Inter-stack connection structure and protector

Abstract

The present invention provides an inter-stack connection structure and protector that can reduce the possibility of damage to terminal fittings or short circuits when the connection terminals of battery stacks are not adjacent to each other. [Solution] The inter-stack connection structure electrically connects the connection terminals CT of a first battery stack BS1 with a second battery stack BS2 provided on a specific side of the first battery stack BS1, and comprises a first terminal T1 that can be electrically connected to the connection terminal CT of the first battery stack BS1, a second terminal T2 that can be electrically connected to the connection terminal CT of the second battery stack BS2, a hollow-shaped protector P, and an electric wire inserted into the protector P, with one end connected to the first terminal T1 and the other end connected to the second terminal T2. The protector P has a hinge portion that can be bent in a predetermined direction, and can transition between a first state for connecting the connection terminals CT and a second state by bending the first state in a predetermined direction using the hinge portion.

Description

Technical Field

[0001] The present invention relates to a stack connection structure and a protector.

Background Art

[0002] Conventionally, a stack connection structure for electrically connecting battery stacks in which a plurality of battery cells are stacked has been proposed (see, for example, Patent Documents 1 and 2). Among these, in the one described in Patent Document 1, the connection terminals of the battery stacks are in an adjacent relationship. Therefore, the connection terminals of the battery stacks are electrically connected by a bus bar. On the other hand, in the one described in Patent Document 2, the connection terminals of the battery stacks are not in an adjacent relationship and are provided at separated positions. In such a case, the connection terminals of the battery stacks are electrically connected by a flexible electric wire. Terminal fittings for connecting to the connection terminals are provided at both ends of the electric wire.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the stack connection structure described in Patent Document 2, since a flexible electric wire is used, there is a problem that the position of the electric wire is not stable between the time of connecting the electric wire to the connection terminal of the first battery stack and the time of connecting it to the connection terminal of the second battery stack. Therefore, when the electric wire is bent in an unexpected direction, there is a possibility that the terminal fitting may collide with other members, causing damage or deformation, and there is also a possibility of causing a short circuit.

[0005] The present invention was made to solve these conventional problems, and its objective is to provide an inter-stack connection structure and protector that can reduce the possibility of damage to terminal fittings or short circuits when the connection terminals of battery stacks are not adjacent to each other. [Means for solving the problem]

[0006] The inter-stack connection structure according to the present invention is an inter-stack connection structure for electrically connecting the connection terminals of a battery pack comprising first and second battery stacks, each having battery cells stacked and connection terminals on a specific direction side, with the second battery stack provided on the specific direction side of the first battery stack, comprising: a first terminal electrically connectable to the connection terminal of the first battery stack; a second terminal electrically connectable to the connection terminal of the second battery stack; a hollow-shaped protector; and an electric wire, one end of which is connected to the first terminal and the other end of which is connected to the second terminal, and which is inserted into the protector, wherein the protector has a hinge portion that can be bent in a predetermined direction, and is transitionable between a first state for connecting the connection terminals and a second state obtained by bending the first state in the predetermined direction using the hinge portion.

[0007] Furthermore, the protector according to the present invention is a hollow protector that houses wires connected to both a first terminal electrically connectable to the connection terminal of the first battery stack and a second terminal electrically connectable to the connection terminal of the second battery stack, which are first and second battery stacks having stacked battery cells and connection terminals on a specific direction side, and has a hinge portion that can be bent in a predetermined direction, and is transitionable between a first state for connecting the connection terminals and a second state in which the first state is bent in the predetermined direction by the hinge portion. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an inter-stack connection structure and protector that can reduce the possibility of damage to terminal fittings or short circuits when the connection terminals of battery stacks are not adjacent to each other. [Brief explanation of the drawing]

[0009] [Figure 1] This is a perspective view showing the inter-stack connection structure according to this embodiment. [Figure 2] Figure 1 is an exploded perspective view of a part of the configuration shown. [Figure 3] This is a diagram showing the first hinge section, where (a) shows the state before folding, (b) shows the state after folding, and (c) is an enlarged view of the first hinge section. [Figure 4] This is a diagram showing the second hinge section, where (a) shows the state after folding and (b) is an enlarged view of the second hinge section. [Figure 5] This is a perspective view showing the first step in the electrical connection method for a battery stack. [Figure 6] This is a top view showing the second step in the electrical connection method for the battery stack. [Modes for carrying out the invention]

[0010] The present invention will be described below in accordance with preferred embodiments. It should be noted that the present invention is not limited to the embodiments shown below, and can be modified as appropriate without departing from the spirit of the invention. Furthermore, in the embodiments shown below, some illustrations and descriptions of certain components are omitted. It goes without saying that, regarding the details of the omitted technologies, publicly known or well-known technologies are applied as appropriate, to the extent that they do not contradict the content described below.

[0011] Figure 1 is a perspective view showing the inter-stack connection structure according to this embodiment, and Figure 2 is an exploded perspective view of a part of the configuration shown in Figure 1. The inter-stack connection structure 1 shown in Figure 1 comprises a first battery stack BS1, a second battery stack BS2, a first terminal T1, a second terminal T2, a protector P, and an electric wire W (see Figure 2). The inter-stack connection structure 1 electrically connects the first and second battery stacks BS1 and BS2 in a battery pack BP comprising the first battery stack BS1 and the second battery stack BS2.

[0012] The first and second battery stacks BS1 and BS2 are constructed by stacking battery cells BC. Furthermore, the first and second battery stacks BS1 and BS2 are equipped with connection terminals (see symbol CT in Figure 6) on a specific direction side. Additionally, the second battery stack BS2 is located on the specific direction side of the first battery stack BS1. Therefore, the first and second battery stacks BS1 and BS2 are equipped with connection terminals CT in the same direction, and the connection terminals CT are not adjacent to each other. Note that the connection terminals CT do not need to be located on the end faces in a specific direction, as long as they are located on the specific direction side of the first and second battery stacks BS1 and BS2. For example, the first battery stack BS1 may have a connection terminal CT on its end face, while the second battery stack BS2 may be located near that end face on another side. Alternatively, both connection terminals CT may be located near the end faces on other sides of the first and second battery stacks BS1 and BS2.

[0013] As shown in Figure 2, the first and second terminals T1 and T2 are both terminal fittings made of metal plates. The first terminal T1 is electrically connectable to the connection terminal CT of the first battery stack BS1, and the second terminal T2 is electrically connectable to the connection terminal CT of the second battery stack BS2. The first and second terminals T1 and T2 have openings T11 and T21 at their ends for connection to the connection terminal CT. The first and second terminals T1 and T2 are electrically connected to the connection terminal CT through the openings T11 and T21 by bolting or the like. The base of the first terminal T1 is connected to one end of the electric wire W, and the base of the second terminal T2 is connected to the other end of the electric wire W.

[0014] The protector P is formed in a hollow shape and houses and protects the first and second terminals T1 and T2 and the electric wire W inside. In this embodiment, the electric wire W is assumed to be a flexible flat cable, but it is not limited to this and may be composed of multiple round wires or the like.

[0015] The protector P comprises a first component P1 and a second component P2. The first component P1 and the second component P2 are members configured to sandwich the electric wire W in the depth direction perpendicular to the longitudinal direction and the vertical direction. The first component P1 is a member with a U-shaped cross-section with the back side open in the depth direction, and the second component P2 is a member with a U-shaped cross-section with the front side open in the depth direction.

[0016] Furthermore, the first component P1 has an engaged portion P11 that extends inward at the position of the U-shaped end. The engaged portion P11 is made of a U-shaped plate. On the other hand, the second component P2 has an engaged portion P21 with an inclined structure near the U-shaped end. When the electric wire W is housed in these first and second components P1 and P2, the engaged portion P21 and the engaged portion P11 engage. As a result, the first and second components P1 and P2 cover and protect the electric wire W.

[0017] Furthermore, the protector P comprises a third component P3 and a fourth component P4. The third component P3 is a U-shaped cross-section member with an open bottom, and the fourth component P4 is a U-shaped cross-section member with an open top. The third and fourth components P3 and P4 have enlarged portions P31 and P41 with a larger inner cross-sectional area on one end, and reduced portions P32 and P42 with a smaller inner cross-sectional area than the enlarged portions P31 and P41 on the other end.

[0018] Further, the third component P3 has an engaged portion P33 formed by a U-shaped plate extending downward from the lower end of the reduced portion P32. On the other hand, the fourth component P4 has an engaging portion P43 with an inclined structure near the upper end of the reduced portion P42 having a U-shaped cross section. These third and fourth components P3 and P4 are engaged with each other with the engaging portion P43 and the engaged portion P33 in a state where the other ends of the first and second components P1 and P2 are accommodated by the enlarged portions P31 and P41 and the central portion of the electric wire W is accommodated by the reduced portions P32 and P42. As a result, the third and fourth components P3 and P4 are in a state of covering and protecting a part of the first and second components P1 and P2 and a part of the electric wire W.

[0019] Also, the protector P includes fifth to eighth components P5 to P8. The fifth component P5 is a member having a U-shaped cross section with the back side in the depth direction open, and the sixth component P6 is a member having a U-shaped cross section with the front side in the depth direction open. Note that a terminal hole P61 through which the tip of the first terminal T1 is inserted is formed on one end side of the sixth component P6.

[0020] Further, the fifth component P5 has an engaged portion P53 formed by an opening in the plate materials P52 constituting both ends of the U shape. On the other hand, the sixth component P6 has an engaging portion P63 with an inclined structure in the plate materials P62 constituting both ends of the U shape. These fifth and sixth components P5 and P6 are engaged with each other with the engaging portion P63 and the engaged portion P53 in a state where the electric wire W and the first terminal T1 are accommodated on one end side and the first and second components P1 and P2 are accommodated on the other end side. As a result, the fifth and sixth components P5 and P6 are in a state of covering and protecting the base side of the first terminal T1, one end side of the electric wire W, and one end side of the first and second components P1 and P2.

[0021] The seventh component P7 is a member having a U-shaped cross section with the back side in the depth direction open, and the eighth component P8 is a member having a U-shaped cross section with the front side in the depth direction open. Note that a terminal hole P81 through which the tip of the second terminal T2 is inserted is formed on the other end side of the eighth component P8.

[0022] Furthermore, the seventh component P7 has engaged portions P73 formed by openings in the plate material P72 that constitutes both ends of the U-shape. On the other hand, the eighth component P8 has engaged portions P83 with an inclined structure in the plate material P82 that constitutes both ends of the U-shape. With the seventh and eighth components P7 and P8 housing the electric wire W and the second terminal T2 at one end and the reduced portions P32 and P42 of the third and fourth components P3 and P4 at the other end, the engaged portion P83 and the engaged portion P73 engage. As a result, the seventh and eighth components P7 and P8 cover and protect the base side of the second terminal T2, the other end of the electric wire W, and the other end of the reduced portions P32 and P42.

[0023] Furthermore, in this embodiment, the protector P is equipped with first and second hinge portions (hinge portions) that can be bent in a predetermined direction. Figure 3 is a configuration diagram showing the first hinge portion, where (a) shows the state before bending, (b) shows the state after bending, and (c) is an enlarged view of the first hinge portion.

[0024] As shown in Figures 3(a) and 3(b), the protector P is fixed at one end by the first hinge H1, and the other end can be rotated and folded in the vertical direction (an example of a predetermined direction). In other words, the protector P can transition between the first state shown in Figure 3(a) and the second state shown in Figure 3(b). The first state is for electrically connecting the connection terminals CT. The second state is the state in which the protector P is folded vertically using the first hinge H1 from the first state.

[0025] To achieve this transformation, the protector P has the following configuration. Specifically, as shown in Figures 2 and 3(c), the first and second parts P1 and P2 have projections P12 and P22 at the upper corners of one end. Furthermore, the fifth and sixth parts P5 and P6 have openings P54 and P64 into which the projections P12 and P22 fit.

[0026] Here, the protrusions P12, P22 and the openings P54, P64 are aligned coaxially in the depth direction. Furthermore, the fifth and sixth parts P5 and P6 have restricting walls P55 and P65 on their lower sides, while the upper ends of the other sides are open. As a result, the other parts P1 to P4, P7, and P8 can be rotated and folded upward around the protrusions P12 and P22 relative to the fifth and sixth parts P5 and P6 (see Figure 3(b)).

[0027] Here, the first, second, fifth, and sixth parts P1, P2, P5, and P6 have a first fixing structure (fixing structure) F1. As shown in Figure 2, the first fixing structure F1 is composed of small protrusions P13 provided on the first and second parts P1 and P2, and small holes P56, P57, P66, P67, etc. provided on the fifth and sixth parts P5 and P6. As shown in Figure 3(c), the small protrusion P13 provided on the first part P1 is located slightly below the projection P12 and protrudes toward the front, similar to the projection P12. The first small hole P56 provided on the fifth part P5 is located slightly below the opening P54. As shown in Figure 3(c), the small protrusions P13 and the first small hole P56 are structured to fit together in the first state without bending. Furthermore, as shown in Figures 2 and 3(c), the second small hole P57 is located at a rotational position of the first small hole P56 centered on the opening P54. The small projection P13 and the second small hole P57 are structured to fit together in the second state. Therefore, the first fixing structure F1 can be fixed in both the first and second states by the small projection P13 fitting into either the first small hole P56 or the second small hole P57.

[0028] Although not shown in the diagram, the fourth component P4 also has small protrusions similar to those of the small protrusion P13. Furthermore, the sixth component P6 also has small holes P66 and P67. These are positioned symmetrically to the small protrusions P13 and holes P56 and P57 in the depth direction. Therefore, the small protrusions of the fourth component P4 and the small holes P66 and P67 of the sixth component P6 function similarly, and their positions can be fixed in both the first and second states.

[0029] Figure 4 is a diagram showing the configuration of the second hinge section, where (a) shows the state after folding and (b) is an enlarged view of the second hinge section. As shown in Figure 4(a), the protector P is fixed at one end by the second hinge section H2, and the other end can be rotated and folded in the depth direction (an example of a predetermined direction). In other words, the protector P can transition between the first state shown by the dashed line in Figure 4(a) and the second state shown by the solid line. The first state is the state for electrically connecting the connection terminals CT. The second state is the state in which the protector P is folded in the depth direction using the second hinge section H2 from the first state.

[0030] To achieve this transformation, the protector P has the following configuration. Specifically, as shown in Figures 2 and 4(b), the first component P1 has a projection P14 that protrudes upward from the upper surface on the far end. The third component P3 has an opening P34 in the enlarged portion P31 into which the projection P14 fits. Although not shown, the first component P1 also has a projection that protrudes downward from the lower surface on the far end. Furthermore, the fourth component P4 has an opening in the enlarged portion P31 into which this projection fits. The two projections P14 of the first component P1 and the openings P34 of the third and fourth components P3 and P4 are arranged coaxially. As a result, the third and fourth components P3 and P4 can be rotated and folded in the depth direction around the projection P14 relative to the first and second components P1 and P2 (see Figure 4(a)).

[0031] Here, the first to fourth parts P1 to P4 have a second fixing structure (fixing structure) F2. As shown in Figure 2, the second fixing structure F2 is composed of a small projection P23 provided on the second part P2 and small holes P35, P36, etc. provided on the third and fourth parts P3 and P4. The small projection P23 provided on the second part P2 protrudes upward from the upper surface on the far end. The first small hole P35 provided on the third part P3 is located slightly behind the opening P34. The small projection P23 and the first small hole P35 are structured to fit together in the first state without bending. Also, as shown in Figures 2 and 4(b), the second small hole P36 is located at the rotational position of the first small hole P35 around the opening P34. The small projection P23 and the second small hole P36 are structured to fit together in the second state. Therefore, the second fixing structure F2 can be fixed in position in both the first and second states by the small projection P23 fitting into the first small hole P35 or the second small hole P36.

[0032] Although not shown in the diagram, the lower surface of the second component P2 also has a small protrusion similar to the small protrusion P23. Furthermore, the fourth component P4 also has small holes similar to the small holes P35 and P36. These are positioned symmetrically to the small protrusion P23 and the small holes P35 and P36 in the vertical direction. Therefore, the small protrusion on the lower surface of the second component P2 and the small holes in the fourth component P4 function similarly, and their positions can be fixed in both the first and second states.

[0033] In addition, the third, fourth, seventh, and eighth parts P3, P4, P7, and P8 of the protector P according to this embodiment have an expandable and retractable structure TS, as shown in Figure 3(a). The expandable and retractable structure TS is composed of projections P37, P44 and sliding grooves P74, P75, P84, etc., as shown in Figures 2 and 3(a).

[0034] More specifically, the third component P3 has a projection P37 on its side near the upper end of the other end. Similarly, the fourth component P4 has a projection P44 on its side near the lower end of the other end. Furthermore, the seventh part P7 has a first slide groove P74 into which the projection P37 of the third part P3 fits. In addition, the seventh part P7 has a second slide groove P75 into which the projection P44 of the fourth part P4 fits. The first slide groove P74 is formed on the side surface near the upper end of one end of the seventh part P7, extending in the longitudinal direction. The second slide groove P75 is formed on the side surface near the lower end of one end of the seventh part P7, extending in the longitudinal direction. As a result, the projections P37 and P44 are movable within the slide grooves P74 and P75, and the seventh and eighth parts P7 and P8 are expandable and contractible relative to the third and fourth parts P3 and P4 by the length of the slide grooves P74 and P75.

[0035] Furthermore, although not shown in the illustration, the third and fourth parts P3 and P4 have projections similar to those of the projections P37 and P44. In addition, although not shown in the illustration, the eighth part P8 also has a slide groove P84 similar to the slide grooves P74 and P75. These projections and slide grooves P84 are formed in positions symmetrical in the depth direction to the projections P37 and P44 of the third and fourth parts P3 and P4, and to the slide grooves P74 and P75 of the seventh part P7. Therefore, the seventh and eighth parts P7 and P8 function similarly and are expandable and contractible relative to the third and fourth parts P3 and P4.

[0036] Furthermore, since the protector P is both bendable and stretchable, the electric wire W will be pulled when bent or extended. Therefore, to prevent the electric wire W from breaking under such tension, it is preferable that the electric wire W is folded and arranged within the protector P so as to have a bent portion.

[0037] Next, the electrical connection method for the battery stacks BS1 and BS2 according to this embodiment will be described. Figure 5 is a perspective view showing the first step of the electrical connection method for the battery stacks BS1 and BS2, and Figure 6 is a top view showing the second step of the electrical connection method for the battery stacks BS1 and BS2.

[0038] As shown in Figure 5, first, the first battery stack BS1 is mounted on the housing B that constitutes the battery pack BP. Next, a protector P containing the first terminal T1, the second terminal T2, and the wire W is prepared. Then, the first terminal T1 and the connection terminal CT of the first battery stack BS1 are connected by bolting or the like.

[0039] Next, as shown in Figure 6, the protector P is bent. Specifically, the protector P is bent upward by the first hinge H1 to reach a second state with respect to the first hinge H1. Furthermore, preferably, the protector P is bent forward by the second hinge H2 to reach a second state with respect to the second hinge H2. Then, the second battery stack BS2 is mounted.

[0040] Here, since the bending direction is limited by the hinges H1 and H2, the protector P is prevented from bending in an unexpected direction. Furthermore, since the protector P has first and second fixing structures F1 and F2, it can be fixed in the second state. Therefore, the possibility of the protector P unintentionally returning to the first state and the second terminal T2 colliding with the connection terminal CT and causing damage is also reduced.

[0041] Subsequently, the protector P is returned to the first state with respect to both the first hinge portion H1 and the second hinge portion H2. At this time, it is preferable to extend the protector P using the telescopic structure TS so that the corner portion C (see Figure 1) of the second battery stack BS2 does not collide with the second terminal T2 due to the rotation radius of the protector P.

[0042] Next, when the protector P is in the first state, the second terminal T2 and the connection terminal CT of the second battery stack BS2 are connected by bolting or the like. At this time, since the protector P has an expandable structure TS, it can absorb manufacturing tolerances between the battery stacks BS1 and BS2.

[0043] In this way, the inter-stack connection structure 1 and protector P according to this embodiment have hinge portions H1 and H2 that can be bent in a predetermined direction, and are transitionable between a first state and a second state. The first state is the state for connecting the connection terminals CT, and the second state is the state in which the protector P is bent in a predetermined direction using the hinge portions H1 and H2 from the first state. Because the protector P has this structure, after the first terminal T1 is attached to the connection terminal CT of the first battery stack BS1, the bending direction is limited to a predetermined direction by the hinge portions H1 and H2. Therefore, it is prevented that the protector P will bend in an unexpected direction. This reduces the possibility that the protector P will bend in an unexpected direction and the second terminal T2 will come into contact with other members, causing damage or a short circuit. Thus, it is possible to provide an inter-stack connection structure 1 that can reduce the possibility of damage to terminal fittings or short circuits when the connection terminals CT of battery stacks BS1 and BS2 are not adjacent to each other.

[0044] Furthermore, the protector P has fixing structures F1 and F2 that can fix its position in the second state. Therefore, the possibility that the protector P may unintentionally return to the first state after being in the second state, causing the second terminal T2 to collide with the connection terminal CT of the second battery stack BS2 and be damaged, is reduced. Thus, it is possible to provide an inter-stack connection structure 1 that can further reduce the possibility of damage to the terminal fittings.

[0045] Furthermore, the protector P has an expandable and retractable structure TS. Therefore, for example, if the electric wires W are bent and stored inside the protector P, it can accommodate the manufacturing tolerances of the battery stacks BS1 and BS2 by expanding and contracting.

[0046] Although the present invention has been described above based on embodiments, the present invention is not limited to the above embodiments, and modifications may be made without departing from the spirit of the invention, and if possible, publicly known or well-known technologies may be combined.

[0047] For example, in the above embodiment, the protector P had two hinge parts H1 and H2, but it is not limited to this, and only one of the hinge parts H1 and H2 may be present. Furthermore, the protector P has fixing structures F1 and F2, but it is not limited to this, and it does not have to have fixing structures. Also, the fixing structures F1 and F2 do not need to be fixed in position in the first state, as long as their position can be fixed in at least the second state.

[0048] Furthermore, although the protector P has an expandable structure TS, it does not need to have an expandable structure TS if tolerances can be absorbed in other parts, such as if the first and second terminals T1 and T2 have some flexibility. [Explanation of symbols]

[0049] 1: Inter-stack connection structure BC: Battery cell BP: Battery pack BS1: First battery stack BS2: Second battery stack CT: Connection terminal F1: 1st fixed structure (fixed structure) F2:Second fixed structure (fixed structure) H1: First hinge section (hinge section) H2: Second hinge section (hinge section) P: Protector T1: First terminal T2: Second terminal TS: Stretchable structure W: Electric wire

Claims

1. A battery pack comprising first and second battery stacks having stacked battery cells and connection terminals on a specific direction, wherein the second battery stack is provided on the specific direction side of the first battery stack, and the connection terminals are electrically connected to each other, A first terminal electrically connectable to the connection terminal of the first battery stack, A second terminal electrically connectable to the connection terminal of the second battery stack, A protector formed in a hollow shape, A wire, one end of which is connected to the first terminal and the other end of which is connected to the second terminal, is inserted into the protector. The protector has a hinge portion that can be bent in a predetermined direction, and is transitionable between a first state for connecting the connection terminals and a second state obtained by bending the protector in the predetermined direction using the hinge portion from the first state. A stack-to-stack connection structure characterized by the following:

2. The protector has a fixing structure that allows it to be fixed in position in the second state. The inter-stack connection structure according to feature 1.

3. The protector has an expandable and retractable structure. The inter-stack connection structure according to feature 1.

4. A hollow protector that houses wires connected to both a first terminal electrically connectable to the connection terminal of the first battery stack and a second terminal electrically connectable to the connection terminal of the second battery stack, in a first and second battery stack having stacked battery cells and connection terminals on a specific direction, It has a hinge portion that can be bent in a predetermined direction, and is transitionable between a first state for connecting the connection terminals and a second state in which it is bent in the predetermined direction by the hinge portion from the first state. A protector characterized by the following features.

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