embodiment. [Figure 13] FIG. 13(a) is a front view of the cell assembly illustrated in FIG. 12, and FIG. 13(b) is a side view thereof. [Figure 14] 13A is a perspective view showing a state in which a connecting member has been removed from the cell assembly illustrated in FIG. 12, and FIG. 13B is a perspective view of the removed connecting member alone. [Figure 15] FIG. 14(a) is a front view of the cell assembly in the state shown in FIG. 14(a), and FIG. [Figure 16] FIG. 11 is a perspective view illustrating a cell assembly including a cell holder according to a modified example of the second embodiment. [Figure 17] FIG. 17(a) is a front view of the cell assembly illustrated in FIG. 16, and FIG. 17(b) is a side view thereof. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, a cell holder and a battery pack housing according to an embodiment of the present invention will be described in detail with reference to the attached drawings. Note that the same or corresponding parts in each drawing will be described with the same reference numerals. Also, the XYZ coordinate axes in Fig. 1 are the same as the XYZ coordinate axes in Fig. 2 and the subsequent drawings.

[0028] Fig. 1 is an external perspective view of the housing of a battery pack 1 according to an embodiment of the present invention, and Fig. 2 is an external perspective view of the housing of the battery pack 1 according to the embodiment when the housing is partially disassembled. The housing of the battery pack 1 according to the embodiment contains a cell assembly stack 15 constituted by a cell holder 62 according to a first embodiment of the present invention, which will be described later.

[0029] 1 and 2, the housing of the battery pack 1 is composed of a top plate 3, a bottom plate 5, a left side plate 7, a right side plate 9, a front plate 11, and a rear plate 13. Fig. 2 is an external perspective view of the housing of the battery pack 1 shown in Fig. 1 with the top plate 3 and the right side plate 9 removed. In this embodiment, the housing is formed of a zinc-plated steel plate that has been surface-painted, and the bottom plate 5, the left side plate 7, the front plate 11, and the rear plate 13 are formed by bending a single zinc-plated steel plate.

[0030] The bottom plate 5 is disposed on the XY plane, the left side plate 7 is disposed on the YZ plane, and the front plate 11 and the rear plate 13 are disposed on the XZ plane. The side of the bottom plate 5 in the negative Y-axis direction and the side of the front plate 11 in the negative Z-axis direction, and the side of the bottom plate 5 in the positive Y-axis direction and the side of the rear plate 13 in the negative Z-axis direction are each connected by welding.

[0031] 2, the upper end of the front panel 11 in the positive direction of the Z axis is bent in the positive direction of the Y axis to provide a tabletop connection margin. Screw holes 20 are drilled in two places on this tabletop connection margin, and screw holes 19 are drilled in two places on the front end of the tabletop 3 in the negative direction of the Y axis, which is placed on the XY plane. The front end of the tabletop 3 in the negative direction of the Y axis is fastened to the tabletop connection margin of the front panel 11 by screws passing through the screw holes 19 and 20, respectively.

[0032] Further, the right end portion in the X-axis positive direction of the front plate 11 is bent in the Y-axis positive direction to provide a side plate connection margin. Screw holes 26 are drilled in two places on this side plate connection margin, and screw holes 25 are drilled in two places on the front end portion in the Y-axis negative direction of the right side plate 9 arranged on the YZ plane. The front end portion in the Y-axis negative direction of the right side plate 9 is fastened to the side plate connection margin of the front plate 11 by screws passing through the screw holes 25 and 26, respectively.

[0033] Similarly, the upper end of rear plate 13 in the positive direction of the Z axis is bent in the negative direction of the Y axis to provide a top plate connection margin. Screw holes 18 are drilled in two places on this top plate connection margin, and screw holes 17 are drilled in two places on the rear end of top plate 3, which is placed on the XY plane, in the positive direction of the Y axis. The rear end of top plate 3 in the positive direction of the Y axis is fastened to the top plate connection margin of rear plate 13 by screws passing through screw holes 17 and 18, respectively.

[0034] Further, the right end portion in the X-axis positive direction of rear plate 13 is bent in the Y-axis negative direction to provide a side plate connection margin. Screw holes 22 are drilled in two places on this side plate connection margin, and screw holes 21 are drilled in two places on the rear end portion in the Y-axis positive direction of right side plate 9 arranged on the YZ plane. The rear end portion in the Y-axis positive direction of right side plate 9 is fastened to the side plate connection margin of rear plate 13 by screws passing through screw holes 21 and 22, respectively.

[0035] Furthermore, the upper end of the left side plate 7 in the positive direction of the Z axis is bent in the positive direction of the X axis to provide a tabletop connection margin. Screw holes 16 are drilled in four places on this tabletop connection margin, and screw holes 14 are drilled in four places on the left end of the tabletop 3 placed on the XY plane in the negative direction of the X axis. The left end of the tabletop 3 in the negative direction of the X axis is fastened to the tabletop connection margin of the left side plate 7 by screws passing through screw holes 14 and 16, respectively.

[0036] Furthermore, the right end portion in the X-axis positive direction of the tabletop 3 is bent in the Z-axis negative direction to provide a side panel connection margin (not shown). Screw holes (not shown) are provided at four locations on this side panel connection margin, and screw holes 23 are provided at four locations on the upper end portion in the Z-axis positive direction of the right side panel 9 arranged on the YZ plane. The upper end portion in the Z-axis positive direction of the right side panel 9 is fastened to the side panel connection margin of the tabletop 3 by screws passing through the screw holes (not shown) and the screw holes 23 in the side panel connection margin of the tabletop 3.

[0037] A pair of external output terminals 27, a pair of communication connectors 29, and one handle 31 are provided on the outer surface of the front of the front plate 11. The cell assembly stack 15, which is a LIB module, is connected to an MMU (Module Monitoring Unit: Module Management Unit) board 33 provided on the inner surface of the rear of the front plate 11 and is housed inside the housing of the battery pack 1. A control circuit including an MMU that monitors the voltage and temperature of each LIB is formed on the MMU board 33. The communication connector 29 is electrically connected to this MMU board 33. Power output from each LIB of the cell assembly stack 15 is taken out from each external output terminal 27. A force is applied to the handle 31 when the battery pack 1 is moved, and when a force in the negative Y-axis direction is applied, for example, the battery pack 1 is moved horizontally.

[0038] The cell assembly stack 15 housed inside the housing of the battery pack 1 is configured by stacking a plurality of cell assemblies 41 (see FIG. 6) in one direction in the Y-axis direction. As shown in FIG. 6, the cell assembly 41 holds one laminate cell 61 between a first frame 63 and a second frame 64 that constitute a cell holder 62 in the cell assembly 41. The first frame 63 holds the laminate cell 61 from one side of the laminate cell 61, and the second frame 64b holds the laminate cell 61 from the other side of the laminate cell 61.

[0039] Each cell holder 62 has protrusions 63a, 64a formed thereon, protruding from both side surfaces of the cell holder 62 that constitute both side surfaces of the cell assembly stack 15. In this embodiment, the protrusions 63a, 64a are formed by protruding from the side surfaces of both the first frame 63 and the second frame 64 that constitute the side surfaces of the cell assembly stack 15. These protrusions 63a, 64a protrude from each of the both side surfaces of the cell assembly stack 15 in a direction perpendicular to each of the both side surfaces and toward the outside.

[0040] Moreover, in this embodiment, the convex portions 63a, 64a are provided at the lower portions of both side surfaces of the cell assembly stack 15 at positions that contact the bottom plate 5. Moreover, in this embodiment, the convex portions 63a, 64a are, for example, rectangular when viewed from the XZ plane, and the bottom surface that contacts the bottom plate 5 and the top surfaces 63a1, 64a1 that face the bottom surface are substantially parallel to the surface of the bottom plate 5. Moreover, the shapes and dimensions of the convex portions 63a, 64a in the XZ plane are the same.

[0041] Each cell holder 62 constituting the cell assembly stack 15 is collectively fastened by a long bolt 45 and a nut 46 passing through four through holes 62a provided at the four corners of the cell holder 62. As a result, the cell assembly stack 15 is formed by stacking the cell assemblies 41 together in a regular manner and without loosening in the Y-axis direction. In addition, the protrusions 63a, 64a provided on each cell holder 62 are stacked together in a regular manner and without loosening in the Y-axis direction to form a protrusion group 65, and the top surfaces 63a1, 64a1 of the protrusion group 65 facing the bottom surface in contact with the bottom plate 5 are flush with each other.

[0042] The cell assembly stack 15 constitutes a secondary battery module in which the cell assemblies 41 are connected in series by connecting the positive and negative electrodes of two adjacent cell assemblies 41 in parallel, and electrically connecting them in series by a bus bar 35. In this embodiment, the cell assembly stack 15 constitutes a secondary battery module in which 15 pairs of two cell assemblies 41 connected in parallel are connected in series.

[0043] The positive electrode 61a (see FIG. 2) of the laminate cell 61 located at one end of the cell assembly stack 15 is connected to a secondary protection fuse (not shown) called a Self Control Protection (SCP) via a cable (not shown) guided along the left side plate 7 of the housing of the battery pack 1 by fastening members 37, 39, and is connected from the SCP to one external output terminal 27. The negative electrode 61b of the laminate cell 61 located at the other end of the cell assembly stack 15 is connected to the other external output terminal 27 via another cable (not shown).

[0044] A current monitor cable (not shown) connected to the SCP is connected to the MMU board 33, and the current flowing between the positive electrode 61a and the negative electrode 61b is sent to the control circuit of the MMU board 33. In addition, a voltage monitor cable (not shown) connected to each bus bar 35 is connected to the MMU board 33, and the voltage between the terminals of the laminate cell 61 (see FIG. 6) held in each cell assembly 41 is sent to the control circuit of the MMU board 33.

[0045] Furthermore, a thermistor is in contact with a laminate cell 61 held in a specific cell assembly 41 among the cell assemblies 41 constituting the cell assembly stack 15. The thermistor is connected to the MMU board 33 via a temperature monitor cable (not shown). As a result, the temperature of the laminate cell 61 held in the specific cell assembly 41 is measured by the thermistor and sent to the control circuit of the MMU board 33.

[0046] Fig. 3 is a side view of the battery pack 1 shown in Fig. 1, Fig. 4 is a cross-sectional view taken along line VI-VI of the battery pack 1 shown in Fig. 3, and Fig. 5(a) is a cross-sectional view taken along line VV of the battery pack 1 shown in Fig. 3. Fig. 5(b) is a detailed view of region A in Fig. 5(a), and Fig. 5(c) is a view showing a modified example of region A, which will be described later.

[0047] 2 and 4, among the cell assemblies 41 constituting the cell assembly stack 15, the cell assembly 41 closest to the rear plate 13 abuts against one end of each spacer 55. The spacers 55 are bent into an L-shape, and the other end of each spacer 55 is welded to the rear plate 13. The tip of each long bolt 45 protrudes from one end of the corresponding spacer 55, and the protruding portion is screwed into a nut 46 to tighten the cell assembly stack 15 in the Y-axis direction.

[0048] Of the cell assemblies 41 constituting the cell assembly stack 15, the cell assembly 41 closest to the front plate 11 abuts against a fixing member 56 having an L-shaped cross section. Therefore, the cell assembly stack 15 is fixed by the spacer 55 and the fixing member 56 in the Y-axis direction, which is the longitudinal direction of the housing of the battery pack 1.

[0049] Furthermore, among the group of protrusions 65 of the cell assembly stack 15, the upper surfaces of the group of protrusions 65 arranged on the side of the right side plate 9 abut against the locking member 51 having an L-shaped cross section which is fixed integrally to the right side plate 9, and are covered by the locking member 51. In this embodiment, the upper surfaces of the group of protrusions 65 arranged on the side of the right side plate 9 abut against the locking members 51 at two locations on both ends of the cell assembly stack 15 in the longitudinal direction.

[0050] As shown in Fig. 5(b), in this embodiment, the vertical plate 51a of the locking member 51 extending in the Z-axis direction is fixed to the right side plate 9 by welding. A spacer 51c made of an elastic member is attached to the tip of the horizontal plate 51b of the locking member 51 extending in the X-axis direction and perpendicular to the vertical plate 51a. The spacer 51c abuts substantially parallel to the upper surface of the protrusion group 65. In this embodiment, the vertical plate 51a and the horizontal plate 51b constituting the locking member 51 are formed of a zinc-plated steel plate, similar to the housing of the battery pack 1.

[0051] Similarly, of the group of protrusions 65 of the cell assembly stack 15, the upper surface of the group of protrusions 65 arranged on the left side plate 7 abuts against the locking member 51 fixed integrally with the left side plate 7 and is covered by the locking member 51. In this embodiment, the upper surface of the group of protrusions 65 arranged on the left side plate 7 abuts against the locking member 51 at three locations, namely, both ends and the center in the longitudinal direction of the cell assembly stack 15. Of this locking member 51, the vertical plate 51a extending in the Z-axis direction is fixed to the left side plate 7 by welding, and the spacer 59 attached to the horizontal plate 51b abuts against the upper surface of the group of protrusions 65 substantially parallel to it.

[0052] The convex portions 63a, 64a are formed protruding from the side surface of the cell holder 62 constituting at least a part of one side surface of the cell assembly stack 15, and from the side surface of the cell holder 62 constituting at least a part of the other side surface of the cell assembly stack 15, and are engaged in the Z-axis direction perpendicular to the one direction, which is the Y-axis direction, by a locking member 51 fixed to the inner surfaces of both side plates of the left side plate 7 and right side plate 9 of the housing that sandwich both side surfaces of the cell assembly stack 15, thereby preventing movement in the Z-axis direction perpendicular to the one direction.

[0053] In this embodiment, movement in the Z-axis direction is inhibited for the side of the cell holder 62 that abuts against the locking member 51 fixed to the left side plate 7 at three points and constitutes at least a part of the left side of the cell assembly stack 15, and for the protrusions 63a, 64a formed on the side of the cell holder 62 that abuts against the locking member 51 fixed to the right side plate 9 at two points and constitutes at least a part of the right side of the cell assembly stack 15.

[0054] In the present embodiment, spacer 51c provided on the contact surface between convex portions 63a, 64a and horizontal plate 51b of locking member 51 is not an essential component of the present invention. However, spacer 51c not only fills the gap between convex portions 63a, 64a and horizontal plate 51b of locking member 51, but also absorbs the impact that locking member 51 receives from bottom plate 5 when the housing of battery pack 1 vibrates or vibrates.

[0055] Fig. 6 is a perspective view illustrating the cell assembly 41 showing a state in which the cell holder 62 according to the first embodiment holds a laminate cell 61. Fig. 7(a) is a front view of the cell assembly 41 illustrated in Fig. 6 as viewed from the XZ plane, and Fig. 7(b) is a side view of the cell assembly 41 illustrated in Fig. 6 as viewed from the YZ plane. Fig. 8 is an exploded perspective view of the cell assembly 41 illustrated in Fig. 6 when disassembled in the Y-axis direction, and Fig. 9 is an exploded side view of the cell assembly 41 illustrated in Fig. 6 when disassembled in the Y-axis direction.

[0056] In this embodiment, the laminate cell 61 is, for example, a LIB (lithium ion secondary battery) enclosed in an exterior body that is a laminate film. In detail, the laminate cell 61 is configured by housing an electrode laminate together with an electrolyte in a laminate film in which a very thin metal, for example, aluminum or stainless steel, is sandwiched between resin films. The electrode laminate is configured by laminating a positive electrode having a positive electrode layer made of an olivine type positive electrode active material, for example, LiFePO4, on a positive electrode current collector, for example, aluminum foil, and a negative electrode having a negative electrode layer made of a carbon material, for example, graphite, on a negative electrode current collector, for example, copper foil, with a separator interposed therebetween.

[0057] As shown in Fig. 8, among the electrode laminated bodies housed in the laminated cell 61, the positive electrode current collectors are welded together with the positive electrode 61a, and the positive electrode 61a protrudes from the laminated cell 61 in the positive direction of the Z axis. The negative electrode current collectors are welded together with the negative electrode 61b, and the negative electrode 61b protrudes from the laminated cell 61 in the positive direction of the Z axis. The positive electrode 61a is welded to a metal fitting 67, and the negative electrode 61b is welded to a metal fitting 67 disposed in the opposite direction in the X axis direction. Each metal fitting 67 is connected to the bus bar 35 as shown in Fig. 2 by a bolt passed through a screw hole 67c provided at the end of each metal fitting 67.

[0058] In this embodiment, two cell assemblies 41 adjacent to each other in the Y-axis direction of the cell assembly stack 15 are connected in parallel, and therefore the positive electrode 61a of one adjacent cell assembly 41, together with the positive electrode 61a of the other cell assembly 41, is welded to a metal fitting 67 whose screw hole 67c is closer to the negative side of the X-axis. Also, the negative electrode 61b of one adjacent cell assembly 41, together with the negative electrode 61b of the other cell assembly 41, is welded to a metal fitting 67 that is arranged in the opposite direction and whose screw hole 67c is closer to the positive side of the X-axis. For this reason, the screw holes 67c of each metal fitting 67 are arranged away from each other.

[0059] In addition, in a pair of cell assemblies 41 adjacent to each other in the Y-axis direction of the cell assembly stack 15 among the two pairs of cell assemblies 41 connected in parallel, the arrangement of electrodes is reversed to the arrangement shown in Fig. 8. In other words, when viewed in the Y-axis direction, the positive electrode 61a of the pair of adjacent cell assemblies 41 faces the negative electrode 61b shown in Fig. 8, and the negative electrode 61b of the pair of adjacent cell assemblies 41 faces the positive electrode 61a shown in Fig. 8.

[0060] In the pair of cell assemblies 41 adjacent to each other in the Y-axis direction of the cell assembly stack 15 among the two pairs of cell assemblies 41 connected in parallel, the arrangement of the metal fittings 67 is reversed to that shown in Fig. 8. That is, in the adjacent pair of cell assemblies 41, the positive electrode 61a of the adjacent pair of cell assemblies 41 faces the negative electrode 61b shown in Fig. 8, and is connected to a metal fitting 67 whose screw hole 67c is closer to the negative side of the X-axis. In addition, the negative electrode 61b of the adjacent pair of cell assemblies 41 faces the positive electrode 61a shown in Fig. 8, and is connected to a metal fitting 67 whose screw hole 67c is closer to the positive side of the X-axis.

[0061] Therefore, in the pair of adjacent cell assemblies 41, the arrangement of the screw holes 67c in each metal fitting 67 connected to the positive electrode 61a and the negative electrode 61b is different from the arrangement shown in FIG. 8 and is arranged close to each other (see FIG. 2).

[0062] Each metal fitting 67 has a through hole 67a and a notch 67b at both ends in the X-axis direction. When viewed from the XZ plane along the Y-axis positive direction, each through hole 67a and each notch 67b is located between through holes 63c provided at four locations on the first frame 63 and protrusions 64c provided at four locations on the second frame 64.

[0063] Each through hole 63c is provided in an upper frame of the first frame 63 extending in the X-axis direction in the XZ plane. In this embodiment, each through hole 63c is formed in a cylindrical shape, and one is provided at the left end of the upper frame, two at the center, and one at the right end. Each protrusion 64c is provided in an upper frame of the second frame 64 extending in the X-axis direction in the XZ plane. In this embodiment, each protrusion 64c is formed in a cylindrical shape, and one is provided at the left end of the upper frame, two at the center, and one at the right end, corresponding to each of the four through holes 63c provided in the first frame 63.

[0064] In this embodiment, the first frame 63, which abuts against one surface of the laminate cell 61, which is the front surface on the negative side of the Y axis, and the second frame 64, which abuts against the other surface of the laminate cell 61, which is the back surface on the positive side of the Y axis, are each molded from the same resin.

[0065] The first frame 63 includes a through-hole region 63d that is penetrated to accommodate a convex region 61c of the laminate cell 61 in which the electrode stack is housed in the exterior body on the surface of the laminate cell 61. The through-hole region 63d is defined by four inner slopes 63d1, 63d2, 63d3, and 63d4 that surround the through-hole region 63d. The convex region 61c in which the electrode stack is housed in the exterior body is defined by four slopes 61c1, 61c2, 61c3, and 61c4 that surround the convex region 61c with the top surface of the convex region 61c having a smaller area than the bottom surface.

[0066] The second frame 64 includes a recessed region 64d having a recess for accommodating a protruding region (not shown) in which the electrode stack is accommodated in the exterior body on the back surface of the laminate cell 61. The recessed region 64d is defined by four inclined surfaces 64d1, 64d2, 64d3, and 64d4 that surround the recessed region 64d by making the opening area of ​​the recessed region 64d larger than the area of ​​its bottom. The protruding region in which the electrode stack is accommodated in the exterior body on the back surface of the laminate cell 61 is defined by four inclined surfaces (not shown) that are formed in the same manner as the front surface side of the laminate cell 61.

[0067] The first frame 63 is provided with two levers 63e protruding in the Y-axis positive direction on each of the right and left frames extending in the Z-axis direction on the XZ plane. In this embodiment, the two levers 63e provided on the upper and lower parts of the right frame have claws formed at their tips that protrude in the X-axis negative direction. The two levers 63e provided on the upper and lower parts of the left frame (neither shown) have claws formed at their tips that protrude in the X-axis positive direction.

[0068] The second frame 64 is provided with two recesses 64e on each of the right and left frames extending in the Z-axis direction on the XZ plane. Each recess 64e is provided on the upper and lower sides of the right frame and on the upper and lower sides (not shown) of the left frame in correspondence with each of the four levers 63e provided on the first frame 63. In this embodiment, each recess 64e is formed with two depths from both side surfaces on the YZ plane of the second frame 64 (see FIG. 9). The depth on the first frame 63 side of the two depths is shallow, which corresponds to the thickness of the lever 63e in the X-axis direction, and the depth on the side farther from the first frame 63 is deep, which corresponds to the thickness of the lever 63e in the X-axis direction including the claw at the tip of the lever 63e.

[0069] The claws at the tips of the levers 63e snap-fit ​​into the deep notches of the recesses 64e, and the levers 63e are fixed to the recesses 64e, thereby fixing the first frame 63 and the second frame 64. The levers 63e and the recesses 64e constitute fixing means for fixing the first frame 63 and the second frame 64 together, and for maintaining the state of the cell assembly 41A in which the laminate cell 61 is sandwiched between the first frame 63 and the second frame 64.

[0070] The first frame 63 is provided with two protrusions 63f protruding in the negative Y-axis direction on the left frame extending in the Z-axis direction on the XZ plane. In this embodiment, the two protrusions 63f are formed in a cylindrical shape, and one is provided above the left frame and one is provided below the left frame. The second frame 64 is provided with two through holes 64f on the left frame extending in the Z-axis direction. In this embodiment, the two through holes 64f are formed in a cylindrical shape, and when viewed in the XZ plane, one is provided above the left frame and one is provided below the left frame (not shown) in correspondence with the two protrusions 63f provided on the first frame 63.

[0071] When the opposing surfaces of the first frame 63 and the second frame 64 are aligned, the four cylindrical through holes 63c provided in the first frame 63 and the four columnar protrusions 64c provided in the second frame 64 are fitted together via the through holes 67a and the notches 67b provided in the metal fittings 67. At the same time, the four levers 63e provided in the first frame 63 and the four recesses 64e provided in the second frame 64 are fitted together by snap fit. By fitting the first frame 63 and the second frame 64 together, the thermally welded regions 61d located around the protruding regions 61c in which the electrode laminate is housed in the exterior body on each of the front and back surfaces of the laminate cell 61 are sandwiched between the first frame 63 and the second frame 64, and the laminate cell 61 is held by the cell holder 62 and maintained in this held state.

[0072] In this state, of the inclined surfaces 61c1, 61c2, 61c3, and 61c4 that define the convex region 61c on the surface of the laminate cell 61 where the electrode stack is contained in the outer casing, three regions, namely, the heat-sealed region 61d located in the negative direction of the Z axis from the inclined surface 61c1, the heat-sealed region 61d located in the positive direction of the X axis from the inclined surface 61c2, and the heat-sealed region 61d located in the negative direction of the X axis from the inclined surface 61c4, are sandwiched between the first frame 63 and the second frame 64.

[0073] In addition, a convex region 61c on the front surface of the laminate cell 61 where the electrode stack is housed in the outer casing is fixed inside the through region 63d of the first frame 63, and a convex region (not shown) on the back surface of the laminate cell 61 where the electrode stack is housed in the outer casing is fixed inside the recessed region 64d of the second frame 64.

[0074] 7(a), it can be seen that the convex region 61c on the front surface of the laminate cell 61, where the electrode laminate is housed in the exterior body, is fixed inside the through-hole region 63d of the first frame 63. Also, with reference to Fig. 7(b), it can be seen that the thickness of the convex region 61c on the front and back surfaces of the laminate cell 61, where the electrode laminate is housed in the exterior body, is thinner than the thickness that can be accommodated by the through-hole region 63d of the first frame 63 and the recessed region 64d of the second frame 64.

[0075] 6, the surface on the Y-axis negative side of first frame 63 is flush with the surface of convex region 61c where the electrode stack is housed in the exterior body on the surface of laminate cell 61. For example, an aluminum plate that abuts against left side plate 7 may be abutted against these surfaces to achieve a heat dissipation effect for each cell assembly 41.

[0076] Furthermore, by fitting the first frame 63 and the second frame 64 together as described above, the screw holes 63g provided in the four corners of the first frame 63 and the screw holes 64g provided in the four corners of the second frame 64 are aligned in the XZ plane so that the long bolts 45 can pass through, forming four through holes 62a in the cell holder 62. Referring to Fig. 7(a), it can be seen that the screw holes 63g provided in the four corners of the first frame 63 and the screw holes 64g provided in the four corners of the second frame 64 are aligned as through holes 62a in the XZ plane.

[0077] Furthermore, the protrusions 63a provided on the lower parts of the left and right frames of the first frame 63 and the protrusions 64a provided on the lower parts of the left and right frames of the second frame 64 are aligned and abutted on the XZ plane. Also, referring to Fig. 7(b), it can be seen that the protrusions 63a provided on the lower parts of the left and right frames of the first frame 63 and the protrusions 64a provided on the lower parts of the left and right frames of the second frame 64 have upper surfaces 63a1, 64a1 that face the bottom surface that contacts the bottom plate 5 of the housing of the battery pack 1 aligned and flush with each other.

[0078] Furthermore, when each of the two cylindrical protrusions 63f provided on the left frame of the first frame 63 engages with each of the two cylindrical through holes 64f provided in the second frame 64 included in the cell assembly 41 (not shown) adjacent to the cell assembly 41 including the first frame 63 in the negative direction of the Y axis, the through hole 62a of the cell assembly 41 including the first frame 63 is aligned with the through hole 62a of the adjacent cell assembly 41, and the convex portions 63a, 64a of the cell assembly 41 including the first frame 63 are aligned with the convex portions 63a, 64a of the adjacent cell assembly 41.

[0079] The above-mentioned fitting of the first frame 63 and the second frame 64 constitutes a cell assembly stack 15 in which the cell assemblies 41 are stacked units. Moreover, for the convex group 65 of this cell assembly stack 15, the bottom surface that contacts the bottom plate 5 of the housing of the battery pack 1 and the top surface that faces the bottom surface are flush with each other. Moreover, in the housing of the battery pack 1 according to this embodiment, the locking members 51 that suppress movement of the convex portions 63a, 64a in the Z-axis direction perpendicular to the Y-axis direction are fixed to the inner surfaces of both side plates of the left side plate 7 and the right side plate 9 that sandwich both side surfaces of the cell assembly stack 15, and thus accommodate the cell assembly stack 15 as described above.

[0080] According to the cell holder 62 of the first embodiment, protrusions 63a, 64a are formed to protrude from both side surfaces of the cell holder 62 that constitute both side surfaces of the cell assembly stack 15. The protrusions 63a, 64a formed on both side surfaces of the cell holder 62 protrude from the side surfaces of some of the cell holders 62 that constitute at least a part of the left side surface of the cell assembly stack 15 and the side surfaces of some of the cell holders 62 that constitute at least a part of the right side surface of the cell assembly stack 15, and are locked in the Z-axis direction by locking members 51 fixed to the inner surfaces of both side plates of the left side plate 7 and the right side plate 9 of the housing, thereby preventing movement in the Z-axis direction.

[0081] Since the cell assembly stack 15 is formed by integrally forming a plurality of cell assemblies 41A, the protrusions 63a, 64a formed on each side of at least some of the cell holders 62 constituting the cell assembly stack 15 are locked in the Z-axis direction by locking members 51 fixed to the inner surfaces of both side plates of the left side plate 7 and the right side plate 9 of the housing of the battery pack 1, thereby preventing the movement of the cell assembly stack 15 within the housing in the Z-axis direction perpendicular to the Y-axis direction, which is the stacking direction. This makes it possible to provide a cell holder 62 and a housing of the battery pack 1 that can improve the vibration resistance and earthquake resistance of the cell assembly stack 15 in the Z-axis direction perpendicular to the stacking direction within the battery pack housing.

[0082] Furthermore, the movement of the cell assembly stack 15 in the battery pack housing in the Z-axis direction perpendicular to the stacking direction is prevented by the protrusions 63a, 64a of the cell holder 62 engaging with the locking member 51 of the housing when assembling the cell assembly stack 15 to be housed in the housing of the battery pack 1. That is, in this embodiment, the housing of the battery pack 1 is completed by attaching the top plate 3 to the bottom plate 5, the left plate 7, the front plate 11 and the rear plate 13 after they are integrated by bending and welding, and finally attaching the right plate 9, and at the same time as attaching the right plate 9, the remaining protrusions 63a, 64a on the right side surface of the cell holder 62 engage with the locking member 51 of the housing, thereby improving the vibration resistance and earthquake resistance of the cell assembly stack 15. Therefore, the vibration resistance and earthquake resistance of the cell assembly stack 15 in the Z-axis direction perpendicular to its stacking direction within the battery pack housing can be improved without reducing the assembly efficiency of the battery pack 1 by simply assembling the battery pack 1 without performing any special steps when assembling the battery pack 1.

[0083] Furthermore, in the cell holder 62 according to the first embodiment, the convex portions 63a, 64a are formed by protruding from the side surfaces of the first frame 63 and the second frame 64 themselves which constitute the side surfaces of the cell assembly stack 15. This makes it possible to improve the vibration resistance and earthquake resistance of the cell assembly stack 15 in the Z-axis direction perpendicular to the stacking direction within the battery pack casing without increasing the number of parts which constitute the cell assembly 41.

[0084] Next, a cell holder according to a second embodiment of the present invention will be described.

[0085] Fig. 10 is a perspective view illustrating a cell assembly 41A including a cell holder 62A according to the second embodiment, and corresponds to Fig. 6. Fig. 11(a) is a cross-sectional side view taken along line VV of the battery pack 1 shown in Fig. 3 when the cell assembly 41A according to the second embodiment is housed, and corresponds to Fig. 5(a). Fig. 11(b) is a detailed view of region B in Fig. 11(a), and corresponds to Fig. 5(b). Fig. 11(c) is a diagram showing a modified example of region B, which will be described later.

[0086] In the cell holder 62 of the first embodiment, protrusions 63a, 64a are provided on two side surfaces of each of the first frame 63 and the second frame 64 (see Figure 6), and the upper surfaces 63a1, 64a1 of the protrusions 63a, 64a are configured to at least partially abut against locking members 51 fixed to the left side plate 7 and the right side plate 9, respectively (see Figure 5).

[0087] In contrast, the cell holder 62A according to the second embodiment is composed of a first frame 63A and a second frame 64A. Recesses 63h, 64h are provided on the two lower side surfaces of the left and right frames of the first frame 63A and the second frame 64A, as shown in Fig. 10. The recesses 63h, 64h are provided below the left and right frames of the cell holder 62A, respectively, directly below a fixing means composed of a lever 63e and a recess 64e, and the lower surfaces 63h1, 64h1 of the recesses 63h, 64h at least partially abut against a locking member 51 fixed to the left side plate 7 and the right side plate 9, respectively, as shown in Fig. 11.

[0088] Therefore, the side of the cell holder 62A constituting at least a part of one side of the cell assembly stack 15, and the recesses 63h, 64h formed by recessing from the side of the cell holder 62A constituting at least a part of the other side of the cell assembly stack 15 are engaged in the Z-axis direction perpendicular to the one direction, which is the Y-axis direction, by the locking members 51 fixed to the inner surfaces of both side plates of the left side plate 7 and right side plate 9 of the housing that sandwich both side surfaces of the cell assembly stack 15, thereby preventing movement in the Z-axis direction perpendicular to the one direction.

[0089] According to the cell holder 62A of the second embodiment, recesses 63h, 64h are formed in both side surfaces of the cell holder 62A constituting both side surfaces of the cell assembly stack 15. The recesses 63h, 64h formed in both side surfaces of the cell holder 62A are recessed from the side surfaces of some of the cell holders 62A constituting at least a part of the left side surface of the cell assembly stack 15 and from the side surfaces of some of the cell holders 62A constituting at least a part of the right side surface of the cell assembly stack 15, and are engaged in the Z-axis direction by engaging members 51 fixed to the inner surfaces of both side plates of the left side plate 7 and the right side plate 9 of the housing, thereby preventing movement in the Z-axis direction.

[0090] Since the cell assembly stack 15 is formed by integrally forming a plurality of cell assemblies 41A, the recesses 63h, 64h formed on each side of at least some of the cell holders 62A constituting the cell assembly stack 15 are locked in the Z-axis direction by locking members 51 fixed to the inner surfaces of both side plates of the left side plate 7 and the right side plate 9 of the housing of the battery pack 1, thereby preventing the movement of the cell assembly stack 15 within the housing in the Z-axis direction perpendicular to the Y-axis direction, which is the stacking direction. This improves the vibration resistance and earthquake resistance of the cell assembly stack 15 in the Z-axis direction perpendicular to the stacking direction within the battery pack housing.

[0091] Furthermore, the movement of the cell assembly stack 15 in the battery pack housing in the Z-axis direction perpendicular to the stacking direction is prevented by the recesses 63h, 64h of the cell holder 62 engaging with the locking member 51 of the housing when assembling the cell assembly stack 15 to be housed in the housing of the battery pack 1. That is, in this embodiment, the housing of the battery pack 1 is completed by attaching the top plate 3 to the bottom plate 5, the left plate 7, the front plate 11 and the rear plate 13 to be integrated by bending and welding, and finally attaching the right plate 9, and at the same time as attaching the right plate 9, the remaining recesses 63h, 64h on the right side surface of the cell holder 62 engage with the locking member 51 of the housing, thereby improving the vibration resistance and earthquake resistance of the cell assembly stack 15. Therefore, the vibration resistance and earthquake resistance of the cell assembly stack 15 in the Z-axis direction perpendicular to its stacking direction within the battery pack housing can be improved without reducing the assembly efficiency of the battery pack 1 by simply assembling the battery pack 1 without performing any special steps when assembling the battery pack 1.

[0092] In the cell holder 62A according to the second embodiment, the recesses 63h, 64h are formed by recessing the first frame 63A and the second frame 64A themselves, which constitute the side surfaces of the cell assembly stack 15, from the side surfaces. This makes it possible to improve the vibration resistance and earthquake resistance of the cell assembly stack 15 in the Z-axis direction perpendicular to the stacking direction within the battery pack casing, without increasing the number of parts constituting the cell assembly 41A.

[0093] Furthermore, in the cell holder 62A according to the second embodiment, the recesses 63h, 64h are formed recessed on both side surfaces of the cell holder 62A, and therefore there are no protruding parts such as the convex parts 63a, 64a on the outer periphery. This makes it possible to make the housing of the battery pack 1 that houses the cell assembly stack 15 compact, thereby improving the energy density per unit volume of the battery pack 1.

[0094] In other words, according to the cell holder 62A of the second embodiment, like the cell holder 62 of the first embodiment, the vibration resistance and earthquake resistance of the battery pack 1 mounted on a load can be improved by taking into account the assembly efficiency of the battery pack 1, and at the same time, the volume of the housing of the battery pack 1 can be made compact, thereby improving the energy density per unit volume.

[0095] In the above first and second embodiments, the laminate cell 61 is described as encapsulating a lithium ion secondary battery. However, the secondary battery may be, for example, a nickel-hydrogen secondary battery, or in any case, may be another secondary battery in which the electrode laminate is housed together with an electrolyte in an exterior body made of a laminate film.

[0096] In the above-described first and second embodiments, the bottom plate 5, left side plate 7, front plate 11, and rear plate 13 constituting the housing of the battery pack 1 are integrally formed by bending a single zinc-plated steel plate. However, the bottom plate 5, left side plate 7, front plate 11, and rear plate 13 do not need to be formed from a single zinc-plated steel plate, and may be formed as separate bodies like the top plate 3 and right side plate 9, and then fastened by screws. In this case, the order in which the top plate 3, bottom plate 5, left side plate 7, right side plate 9, front plate 11, and rear plate 13, which are separate bodies, are attached does not limit the present invention.

[0097] In the above-mentioned first and second embodiments, the cell holders 62 and 62A are configured by two separate frames 63, 64 and 63A, 64A. However, the two frames constituting the cell holder do not have to be separate, and the two frames 63, 64 and 63A, 64A may be connected to each other at the bottom edge located in the negative direction of the Z axis among the four sides forming the outer periphery of each of the two frames 63, 64 and 63A, 64A, for example, and may be connected to each other in a foldable manner at the bottom edge by utilizing the flexibility of the molding resin. In any case, the cell holder of the present invention may be configured to hold the laminate cell 61 by a part corresponding to the first frame abutting one side of the laminate cell 61 and a part corresponding to the second frame abutting the other side.

[0098] In the above-described first and second embodiments, the protrusions 63a, 64a and the recesses 63h, 64h are provided on the left and right sides of the two frames 63, 64 and 63A, 64A that face each other in the X-axis direction, at the same positions in the Z-axis direction in contact with the bottom plate 5. However, the protrusions 63a, 64a and the recesses 63h, 64h do not have to be provided on the left and right sides of the two frames 63, 64 and 63A, 64A at the same positions in the Z-axis direction.

[0099] In any case, in the first embodiment, it is sufficient that the upper surface 63a1 of the convex portion 63a provided on the left side surface of the first frame 63 and the upper surface 64a1 of the convex portion 64a provided on the left side surface of the second frame 64 are flush with each other, and the upper surface 63a1 of the convex portion 63a provided on the right side surface of the first frame 63 and the upper surface 64a1 of the convex portion 64a provided on the right side surface of the second frame 64 are flush with each other. Also, in the second embodiment, it is sufficient that the lower surface 63h1 of the recess 63h provided on the left side surface of the first frame 63A and the lower surface 64h1 of the recess 64h provided on the left side surface of the second frame 64A are flush with each other, and the lower surface 63h1 of the recess 63h provided on the right side surface of the first frame 63A and the lower surface 64h1 of the recess 64h provided on the right side surface of the second frame 64A are flush with each other.

[0100] In the above-described first embodiment, the protrusions 63a and 64a are provided on the left and right sides of the two frames 63 and 64 that face each other in the X-axis direction. However, the protrusions 63a may be provided only on the left and right sides of the first frame 63, and the protrusions 64a may be provided only on the left and right sides of the second frame 64. The protrusions 63a may be provided only on one left side of the first frame 63 and the protrusions 64a may be provided only on the other right side of the second frame 64. The protrusions 63a may be provided only on the other right side of the first frame 63 and the protrusions 64a may be provided only on one left side of the second frame 64. In any case, it is sufficient that at least one protrusion is provided on both the two left and right sides of the cell holder 62 composed of the two frames 63 and 64. In this case, the protrusions 63a, 64a do not need to be provided in the directions perpendicular to the two side surfaces of the cell holder 62, as long as the protrusions 63a, 64a have locations for engaging with the engaging member 51 in the Z-axis direction.

[0101] In the above second embodiment, the recesses 63h and 64h are provided on the left and right sides of the two frames 63A and 64A facing each other in the X-axis direction. However, the recesses 63h may be provided only on the left and right sides of the first frame 63A, and the recesses 64h may be provided only on the left and right sides of the second frame 64A. The recesses 63h may be provided only on one left side of the first frame 63A and the recesses 64h may be provided only on the other right side of the second frame 64A, or the recesses 63h may be provided only on the other right side of the first frame 63A and the recesses 64h may be provided only on one left side of the second frame 64A. In any case, it is sufficient that at least one recess is provided on both the two left and right sides of the cell holder 62A composed of the two frames 63A and 64A. In this case, the recesses 63h, 64h do not need to be provided in the two side surfaces of the cell holder 62A in the directions perpendicular to each other, but it is sufficient that the recesses 63h, 64h have locations for engaging with the engaging member 51 in the Z-axis direction.

[0102] In the above first embodiment, the upper surfaces 63a1, 64a1 and the bottom surfaces 63a2, 64a2 (see FIGS. 5 and 8) of the protrusions 63a, 64a provided on each of the two frames 63, 64 have been described as being parallel to the bottom plate 5. However, the upper surfaces 63a1, 64a1 and the bottom surfaces 63a2, 64a2 of the protrusions 63a, 64a do not have to be parallel to the bottom plate 5. In any case, it is sufficient that the upper surfaces 63a1, 64a1 of the protrusions 63a, 64a can at least partially abut against the horizontal plate 51b of the L-shaped locking member 51 welded to the opposing left side plate 7 and right side plate 9.

[0103] In the above second embodiment, the lower surfaces 63h1, 64h1 (see FIG. 10) of the recesses 63h, 64h provided in the two frames 63A, 64A, respectively, are provided parallel to the bottom plate 5. However, the lower surfaces 63h1, 64h1 of the recesses 63h, 64h do not have to be parallel to the bottom plate 5. In any case, it is sufficient that the lower surfaces 63h1, 64h1 of the recesses 63h, 64h can at least partially abut against the horizontal plate 51b of the L-shaped locking member 51 welded to the opposing left side plate 7 and right side plate 9.

[0104] In the above first embodiment, the case has been described in which, of the two protrusion groups 65 formed along the stacking direction of the cell assembly stack 15, the protrusion group 65 on the left side plate 7 side abuts against the horizontal plates 51b of the three locking members 51 welded to the left side plate 7, and the protrusion group 65 on the right side plate 9 side abuts against the horizontal plates 51b of the two locking members 51 welded to the right side plate 9. However, the number and positions of the locking members 51 welded to the left side plate 7 and the number and positions of the locking members 51 welded to the right side plate 9 are not limited to this. In any case, it is sufficient that at least one locking member 51 is provided for the protrusion group 65 facing the left side plate 7, and at least one locking member 51 is provided for the protrusion group 65 facing the right side plate 9. Furthermore, on each of the left side plate 7 and the right side plate 9, one or both of the upper surfaces 63a1, 64a1 of the protrusions 63a, 64a of one cell holder 62 may be configured to abut against the locking member 51 and be covered by the locking member 51.

[0105] In the above-described second embodiment, of the two recessed groups (not shown) formed along the stacking direction of the cell assembly stack 15, the recessed group on the left side plate 7 abuts against the horizontal plate 51b of the three locking members 51 welded to the left side plate 7, and the recessed group on the right side plate 9 abuts against the horizontal plate 51b of the two locking members 51 welded to the right side plate 9. However, the number and positions of the locking members 51 welded to the left side plate 7 and the number and positions of the locking members 51 welded to the right side plate 9 are not limited to this. In any case, it is sufficient that at least one locking member 51 is provided for the recessed group facing the left side plate 7, and at least one locking member 51 is provided for the recessed group facing the right side plate 9. Also, both or one of the lower surfaces 63h1, 64h1 of the recesses 63h, 64h of one cell holder 62A may be configured to abut against the locking member 51 on each side of the left side plate 7 and the right side plate 9.

[0106] In the above first embodiment, as shown in Fig. 5(b), the horizontal plate 51b of the locking member 51 fixed to each inner surface of the left side plate 7 and the right side plate 9 abuts against the upper surfaces 63a1, 64a1 of the protrusions 63a, 64a of the cell holder 62 via the spacer 51c to suppress movement of the cell assembly stack 15 in the Z-axis direction within the battery pack housing. However, as shown in Fig. 5(c), by bending the end of the horizontal plate 51b in the Y-axis direction to form a hanging plate 51d that hangs down from the locking member 51 in the negative Z-axis direction, it is also possible to suppress movement of the cell assembly stack 15 in the Y-axis direction within the battery pack housing.

[0107] Similarly, in the above-described second embodiment, as shown in Fig. 11(b), the horizontal plate 51b of the locking member 51 fixed to each inner surface of the left side plate 7 and the right side plate 9 abuts against the lower surfaces 63h1, 64h1 of the recesses 63h, 64h of the cell holder 62A via the spacer 51c to suppress movement of the cell assembly stack 15 in the Z-axis direction within the battery pack housing. However, as shown in Fig. 11(c), by bending the end of the horizontal plate 51b in the Y-axis direction to form a hanging plate 51d hanging down from the locking member 51 in the negative Z-axis direction, it is also possible to suppress movement of the cell assembly stack 15 in the Y-axis direction within the battery pack housing.

[0108] In the above first embodiment, the fixing means for fixing the first frame 63 and the second frame 64, which are constituted by the levers 63e and the recesses 64e, and the convex portions 63a, 64a provided on the cell holder 62 are provided separately. However, the fixing means and the convex portions may be combined into one structure, and in any case, the present invention only requires that a portion corresponding to the fixing means for integrally fixing the first frame 63 and the second frame 64 and a portion corresponding to the convex portions that come into contact with the locking members 51 fixed to the left side plate 7 and the right side plate 9 are provided.

[0109] Fig. 12 is a perspective view illustrating a cell assembly 41B including a cell holder 62B according to a modification of the first embodiment in which the fixing means and the protrusion are combined as one structure, and corresponds to Fig. 6. Fig. 13(a) is a front view of the cell assembly 41B illustrated in Fig. 12 as viewed from the XZ plane, and corresponds to Fig. 7(a). Fig. 13(b) is a side view of the cell assembly 41B illustrated in Fig. 12 as viewed from the YZ plane, and corresponds to Fig. 7(b).

[0110] The cell holder 62B in the cell assembly 41B is composed of a first frame 63B and a second frame 64B. The cell holder 62B differs from the cell holder 62 according to the first embodiment in that, as a fixing means for fixing the first frame 63B and the second frame 64B, fixing means composed of a coupling member 70 is provided under each of the left and right frames of the cell holder 62B instead of fixing means composed of a lever 63e and a recess 64e, and in that the first frame 63B and the second frame 64B are provided with recesses 62b required for providing the coupling member 70.

[0111] Fig. 14(a) is a perspective view of the cell assembly 41B illustrated in Fig. 12 with the joining member 70 removed, and Fig. 14(b) is a perspective view of the joining member 70 alone. Also, Fig. 15(a) is a front view of the cell assembly 41B in the state shown in Fig. 14(a) as viewed from the XZ plane, and Fig. 15(b) is a side view of the cell assembly 41B in the state shown in Fig. 14(a) as viewed from the YZ plane.

[0112] As shown in Fig. 14(a), recesses 62b into which the connecting members 70 fit are formed below the left and right frames of the cell holder 62B. The pair of connecting members 70 fit into the recesses 62b, and the levers 63e provided above the left and right frames of the cell holder 62B fit into the recesses 64e, whereby the cell holder 62B holds the laminate cell 61 between the first frame 63B and the second frame 64B.

[0113] As shown in Fig. 14(b), each joining member 70 has a substantially U-shaped shape when viewed in the XY plane, and claws 70b are formed at the open ends of the tips of a pair of arms 70c in a direction facing each other. The arms 70c sandwich the first frame 63B and the second frame 64B from their outer surfaces along the Y-axis direction, and the claws 70b bite into both sides of the deepest parts of the recesses 62b in the X-axis direction, whereby each joining member 70 joins the lower parts of the first frame 63B and the second frame 64B. The joining member 70 constitutes a fixing means for clamping and fixing the first frame 63B and the second frame 64B on the side surfaces of the first frame 63B and the second frame 64B that constitute the side surfaces of the cell assembly stack 15.

[0114] Focusing on the XZ plane, as shown in Figure 13(b), the surface of the first frame 63B on the negative Y-axis side is flush with the surface of each connecting member 70 on the negative Y-axis side, and similarly, the surface of the second frame 64B on the positive Y-axis side is flush with the surface of each connecting member 70 on the positive Y-axis side.

[0115] 12 and 13(a), of the two side surfaces of the cell assembly 41B in the YZ plane, the coupling member 70 provided on the side surface in the X-axis positive direction has a protrusion 70a protruding in the X-axis positive direction from the side surface. An upper surface 70a1 of the protrusion 70a abuts against the locking member 51 fixed to the right side plate 9. Of the two side surfaces of the cell assembly 41B in the YZ plane, the coupling member 70 provided on the side surface in the X-axis negative direction has a protrusion 70a protruding in the X-axis negative direction from the side surface. An upper surface 70a1 of the protrusion 70a abuts against the locking member 51 fixed to the left side plate 7.

[0116] In this manner, in the cell holder 62B according to the modification of the first embodiment, the protrusion 70a is formed by a portion of the joining member 70 that protrudes from the side surfaces of the first frame 63B and the second frame 64B. According to the cell holder 62B according to the modification of the first embodiment, the fixing means and the protrusion 70a are formed by the joining member 70 that clamps and fixes the first frame 63B and the second frame 64B on the side surfaces of the first frame 63B and the second frame 64B, and the number of parts constituting the protrusion and the number of assembly steps can be reduced. In other words, since the protrusion 70a is realized by a part of the joining member 70 that is the fixing means, the number of components of the cell assembly 41B can be reduced, and the vibration resistance and earthquake resistance of the cell assembly stack 15 in the Z-axis direction perpendicular to the stacking direction in the battery pack housing can be inexpensively improved.

[0117] In the above modification of the first embodiment, the case where two connecting members 70 are provided on the cell holder 62B has been described. However, instead of the fixing means formed of the lever 63e and the recess 64e provided on the upper part of each of the left and right frames of the cell holder 62B, a fixing means formed of the connecting member 70 that connects to the recess 62b may be further provided, so that the cell holder 62B is provided with four connecting members 70. This configuration also provides the same effects as the above modification of the first embodiment.

[0118] In the above second embodiment, the fixing means for fixing the first frame 63A and the second frame 64A, which are constituted by the levers 63e and the recesses 64e, and the recesses 63h, 64h provided in the cell holder 62A are provided separately. However, the fixing means and the recesses may be combined into one structure. In any case, the present invention only requires that the device includes a portion corresponding to the fixing means for integrally fixing the first frame 63A and the second frame 64A, and a portion corresponding to the recess that comes into contact with the locking member 51 fixed to the left side plate 7 and the right side plate 9.

[0119] Fig. 16 is a perspective view illustrating a cell assembly 41C including a cell holder 62C according to a modification of the second embodiment in which the fixing means and the recess are combined as one structure, and corresponds to Fig. 6. Fig. 17(a) is a front view of the cell assembly 41C illustrated in Fig. 16 as viewed from the XZ plane, and corresponds to Fig. 7(a). Fig. 17(b) is a side view of the cell assembly 41C illustrated in Fig. 16 as viewed from the YZ plane, and corresponds to Fig. 7(b).

[0120] The cell holder 62C in the cell assembly 41C is composed of a first frame 63C and a second frame 64C. The cell holder 62C differs from the cell holder 62A according to the second embodiment in that, as a fixing means for fixing the first frame 63C and the second frame 64C, fixing means composed of a coupling member 70A is provided in the recess 62c instead of the fixing means composed of the lever 63e and the recess 64e directly above the recesses 63h, 64h below each of the left and right frames of the cell holder 62C.

[0121] The two connecting members 70A have the same shape as the connecting member 70, and the two recesses 62c have a depth greater than the depth of the recesses 63h, 64h in the cell holder 62A according to the second embodiment. The two connecting members 70A are inserted along the X-axis direction into the recesses 62c provided on the respective sides of the first frame 63C and the second frame 64C, and sandwich the first frame 63C and the second frame 64C in the Y-axis direction. As a result, the two connecting members 70A, together with the fixing means constituted by the lever 63e and the recess 64e above the left and right frames of the cell holder 62C, fix the first frame 63C and the second frame 64C together, and maintain the state in which the laminate cell 61 is held between the first frame 63C and the second frame 64C.

[0122] One of the two connecting members 70A is provided on the side of the cell assembly 41C in the X-axis positive direction, out of two side surfaces in the YZ plane, below the fixing means formed by the lever 63e and the recess 64e, and connects the right frames extending in the Z-axis direction on the X-axis positive direction side of the first frame 63C and the second frame 64C. The other of the two connecting members 70A is provided on the side of the cell assembly 41C in the X-axis negative direction, out of two side surfaces in the YZ plane, below the fixing means formed by the lever 63e and the recess 64e, and connects the left frames extending in the Z-axis direction on the X-axis negative direction side of the first frame 63C and the second frame 64C.

[0123] Focusing on the XZ plane, as shown in Figure 17(b), the surface of the first frame 63C on the negative Y-axis side and the surface of the connecting member 70A on the negative Y-axis side are flush with each other, and similarly, the surface of the second frame 64C on the positive Y-axis side and the surface of the connecting member 70A on the positive Y-axis side are flush with each other.

[0124] Moreover, when focusing on the YZ plane, as shown in Fig. 17(a), the cell holder 62C has a recess 62c into which the coupling member 70A is inserted on the side on the X-axis positive side of the two side surfaces in the YZ plane of the cell assembly 41C. A lower surface 62c1 of the recess 62c abuts against the locking member 51 fixed to the right side plate 9 (see Fig. 11). Moreover, the cell holder 62C has a recess 62c into which the coupling member 70A is inserted on the side on the X-axis negative side of the two side surfaces in the YZ plane of the cell assembly 41C. A lower surface 62c1 of the recess 62c abuts against the locking member 51 fixed to the left side plate 7 (see Fig. 11).

[0125] In this manner, in the modified example of the second embodiment, the coupling member 70A constituting the fixing means holds the first frame 63C and the second frame 64C between the recess 62c formed by recessing the first frame 63C and the second frame 64C constituting the side surfaces of the cell assembly stack 15, leaving a recessed portion of the recess 62c that is engaged with the engaging member 51. According to this configuration, the coupling member 70A is provided in the recess of the recess 62c and does not protrude to the outer periphery of the cell assembly 41C, so that the size of the cell assembly stack 15 can be reduced. Therefore, the housing of the battery pack 1 that houses the cell assembly stack 15 can be made compact, and the energy density per unit volume of the battery pack 1 can be improved.

[0126] In the above modification of the second embodiment, the case where two connecting members 70A are provided on the cell holder 62C has been described. However, the fixing means formed of the lever 63e and the recess 64e provided on the upper part of each of the left and right frames of the cell holder 62C may also be configured to further include a connecting portion between the fixing means formed of the connecting member 70A and the recess 62c, so that the cell holder 62C is provided with four connecting members 70A that are integrated with the four recesses 62c. This configuration also provides the same effects as the above modification of the second embodiment.

[0127] Furthermore, in the above first embodiment and modified example, a configuration is disclosed in which only protruding convex portions are formed on both side surfaces of the cell holder that constitutes both side surfaces of the cell assembly stack 15 formed by stacking cell assemblies 41, 41B in one direction to form an integral unit, and in the above second embodiment and modified example, a configuration is disclosed in which only recessed portions are formed on both side surfaces of the cell holder that constitutes both side surfaces of the cell assembly stack 15 formed by stacking cell assemblies 41A, 41C in one direction to form an integral unit.

[0128] The present invention is not limited to these, and for example, a convex portion may be formed protruding from one of the two side surfaces of the cell holder constituting both side surfaces of the cell assembly stack 15, and a concave portion may be formed recessed into the other side surface.In this case, the convex portion and the concave portion are each engaged in a direction perpendicular to the one direction by engaging members fixed to the inner surfaces of both side plates of the housing that sandwich both side surfaces of the cell assembly stack 15, thereby preventing movement in the direction perpendicular to the one direction.

[0129] Furthermore, the housing of the battery pack 1 according to this embodiment can accommodate not only the cell assembly 41 including the cell holder 62 according to the first embodiment, but also the cell assembly 41A including the cell holder 62A according to the second embodiment, the cell assembly 41B including the cell holder 62B according to the modification of the first embodiment, and the cell assembly 41C including the cell holder 62C according to the modification of the second embodiment. Therefore, the housing of the battery pack 1 according to this embodiment can provide a housing of the battery pack 1 capable of improving the vibration resistance and earthquake resistance of the cell assembly stack 15 including cell assemblies of various shapes in the Z-axis direction perpendicular to the stacking direction in the battery pack housing. [Industrial Applicability]

[0130] The cell holders 62, 62A, 62B, 62C and the housing of each battery pack 1 according to the present invention have vibration countermeasures taken in consideration of the assembly efficiency of the housing of the battery pack 1, and therefore have high industrial applicability. [Explanation of symbols]

[0131] 1: Battery pack 3: Tabletop 5: Bottom plate 7:Left side board 9: Right side board 11: Front panel 13: Rear plate 15: Cell assembly stack 41, 41A, 41B, 41C: Cell assembly 51: Locking member 63a, 64a: convex part 63h, 64h: recess 65: Convex group 61: Laminated cell 62, 62A, 62B, 62C: Cell holder 63, 63A, 63B, 63C: First frame 64, 64A, 64B, 64C: Second frame

Claims

1. A cell holder for holding a laminate cell in a cell assembly constituting a cell assembly stack housed in a battery pack housing, comprising: a first frame that holds the laminate cell from one side of the laminate cell; a second frame that holds the laminate cell from the other surface side of the laminate cell; a fixing means for fixing the first frame and the second frame to maintain a state of the cell assembly in which the laminate cell is sandwiched between the first frame and the second frame; and The cell assemblies are stacked in one direction to be integrally formed, and the cell assembly stack is formed so as to protrude or recess on both side surfaces of the cell holder constituting both side surfaces, and the cell assembly stack is formed so as to protrude or recess on the side surface of the cell holder constituting at least a part of one side surface of the cell assembly stack and the side surface of the cell holder constituting at least a part of the other side surface of the cell assembly stack. The protrusions or recesses are engaged in a direction perpendicular to the one direction by engaging members fixed to the inner surfaces of both side plates of the housing that sandwich both side surfaces of the cell assembly stack, thereby preventing movement in a direction perpendicular to the one direction. A cell holder comprising:

2. The cell holder as described in claim 1, characterized in that the convex portion or concave portion is formed by protruding or recessing from the side surface of at least one of the first frame and the second frame themselves, which constitute the side surface of the cell assembly stack.

3. 2. The cell holder according to claim 1, wherein the protrusion is formed as a part of the fixing means.

4. the fixing means is constituted by a connecting member that clamps and fixes the first frame and the second frame on side surfaces of the first frame and the second frame that constitute side surfaces of the cell assembly stack, 4. The cell holder according to claim 3, wherein the protrusion is formed by a portion of the connecting member that protrudes from the side surfaces of the first frame and the second frame.

5. The cell holder described in claim 2, characterized in that the fixing means is constituted by a joining member that clamps and fixes the first frame and the second frame within a recess formed by recessing the side surfaces of the first frame and the second frame that constitute the side surfaces of the cell assembly stack, leaving a recess portion of the recess that engages with the engaging portion.

6. A cell holder for holding a laminate cell in a cell assembly constituting a cell assembly stack housed in a battery pack housing, comprising: a first frame that holds the laminate cell from one side of the laminate cell; a second frame that holds the laminate cell from the other surface side of the laminate cell; a fixing means for fixing the first frame and the second frame to maintain a state of the cell assembly in which the laminate cell is sandwiched between the first frame and the second frame; and a convex portion formed by protruding from one of both side surfaces of the cell holder constituting both side surfaces of the cell assembly stack in which the cell assemblies are stacked in one direction and integrally constructed, and a concave portion formed by recessing into the other of the both side surfaces, the convex portion formed by protruding from the one side surface of the cell holder constituting at least a part of the one side surface of the cell assembly stack, and the concave portion formed by recessing from the other side surface of the cell holder constituting at least a part of the other side surface of the cell assembly stack, are engaged in a direction perpendicular to the one direction by engaging members fixed to inner surfaces of both side plates of the housing that sandwich both side surfaces of the cell assembly stack, and the convex portion and the concave portion are prevented from moving in a direction perpendicular to the one direction. A cell holder comprising:

7. A housing for a battery pack that houses a cell assembly stack formed by stacking cell holders described in any one of claims 1 to 6, wherein the locking member that prevents movement of the convex or concave portion in a direction perpendicular to the one direction is fixed to the inner surface of both side plates that sandwich both side surfaces of the cell assembly stack.

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