Electricity storage device

Abstract

The invention provides a power storage device capable of suppressing an increase in size of the power storage device due to a structure of a portion where an end plate and a belt are connected. The power storage device (100) is provided with: a plurality of power storage cells (10) arranged in the X direction; a first end plate (20a) and a second end plate (20b) that sandwich the plurality of power storage cells (10) in the X direction; and a belt (30). The belt (30) includes a belt main body portion (31) and a contact plate (32) provided at an end portion of the belt main body portion (31) in an X direction. One end and the other end of the contact plate (32) in the Y direction are respectively provided with a first convex part (33) and a second convex part (34). The first end plate (20a) is provided with a first concave part (25) which is embedded with the first convex part (33) and a second concave part (26) which is embedded with the second convex part (34).

Description

Technical Field

[0001] This disclosure relates to energy storage devices. Background Technology

[0002] Japanese Patent Application Publication No. 2013-069657 (Patent Document 1) discloses an energy storage device comprising: a plurality of energy storage elements arranged in a predetermined direction; a pair of end plates clamping the plurality of energy storage elements in the predetermined direction; and a connecting member extending in the predetermined direction and connected to the pair of end plates. Patent Document 1 describes an example in which the end plates and the connecting member are fastened together by rivets.

[0003] [Existing Technical Documents]

[0004] [Patent Literature]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2013-069657 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] In Patent Document 1 mentioned above, as described, an example is described where the end plate and the connecting component (band) are fastened together by rivets. In this case, space is required for arranging the rivets, which results in a larger energy storage device.

[0008] This disclosure was made to solve the above-mentioned problems, and its purpose is to provide an energy storage device that can suppress the large size of the energy storage device due to the structure of the part connecting the end plate and the belt.

[0009] Methods for solving problems

[0010] One aspect of the energy storage device disclosed herein includes: a plurality of energy storage units arranged in an arrangement direction; a first end plate and a second end plate sandwiching the plurality of energy storage units in the arrangement direction; and a belt connecting the plurality of energy storage units, the first end plate, and the second end plate. The belt includes a belt body extending along the arrangement direction of the plurality of energy storage units and a connecting portion disposed at the end of the belt body in the arrangement direction. The connecting portion is formed to extend in a cross direction intersecting the arrangement direction. A first fitting portion and a second fitting portion are formed at one end and the other end in the cross direction of the connecting portion, respectively. A first fitted portion that fits into the first fitting portion and a second fitted portion that fits into the second fitting portion are formed on the first end plate.

[0011] In one aspect of the energy storage device disclosed herein, as described above, a first fitting portion and a second fitting portion are formed at one end and the other end in the intersecting direction of the connecting portion, respectively. A first fitted portion that fits into the first fitting portion and a second fitted portion that fits into the second fitting portion are formed on the first end plate. Thus, by fitting the connecting portion into the end plate, the strap can be fixed to the end plate. Therefore, the strap can be fixed to the end plate without using rivets or the like. As a result, it is possible to suppress the increase in size of the energy storage device due to the structure of the portion connecting the end plate and the strap.

[0012] Invention Effects

[0013] According to this disclosure, it is possible to suppress the increase in the size of the energy storage device due to the construction of the portion connecting the end plate and the belt. Attached Figure Description

[0014] Figure 1 This is a schematic perspective view showing the structure of an energy storage device according to one embodiment.

[0015] Figure 2 This is a partially enlarged perspective view showing the structure near the contact plate in one embodiment.

[0016] Figure 3 It is along Figure 2 A cross-sectional view along line III-III.

[0017] Figure 4 It is along Figure 2 A cross-sectional view along line IV-IV.

[0018] Figure 5 This is a perspective view showing the structure of the end plate of a first modified embodiment.

[0019] Figure 6 This is a cross-sectional view showing the structure of the end plate and contact plate of a second modified embodiment. Detailed Implementation

[0020] Embodiments of this disclosure will be described with reference to the accompanying drawings. Furthermore, in the drawings referred to below, the same or equivalent parts are labeled with the same reference numerals.

[0021] Reference Figures 1-4 The energy storage device 100 in one embodiment of the present disclosure will be described. Figure 1This is a schematic exploded perspective view showing the structure of the energy storage device 100 according to this embodiment. The energy storage device 100 is, for example, installed in a hybrid electric vehicle, a plug-in hybrid electric vehicle, or a battery electric vehicle. Furthermore, the application of the energy storage device 100 is not limited to vehicle applications.

[0022] Furthermore, the X, Y, and Z directions in this specification are mutually orthogonal. For example, the X and Y directions can be the vehicle width direction and the front-rear direction, respectively, when the energy storage device 100 is mounted in the aforementioned vehicle. The X1 and X2 directions can also be the left and right sides of the vehicle, respectively. The Y1 and Y2 directions can also be the front and rear of the vehicle, respectively. Additionally, the Z direction can be a vertical direction. Furthermore, the X and Y directions are examples of the "arrangement direction" and "intersection direction" of this disclosure, respectively. Additionally, the Z direction is an example of the "thickness direction" of this disclosure.

[0023] The energy storage device 100 includes multiple energy storage units 10, end plates 20a and 20b, and a belt 30. Furthermore, end plates 20a and 20b have identical structures. It should be noted that... Figure 1 The simplified structure of end plates 20a and 20b is illustrated in the diagram. Furthermore, end plates 20a and 20b are examples of the "first end plate" and "second end plate" of this disclosure, respectively.

[0024] Multiple energy storage units 10 are arranged along the X direction. Each energy storage unit 10 includes a positive terminal 11 and a negative terminal 12. Adjacent energy storage units 10 in the X direction have their positive terminals 11 and negative terminals 12 electrically connected to each other via a busbar (not shown). Furthermore, in... Figure 1 The example described is that the positive terminal 11 and the negative terminal 12 are arranged on the upper surface 10a of the energy storage unit 10, but the arrangement of the positive terminal 11 and the negative terminal 12 is not limited to this example.

[0025] End plate 20a is disposed on the X1 side of the plurality of energy storage units 10. End plate 20b is disposed on the X2 side of the plurality of energy storage units 10. End plates 20a and 20b sandwich the plurality of energy storage units 10 in the X direction.

[0026] A belt 30 connects multiple energy storage units 10, end plates 20a and 20b. The belt 30 serves to suppress the expansion of each of the multiple energy storage units 10 in the X direction. Specifically, the belt 30 applies a load to the X2 side relative to the end plate 20a. The belt 30 applies a load to the X1 side relative to the end plate 20b. Thus, loads are applied to the multiple energy storage units 10 from both sides in the X direction via the end plates 20a and 20b.

[0027] The belt 30 includes a belt body 31 and a pair of contact plates 32. The pair of contact plates 32 have the same structure as each other. Furthermore, the contact plates 32 are an example of the "connecting part" of this disclosure.

[0028] The main body 31 extends along the plurality of energy storage units 10 in the X direction. The main body 31 is positioned on the Z1 side relative to the plurality of energy storage units 10 and the end plate 20a. The X1-side end 31a of the main body 31 is positioned above the end plate 20a. The X2-side end 31b of the main body 31 is positioned above the end plate 20b. The central portion 31c between the ends 31a and 31b of the main body 31 extends in the X direction above the plurality of energy storage units 10.

[0029] One side of the pair of contact plates 32 is connected to end 31a of the main body portion 31. The other side of the pair of contact plates 32 is connected to end 31b of the main body portion 31. Each of the pair of contact plates 32 is engaged with the lower surface 31d of the main body portion 31 (e.g., by welding or fusion). Alternatively, each of the pair of contact plates 32 can be connected to the lower surface 31d of the main body portion 31 by means of adhesive materials or bolts.

[0030] Figure 2 This is a partially enlarged view showing the contact plate 32 and end plate 20a on the X1 side. Furthermore, although not shown in the diagram, the contact plate 32 and end plate 20b on the X2 side are also... Figure 2 They are constructed in the same way. Additionally, in Figure 2 For simplicity, the illustration with the main body 31 has been omitted.

[0031] like Figure 2 As shown, the contact plate 32 is formed extending along the Y direction. Additionally, the contact plate 32 is formed extending along the X direction. That is, the contact plate 32 has a flat plate shape extending in the XY plane. Furthermore, the width W1 of the contact plate 32 in the Y direction is larger than the width W2 of the contact plate 32 in the X direction.

[0032] The end plate 20a includes a raised portion 21 that is raised upward (Z1 side). The contact plate 32 is disposed on the raised portion 21.

[0033] The raised portion 21 has an upper section 22 and a lower section 23. The contact plate 32 is disposed on the lower section 23. The upper section 22 is disposed above the lower section 23. The upper section 22 and the lower section 23 are continuously formed. The upper section 22 is disposed above the portion near the end of the lower section 23 on the X2 side (energy storage unit 10 side).

[0034] A pair of protrusions 24 are provided on the raised portion 21. The pair of protrusions 24 are arranged along the Y direction. Each of the pair of protrusions 24 is formed in a manner that extends in the vertical direction. Each of the pair of protrusions 24 protrudes upward from the lower section 23. Furthermore, each of the pair of protrusions 24 is integrally (continuously) formed with the lower section 23.

[0035] One of the pair of protrusions 24 is located at the Y1 side end of the lower section 23. The other of the pair of protrusions 24 is located at the Y2 side end of the lower section 23. The contact plate 32 is held by the pair of protrusions 24 in the Y direction.

[0036] Figure 3 It is along Figure 2 A cross-sectional view along line III-III. Figure 3 This is the cross-section when the contact plate 32 and end plate 20a are cut perpendicular to the X direction. Additionally, in... Figure 3 The diagram shows... Figure 2 The main body 31 is not shown in the figure.

[0037] In conventional energy storage devices, the device is fixed to the end plate using rivets or bolts. This requires space for mounting the rivets, resulting in a larger energy storage device.

[0038] Therefore, in this embodiment, the contact plate 32 is fixed to the end plate 20a by fitting into it. Furthermore, the relationship between the contact plate 32 and the end plate 20a is the same as the relationship between the contact plate 32 and the end plate 20b; therefore, the following description will focus specifically on the contact plate 32 and the end plate 20a.

[0039] Specifically, the contact plate 32 includes a protrusion 33 and a protrusion 34. The protrusion 33 is formed at the Y1 side end of the contact plate 32. The protrusion 34 is formed at the Y2 side end of the contact plate 32. Both the protrusion 33 and the protrusion 34 protrude outwards in the Y direction within the contact plate 32. The protrusions 33 and 34 have the same shape. Furthermore, the protrusion 33 is an example of the "first mating portion" and "first protrusion" of this disclosure. Additionally, the protrusion 34 is an example of the "second mating portion" and "second protrusion" of this disclosure.

[0040] A recess 25 is formed on end plate 20a to engage with protrusion 33. A recess 26 is formed on end plate 20a to engage with protrusion 34. Recesses 25 and 26 are each formed on the lower portion (lower end portion) of protrusion 24. Recesses 25 and 26 have the same shape. Furthermore, recess 25 is an example of the "first engaged portion" and "first recess" of this disclosure. Additionally, recess 26 is an example of the "second engaged portion" and "second recess" of this disclosure.

[0041] That is, the two ends (protrusions 33 and 34) of the contact plate 32 in the Y direction are engaged with the end plate 20a. Therefore, compared with the case where only one protrusion is provided to engage with the end plate 20a, the contact plate 32 can be more reliably prevented from falling off (detaching) from the end plate 20a.

[0042] The contact plate 32 includes an upper surface 35 and a lower surface 36. The upper surface 35 is the upper end face of the contact plate 32. The lower surface 36 is the lower end face of the contact plate 32. The upper surface 35 is welded (fused) to the lower surface 31d of the main body portion 31. The lower surface 36 is in contact with the end plate 20a (the upper surface 23a of the lower section portion 23).

[0043] The contact plate 32 includes a connecting surface 33a and a connecting surface 34a. The connecting surface 33a forms the side surface on the Y1 side of the contact plate 32. The connecting surface 34a forms the side surface on the Y2 side of the contact plate 32. The connecting surfaces 33a and 34a respectively connect the upper surface 35 and the lower surface 36. The connecting surface 33a is disposed on the protrusion 33. The connecting surface 34a is disposed on the protrusion 34.

[0044] The connecting surface 33a is inclined toward the Y1 side (outer side of the contact plate 32 in the Y direction) as it moves from the upper surface 35 toward the lower surface 36. The connecting surface 34a is inclined toward the Y2 side (outer side of the contact plate 32 in the Y direction) as it moves from the upper surface 35 toward the lower surface 36.

[0045] The connecting surfaces 33a and 34a are each provided such that they are covered from above by the protrusions 24. The protrusions 33 and 34 are each pressed from above (Z1 side) and from the side (Y1 side or Y2 side) by the protrusions 24. As a result, the contact plate 32 is prevented from falling off from the pair of protrusions 24 (recesses 25 and 26).

[0046] The protrusion 33 includes a corner portion 33b connecting the lower surface 36 to the connecting surface 33a. The corner portion 33b has a curved shape. The protrusion 34 includes a corner portion 34b connecting the lower surface 36 to the connecting surface 34a. The corner portion 34b has a curved shape. Furthermore, the portion of the recess 25 opposite to the corner portion 33b is curved along the corner portion 33b. The portion of the recess 26 opposite to the corner portion 34b is curved along the corner portion 34b. Additionally, a gap (clearance) may be formed between the corner portion 33b and the recess 25 (corner portion 34b and recess 26).

[0047] The protrusion 33 and the recess 25 extend along the X direction while interlocking with each other. The protrusion 34 and the recess 25 extend along the X direction while interlocking with each other. The interlocking portion of the protrusion 33 and the recess 25 (protrusion 34 and recess 26) extends in the X direction by the length L in the X direction of the area where the protrusion 24 and the contact plate 32 overlap in the Y direction. Figure 2 ).

[0048] Therefore, the contact plate 32 and the end plate 20a can be fixed within a relatively wide range. As a result, the contact plate 32 can be fixed more stably to the end plate 20a.

[0049] Figure 4 It is along Figure 2 A cross-sectional view along line IV-IV. Figure 4 It is the cross-section when the contact plate 32 and the end plate 20a are cut perpendicular to the Y direction.

[0050] The contact plate 32 includes a protrusion 37. The protrusion 37 is provided at the end of the plurality of energy storage cells 10 (X2 side) in the X direction of the contact plate 32. The protrusion 37 is formed protruding outward in the X direction of the contact plate 32.

[0051] A recess 27 is formed in the end plate 20a to engage with the protrusion 37. The recess 27 is formed in the step portion between the upper section 22 and the lower section 23 of the end plate 20a. Specifically, the recess 27 is formed in the space between the surface 22a of the lower section 23 side (X1 side, the side opposite to the energy storage unit 10) of the upper section 22 and the upper surface 23a of the lower section 23.

[0052] Therefore, apart from convex portion 33 and convex portion 34 ( Figure 3 In addition, the protrusion 37 also engages with the end plate 20a, thus enabling the contact plate 32 to be more stably fixed to the end plate 20a. Furthermore, since the protrusion 37 is provided at the end of the contact plate 32 on the side of the energy storage unit 10 (X2 side), the energy storage unit 10 can be easily subjected to a constraint load through the engagement of the protrusion 37 and the recess 27.

[0053] Additionally, protrusion 37 can also be combined with protrusion 33 and protrusion 34 respectively ( Figure 3) are formed continuously. Additionally, recess 27 can also be formed continuously with recess 25 and recess 26 respectively. Figure 3 It forms continuously.

[0054] The contact plate 32 includes a connecting surface 37a. The connecting surface 37a connects the upper surface 35 and the lower surface 36. The connecting surface 37a forms the side surface of the X2 side (energy storage unit 10 side) of the contact plate 32. The connecting surface 37a is provided on the protrusion 37. The connecting surface 37a is inclined toward the X2 side as it moves from the upper surface 35 toward the lower surface 36.

[0055] The connecting surface 37a is provided such that it is covered from above by the surface 22a of the end plate 20a. The protrusion 37 is pressed from above (Z1 side) and to the side (X2 side) by the upper section 22 (surface 22a). As a result, the protrusion 37 of the contact plate 32 is prevented from falling off the recess 27.

[0056] The protrusion 37 includes a corner portion 37b that connects the lower surface 36 to the connecting surface 37a. The corner portion 37b has a curved shape. The portion of the recess 27 opposite to the corner portion 37b is curved along the corner portion 37b. In addition, a gap (clearance) may be formed between the corner portion 37b and the recess 27.

[0057] The protrusion 37 and the recess 27 extend along the Y direction while interlocking with each other. In other words, the interlocking portion of the protrusion 37 and the recess 27 extends along the Y direction. As a result, the contact plate 32 and the end plate 20a can be fixed over a relatively wide range. Consequently, the contact plate 32 can be more stably fixed to the end plate 20a.

[0058] The contact plate 32 has a thickness t1 in the vertical direction (Z direction). The main body 31 has a thickness t2 in the vertical direction. Thickness t1 is greater than thickness t2. For example, thickness t1 may be more than three times the thickness t2.

[0059] Therefore, compared to cases where the thickness t1 is less than or equal to the thickness t2, the rigidity (e.g., bending rigidity) of the contact plate 32 can be improved. As a result, even when the contact plate 32 is engaged with the end plate 20a, deformation (breakage) of the contact plate 32 can be suppressed.

[0060] As described above, in this embodiment, the protrusion 33 of the contact plate 32 engages with the recess 25 of the end plate 20a, and the protrusion 34 of the contact plate 32 engages with the recess 26 of the end plate 20a. Therefore, the contact plate 32 can be fixed to the end plate 20a without using rivets, bolts, or the like. As a result, no space is needed for rivets, thus reducing the likelihood of the energy storage device 100 becoming too large. Furthermore, since rivets are not required, the number of components can be reduced, and the structure of the energy storage device 100 can be simplified. Additionally, compared to welding the contact plate 32 and the end plate 20a together, heat-affected zones on the contact plate 32, etc., can be suppressed.

[0061] [Variation Example]

[0062] In the above embodiment, an example is shown where each of the pair of protrusions 24 is formed in a vertically extending manner, but this disclosure is not limited thereto. The shape of the pair of protrusions may also be other than the shape described in the above embodiment.

[0063] For example, in Figure 5 In the example shown, the end plate 120 includes a pair of protrusions 124. Each of the protrusions 124 includes a vertical portion 124a extending upward from the lower section 23 and a horizontal portion 124b extending in the Y direction from the upper end of the vertical portion 124a. The horizontal portions 124b of each of the protrusions 124 extend toward each other in a direction of approach. Each of the protrusions 124 has an L-shape. Furthermore, in Figure 5 For simplicity, the diagram of the contact plate has been omitted.

[0064] Therefore, recesses 125 and 126 are formed in the region surrounded by the horizontal portion 124b, the vertical portion 124a, and the upper surface 23a of the lower segment 23. Recess 125 is formed by a protrusion 124 on the Y1 side. Recess 126 is formed by a protrusion 124 on the Y2 side. Furthermore, recess 125 is an example of the "first fitted portion" and "first recess" of this disclosure. Additionally, recess 126 is an example of the "second fitted portion" and "second recess" of this disclosure.

[0065] Furthermore, in the above embodiments, an example is shown where the contact plate 32 has a protrusion 37, but this disclosure is not limited thereto. For example, in Figure 6 In the example shown, the contact plate 132 has a protrusion 137. The protrusion 137 is provided to protrude from the lower end of the contact plate 132 toward the X2 side (the side of the energy storage unit 10). The protrusion 137 has a flat plate shape.

[0066] A recess 227 is formed in the end plate 220. The protrusion 137 of the contact plate 132 engages with the recess 227. The recess 227 is formed to be recessed from the surface 222a of the lower section 223 side (X1 side) of the upper section 222 of the end plate 220 toward the X2 side. The recess 227 is formed at the lower end of the upper section 222. In addition, the surface 222a may also extend orthogonally to the X direction.

[0067] In the above embodiments, examples are shown where end plates 20a and 20b are each fitted with contact plate 32, but this disclosure is not limited thereto. For example, end plate 20b may not be fitted with contact plate 32.

[0068] In the above embodiments, an example is shown where a protrusion (33, 34, 37) is formed in the contact plate 32 and a recess (25, 26, 27) is formed in the end plate 20a (20b), but this disclosure is not limited thereto. A recess may also be formed in the contact plate and a protrusion in the end plate.

[0069] In the above embodiment, an example is shown in which a protrusion 37 is formed only at the end of the contact plate 32 on the side of the energy storage unit 10 in the X direction, but this disclosure is not limited thereto. Alternatively, a protrusion may also be formed at the end of the contact plate on the opposite side of the energy storage unit 10 in the X direction.

[0070] In the above embodiments, an example is shown where the main body 31 and the contact plate 32 are separately disposed and joined (welded) together, but this disclosure is not limited thereto. The contact plate 32 may also be integrally formed with the main body 31.

[0071] In the above embodiments, an example is shown where a contact plate 32 with a flat plate shape is included in the belt 30, but the present disclosure is not limited thereto. Alternatively, a portion (a part of the belt) with a shape other than a flat plate shape (e.g., spherical and cubic) may be fitted with the end plate 20a (20b).

[0072] Furthermore, the structures of the above-described embodiments and their various modifications can also be combined with each other.

[0073] Furthermore, the embodiments disclosed herein should be considered illustrative in all respects and not restrictive. The scope of this disclosure is defined not by the description of the above embodiments but by the claims, and includes all modifications within the meaning and scope equivalent to the claims.

[0074] Explanation of reference numerals in the attached figures

[0075] 10. Energy storage unit, 20a. End plate (first end plate), 20b. End plate (second end plate), 25, 125. Recesses (first mating part) (first recess), 26, 126. Recesses (second mating part) (second recess), 27. Recess, 30. Belt, 31. Belt main body, 32. Contact plate (connecting part), 33. Protrusion (first mating part) (first protrusion), 34. Protrusion (second mating part) (second protrusion), 37. Protrusion, 100. Energy storage device, t1 thickness (thickness of connecting part), t2 thickness (thickness of belt main body).

Claims

1. An energy storage device, comprising: Multiple energy storage units are arranged in the same direction; The first end plate and the second end plate sandwich the plurality of energy storage units in the arrangement direction; as well as The belt connects the plurality of energy storage units, the first end plate, and the second end plate. The band includes: The main body extends along the arrangement direction of the plurality of energy storage units; as well as A connecting portion is provided at the end of the main body portion in the arrangement direction. The connecting portion is formed in a direction that intersects the arrangement direction. A first fitting portion and a second fitting portion are respectively formed at one end and the other end in the intersecting direction of the connecting portion. The first end plate has a first fitted portion that fits into the first fitted portion and a second fitted portion that fits into the second fitted portion.

2. The energy storage device according to claim 1, wherein, The connecting portion is formed in such a way that it extends in the arrangement direction. The first fitting portion and the first fitted portion are formed such that they fit together while extending in the arrangement direction. The second fitting portion and the second fitted portion are formed in such a way that they fit together while extending in the arrangement direction.

3. The energy storage device according to claim 1 or 2, wherein, The first fitting portion includes a first protrusion that protrudes outward in the intersecting direction. The second fitting portion includes a second protrusion that protrudes outward in the intersecting direction. The first fitted part includes a first recessed part fitted with the first convex part, The second fitted portion includes a second recessed portion fitted with the second convex portion.

4. The energy storage device according to claim 1 or 2, wherein, The ends of the plurality of energy storage cells in the connection portion along the arrangement direction are formed with protrusions that protrude outward in the arrangement direction. A recess is formed on the first end plate to engage with the protrusion.

5. The energy storage device according to claim 1 or 2, wherein, If the direction that intersects both the arrangement direction and the intersection direction is defined as the thickness direction, then the thickness of the connecting portion in the thickness direction is greater than the thickness of the main body portion in the thickness direction.

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