Patent Application
20200044210
Embodiment of the present invention relate to a battery pack.
Conventionally, battery packs are known which include metal-case battery cells including electrodes on the top walls, and holders for supporting the battery cells.
Patent Literature 1: WO 2013/073046
It is preferable to provide such a battery back with a novel configuration and less inconvenience, for example.
A battery pack of an embodiment includes a plurality of battery cells, a pipe, a bar, and an insulating plate, for example. The battery cells are aligned in a first direction and are each provided with an opening. The pipe is hollow and inserted into each opening in the first direction. The bar is inserted into a hollow of the pipe. The insulating plate is provided between opposing faces of the battery cells.
The following discloses exemplary embodiments of the present invention. The configurations of the embodiments and actions and results (effects) brought about by the configurations described below are merely exemplary. The present invention can also be achieved by configurations other than those disclosed in the owing embodiments. The present invention can attain at least one of various effects (including derivative effects) obtained by the configurations.
The following describes the embodiments with reference to the accompanying drawings. The following embodiments include similar or same elements. Thus, in the following, similar or same elements are denoted by common reference numerals, and overlapping descriptions are omitted. In the present specification, ordinals are used for distinguishing parts and members alone and are not intended to indicate order or priority.
The battery cell 2 includes a lithium-ion secondary battery, for example. The battery cell 2 may be another secondary battery such as a nickel-hydrogen battery or a nickel-cadmium battery. The lithium-ion secondary battery is a kind of nonaqueous electrolyte secondary battery, in which lithium ions in an electrolyte work for electric conduction. Examples of a positive electrode material include lithium-manganese composite oxides, lithium-nickel composite oxides, lithium-cobalt composite oxides, lithium-nickel-cobalt composite oxides, lithium-manganese-cobalt composite oxides, spinel lithium-manganese-nickel composite oxides, and lithium phosphates having an olivine structure; examples of a negative electrode material include oxide materials such as lithium titanate (LTO) and oxide materials such as niobium composite oxides. Examples of the electrolyte (an electrolytic solution, for example) include sole or combination of organic solvents mixed with lithium salt such as fluorine complex salts (LiBF4 or LiPF6, for example), such as ethylene carbonate, propylene carbonate, diethyl carbonate, ethylmethyl carbonate, and dimethyl carbonate. The battery cell 2 is also referred to as a cell, for example.
As illustrated in
The walls 20a to 20d are located at the periphery of the wall 20e and extend between the wall 20e and the wall 20f. The wall 20a and the wall 20c extend in a direction orthogonal to the direction (XY plane) and are spaced apart from each other in parallel in the Z direction. The walls 20a and 20c are referred to as side walls or peripheral walls and form two long sides of the four sides of the casing 20. One of the walls 20a and 20c is provided with a valve 20g for gas venting. The valve 20g is opened to reduce the pressure within the casing 20 when exceeding a threshold. The valve 20g is provided at about the center of the wall 20c in the Y direction, for example. The walls 20a and 20c are an example of a second wall.
The wall 20b and the wall 20d extend in a direction orthogonal to the Y direction (XZ plane) and are spaced apart from each other in the Y direction. The walls 20b and 20d are referred to as side walls or peripheral walls and form two short sides of the four sides of the casing 20. One of the walls 20b and 20d is provided with the positive electrode 25A, and the other is provided with the negative electrode 25B. The walls 20b and 20d are an example of a first wall.
At the four corners of the casing 20, four attachment tabs 20f1 protrude from the wall 20f. The attachment tabs 20f1 are provided with openings 20r as mounting holes. The openings 20r pass through the respective attachment tabs 20f1 in the X direction. The openings 20r are also referred to as through bores or through holes. The attachment tabs 20f1 are not limited to this example and may be provided only at two of the four corners of the casing 20 on one Y-directional side or only at two diagonal corners of the four corners of the casing 20, for example.
As illustrated in
The insulating plates 30 have a rectangular shape extending in the direction orthogonal to the X direction (YZ plane). The size of the insulating plates 30 is substantially the same as the size of the walls 20e and 20f. The insulating plates 30 are provided with openings 30r as mounting holes at the four corners corresponding to the openings 20r. The openings 30r pass through the insulating plates 30 in the X direction.
The insulating plates 30 include first plates 30A and second plates 30B, for example. The first plates 30A are each located between two adjacent battery cells 2 in the X direction. The second plates 30B are located at both X-directional ends of the battery cells 2, placing the battery cells 2 in-between them. The insulating plates 30 and the battery cells 2 are alternately stacked in the X direction. The first plates 30A are also referred to as intermediate plates, and the second plates 30B are also referred to as end plates.
The pipes 40 are of a hollow form extending in the X direction. The our pipes 40 are inserted into the respective openings 20r of the battery cells 2 aligned in the X direction. The pipes 40 each lie between an inner circumference 20r1 of the opening 20r and the shaft of the bolt 50 within the opening 20r of each of the battery cells 2. The pipes 40 are formed of an insulating material such as a synthetic resin material or rubber, for example.
The spacers 70 are provided at positions corresponding to the attachment tabs 20f1 of the battery cells 2. The spacers 70 are each placed between two adjacent attachment tabs 20f1 in the X direction, specifically, between the attachment tab 20f1 and the insulating plate 30. The spacers 70 are provided with respective openings 70a into which the pipes 40 are inserted. The openings 70a pass through the spacers 70 in the X direction. The spacers 70 are formed of an insulating material such as a synthetic resin material or rubber, for example.
The bolts 50 are inserted into the pipes 40, that is, hollows 40a. The bolts 50 and the flange nuts 60 correspond to every four pipes 40 (openings 20r). The second plates 303, the spacers 70, the battery cells 2, and the first plates 30A are tightly held between the heads of the bolts 50 and the flange nuts 60, and integrated (joined) together in the X direction as the battery pack 1. The bolts 50 and the flange nuts 60 are examples of fastening member.
In the present embodiment, a height h1 of the spacers 70 is set to smaller than a thickness (height) h2 of the battery cells 2 in the X direction, specifically, the space between the attachment tab 20f1 and the insulating date 30. Further, the length of the pipes 40 is set to smaller than the sum of the thicknesses of the battery cells 2 and the insulating plates 30 in the X direction. Consequently, according to the present embodiment, in fixing the battery cells 2 with the bolts 50 and the flange nuts 60, for example, the casings 20 of the battery cells 2 can be compressed in the X direction. This can restrict electrodes (not illustrated) inside the casings 20 from swelling in the X direction from the initial state and prevent degradation in the performance of the battery cells 2 due to swollen electrodes, for example. In the present embodiment, the casings 20 are formed of stainless steel (SUS) with a relatively small thickness, whereby the casings 20 can be more elastically deformable than metal-case battery cells 2, for example, placing the battery cells 2 in compressed state in the X direction relatively easily.
As described above, in the present embodiment, the battery pack 1 includes the battery cells 2 aligned in the X direction and each provided with the openings 20r; the hollow pipes 40 inserted into the openings 20r in the X direction, the bolts 50 inserted into the hollows 40a of the pipes 40, and the insulating plates 30 placed between the outer faces 20i of the walls 20e and 20f of the battery cells 2, for example. With such a configuration, the pipes 40 and the bolts 50 can work to inhibit the battery cells 2 from being displaced at least along the YZ plane, for example. In addition, with the flange nuts 60 provided at one X-directional end of the bolts 50 to engage with the bolts 50, the battery cells 2 can be integrated (joined) together in the X direction.
In the present embodiment, the pipes 40 have insulating properties, for example. With such a configuration, the battery cells 2 can be inhibited from electrically connecting to each other via the bolts 50 even when the bars such as the bolts 50 are formed of a metallic material, for example.
In the present embodiment, the battery cells 2 each include the wails 20b and 20d provided with the electrodes 25 and the wall 20c provided with the valve 20g for gas venting, for example. With such a configuration, the valve 20g is placed in the wall 20c different from the walls 20b and 20d provided with the electrodes 25, whereby the electrodes 25 and busbar 28 (refer to
In the present embodiment, the battery cells 2 are provided with the openings 20r with spacing in the Y direction or the Z direction, for example. With such a configuration, the openings 20r, and the pipes 40 and the bolts 50 inserted into the respective openings 20r can work to restrain the battery cells 2 from rotating along the YZ plane, for example. Thus, this can further inhibit the battery cells 2 from being mutually displaced along the YZ plane, for example.
A battery pack 1A of a modification illustrated in
However, the present modification is different from the first embodiment in that pipes 40A and bolts 50A are integrated with each other as illustrated in
A battery pack 1B of an embodiment illustrated in
However, the present embodiment is different from the first embodiment in additionally including restricting members 100 including a plurality of spacers 71 aligned in the X direction as illustrated in
As illustrated in
The protrusion 71b is provided on the top face 71a1 of the base 71a and protrudes upward, that is, in the X direction. As illustrated in
As illustrated in
The height h1 (refer to
As described above, in the present embodiment, the battery pack 1B includes the restricting members 100 that are inserted into the respective openings 20r in the X direction to abut on the inner circumferences 20r1 of the openings 20r and restrict the battery cells 2 from moving along the YZ plane. The restricting members 100 include the spacers 71 divided in the X direction, for example. With such a configuration, the spacers 71 of the restricting members 100 can work to inhibit the battery cells 2 from being displaced at least along the YZ plane, for example. In addition, the battery cells 2 can be integrated (joined) together in the X direction by the protrusions 30a and the caps 61 at the end of the restricting members 100.
In the present embodiment, the spacers 71 each include the base 71a interposed between the openings 20r of the battery cells 2, and the protrusion 71b that protrudes in the X direction (upward) from the base 71a and is inserted into at least one of the openings 20r. The base 71a is provided with the recesses 71c connectable to the protrusions 71b of an adjacent spacer 71 in the opposite X direction (downward), for example. With such a configuration, the spacers 71 can be integrated in the X direction more easily by fitting the protrusions 71b into the recesses 71c, for example.
A battery pack 1C of a modification illustrated in
However, the present modification is different from the second embodiment in that each spacer 72 is provided with a protrusion 72b having a male screw 72b1 and a recess 72c formed as a female screw 72c1 as illustrated in
The spacers 72 each include a base 72a and the protrusion 72b, for example. The protrusion 72b is provided on the bottom face of the base 72a and protrudes downward. The recess 72c is formed in the top face of the base 72a and is concaved downward. The spacers 72 are formed of an insulating material such as a synthetic resin material or rubber, for example.
The male screw 72b1 of the protrusion 72b is inserted into the recess 72c of an adjacent spacer 72 below and screwed into the female screw 72c1 through at least either the opening 20r of the attachment tab 20f1 or the opening 30r of the insulating plate 30 therebelow. Thereby, the spacers 72 are joined together in order in the X direction, to integrate (join) the battery cells 2 in the X direction. In the present embodiment, one (top) of the two second plates 30B is integrated with the spacer 72 in the X direction with bolts 62 each provided with a male screw to screw into the female screw 72c1 of the spacer 72. The other (bottom) is integrated with the spacer 72 in the X direction with nuts 63 each provided with a female screw to engage with the male screw 72b1 of the spacer 72.
As described above, in the present modification, the spacers 72 are integrated in the X direction by screwing the male screws 72b1 of the protrusions 72b into the female screws 72c1 in the recesses 72c, for example. With such a configuration, the battery cells 2 can be integrated more easily, more smoothly, or more firmly with the female screws 72c1 and the male screws 72b1 of the spacers 72. In addition, due to the spacers 72 having insulating properties, the battery cells 2 can be prevented from electrically connecting to each other via the spacers 72, for example.
A battery pack 15 of an embodiment illustrated in
However, the present embodiment is different from the first modification of the second embodiment in that the valve 20g for gas venting is provided on the wall 20e as illustrated in
In the present embodiment, the insulating plates 30 include the second plates 30B located on the top and the bottom, and third plates 30C interposed between the second plates 30B and the battery cells 2 and between the battery cells 2. The third plates 30C are each provided with a relief hole 30s for gas. The relief hole 30s can also be referred to as an exhaust passage.
The relief hole 30s includes a first hole 30s1 and a second hole 30s2, for example. The first hole 20s1 is an oblong hole (circular hole) and is aligned with the valve 20g in the X direction. The second hole 3 is slit-like and extends between the first hole 30s1 and one Z-directional end of the first plate 30A or the third plate 30C.
As described above, in the present embodiment, the valve 20g is provided in the wall 20e different from the walls 20b and 20d provided with the electrodes 25, and the insulating plate 30 is provided with the gas relief hole 30s, for example. With such a configuration, for example, gas, when released from the valve 20g, can be discharged to the location away from the electrodes 25 and the busbar 28 through the relief hole 30s.
A battery pack 1E of an embodiment illustrated in
However, the present embodiment is different from the first modification of the second embodiment in that the battery cells 2 include insulating rings 80 in the openings 20r (the attachment tabs 20f1) as illustrated in
As illustrated in
The flange 80b projects from one (upper) X-directional end of the insertion 80a to the YZ plane along the attachment tab 20f1. The flange 80b lies between the bottom of the base 72a and the attachment tab 20f1.
As described above, in the present embodiment, the battery pack 1E includes the insulating rings 80 each including the insertion 80a to be inserted into the opening 20r and located between the protrusion 72b and the inner circumference 20r1, for example. With such a configuration, the battery cells 2 can be inhibited from electrically connecting to each other via the spacers 72 even when at least part of the spacer 72 such as the protrusions 72b (the male screws 72b1) are formed from a metallic material, for example.
A battery pack 1F of a modification illustrated in
However, the present modification is different from the fourth embodiment in that the battery cells 2 include insulating clips 81 in the openings 20r (the attachment tabs 20f1) as illustrated in
As illustrated in
The insertion 81a protrudes from the inner edge of the opening 81c toward the opening 81d. The insertion 81a has a ring shape along the inner circumference 20r1 of the opening 20r and is inserted into the opening 20r. The insertion 81a is located between the inner circumference 20r1 and the protrusion 72b (the male screw 72b1) of the spacer 72. The insertion 81a can also be referred to as a protrusion, an interposition, a protector, or a contact preventer. The insertion 81a is an example of a first insertion. The insulating clips 81 of the present embodiment can attain effects substantially similar to those of the insulating rings 80 of the fourth embodiment.
A battery pack 1G of an embodiment illustrated in
However, the present embodiment is different from the fourth embodiment in that the insulating plates 30 are provided with protrusions 30e as illustrated in
The insulating plates 30 each include a plate 30d and the protrusions 30e, for example. The plate 30d has a rectangular shape extending in the direction orthogonal to the X direction (YZ plane). The plate 30d is located on the opposing faces of the battery cells 2, that is, between the outer faces 20i of the walls 20e and 20f. The plate 30d is also referred to as a base. The plate 30d is provided with openings 30r as mounting holes at the four corners.
As illustrated in
A battery pack 1H of an embodiment illustrated in
However, the present embodiment is different from the fourth embodiment in additionally including support members 90 as illustrated in
The support members 90 have a substantially U shape opening in the Y direction as viewed from the Z direction. The support members 90 each include two supports 90a and 90b at both X-directional ends and a connection 90c that connects the two supports 90a and 90b. One of the supports 90a and 90b supports one X-directional end of the battery cells 2, while the other supports the other X-directional end of the battery cells 2. In other words, the support members 90 hold the battery cells between the two supports 90a and 90b. The support members 90 can be formed of spring steel or stainless steel, for example. The support members 90 can support (integrate) the battery cells 2 and the insulating plates 30 while pressed to approach each other by force from the elastic deformation of the two supports 90a and 90b. According to the present embodiment, it is thus made possible to more firmly integrate the components including the battery cells and ensure the compressed state of the battery cells 2 in the X direction, for example. The two supports 90a and 90b are each provided with a recess 90d (refer to
As illustrated in
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions. The present invention can also be implemented by configurations other than those disclosed in the embodiments and can achieve various effects (including derivative effects) achieved by the basic configuration (technical features). The specifications (structure, type, direction, shape, size, length, width, thickness, height, number, arrangement, position, material, and the like) of the elements can be changed as appropriate.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2016-107901 | May 2016 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2017/020133 | 5/30/2017 | WO | 00 |
