battery pack

Abstract

To restrain a decrease in strength of a terminal member.SOLUTION: A terminal member 500 is electrically connected to at least one battery cell among a plurality of battery cells. A holder 600 is located at an end portion of a laminate, and the terminal member 500 can be fixed by inserting the terminal member 500 into the holder 600 in a first direction. The terminal member 500 includes a first portion 510 and a second portion 520. The first portion 510 extends in a direction perpendicular to the first direction. The second portion 520 bends from an end portion of the first portion 510 toward the first direction, and extends along the first direction. The holder 600 includes a claw portion 630. At least a part of the claw portion 630 faces the second portion 520. The second portion 520 is provided with an opening 521 that is arranged so as not to reach the first portion 510 and can engage with the claw portion 630.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present technology relates to a battery pack. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2019-3737 (Patent Document 1) is a prior art document that discloses the configuration of an energy storage module. The energy storage module described in Patent Document 1 includes a first external connection bus bar and an external connection bus bar protector. The first external connection bus bar includes one end and a bolt fastening portion that is bent at the other end so as to be perpendicular to the one end. The external connection bus bar protector includes a fixing claw. The first external connection bus bar has an opening that engages with the fixing claw at a bent portion that is continuous with the bolt fastening portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-3737 Summary of the Invention [Problem to be solved by the invention]

[0004] In the energy storage module described in Patent Document 1, an opening for engaging the terminal member with a holder that fixes the terminal member is provided so as to connect a first flat portion of the terminal member that is electrically connected to the battery cell and a second flat portion that bends from an end of the first flat portion. As a result, the opening occupies a large area in the terminal member, which may reduce the strength of the terminal member.

[0005] The present technology has been made to solve the above-mentioned problems, and has an object to provide a battery pack that can suppress a decrease in the strength of terminal members. [Means for solving the problem]

[0006] The present technology provides the following assembled battery. [1] a stack in which a plurality of battery cells are arranged side by side; a terminal member electrically connected to at least one battery cell among the plurality of battery cells; a holder positioned at an end of the laminate and capable of fixing the terminal member by inserting the terminal member from a first direction; the terminal member includes a first portion extending in a direction perpendicular to the first direction, and a second portion bent from an end of the first portion toward the first direction and extending along the first direction; the holder includes a claw portion, at least a portion of which faces the second portion; The second portion has an opening that is disposed so as not to reach the first portion and that can be engaged with the claw portion. [2] the plurality of battery cells are arranged side by side in a second direction perpendicular to the first direction, The battery pack according to [1], wherein the holder is located at an end of the stack in the second direction. [3] The battery pack according to [1] or [2], wherein the claw portion is located on the opposite side of the second portion from the side where the stack is disposed. [4] the holder is provided with a space capable of receiving the second portion, The battery pack according to any one of [1] to [3], wherein the holder includes a plurality of protrusions that sandwich the second portion in a direction perpendicular to the first direction in the space. [5] Further comprising a bolt member; The battery pack according to any one of [1] to [4], wherein the first portion of the terminal member is provided with a through hole through which the bolt member can be inserted. [Effects of the Invention]

[0007] According to the present technology, it is possible to suppress a decrease in the strength of the terminal member. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view showing a configuration of a battery pack according to an embodiment of the present technology; [Figure 2] 1 is a perspective view showing an internal structure of a battery pack excluding a cover member of the battery pack according to an embodiment of the present technology; [Figure 3] 1 is a perspective view showing a configuration of a battery cell included in a battery pack according to an embodiment of the present technology; [Figure 4] 1 is a perspective view illustrating a connection state between a terminal member and a holder included in a battery pack according to an embodiment of the present technology; [Figure 5] 5 is a partial cross-sectional view of the terminal member and the holder of FIG. 4, as viewed from the direction of the arrow VV. [Figure 6] 1 is a perspective view illustrating a state in which a terminal member according to an embodiment of the present technology is inserted into a holder; [Figure 7] 1 is a cross-sectional perspective view showing a configuration around a claw portion of a holder according to an embodiment of the present technology; [Figure 8] 8 is a partial cross-sectional view of the holder of FIG. 5, as seen from the direction of the arrows along line VIII-VIII. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present technology will be described. Note that the same or corresponding parts are denoted by the same reference characters, and description thereof may not be repeated.

[0010] In the embodiments described below, when numbers, amounts, etc. are mentioned, the scope of the present technology is not necessarily limited to those numbers, amounts, etc., unless otherwise specified. Furthermore, in the embodiments described below, each component is not necessarily essential to the present technology, unless otherwise specified. Furthermore, the present technology is not necessarily limited to those that achieve all of the effects and advantages mentioned in the present embodiments.

[0011] In this specification, the terms "comprise," "include," and "have" are open-ended. That is, when a certain feature is included, other features may or may not be included.

[0012] Furthermore, when geometric terms and terms expressing positional and directional relationships are used in this specification, such as "parallel," "orthogonal," "45° diagonal," "coaxial," and "along," these terms allow for manufacturing errors and slight variations. When terms expressing relative positional relationships, such as "upper side" and "lower side," are used in this specification, these terms are used to indicate relative positional relationships in a single state, and the relative positional relationships can be reversed or rotated to any angle depending on the installation direction of each mechanism (for example, by turning the entire mechanism upside down).

[0013] In this specification, the term "battery" is not limited to lithium-ion batteries, but may include other batteries such as nickel-metal hydride batteries and sodium-ion batteries. In this specification, the term "electrode" may collectively refer to a positive electrode and a negative electrode.

[0014] In this specification, the term "battery cell" is not necessarily limited to a rectangular cell, but may also include cells of other shapes, such as a cylindrical cell.

[0015] Furthermore, the "battery pack" in this specification can be installed in hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), etc. However, the use of the "battery pack" in this specification is not limited to in-vehicle use.

[0016] In the drawings, the direction in which the positive and negative terminals of the battery cells are aligned is the X direction as the third direction, the direction in which the multiple battery cells are aligned is the Y direction as the second direction, and the direction in which the terminal members are inserted into the holder is the Z direction as the first direction. Also, to facilitate understanding of the present technology, the dimensional ratios of each component in the drawings may be changed from the actual dimensional ratios.

[0017] Fig. 1 is a perspective view showing a configuration of a battery pack according to an embodiment of the present technology, Fig. 2 is a perspective view showing an internal structure of the battery pack according to an embodiment of the present technology, excluding a cover member of the battery pack.

[0018] As shown in FIGS. 1 and 2, the battery pack 1 in this embodiment includes a stack 10, an end plate 200, a restraining member 300, a cover member 400, a terminal member 500, a holder 600, and a bolt member 700.

[0019] The stack 10 includes a plurality of battery cells 100. The plurality of battery cells 100 are arranged side by side in a second direction (Y direction) perpendicular to a first direction (Z direction). Separators (not shown) are interposed between the plurality of battery cells 100.

[0020] The laminate 10 is sandwiched between two end plates 200. The laminate 10 according to this embodiment is pressed against the end plates 200 and is restrained between the two end plates 200.

[0021] The end plates 200 are provided on both ends of the stack 10 in the Y direction. The end plates 200 are fixed to a base such as a pack case that houses the battery pack 1. The end plates 200 are made of, for example, aluminum or iron.

[0022] The restraining members 300 are provided on both ends of the stacked body 10 and the end plates 200 in the X direction. When the restraining members 300 are engaged with the end plates 200 while a compressive force in the Y direction is applied to the stacked body 10 and end plates 200 arranged side by side, and the compressive force is then released, a tensile force acts on the restraining members 300 connecting the two end plates 200. In reaction to this, the restraining members 300 press the two end plates 200 in a direction that brings them closer to each other. As a result, the restraining members 300 restrain the stacked body 10 in the Y direction.

[0023] 1, the cover member 400 protects the electrical connections of the battery pack 1. The cover member 400 is made of an insulating resin material.

[0024] The cover member 400 includes a first cover member 410 and a second cover member 420. The first cover member 410 is positioned above the stack 10 and protects the electrical connections of the stack 10. The second cover member 420 is positioned above the terminal members 500 and the holder 600 and protects the electrical connections of the terminal members 500.

[0025] 2, the terminal members 500 are provided to electrically connect the laminate 10 to external terminals (not shown). The terminal members 500 are arranged on both sides of the laminate 10 in the Y direction. The terminal members 500 are made of plate-shaped conductors. The terminal members 500 include a positive side terminal member 500a and a negative side terminal member 500b.

[0026] The terminal member 500 is electrically connected to at least one battery cell 100 among the plurality of battery cells 100. In the present embodiment, the positive side terminal member 500a and the negative side terminal member 500b are each electrically connected to one battery cell 100 located at an end of the plurality of battery cells 100.

[0027] The holder 600 is provided to support the terminal members 500 and protect the electrical connection of the terminal members 500. The holder 600 is located at an end of the laminate 10. In the present embodiment, the holder 600 is located at an end of the laminate 10 in the second direction (Y direction).

[0028] The holder 600 has insulating properties. The holder 600 is connected to the end plate 200 by a known method such as bolt fastening. The terminal member 500 is fixed to the holder 600. The method of fixing the terminal member 500 to the holder 600 will be described later.

[0029] The bolt member 700 is provided to electrically connect the terminal member 500 and the external terminal. The bolt member 700 is screwed together with the terminal member 500 and the external terminal sandwiched between the bolt member 700 and a nut member (not shown). This electrically connects the terminal member 500 and the external terminal.

[0030] FIG. 3 is a perspective view showing a configuration of a battery cell included in a battery pack according to an embodiment of the present technology.

[0031] As shown in FIG. 3, the battery cell 100 according to this embodiment includes an electrode terminal 110, a case 120, and a gas release valve .

[0032] The electrode terminal 110 is formed on the case 120. The electrode terminal 110 has a positive electrode terminal 111 and a negative electrode terminal 112. The positive electrode terminal 111 and the negative electrode terminal 112 are arranged side by side in the third direction (X direction).

[0033] The case 120 is a container that houses an electrode assembly and an electrolyte (not shown). The case 120 has a substantially rectangular parallelepiped shape. The case 120 is made of aluminum, an aluminum alloy, iron, or an iron alloy such as stainless steel.

[0034] As shown in FIG. 3, the case 120 has a sealing plate 121, a bottom surface 122, a pair of long side walls 123, and a pair of short side walls .

[0035] The sealing plate 121 forms the upper surface of the case 120. The electrode terminals 110 are disposed on the sealing plate 121. The bottom surface 122 faces the sealing plate 121 in the Z direction.

[0036] The pair of long side walls 123 and the pair of short side walls 124 form the side surfaces of the case 120. The pair of long side walls 123 and the pair of short side walls 124 intersect with the sealing plate 121 and the bottom surface 122, respectively. The pair of long side walls 123 face each other in the Y direction with the electrode body therebetween. The pair of short side walls 124 face each other in the X direction with the electrode body therebetween. Each of the pair of long side walls 123 has a larger area than each of the pair of short side walls 124.

[0037] The gas exhaust valve 130 breaks when the pressure inside the case 120 reaches or exceeds a predetermined value, thereby allowing the gas inside the case 120 to be exhausted to the outside of the case 120.

[0038] Fig. 4 is a perspective view showing a connection state between a terminal member and a holder included in a battery pack according to an embodiment of the present technology. Fig. 5 is a partial cross-sectional view of the terminal member and the holder of Fig. 4 as viewed from the direction of the VV line arrow. Fig. 6 is a perspective view showing a state in which the terminal member according to an embodiment of the present technology is inserted into the holder. Note that, in the following description, reference will be made to the configuration of the positive side terminal member 500a side of the terminal member 500, but the structure of the present technology can also be configured in a similar manner on the negative side terminal member 500b side.

[0039] As shown in FIGS. 4 to 6, the terminal member 500 includes a first portion 510 and a second portion 520. As shown in FIG.

[0040] The first portion 510 extends in a direction perpendicular to the first direction (Z direction). In this embodiment, the first portion 510 extends in a second direction (Y direction). One end of the first portion 510 is electrically connected to the battery cell 100. The other end of the first portion 510 extends in the second direction (Y direction) in a direction away from the stack 10.

[0041] The first portion 510 extends on the XY plane. The first portion 510 abuts against the abutment surface 601 of the holder 600 and the flat portion of the bolt member 700.

[0042] The first portion 510 is provided with a through-hole 511 through which the bolt member 700 can be inserted. The threaded portion of the bolt member 700 is inserted into the through-hole 511.

[0043] The second portion 520 is bent in a first direction (Z direction) from an end of the first portion 510. In the present embodiment, the second portion 520 is bent in the first direction (Z direction) at a bending point P located at the other end of the first portion 510 in the Y direction.

[0044] The second portion 520 is along the first direction (Z direction). In this embodiment, the second portion 520 is along the XZ plane.

[0045] An opening 521 is provided in the second portion 520. The opening 521 is engageable with a claw portion 630, which will be described later. The opening 521 provided in the second portion 520 is positioned so as not to reach the first portion 510.

[0046] In this embodiment, opening 521 has a rectangular shape with rounded corners when viewed from the Y direction. However, opening 521 is not limited to this shape. The shape of opening 521 may be circular, elliptical, or the like, as long as it can engage with claw portion 630.

[0047] The opening 521 penetrates the second portion 520, but is not limited to this. The opening 521 may be configured by providing a recess in the surface of the second portion 520 on the side where the claw portion 630 is arranged.

[0048] 5 and 6, the holder 600 is provided with a space 610 capable of receiving the second portion 520 of the terminal member 500. The second portion 520 is housed in the space 610.

[0049] Holder 600 includes a base portion 620 and claw portions 630. Base portion 620 is a portion that supports claw portions 630. Base portion 620 is located below holder 600 in the first direction (Z direction).

[0050] The claw portion 630 has a pillar portion 631 and a tip portion 632. The pillar portion 631 extends upward from the base portion 620 in the first direction (Z direction).

[0051] The tip portion 632 protrudes from the column portion 631 toward the second portion 520 above the column portion 631 in the first direction (Z direction).

[0052] When the terminal member 500 is assembled to the holder 600, at least a portion of the claw portion 630 faces the second portion 520. In the present embodiment, at least a portion of the pillar portion 631 faces the lower end portion of the second portion 520 in the first direction (Z direction), and the tip portion 632 faces the opening 521 of the second portion.

[0053] The claw portion 630 engages with the opening 521 of the second portion 520. Specifically, when the terminal member 500 is assembled to the holder 600, the tip portion 632 of the claw portion 630 is positioned in the inner space of the opening 521 in the second direction (Y direction), and at least a part of the tip portion 632 is aligned with the second portion 520 in the first direction (Z direction), thereby engaging with the opening 521 of the second portion 520.

[0054] 6, the terminal member 500 can be fixed to the holder 600 by inserting it from a first direction (Z direction). In this embodiment, the second portion 520 of the terminal member 500 is inserted into the space 610 of the holder 600 from the DR1 direction, and the opening 521 and the claw portion 630 are engaged with each other, thereby fixing the terminal member 500 to the holder 600.

[0055] FIG. 7 is a cross-sectional perspective view showing a configuration around a claw portion of a holder according to an embodiment of the present technology.

[0056] As shown in FIGS. 5 to 7 , when the second portion 520 is inserted into the space 610, the lower end portion of the second portion 520 in the first direction (Z direction) comes into contact with the tip portion 632 of the claw portion 630. As a result, the claw portion 630 elastically deforms in a direction away from the second portion 520 (direction DR2 in FIG. 7 ) with the base portion 620 as a fulcrum. When the second portion 520 is further inserted into the space 610, the tip portion 632 enters the inner space of the opening 521. As a result, the elastic deformation of the claw portion 630 returns to its original state, and the tip portion 632 moves in a direction toward the second portion 520 with the base portion 620 as a fulcrum (direction DR3 in FIG. 7 ). As a result, the tip portion 632 engages with the opening 521.

[0057] The claw portion 630 is located on the opposite side to the side on which the laminate 10 is disposed, as viewed from the second portion 520. In the present embodiment, the laminate 10, the second portion 520 of the terminal member 500, and the claw portion 630 of the holder 600 are aligned in this order in the Y direction, as shown in Figures 2, 5, and 7.

[0058] If the claw portion 630 is provided on the laminate 10 side when viewed from the second part 520, it is necessary to secure a space between the laminate 10 and the second part 520 in the second direction (Y direction) sufficient for the movement of the claw portion 630, taking into account the movement of the claw portion 630 due to elastic deformation when the claw portion 630 engages with the opening 521.

[0059] On the other hand, since the claw portions 630 in this embodiment are located on the opposite side of the stack 10 as viewed from the second portion 520, there is no need to ensure a space between the stack 10 and the second portion 520 in the second direction (Y direction) that is large enough for the claw portions 630 to move in the second direction (Y direction). Therefore, by positioning the claw portions 630 on the opposite side of the stack 10 as viewed from the second portion 520, the holder 600 can be made shorter in the second direction (Y direction) compared to when the claw portions 630 are provided on the stack 10 side as viewed from the second portion 520. As a result, the battery pack 1 can be made smaller.

[0060] Fig. 8 is a partial cross-sectional view of the holder of Fig. 5 as seen from the direction of the arrows VIII-VIII. As shown in Fig. 8, holder 600 includes first partition plate 640, second partition plate 641, and a plurality of protrusions 650.

[0061] The first partition plate 640 extends in the XZ plane. When viewed from the second portion 520, the first partition plate 640 is located on the stacked body 10 side. The second partition plate 641 extends in the XZ plane. When viewed from the second portion 520, the second partition plate 641 is located on the opposite side to the side on which the stacked body 10 is placed.

[0062] The plurality of protrusions 650 protrude from each of the first partition plate 640 and the second partition plate 641. The plurality of protrusions 650 are arranged such that the protrusions aligned in the second direction (Y direction) among the plurality of protrusions 650 face each other.

[0063] The plurality of protrusions 650 sandwich the second portion 520 in the space 610 from a direction perpendicular to the first direction (Z direction). In the present embodiment, the plurality of protrusions 650 sandwich the second portion 520 from the second direction (Y direction). Because the second portion 520 is sandwiched between the plurality of protrusions 650, the positioning of the second portion 520 becomes easier, and the claw portion 630 easily engages with the opening 521.

[0064] In the battery pack 1 according to one embodiment of the present technology, an opening 521 is provided in the second portion 520 of the terminal member 500 so as not to reach the first portion 510 and to engage with the claw portion 630 of the holder 600. This allows the opening area of ​​the opening 521 to be smaller than when an opening is provided so as to connect the first portion 510 and the second portion 520 of the terminal member 500, thereby suppressing a decrease in the strength of the terminal member 500 due to the provision of the opening 521.

[0065] In the battery pack 1 according to one embodiment of the present technology, the direction in which the terminal member 500 is inserted into the holder 600 is a direction (Z direction) perpendicular to the stacking direction of the battery cells 100, and the holder 600 is positioned at the end of the stack 10 in the stacking direction of the battery cells 100, so that the second portion 520 of the terminal member 500 that engages with the holder 600 can be positioned along the direction (Z direction) perpendicular to the stacking direction of the battery cells 100, thereby making it possible to configure a battery pack 1 that is short in length in the stacking direction (Y direction) of the battery cells 100.

[0066] In the battery pack 1 according to the embodiment of the present technology, compared to when the claw portion 630 is arranged on the same side of the second portion 520 as the side on which the stack 10 is arranged, there is no need to provide a space in the holder 600 with a movement width sufficient for the claw portion 630 to elastically deform in order to engage with the opening 521, and therefore the holder 600 can be made smaller. As a result, the battery pack 1 can be made smaller.

[0067] In the battery pack 1 according to one embodiment of the present technology, the second portion 520 is clamped by a plurality of protrusions 650 of the holder 600, thereby stably positioning the terminal member 500 relative to the holder 600 and facilitating engagement of the claw portion 630 with the opening 521.

[0068] In the battery pack 1 according to one embodiment of the present technology, the opening 521 of the terminal member 500 is arranged so as not to reach the first portion 510. Therefore, even if a through hole 511 for inserting the bolt member 700 is provided in the first portion 510, a decrease in the strength of the terminal member 500 can be suppressed compared to when an opening is provided so as to connect the first portion 510 and the second portion 520.

[0069] Although the embodiments of the present technology have been described above, the embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present technology is defined by the claims, and it is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0070] 1 battery pack, 10 laminate, 100 battery cell, 110 electrode terminal, 111 positive electrode terminal, 112 negative electrode terminal, 120 case, 121 sealing plate, 122 bottom surface, 123 pair of long side walls, 124 pair of short side walls, 130 gas release valve, 200 end plate, 300 restraint member, 400 cover member, 410 first cover member, 420 second cover member, 500 terminal member, 500a positive side terminal member, 500b negative side terminal member, 510 first portion, 511 through hole, 520 second portion, 521 opening, 600 holder, 610 space, 620 base portion, 630 claw portion, 631 column portion, 632 tip portion, 640 first partition plate, 641 second partition plate, 650 Protrusion, 700 bolt member, P bend point.

Claims

1. a stack in which a plurality of battery cells are arranged side by side; a terminal member electrically connected to at least one battery cell among the plurality of battery cells; a holder positioned at an end of the laminate and capable of fixing the terminal member by inserting the terminal member from a first direction; the terminal member includes a first portion extending in a direction perpendicular to the first direction, and a second portion bent from an end of the first portion toward the first direction, electrically connected to the at least one battery cell via the first portion, and extending along the first direction; the holder includes a claw portion, at least a portion of which faces the second portion; The second portion has an opening that is disposed so as not to reach the first portion and is engageable with the claw portion, the plurality of battery cells are arranged side by side in a second direction perpendicular to the first direction, the holder is located at an end of the stack in the second direction, the tab portion is located on an opposite side to a side on which the stack is disposed as viewed from the second portion in the second direction.

2. the holder is provided with a space capable of receiving the second portion, The battery pack according to claim 1 , wherein the holder includes a plurality of protrusions that sandwich the second portion in a direction perpendicular to the first direction in the space.

3. Further comprising a bolt member; 3. The battery assembly according to claim 1, wherein the first portion of the terminal member is provided with a through hole through which the bolt member can be inserted.

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