JP7654459B2 - Battery stack plate - Google Patents

Description

The present invention relates to a plate for a battery stack.

Various types of energy storage devices have been proposed in the past. For example, the energy storage device disclosed in Patent Document 1 includes a plurality of stacked energy storage modules and a plurality of plate-shaped members arranged between the energy storage modules.
The multiple energy storage modules and multiple plate-like members are arranged between a pair of insulating plates and restrained by restraining devices to form a laminate (battery stack) formed into a substantially rectangular parallelepiped shape.

The energy storage module has a resin frame, multiple battery cells, and multiple current collecting plates. The plate-shaped member has a conductive portion (conductive plate) that electrically connects adjacent energy storage modules, and an insulating portion (battery stack plate) arranged on the periphery. By positioning the insulating portion on the outer periphery of the energy storage device, the plate-shaped member can reduce the amount of exposure of the conductive portion from the outer periphery of the energy storage device.

JP 2020-198211 A

Incidentally, an energy storage device configured as described above may be electrically connected to a detection circuit to detect the voltage value, current value, etc., of the energy storage device. For example, the detection circuit is connected to a terminal provided on a plate-shaped member to detect the voltage value and current value of the energy storage device. In this way, terminals need to be provided on the plate-shaped member, and Patent Document 1 discloses that terminals are provided on insulating parts of the plate-shaped member. However, Patent Document 1 does not specifically disclose how the terminals are provided.

As a method for providing a terminal on the insulating portion of the plate-like member, for example, a recess capable of receiving the terminal may be provided on the insulating portion of the plate-like member, and the terminal may be received in the recess. However, simply placing the terminal in the recess may result in the terminal falling off the plate-like member.

One way to prevent the terminals from falling off is to provide the plate-shaped member with a locking structure that presses the terminals downward. However, as described above, the plate-shaped member may be sandwiched between multiple stacked energy storage modules, and there is a limit to the length of the plate-shaped member in the thickness direction, making it difficult to provide a locking structure.

As such, it was difficult to configure conventional power storage devices to prevent terminals from falling off.

The present invention was made in consideration of the above-mentioned circumstances, and its purpose is to provide a plate for a battery stack that prevents terminals from falling off.

In order to achieve the above-mentioned object, the plate for a battery stack according to the present invention is characterized by the following [1] to [4].
[1]
A plate for a battery stack comprising: a plate-shaped terminal to which an electric wire is connected; and a plate-shaped housing having an accommodating recess for accommodating the terminal,
The receiving recess is provided with a stop hole,
The terminal is
A connection portion electrically connected to a counterpart member;
a retaining piece that is inserted into the retaining hole and engaged with the retaining hole,
The retaining hole is provided with a wall portion located between the retaining piece and the connection portion.
It is a plate for battery stacks.
[2]
In the plate for a battery stack according to the above [1],
The terminal is
A first portion at an end of which the connection portion is provided;
a second portion connected to the first portion on the opposite side to the end portion and to which the electric wire is connected;
The first portion and the second portion have an L-shaped crossing shape.
It is a plate for battery stacks.
[3]
In the plate for a battery stack according to the above [2],
The retaining piece is provided at the second location so as to protrude toward the connection portion in an extension direction of the first location.
It is a plate for battery stacks.
[4]
In the plate for a battery stack according to any one of the above [1] to [3],
an insulating cover attached to the housing so as to cover the accommodating recess;
The insulating cover is
the connecting portion is configured to be movable between a provisionally locked state in which the connecting portion is covered with the accommodating recess and a fully locked state in which the accommodating recess is entirely covered with the connecting portion,
In the provisionally-retained state, the terminal is configured to cover at least a portion of the terminal.
It is a plate for battery stacks.

The battery stack plate of the configuration [1] above is described below. The terminals are connected to electric wires and to a mating member at the connection portion. The terminals are accommodated in the accommodating recesses so that the retaining pieces provided on the terminals are inserted into and engaged with the retaining holes provided in the accommodating recesses of the housing. As a result, the battery stack plate of this configuration can prevent the terminals from falling off without providing a member for preventing the terminals from falling off in the accommodating recesses.

Here, for example, when inserting the retaining piece into the retaining hole, if the retaining piece is inserted in contact with the retaining hole (particularly the inner surface of the hole), there is a risk of wear powder being generated due to sliding between the retaining piece and the retaining hole. If wear powder that may be generated when inserting the retaining piece into the retaining hole in this way adheres to the connection part or gets between the connection part and the mating member, it may hinder electrical conduction between the connection part and the mating member. Therefore, the battery stack plate of this configuration is provided with a wall portion located between the retaining piece and the connection part in the retaining hole. This suppresses the adhesion of wear powder to the connection part and the intrusion of wear powder between the connection part and the mating member, and therefore provides excellent reliability of electrical connection between the connection part and the mating member.

The battery stack plate of the configuration [2] above will be described below. The terminal has a first location where a connection part is provided at an end, and a second location that is continuous with the first location on the opposite side to the end where the connection part is provided and where an electric wire is connected. The terminal has an L-shape due to the intersection of the first location and the second location. This allows the battery stack plate of this configuration to pull out an electric wire in a direction different from the direction in which the opposing member is located.

The battery stack plate having the configuration [3] above is described below. The retaining piece is provided at the second location so as to protrude toward the connection portion. This prevents the connection portion from floating up from the accommodating recess, and therefore provides a more reliable electrical connection between the connection portion and the mating member than when the retaining piece is not provided at the second location so as to protrude toward the connection portion.

The battery stack plate of the above configuration [4] is described below. The battery stack plate of this configuration further includes an insulating cover configured to be movable between a provisionally locked state that covers the accommodating recess so as to expose the connection portion, and a fully locked state that covers the entire accommodating recess. The insulating cover is configured to cover at least a portion of the terminal in the provisionally locked state. As a result, in the provisionally locked state, the insulating cover presses the terminal, preventing the terminal from falling off. In other words, the retaining piece and the retaining hole prevent the terminal from falling off the housing until the insulating cover is attached to the housing, and when the insulating cover is attached to the housing, the retaining piece and the retaining hole, as well as the insulating cover, more appropriately prevent the terminal from falling off the housing.

In this way, the present invention can provide a battery stack plate that prevents terminals from falling off.

The present invention has been briefly described above. The details of the present invention will be further clarified by reading the following detailed description of the invention with reference to the accompanying drawings.

FIG. 1 is an exploded perspective view of a main portion of a battery stack according to an embodiment of the present invention. FIG. 2 is a perspective view of the battery stack plate shown in FIG. 1 with an insulating cover in a provisionally locked state. FIG. 3 is an exploded perspective view of a main part of the battery stack plate shown in FIG. FIG. 4 is a cross-sectional view showing a state in which the retaining piece of the connection terminal is inserted into the retaining hole of the housing and the connection terminal is accommodated in the housing. FIG. 5 is a top view of the embodiment shown in FIG. FIG. 6 is a cross-sectional view corresponding to FIG. FIG. 7 is a top view of the embodiment shown in FIG.

<Embodiment>
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is an exploded perspective view of a main portion of a battery stack 1 according to an embodiment of the present invention.

For the sake of convenience, the following definitions are used for the "front-rear direction," "up-down direction," "width direction," "front," "rear," "top," and "bottom" as shown in Figs. 1 to 7. The "front-rear direction," "width direction," and "up-down direction" are mutually perpendicular. The front-rear direction coincides with the extension direction of the housing 51 and the direction in which the electric wires 85 are drawn out. The up-down direction coincides with the plate thickness direction of the housing 51 and the connection terminal 80. The width direction coincides with the fitting direction between the side edges of the conductive plate 40 and the fitting grooves of the battery stack plates 50, 60, and 70. The direction in which the battery stack plate 50 is brought close to the side edges of the conductive plate 40 is called the "fitting direction." In other words, the fitting direction is also the insertion direction in which the retaining pieces 84 of the connection terminal 80 are inserted into the retaining holes 54 of the housing 51.

As shown in FIG. 1, the battery stack 1 according to this embodiment includes a plurality of stacked energy storage modules 10 (four in this example) and a plurality of plate-like members 20, 30 arranged between the plurality of energy storage modules 10. The battery stack 1 is arranged between a pair of insulating plates (not shown) and is configured into a substantially rectangular parallelepiped shape by restraining devices (not shown).

The energy storage module 10 is configured, for example, in the shape of a rectangular plate having multiple battery cells, multiple current collector plates, and a resin frame. The battery cells are configured with a positive electrode composite layer formed from nickel hydroxide or the like, a negative electrode composite layer formed from a hydrogen-absorbing alloy or the like, a separator formed from a porous film formed from a polyolefin resin, and an electrolyte.

The energy storage module 10 can also be constructed from a single battery cell, and the configuration of the battery cell is not limited to the above configuration and can adopt various known battery configurations.

As shown in FIG. 1, the plate-shaped member 20 of this embodiment is configured as a rectangular flat plate including a conductive plate 40 and a battery stack plate 50 and a battery stack plate 60 that are fitted to both side edges of the conductive plate 40.

In this embodiment, the plate-like member 30 is configured as a rectangular flat plate having a conductive plate 40 and a battery stack plate 50 and a battery stack plate 70 that are fitted to both side edges of the conductive plate 40.

The conductive plate 40 is formed in a long, narrow rectangular shape from a metal such as aluminum alloy or copper, and both longitudinal edge portions are thin and convex (not shown). Both longitudinal edge portions of the conductive plate 40 are fitted into the fitting groove 56 of the battery stack plate 50 and the fitting grooves (not shown) of the battery stack plates 60 and 70, respectively.

The conductive plate 40 is a conductive part that electrically connects adjacent energy storage modules 10 and also serves as a heat sink that cools adjacent energy storage modules 10.

Figure 2 is a perspective view showing the battery stack plate 50 in a provisionally locked state. Figure 3 is an exploded perspective view of the main parts of the battery stack plate 50.

As shown in Figures 2 and 3, the battery stack plate 50 of this embodiment includes a housing 51 that is a rectangular plate elongated in the front-rear direction, a connection terminal 80 accommodated in the housing 51, an electric wire 85 that is connected to the front terminal of the connection terminal 80, and an insulating cover 52.

As shown in FIG. 3, the housing 51 according to this embodiment has an accommodating recess 53 recessed downward from the upper plate surface. The accommodating recess 53 has a terminal accommodating recess 53a in which the connection terminal 80 is accommodated, and an electric wire accommodating recess 53b in which the electric wire 85 is accommodated.

The terminal accommodating recess 53a has a shape that corresponds to the outer peripheral shape of the connection terminal 80. The terminal accommodating recess 53a is provided with a retaining hole 54 into which the retaining piece 84 of the connection terminal 80 is inserted. Specifically, the retaining hole 54 is recessed from the wall portion on the tip side of the terminal accommodating recess 53a in the mating direction toward the tip side in the mating direction.

The terminal accommodating recess 53a has an inclined surface 55 that is inclined from the base end side in the mating direction toward the tip end side in the mating direction (i.e., along the insertion direction) so that the plate thickness of the housing 51 decreases. In other words, the inclined surface 55 is inclined downward from the base end side in the mating direction toward the tip end side in the mating direction. The inclined surface 55 is provided near the opening of the retaining hole 54 (see FIG. 4). Specifically, the inclined surface 55 is provided so as to be positioned inside the retaining hole 54.

The retaining hole 54 has a wall portion 58 extending in the width direction between the retaining piece 84 and the connection portion 83. In other words, the wall portion 58 is one of the walls that define the retaining hole 54 (see FIG. 6). As shown in FIG. 6, the end edge of the wall portion 58 on the tip side in the mating direction is located closer to the tip side in the mating direction than the end edge of the retaining piece 84 on the tip side in the mating direction. The end of the wall portion 58 on the base side in the mating direction defines the opening of the retaining hole 54 together with the housing 51.

The terminal accommodating recess 53a has a notch 57 cut out along the width direction at a portion corresponding to the connection portion 83 of the connection terminal 80. The notch 57 is located on the same side in the width direction as the fitting groove 56. In other words, the notch 57 is provided on the tip side facing the fitting direction.

As shown in FIG. 3, the connection terminal 80 according to this embodiment is configured in a generally L-shape with a first portion 81 extending in the width direction and a second portion 82 extending in the front-rear direction and continuing to the first portion 81.

The connection terminal 80 has a connection portion 83 electrically connected to the conductive plate 40 at the leading end side of the first portion 81 in the mating direction. Since the notch 57 is located below the connection portion 83 in the terminal accommodating recess 53a, when the connection terminal 80 is accommodated in the terminal accommodating recess 53a, the connection portion 83 is exposed downward.

When the side edge of the conductive plate 40 is fitted into the fitting groove 56 of the battery stack plate 50, the side edge of the conductive plate 40 enters the notch 57. In other words, the side edge of the conductive plate 40 enters below the connection portion 83, so that the connection portion 83 and the side edge of the conductive plate 40 come into contact, electrically connecting the conductive plate 40 and the battery stack plate 50. In this embodiment, the conductive plate 40 corresponds to the mating member.

The connection terminal 80 has a retaining piece 84 at the second location 82. The retaining piece 84 is provided at a position corresponding to the retaining hole 54 and is provided so as to protrude from the side edge of the second location 82 on the leading end side in the mating direction toward the leading end side in the mating direction. In the battery stack plate 50, the retaining piece 84 is inserted into the retaining hole 54 to prevent the connection terminal 80 from falling off the housing 51.

An electric wire 85 is connected to the front end of the second location 82. In this embodiment, the electric wire 85 is housed in the electric wire housing recess 53b and is pulled out from the front of the housing 51 in the front-rear direction (see FIG. 1). The electric wire 85 is connected to, for example, a voltage detection circuit at the other end opposite the end connected to the second location 82. This allows the voltage value, etc. of the battery stack 1 to be detected.

Figure 4 is a cross-sectional view showing a state in which the retaining piece 84 of the connection terminal 80 is inserted into the retaining hole 54 of the housing 51 and the connection terminal 80 is accommodated in the housing 51. Figure 5 is a view from above of the state shown in Figure 4. Figure 6 is a cross-sectional view corresponding to Figure 5.

When the connection terminal 80 is accommodated in the terminal accommodating recess 53a, the retaining piece 84 is inserted into the retaining hole 54 from the base end side in the mating direction toward the tip end side in the mating direction (from the right side of the paper to the left side of the paper in the width direction of FIG. 4). For example, the retaining piece 84 is inserted into the retaining hole 54 in a state in which the connection terminal 80 is tilted so that the retaining piece 84 is positioned below the side edge of the base end side in the mating direction of the second location 82.

When the retaining piece 84 is completely inserted into the retaining hole 54 and the connection terminal 80 is accommodated in the terminal accommodating recess 53a, the retaining piece 84 and the retaining hole 54 are engaged, as shown in Figures 4 and 5. Specifically, as shown in Figure 4 in particular, the upper plate surface 84a of the connection terminal 80 and the inner hole surface 54a of the upper wall portion of the retaining hole 54 are adjacent in the vertical direction. This restricts the upward displacement of the connection terminal 80. In other words, the connection terminal 80 is prevented from falling out of the housing 51.

When the retaining piece 84 is inserted into the retaining hole 54, it may be inserted in a state where it is in contact with the retaining hole 54 (particularly the inner surface 54a of the hole). At this time, there is a risk of wear powder being generated due to sliding between the retaining piece and the retaining hole. For example, if wear powder is generated, and it adheres to the connection portion 83 or gets between the connection portion 83 and the side edge portion of the conductive plate 40, it may hinder the electrical continuity between the connection terminal 80 and the conductive plate 40.

Therefore, in the battery stack plate 50 of this embodiment, a wall portion 58 is provided so as to be located between the retaining piece 84 and the connection portion 83. This prevents wear powder from adhering to the connection portion 83 and from entering between the connection portion 83 and the conductive plate 40.

Figure 7 shows the battery stack plate 50 from above when the insulating cover 52 is in a provisionally locked state.

When the connection terminal 80 and the electric wire 85 are accommodated in the accommodation recess 53, the insulating cover 52 is attached to the housing 51. The insulating cover 52 is configured to be movable between a provisionally locked state (see Figures 2 and 7) in which it covers the accommodation recess 53 so as to expose the connection portion 83, and a fully locked state in which it covers the entire accommodation recess 53.

As shown in Figures 2 and 7, when the connection terminal 80 and the electric wire 85 are accommodated in the accommodation recess 53, the insulating cover 52 is attached to the housing 51 in a provisionally locked state. In the provisionally locked state of the insulating cover 52, at least a portion of the first portion 81 and the second portion 82, excluding the connection portion 83, is covered. In other words, the insulating cover 52 presses down on the above-mentioned portions of the connection terminal 80 in the provisionally locked state. This further restricts the upward displacement of the connection terminal 80. In other words, the connection terminal 80 is more appropriately prevented from falling off the housing 51.

<Action and Effects>
According to the battery stack plate 50 of this embodiment, the retaining piece 84 of the connection terminal 80 is inserted into the retaining hole 54 provided in the terminal accommodating recess 53a of the housing 51, thereby engaging the retaining piece 84 with the retaining hole 54. As a result, the connection terminal 80 accommodated in the terminal accommodating recess 53a is prevented from falling off from the housing 51.

Furthermore, according to the battery stack plate 50 of this embodiment, the removal prevention hole 54 is provided with a wall portion 58 located between the removal prevention piece 84 and the connection portion 83, which suppresses adhesion of wear powder to the connection portion 83 that may occur when the removal prevention piece 84 is inserted into the removal prevention hole 54, and suppresses the intrusion of wear powder between the connection portion 83 and the conductive plate 40. As a result, the battery stack plate 50 of this embodiment has excellent reliability of the electrical connection between the connection portion 83 and the conductive plate 40.

Furthermore, according to the battery stack plate 50 of this embodiment, the terminal accommodating recess 53a has an inclined surface 55 near the opening of the retaining hole 54 (inside the hole in this example), so that when the connection terminal 80 is accommodated in the terminal accommodating recess 53a, the retaining piece 84 can be easily inserted into the retaining hole 54 by inserting the retaining piece 84 into the retaining hole 54 while aiming at the inclined surface 55. For example, when the insertion angle of the retaining piece 84 relative to the retaining hole 54 is equal to or greater than the inclination angle of the inclined surface 55 (and is equal to or less than 90 degrees), the retaining piece 84 is guided by the inclined surface 55 and inserted into the retaining hole 54.

If the terminal accommodating recess 53a did not have an inclined surface 55 near the opening of the retaining hole 54, there would be a risk of interference between the plate surface of the terminal accommodating recess 53a and the retaining piece 84 when the retaining piece 84 is inserted into the retaining hole 54, and the retaining piece 84 would not be easily inserted into the retaining hole 54. However, in the configuration of this embodiment, the terminal accommodating recess 53a has an inclined surface, so that the retaining piece 84 is easily inserted into the retaining hole 54, as described above.

Furthermore, according to the battery stack plate 50 of this embodiment, the connection terminal 80 has an L-shape due to the intersection of the first location 81 and the second location 82, so that the electric wire 85 can be pulled out in a direction different from the direction in which the conductive plate 40 is located.

Furthermore, according to the battery stack plate 50 of this embodiment, the retaining piece 84 is provided at the second location 82 so as to protrude toward the tip end in the mating direction, so that the connection portion 83 is prevented from floating up from the terminal accommodating recess 53a. This results in a more reliable electrical connection between the connection portion 83 and the conductive plate 40 than when the retaining piece 84 is not provided at the second location 82 so as to protrude toward the tip end in the mating direction.

In addition, since the retaining piece 84 is positioned so as to be aligned in the front-to-rear direction with the first location 81 including the connection portion 83, by providing a wall portion 58 between the retaining piece 84 and the connection portion 83 in the front-to-rear direction, it is possible to easily prevent wear powder from adhering to the connection portion 83 and from entering between the connection portion 83 and the conductive plate 40.

Furthermore, the battery stack plate 50 of this embodiment is movable between a provisionally locked state and a fully locked state, and is provided with an insulating cover 52 that covers at least a portion of the connection terminal 80 in the provisionally locked state, so that the insulating cover 52 presses down on the connection terminal 80 in the provisionally locked state. As a result, the connection terminal 80 is prevented from falling off the housing 51 by the retaining piece 84 and the retaining hole 54 until the insulating cover 52 is attached to the housing 51, and once the insulating cover 52 is attached to the housing 51, the retaining piece 84, the retaining hole 54, and the insulating cover 52 more appropriately prevent the connection terminal 80 from falling off the housing 51.

Furthermore, according to the battery stack plate 50 of this embodiment, by providing the housing 51 with the retaining hole 54 and the connection terminal 80 with the retaining piece 84, it is not necessary to provide the housing 51 with a locking structure or the like to prevent the connection terminal 80 from falling off, so that the battery stack plate 50 can be made low-profile, which in turn allows the battery stack 1 to be made smaller.

<Other forms>
The present invention is not limited to the above-described embodiment, and can be appropriately modified, improved, etc. In addition, the material, shape, size, number, arrangement location, etc. of each component in the above-described embodiment are arbitrary as long as the present invention can be achieved, and are not limited.

Here, the features of the embodiments of the battery stack plate according to the present invention described above will be briefly summarized and listed in the following [1] to [4].
[1]
A plate (50) for a battery stack, comprising: a plate-shaped terminal (connection terminal 80) to which an electric wire (85) is connected; and a plate-shaped housing (51) having an accommodation recess (53) for accommodating the terminal,
The receiving recess (53) is provided with a retaining hole (54),
The terminal (connection terminal 80) is
A connection portion (83) electrically connected to a counterpart member (conductive plate 40);
a retaining piece (84) that is inserted into the retaining hole (54) and engaged with the retaining hole,
The retaining hole (54) is provided with a wall portion (58) located between the retaining piece (84) and the connection portion (83).
Plate for battery stack (50).
[2]
In the battery stack plate (50) according to the above [1],
The terminal (connection terminal 80) is
A first portion (81) at an end of which the connection portion is provided;
a second portion (82) that is continuous with the first portion (81) on the opposite side to the end portion and to which the electric wire (85) is connected;
The first portion (81) and the second portion (82) have an L-shaped crossing shape.
Plate for battery stack (50).
[3]
In the plate for a battery stack (50) according to the above [2],
The retaining piece (84) is provided at the second location (82) so as to protrude toward the connection portion (83) in the extension direction of the first location.
Plate for battery stack (50).
[4]
In the plate for a battery stack (50) according to any one of the above [1] to [3],
The electric vehicle further includes an insulating cover (52) attached to the housing (51) so as to cover the receiving recess (53),
The insulating cover (52) is
The housing recess (53) is configured to be movable between a provisionally locked state in which the housing recess (53) is covered so as to expose the connection portion (83) and a fully locked state in which the housing recess (53) is covered in its entirety,
In the provisionally locked state, the terminal (connection terminal 80) is configured to cover at least a portion of the terminal.
Plate for battery stack (50).

REFERENCE SIGNS LIST 1 Battery stack 10 Electric storage module 20, 30 Plate-like member 40 Conductive plate 50 Battery stack plate 51 Housing 52 Insulating cover 53 Accommodating recess 53a Terminal accommodating recess 53b Electric wire accommodating recess 54 Retaining hole 54a Hole inner surface 55 Inclined surface 56 Fitting groove 57 Notch 58 Wall 60, 70 Battery stack plate 80 Connection terminal 81 First location 82 Second location 83 Connection portion 84 Retaining piece 84a Upper plate surface 85 Electric wire

Claims (4)

A plate for a battery stack comprising: a plate-shaped terminal to which an electric wire is connected; and a plate-shaped housing having an accommodating recess for accommodating the terminal,
The receiving recess is provided with a stop hole,
The terminal is
A connection portion electrically connected to a counterpart member;
a retaining piece that is inserted into the retaining hole and engaged with the retaining hole,
The retaining hole is provided with a wall portion located between the retaining piece and the connection portion.
Plate for battery stack. The plate for a battery stack according to claim 1 ,
The terminal is
A first portion at an end of which the connection portion is provided;
a second portion connected to the first portion on the opposite side to the end portion and to which the electric wire is connected;
The first portion and the second portion have an L-shaped crossing shape.
Plate for battery stack. The plate for a battery stack according to claim 2,
The retaining piece is provided at the second location so as to protrude toward the connection portion in an extension direction of the first location.
Plate for battery stack. The plate for a battery stack according to any one of claims 1 to 3,
an insulating cover attached to the housing so as to cover the accommodating recess;
The insulating cover is
the connecting portion is configured to be movable between a provisionally locked state in which the connecting portion is covered with the accommodating recess and a fully locked state in which the accommodating recess is entirely covered with the connecting portion,
In the provisionally-retained state, the terminal is configured to cover at least a portion of the terminal.
Plate for battery stack.

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