JP7772155B2 - Power storage device - Google Patents

Description

The present invention relates to an energy storage device that includes an energy storage element and a wiring holding member that holds wiring electrically connected to the energy storage element.

Traditionally, there have been monitoring devices that monitor the status of a power storage device equipped with one or more power storage elements. For example, Patent Document 1 discloses a battery monitoring device that includes a high-voltage connector electrically connected to a battery and a low-voltage connector connected to a host microcontroller. In this battery monitoring device, the high-voltage connector and the low-voltage connector are arranged on opposing sides of the housing when viewed from above.

JP 2016-115647 A

For example, power storage devices connected to external devices such as the battery monitoring device mentioned above are also provided with connectors for connecting to external wiring. Because this connector is the electrical connection point between the power storage device and the external device, when the power storage device is installed in a mobile device such as an electric vehicle (EV) to drive or start the mobile device, it is necessary to devise ways to protect it from impacts. In particular, high safety is required for the connectors electrically connected to the storage elements of the power storage device.

As a result, if the connector electrically connected to the energy storage element is placed at the edge of the housing (the exterior body of the energy storage device), as in the conventional battery monitoring device described above, the connector may be susceptible to impact.

The present invention was developed by the inventors by focusing on the above-mentioned problem, and aims to provide a highly safe energy storage device equipped with a connector that allows external wiring to be attached and detached.

In order to achieve the above-mentioned object, one embodiment of the present invention provides an energy storage device comprising: an energy storage element; a first wiring electrically connected to the energy storage element; a flat, rectangular wiring holding member that holds the first wiring; and a first connector connected to the first wiring, the first connector being attached to the wiring holding member and allowing external wiring to be attached and detached, the wiring holding member having a restricting portion that is a claw-shaped portion or a protrusion-shaped portion, the restricting portion holding the first wiring, the first connector having a connection port arranged in a second direction that intersects with a first direction in which the wiring holding member and the first connector are arranged, and the restricting portion being located in the second direction of the connection port when viewed from the first direction. Furthermore, a power storage device according to another aspect of the present invention may include an energy storage element, a first wiring electrically connected to the energy storage element, a flat, rectangular wiring holding member that holds the first wiring, a first connector connected to the first wiring, the first connector attached to the wiring holding member and to which external wiring can be attached and detached, and an inner lid disposed between the energy storage element and the wiring holding member, wherein the inner lid holds the wiring holding member and also holds the energy storage element. Furthermore, a power storage device according to another aspect of the present invention may include an energy storage element, a first wiring electrically connected to the energy storage element, the wiring holding member that holds the first wiring, and a first connector connected to the first wiring, the first connector positioned in a central portion of the wiring holding member and to which external wiring can be attached and detached.

With this configuration, the first wiring electrically connected to the energy storage element is provided in the energy storage device while being held by the wiring holding member. Therefore, for example, during manufacturing (assembly) of the energy storage device, the first wiring can be incorporated into the energy storage device while held by the wiring holding member. This makes it less likely for the first wiring to become pinched between components. Also, for example, compared to when the first wiring has a high degree of freedom of movement, the likelihood of defects such as disconnection of the first wiring is reduced. Furthermore, since the first connector is located in the center of the wiring holding member, the possibility of damage to the first connector, which is electrically connected to the energy storage element, is reduced, for example, in the event of a collision accident involving a mobile vehicle equipped with the energy storage device. In other words, the occurrence of unsafe events such as external short circuits due to damage to the first connector is suppressed. As such, the energy storage device according to this aspect is equipped with a connector that allows external wiring to be detached, making it a highly safe energy storage device.

Furthermore, the energy storage device according to one aspect of the present invention may further include a second wiring that is a wiring for a lower voltage than the first wiring, the second wiring being held by the wiring holding member, and a second connector that is connected to the second wiring and is located at an end of the wiring holding member.

With this configuration, as described above, in an energy storage device in which the possibility of damage to the first high-voltage connector in the event of a collision or other accident is reduced, the external wiring can be easily attached and detached to the second low-voltage connector at the end of the wiring holding member.

If excessive external force is applied to the connector due to, for example, a collision between a moving object and an object and the mobile vehicle carrying the power storage device, or if external wiring is forcibly attached or detached from the connector, the connector may be damaged. If the connector is damaged, the status of the power storage device may not be properly checked, or safety issues such as an external short circuit may occur.

In this energy storage device, the first connector, which is subject to a relatively high voltage, is less likely to be damaged in an emergency such as a collision, and the second connector, which is subject to a relatively low voltage, is less likely to be damaged when the external wiring is attached or detached (at least when the external wiring is attached or detached). This results in a highly safe energy storage device.

Furthermore, in an energy storage device according to one aspect of the present invention, the wiring holding member may have a restricting portion that restricts the first wiring and the second wiring to a position aligned within the first region in a direction intersecting the alignment direction of the energy storage element and the wiring holding member.

With this configuration, for example, when the wiring holding member is placed on top of the energy storage element, the first wiring and the second wiring do not overlap vertically, at least within the first region, thereby suppressing an increase in vertical size. Furthermore, when a cover or the like is placed to cover the wiring holding member, the possibility of the first wiring or second wiring being broken due to pressure from the cover is reduced.

Furthermore, the energy storage device according to one aspect of the present invention may further include a cover member that covers the wiring holding member from the side opposite the energy storage element, and the cover member may have a lower surface portion formed at a position facing the first region that forms an outer surface closer to the wiring holding member than other portions.

With this configuration, the space formed by the recessed lower surface of the cover member can be used to place external wiring or electrical equipment such as a control board. In other words, the safety of the power storage device is ensured while making effective use of the space around the power storage device.

Furthermore, in the energy storage device according to one aspect of the present invention, the first wiring and the second wiring may be arranged so as to bypass the second region on the opening side of the first connector.

This configuration ensures ease of attachment and detachment of external wiring to the first connector located in the center of the wiring holding member. This reduces the possibility of damage to the first connector when attaching or detaching external wiring to or from the first connector.

Furthermore, in the energy storage device according to one aspect of the present invention, the wiring holding member may have a wall portion erected along at least a portion of the periphery of the second region.

With this configuration, the presence of the wall portion makes it possible to forcibly position the first wiring and the second wiring outside the second region when or after placing the first wiring and the second wiring on the wiring holding member. This makes it easier to attach and detach the external wiring to and from the first connector, for example.

The present invention can be realized not only as an electricity storage device, but also as a wiring holding member provided in the electricity storage device.

The present invention provides a highly safe energy storage device equipped with a connector that allows external wiring to be attached and detached.

1 is a perspective view showing the appearance of a power storage device according to an embodiment; FIG. 2 is a first exploded perspective view illustrating components of the electricity storage device according to the embodiment when disassembled. FIG. 2 is a second exploded perspective view illustrating the components of the electricity storage device according to the embodiment when disassembled. FIG. 2 is a plan view showing a layout of first wiring according to the embodiment. FIG. 10 is a plan view showing a layout of second wiring according to the embodiment. FIG. 2 is an enlarged perspective view of a portion of the harness plate according to the embodiment. 1 is a plan view showing a first configuration example of a battery pack according to an embodiment; FIG. 10 is a plan view showing a second configuration example of the battery pack according to the embodiment. FIG. 10 is a cross-sectional view showing a configuration around a lid of an electricity storage device according to a modified example of the embodiment. FIG. 10 is a plan view showing the configuration of an electricity storage device according to a modified example of the embodiment.

The following describes an energy storage device according to an embodiment of the present invention, with reference to the drawings. Note that the embodiments described below are comprehensive or specific examples. The numerical values, shapes, materials, components, component placement positions, and connection configurations shown in the following embodiments are merely examples and are not intended to limit the present invention. Furthermore, among the components in the following embodiments, components that are not described in the independent claims that represent the highest concepts are described as optional components. Furthermore, the dimensions and other details shown in the drawings are not strictly accurate.

In the following description and drawings, the X-axis direction is defined as the arrangement direction of the electrode terminals of a single energy storage element, the direction in which the short sides of the energy storage element's container face each other, or the direction in which the long sides of the energy storage device's exterior are facing each other. The Y-axis direction is defined as the arrangement direction of multiple energy storage elements, the direction in which the long sides of the energy storage element's container face each other, the thickness direction of the container, or the direction in which the short sides of the energy storage device's exterior are facing each other. The Z-axis direction is defined as the arrangement direction of the energy storage device's exterior body, energy storage element, inner lid, harness plate, and lid, the arrangement direction of the energy storage element's container body and lid, or the up-down direction. The X-axis direction, Y-axis direction, and Z-axis direction intersect each other (orthogonal in this embodiment). Depending on the usage mode, the Z-axis direction may not be the up-down direction; however, for convenience of explanation, the Z-axis direction will be described below as the up-down direction. In the following description, for example, the positive X-axis direction refers to the direction of the arrow on the X-axis, and the negative X-axis direction refers to the opposite side of the positive X-axis direction. The same applies to the Y-axis and Z-axis directions.

(Embodiment)
First, the configuration of an energy storage device 10 according to an embodiment will be described. Fig. 1 is a perspective view showing the appearance of the energy storage device 10 according to the embodiment. Fig. 2 is a first exploded perspective view showing each component when the energy storage device 10 according to the embodiment is disassembled. Fig. 3 is a second exploded perspective view showing each component when the energy storage device 10 according to the embodiment is disassembled. Note that in Fig. 3, the exterior body 11 and the inner lid 30 are omitted from the illustration in order to clearly show the relationship between the harness plate 50 and members fixed to the harness plate 50.

The power storage device 10 is a device that can charge with electricity from an external source and discharge electricity to an external source. For example, the power storage device 10 is a battery module used for power storage purposes, power supply purposes, etc. Specifically, the power storage device 10 is used as a battery for driving or starting the engine of a mobile object such as an electric vehicle (EV), hybrid electric vehicle (HEV), or plug-in hybrid electric vehicle (PHEV), as well as motorcycles, personal watercraft, snowmobiles, agricultural machinery, or construction machinery.

As shown in Figures 1 and 2, the energy storage device 10 includes an exterior body 11 consisting of a lid body 100 and an exterior body main body 200, and a plurality of energy storage elements 20, an inner lid 30, a plurality of bus bars 40, a harness plate 50, internal wiring 65, and the like, housed inside the exterior body 11.

The exterior body 11 is a rectangular (box-shaped) container (module case) that constitutes the exterior body of the energy storage device 10. In other words, the exterior body 11 is positioned outside the energy storage elements 20 and harness plate 50, etc., and positions these energy storage elements 20, etc. in predetermined positions to protect them from impacts and the like. The exterior body 11 is also made of an insulating material such as polycarbonate (PC), polypropylene (PP), polyethylene (PE), polyphenylene sulfide resin (PPS), polybutylene terephthalate (PBT), or ABS resin. This prevents the energy storage elements 20, etc. from coming into contact with metal members, etc.

The exterior body 11 has a flat, rectangular lid body 100 that forms the lid (outer lid) of the exterior body 11, and an exterior body main body 200 that forms the main body of the exterior body 11. The lid body 100 is an example of a cover member that covers the harness plate 50 from the side opposite the energy storage element 20. The exterior body main body 200 is a rectangular, cylindrical housing with a bottom and an opening formed in it. In other words, the lid body 100 is positioned so as to cover the opening of the exterior body main body 200. The lid body 100 and the exterior body main body 200 may be made of the same material, or may be made of different materials.

In addition, opening 100a, which is a rectangular through-hole, is formed in the center of lid body 100, and opening 100b, which is a rectangular notch, is formed in the corners of lid body 100 on the positive side in the X-axis direction and on both sides of the Y-axis direction. Lid body 100 also has opening 100c, which is a rectangular notch, formed in the center of lid body 100 in the X-axis direction and on the negative side in the Y-axis direction. Lid body 100 also has a bottom surface portion 105 that forms the outer surface closer to the harness plate 50 than other portions.

The energy storage elements 20 are secondary batteries (single cells) that can charge and discharge electricity, and more specifically, are non-aqueous electrolyte secondary batteries such as lithium-ion secondary batteries. The energy storage elements 20 have a flattened rectangular (square) shape, and in this embodiment, eight energy storage elements 20 (energy storage elements 20A to 20H) are arranged in the Y-axis direction. The shape of the energy storage elements 20 and the number of energy storage elements 20 arranged are not limited. Furthermore, the energy storage elements 20 are not limited to non-aqueous electrolyte secondary batteries, and may be secondary batteries other than non-aqueous electrolyte secondary batteries, capacitors, or even primary batteries that allow stored electricity to be used without the user having to charge them.

Specifically, the energy storage element 20 includes a metal container 21, the lid of which is provided with metal electrode terminals, a positive electrode terminal 22 and a negative electrode terminal 23. The lid of the container 21 may also be provided with a liquid injection section for injecting electrolyte, and a gas exhaust valve for releasing gas when pressure inside the container 21 increases. Inside the container 21, electrodes (also referred to as the energy storage element or power generation element) and current collectors (positive electrode current collector and negative electrode current collector) are arranged, and an electrolyte (nonaqueous electrolyte) is enclosed, but detailed description thereof will be omitted.

In this embodiment, the positive electrode terminal 22 and the negative electrode terminal 23 are bolt terminals with threaded bolt portions that protrude from the lid portion of the container 21 toward the lid body 100 (upward, i.e., toward the positive side in the Z-axis direction). The negative electrode terminal 23 of the energy storage element 20A and the positive electrode terminal 22 of the energy storage element 20H, which are the outermost electrode terminals of the multiple energy storage elements 20, are exposed from openings 100b formed in the corners of the lid body 100 on the positive side in the X-axis direction and on both sides in the Y-axis direction. These outermost electrode terminals are connected to external terminals (not shown) or function as external terminals, allowing the energy storage device 10 to charge with electricity from the outside and discharge electricity to the outside.

The inner lid 30 is a flat, rectangular member that constitutes the inner lid of the exterior body 11 and serves to reinforce the exterior body main body 200. The inner lid 30 is disposed between the harness plate 50 and the energy storage element 20, holding the harness plate 50 from below and holding the energy storage element 20 from above. The inner lid 30 is made of an insulating material such as PC, PP, PE, PPS, PBT, or ABS resin. Openings 31 are formed in the inner lid 30 at the corners on the positive side in the X-axis direction and on both sides in the Y-axis direction. The thermistor 63 and detection terminals 80, described below, are disposed in these openings 31.

The bus bar 40 is a rectangular plate-shaped member disposed on the multiple energy storage elements 20 (on the inner lid 30) and electrically connects the electrode terminals of the multiple energy storage elements 20. The bus bar 40 is formed of a conductive metal material, such as copper, copper alloy, aluminum, or aluminum alloy. Specifically, through holes are formed in the bus bar 40, and bolt portions of the electrode terminals of the energy storage elements 20 are inserted into the through holes. Nuts 90 (see FIG. 3) are then fastened to the bolt portions, thereby connecting the bus bar 40 to the electrode terminals. In this embodiment, the bus bar 40 connects the positive electrode terminal 22 of one of two adjacent energy storage elements 20 to the negative electrode terminal 23 of the other. This connects the eight energy storage elements 20 in series. Note that the connection of the energy storage elements 20 is not limited to the above, and any combination of series and parallel connections may be used.

In addition, in this embodiment, a detection terminal 80, which is a terminal for detecting voltage, is arranged in contact with each of the multiple bus bars 40. Specifically, the detection terminal 80 is arranged on the upper surface of the bus bar 40, and the bus bar 40 and the detection terminal 80 are fastened together by a nut 90. In other words, the nut 90 that secures the bus bar 40 to the electrode terminal of the energy storage element 20 secures the detection terminal 80 in contact with the bus bar 40.

Furthermore, as described above, a thermistor 63 is disposed at the detection terminals 80 located at the negative terminal 23 of storage element 20A and the positive terminal 22 of storage element 20H, which are the outermost electrode terminals of the multiple storage elements 20. In other words, in this embodiment, the thermistor 63 measures the temperature of the positive terminal 22 of storage element 20H, which is the overall positive terminal of the storage element unit made up of storage elements 20A to 20H connected in series, and the negative terminal 23 of storage element 20A, which is the overall negative terminal of the storage element unit.

The harness plate 50 is an example of a wiring holding member, and is a flat, rectangular member on which electrical components such as the internal wiring 65, first connector 85, and second connector 86 are arranged. The harness plate 50 is disposed between the energy storage device 20 and the lid 100.

The harness plate 50 is made of an insulating material such as PC, PP, PE, PPS, PBT, or ABS resin. In other words, the harness plate 50 is placed on the inner cover 30 and holds the internal wiring 65, first connector 85, second connector 86, etc., insulating the internal wiring 65, etc. from other components and regulating the position of the internal wiring 65, etc.

The internal wiring 65 has a first wiring 65a that electrically connects each electrode terminal of the energy storage element 20 to the first connector 85, and a second wiring 65b that electrically connects the two thermistors 63 to the second connector 86, and is attached to the harness plate 50. The internal wiring 65 is held in the harness plate 50, for example, by being hooked onto a first restricting portion 51, which is a claw-shaped portion provided on the harness plate 50. Details of the attachment structure of the internal wiring 65 to the harness plate 50 will be described later using Figure 5.

In this embodiment, the first connector 85 is a connector having multiple pins within the connection port 85a, and the second connector 86 is a connector having multiple pins within the connection port 86a. In other words, connectors with multiple pin holes provided at the ends of external wiring are inserted into the connection port 85a of the first connector 85 and the connection port 86a of the second connector 86, respectively.

The first connector 85 is attached to the harness plate 50 with its rear end supported by the first connector support portion 55a of the harness plate 50. The second connector 86 is attached to the harness plate 50 with its rear end supported by the second connector support portion 55b of the harness plate 50. The rear end of each of the first connector 85 and the second connector 86 opposite the connection port (85a or 85b) is supported by the connector support portion (55a or 55b), thereby preventing them from floating up.

The first wiring 65a and second wiring 65b will be described using Figures 4A and 4B in addition to Figure 3. Figure 4A is a plan view showing the layout of the first wiring 65a according to the embodiment, and Figure 4B is a plan view showing the layout of the second wiring 65b according to the embodiment. Note that to make the layout of the first wiring 65a and the second wiring 65b easier to see, dashed lines are drawn on the first wiring 65a in Figure 4A, and dashed lines are drawn on the second wiring 65b in Figure 4B. Furthermore, to make the positions of the detection terminal 80 and thermistor 63 easier to see, the detection terminal 80 is drawn with diagonal lines in Figure 4A, and the thermistor 63 is drawn with a dot in Figure 4B.

The first wiring 65a is a wiring for a relatively high voltage that is electrically connected to each of the multiple energy storage elements 20. Specifically, as shown in Figures 3 and 4A, the first wiring 65a is a wiring that connects the nine detection terminals 80 (80a to 80i) to the first connector 85. As shown in Figures 3 and 4B, the second wiring 65b is a wiring that connects the two thermistors 63 to the second connector 86. In other words, the second wiring 65b is a wiring through which a current for temperature detection flows, and is therefore a wiring for a lower voltage than the first wiring 65a.

As shown in Figures 4A and 4B, the first connector 85 is disposed in the center of the harness plate 50, and the second connector 86 is disposed at an end of the harness plate 50. External wiring is detachably connected to each of the first connector 85 and the second connector 86. For example, a control device that controls the energy storage device 10 can measure the voltage of each energy storage element 20 of the energy storage device 10 and the temperature of the energy storage device 10 via the first connector 85, the second connector 86, and the external wiring connected to each of these connectors.

In this embodiment, of the nine detection terminals 80, the two outermost detection terminals 80, detection terminals 80a and 80i, are each connected to an electrode terminal of the energy storage element 20. Specifically, detection terminal 80a is connected to the negative electrode terminal 23 of energy storage element 20A, and detection terminal 80i is connected to the positive electrode terminal 22 of energy storage element 20H. Note that detection terminal 80a and detection terminal 80i are each fixed to the electrode terminal with a nut not shown in Figure 3, etc.

Furthermore, as shown in Figures 3 and 4A, each of the detection terminals 80b to 80h is connected to a bus bar 40. Specifically, each of the detection terminals 80b to 80h is fixed in contact with one bus bar 40 by a nut 90 as described above. One bus bar 40 is connected to one positive terminal 22 and the other negative terminal 23 of two adjacent energy storage elements 20. In other words, each of the detection terminals 80b to 80h is electrically connected to one positive terminal 22 and the other negative terminal 23 of the corresponding two energy storage elements 20. For example, the detection terminal 80b is electrically connected to the positive terminal 22 of energy storage element 20A and the negative terminal 23 of energy storage element 20B.

With the above configuration, the control device connected to the first connector 85 can measure the voltage of, for example, one storage element 20 by measuring the potential difference between the two detection terminals 80. For example, the voltage of storage element 20B can be measured by measuring the potential difference between detection terminal 80b and detection terminal 80c.

The first wiring 65a can also be used as wiring to equalize the voltages of the storage elements 20. For example, if the voltage of storage element 20B is higher than the voltages of the other storage elements 20, the control device connected to the first connector 85 can discharge storage element 20B by connecting detection terminal 80b and detection terminal 80c via a discharge circuit (balancing circuit). This reduces the voltage of storage element 20B. In other words, the voltages of multiple storage elements 20 are equalized.

As shown in FIG. 4B , a thermistor 63 is attached to each of the detection terminals 80a and 80i, and the two thermistors 63 are connected to the second connector 86 via second wiring 65b. Specifically, a pair of electric wires is connected to each of the two thermistors 63 as the second wiring 65b. The control device connected to the second connector 86 can measure the resistance value of the thermistor 63 via this pair of electric wires, thereby measuring the temperature of the energy storage device 10 thermally connected to that thermistor 63.

As described above, the energy storage device 10 according to this embodiment includes an energy storage element 20, a first wiring 65a electrically connected to the energy storage element 20, a harness plate 50 that holds the first wiring 65a, and a first connector 85 connected to the first wiring 65a, the first connector 85 being located in the center of the harness plate 50 and allowing external wiring to be attached and detached.

With this configuration, the first wiring 65a electrically connected to the energy storage element 20 is provided in the energy storage device 10 while being held by the harness plate 50. Therefore, for example, during the manufacturing (assembly) of the energy storage device 10, the first wiring 65a can be incorporated into the energy storage device 10 while held by the harness plate 50. This reduces, for example, the likelihood of the first wiring 65a being pinched between components. Furthermore, compared to a case where the first wiring 65a has a high degree of freedom of movement, the likelihood of malfunctions such as disconnection of the first wiring 65a or severing of the connection between the first wiring 65a and the detection terminal 80 is reduced. Furthermore, since the first connector 85 is located in the center of the harness plate 50, the likelihood of damage to the first connector 85, which is electrically connected to the energy storage element 20, is reduced in the event of, for example, a collision accident involving a vehicle equipped with the energy storage device 10. In other words, the occurrence of unsafe events such as an external short circuit due to damage to the first connector 85 is suppressed.

Here, assume that the energy storage device 10 is installed in a vehicle such as an EV or PHEV, with the harness plate 50 positioned above the multiple energy storage elements 20, i.e., with the positive Z-axis direction facing upward in this embodiment. In this case, for example, if the vehicle collides with an object while traveling, the energy storage device 10 will be subjected to impact primarily from the side (a direction parallel to the XY plane). Under these conditions, a portion of the harness plate 50 will always be present on the side of the first connector 85, which is located in the center of the harness plate 50 in a plan view (when viewed from the direction in which the harness plate 50 and the multiple energy storage elements 20 are aligned). Therefore, for example, a portion of the harness plate 50 surrounding the first connector 85 functions as a buffer member that absorbs impact. As a result, impact on the first connector 85 is reduced. In other words, the first connector 85 is positioned on the harness plate 50 in a position that is less susceptible to impact resulting from a collision or other accident.

As such, the energy storage device 10 according to this embodiment is equipped with a first connector 85 to which external wiring can be attached and detached, making it a highly safe energy storage device 10.

In this embodiment, for example, as shown in FIG. 1, an opening 100a is provided in the center of the lid 100 that covers the harness plate 50. Therefore, even when the lid 100 is placed above the harness plate 50, the connection port 85a of the first connector 85 (the opening through which the end of the external wiring is inserted and removed) is exposed from the opening 100a. Therefore, external wiring can be attached to and removed from the first connector 85.

In addition, in this embodiment, the harness plate 50 is arranged between the positive electrode terminal 22 and the negative electrode terminal 23 of each of the multiple (eight in this embodiment) storage elements 20. In other words, the harness plate 50 is arranged using the space between the positive electrode terminal 22 and the negative electrode terminal 23 that protrude from the container 21 of the storage element 20.

That is, the harness plate 50 is located in the center of the energy storage device 10, for example, in the alignment direction (X-axis direction) of the positive terminal 22 and the negative terminal 23. Therefore, for example, if an impact is applied to the energy storage device 10 from the side in the X-axis direction, the effect of that impact on the harness plate 50 is reduced. As a result, for example, the first connector 85 is more reliably protected against that impact.

In this embodiment, the length of the harness plate 50 in the arrangement direction (Y-axis direction) of the multiple energy storage elements 20 is approximately the same as the width in the Y-axis direction of the energy storage element unit composed of the multiple energy storage elements 20 (see, for example, Figure 4A). Therefore, in a plan view, it can be said that the first connector 85 is located in the center of the energy storage device 10, and the second connector 86 is located at the end of the energy storage device 10.

The energy storage device 10 according to this embodiment also includes a second wiring 65b, which is a wiring for a lower voltage than the first wiring 65a and is held by the harness plate 50, and a second connector 86 connected to the second wiring 65b and located at the end of the harness plate 50.

With this configuration, as described above, in the energy storage device 10, the possibility of damage to the high-voltage first connector 85 in the event of a collision or other accident is reduced, while the ease of attaching and detaching external wiring to the low-voltage second connector 86 at the end of the harness plate 50 is ensured.

If excessive external force is applied to the connector due to, for example, a collision between a moving object and the power storage device 10 mounted thereon, or due to the external wiring being forcibly attached or detached from the connector, the connector may be damaged. If the connector is damaged, the status of the power storage device 10 may not be properly checked, or safety issues such as an external short circuit may occur.

In the energy storage device 10 according to this embodiment, the first connector 85, which is subjected to a relatively high voltage, is designed to reduce the possibility of damage in an emergency such as a collision. Furthermore, the second connector 86, which is subjected to a relatively low voltage, is designed to ensure ease of connection and disconnection of external wiring, thereby reducing the possibility of damage to the second connector 86 when connecting and disconnecting external wiring. This results in a highly safe energy storage device.

The harness plate 50 according to this embodiment also has a structure for regulating the position of the internal wiring 65, which tends to become complicated. This structure will be explained using Figure 5 in addition to Figures 4A and 4B described above.

Figure 5 is an enlarged perspective view of a portion of the harness plate 50 according to the embodiment. Specifically, Figure 5 shows an enlarged view of the portion of the harness plate 50 in front of the first connector 85 (the connection port 85a side).

As shown in FIG. 5, the harness plate 50 according to this embodiment has restricting portions (51, 52) that restrict the first wiring 65a and the second wiring 65b to a position aligned in a direction intersecting the alignment direction (Z-axis direction) of the energy storage device 20 and the harness plate 50 within the first region 56a (see FIGS. 4A and 4B).

Specifically, in this embodiment, the harness plate 50 is provided with a first restricting portion 51, which is a claw-shaped portion, and a second restricting portion 52, which is a protrusion-shaped portion, as restricting portions. Each of the multiple first restricting portions 51 hooks onto and holds the first wiring 65a or the second wiring 65b. Furthermore, one set of the multiple second restricting portions 52 sandwiches and holds the first wiring 65a or the second wiring 65b. Each of the first wiring 65a and the second wiring 65b is restricted by at least one of the first restricting portion 51 and the second restricting portion 52 to a position aligned in a direction (along the XY plane) along the top surface of the harness plate 50 (one surface of the internal wiring 65). As a result, in the first region 56a of the harness plate 50, the first wirings 65a do not overlap each other vertically, the second wirings 65b do not overlap each other vertically, and the first wirings 65a and the second wirings 65b do not overlap each other vertically.

As such, with the harness plate 50 according to this embodiment, the first wiring 65a and the second wiring 65b do not overlap vertically, at least within the first region 56a, thereby suppressing an increase in the vertical size. Specifically, with the harness plate 50 according to this embodiment, the first wiring 65a and the second wiring 65b can be held by utilizing the space between the multiple energy storage elements 20 and the lid 100 without wasting that space. More specifically, as described above, the harness plate 50 is disposed in the space between the positive terminal 22 and the negative terminal 23. Therefore, an increase in the size of the energy storage device 10 due to the presence of the harness plate 50 within the energy storage device 10 is suppressed.

Furthermore, even if the lid body 100 (see Figures 1 and 2) is positioned above the harness plate 50, the possibility of the first wiring 65a or the second wiring 65b being broken due to pressure from the lid body 100 is reduced. This contributes to improving the safety of the energy storage device 10.

In this embodiment, the heights of the first and second restricting portions 51 and 52 (heights from the arrangement surface 50a of the harness plate 50 on which the internal wiring 65 is located) are the same (including approximately the same). Furthermore, the bottom surface 105 of the lid 100, which faces the first region 56a, is positioned at a height that allows it to abut against the first and second restricting portions 51 and 52. Therefore, the first and second restricting portions 51 and 52 also function as supports to prevent the lid 100 (bottom surface 105) from pressing against the first wiring 65a and second wiring 65b.

Furthermore, in this embodiment, the portion (coated portion) between both ends of each of the first wiring 65a and the second wiring 65b (more specifically, each of the multiple electric wires that make up the first wiring 65a and the second wiring 65b) is held by the restricting portion (at least one of the first restricting portion 51 and the second restricting portion 52) of the harness plate 50. Therefore, the posture or position of each of the flexible first wiring 65a and the second wiring 65b inside the exterior body 11 can be stably maintained.

Furthermore, as shown in Figures 4A, 4B, and 5, in the harness plate 50 according to this embodiment, the first wiring 65a and the second wiring 65b are arranged so as to bypass the second region 56b on the opening (connection port 85a) side of the first connector 85.

The second region 56b is the region to the side of the first connector 85 in a plan view, on the side where the connection port 85a is provided. For example, the size and shape of the second region 56b are determined by the size and shape of the connector provided at the end of the external wiring to be inserted into the connection port 85a.

This configuration ensures ease of attachment and detachment of external wiring, even for the first connector 85 located in the center of the harness plate 50. This reduces the possibility of damaging the first connector 85 when attaching or detaching external wiring to or from the first connector 85. In other words, it reduces the possibility of performing an operation that places unnecessary stress on the first connector 85, such as inserting external wiring at an angle into the connection port 85a of the first connector 85 due to a lack of space in front of the connection port 85a.

In addition, in this embodiment, the connection port 85a of the first connector 85 opens in a direction along the arrangement surface 50a of the harness plate 50, on which the internal wiring 65 is arranged. In other words, when an external wiring is inserted into the connection port 85a of the first connector 85, the external wiring protrudes from the first connector 85 in a direction along the arrangement surface 50a. Therefore, for example, the external wiring can be connected to the first connector 85 in a position that prevents it from protruding from the energy storage device 10. This can reduce the possibility of damage to the external wiring or the first connector 85 due to external force being applied to the external wiring, for example.

The harness plate 50 also has a wall portion 54 erected along at least a portion of the periphery of the second region 56b. The presence of the wall portion 54 on the harness plate 50 thus makes it possible to forcibly position the first wiring 65a and the second wiring 65b outside the second region 56b when or after the first wiring 65a and the second wiring 65b are arranged on the harness plate 50. This, for example, makes it easier to attach and detach external wiring to and from the first connector 85. This further reduces the possibility of damage to the first connector 85 when attaching and detaching external wiring to and from the first connector 85.

In this embodiment, the wall portion 54 is positioned in the harness plate 50 so as to surround the second region 56b. This allows the first wiring 65a and the second wiring 65b to be substantially completely removed from the second region 56b. Furthermore, for example, when a worker connects or disconnects external wiring to or from the first connector 85 after the lid 100 has been placed, the worker's fingers are prevented from touching the first wiring 65a or the second wiring 65b. In other words, safety is improved when connecting or disconnecting external wiring to or from the first connector 85.

It is also possible to configure a single battery pack by combining multiple power storage devices 10 according to this embodiment. Therefore, the battery pack 1 according to this embodiment will be described using Figures 6 and 7.

Figure 6 is a plan view showing a first configuration example of a battery pack 1 according to an embodiment, and Figure 7 is a plan view showing a second configuration example of a battery pack 1 according to an embodiment. In Figure 7, external wiring is schematically represented by thick lines.

As described above, the lid 100 provided in the energy storage device 10 according to this embodiment has a bottom surface 105 that forms an outer surface closer to the harness plate 50 than other portions. This bottom surface 105 is located opposite the first region 56a of the harness plate 50 (see Figures 4A and 4B).

That is, as explained using Figure 5, in the first region 56a, the first wiring 65a and the second wiring 65b are arranged so that they do not overlap in the vertical direction, making it possible to form the lower surface portion 105 at a position opposite the first region 56a.

In this embodiment, the bottom surface 105 is provided as a recessed portion in the lid 100 between the protruding portions 101 and 102, and this recessed portion can be used to arrange external wiring as shown in Figure 6.

Specifically, the battery pack 1 shown in FIG. 6 includes three power storage devices 10: a first power storage device 10A, a second power storage device 10B, and a third power storage device 10C; and three conductive members 12: a first conductive member 12A, a second conductive member 12B, and a third conductive member 12C. The first conductive member 12A is an external wiring (external harness) connected to the first power storage device 10A. Similarly, the second conductive member 12B and the third conductive member 12C are external wiring (external harness) connected to the second power storage device 10B and the third power storage device 10C.

The first conductive member 12A is connected to the first connector 85 of the first power storage device 10A, the second conductive member 12B is connected to the first connector 85 of the second power storage device 10B, and the third conductive member 12C is connected to the first connector 85 of the third power storage device 10C. In this case, the first conductive member 12A is arranged on the bottom surface 105 of the first power storage device 10A, and the second conductive member 12B is arranged on the bottom surface 105 of the first power storage device 10A and the bottom surface 105 of the second power storage device 10B. Similarly, the third conductive member 12C is arranged on the bottom surface 105 of the first power storage device 10A, the bottom surface 105 of the second power storage device 10B, and the bottom surface 105 of the third power storage device 10C.

In addition, each power storage device 10 is provided with, for example, a harness cover 210 (the outline of which is shown by a dashed line in Figure 6) that covers the conductive member 12. This harness cover 210 ensures, for example, a flush connection between the protrusions 101 and 102.

In this way, when the energy storage devices 10 according to this embodiment are arranged so that the bottom surfaces 105 of the energy storage devices 10 are aligned, the bottom surfaces 105 of the energy storage devices 10 form a passage for one or more external wiring. By arranging one or more external wiring in this passage, the battery pack 1 can be constructed without increasing the size in the height direction (Z-axis direction).

Furthermore, the first connectors 85 of each of the multiple power storage devices 10 included in the battery pack 1 are located inward from the ends of the battery pack 1 in a plan view, so even if a mobile vehicle equipped with the battery pack 1 is involved in a collision or other accident, the first connectors 85 are unlikely to be damaged.

Furthermore, when a storage device array configured by arranging multiple storage devices 10 in the X-axis direction is arranged in the Y-axis direction, these storage device arrays can be arranged close to each other, as shown in Figure 7.

Specifically, in a plan view of the energy storage device 10 according to this embodiment, the first connector 85 is located in the center and the second connector 86 is located at the end. Therefore, for example, when two energy storage devices 10 are arranged in the direction in which the first connector 85 and the second connector 86 are aligned (the Y-axis direction), the second connectors 86 of the two energy storage devices 10 are arranged so that they face in opposite directions.

In other words, as shown in FIG. 7 , when a power storage device row including a first power storage device 10A and a second power storage device 10B is arranged alongside a power storage device row including a fourth power storage device 10D and a fifth power storage device 10E, the two power storage device rows are arranged so that the second connectors 86 in each power storage device row face outward. This allows the two power storage device rows to be positioned close to each other and also ensures ease of attachment and detachment of external wiring (conductive members 13) to the second connectors 86.

There is no particular limit to the number of power storage devices 10 included in the battery pack 1. For example, the number of power storage devices 10 may be determined depending on the specifications of the mobile object in which the battery pack 1 is installed. Furthermore, although not shown in Figures 6 and 7, the battery pack 1 may also include a housing that houses the multiple power storage devices 10 included in the battery pack 1.

(Modification)
Next, a modification of the above embodiment will be described. In the above embodiment, the electrode terminals of the energy storage elements 20 are bolt terminals having bolt portions, and the electrode terminals of the energy storage elements 20 and the bus bar 40 are connected to each other by inserting the bolt portions into through holes in the bus bar 40 and fastening nuts to the bolt portions. However, in this modification, the electrode terminals of the energy storage elements do not have bolt portions, but are welded terminals that are connected (joined) to the bus bar by welding.

Figure 8 is a cross-sectional view showing the configuration around the lid body 300 of an energy storage device according to a modified example of this embodiment. Also, Figure 9 is a plan view showing the configuration of an energy storage device according to a modified example of this embodiment. As shown in Figures 8 and 9, the energy storage elements 20 (energy storage elements 20I to 20K in this figure) in this modified example have positive terminals 24 and negative terminals 25 instead of the positive terminals 22 and negative terminals 23 of the energy storage elements 20 in the above-described embodiment. Also, the bus bar 42 in this modified example has a terminal connection portion 42a and an intermediate portion 42b.

The positive electrode terminal 24 and the negative electrode terminal 25 are welded terminals that are connected (joined) to the bus bar 42 by welding. Specifically, the positive electrode terminal 24 and the negative electrode terminal 25 are joined to the terminal connection portion 42a of the bus bar 42 by welding. For example, the positive electrode terminal 24 of the energy storage element 20I is welded to one terminal connection portion 42a of the bus bar 42, and the negative electrode terminal 25 of the energy storage element 20J is welded to the other terminal connection portion 42a of the bus bar 42.

In other words, the terminal connection portion 42a is the portion of the bus bar 42 that connects to the electrode terminal of the energy storage element 20, and two terminal connection portions 42a that connect to the electrode terminals of two different energy storage elements 20 are arranged on one bus bar 42. The middle portion 42b is the portion that is arranged between the two terminal connection portions 42a. The middle portion 42b is a curved portion (hinge portion) that allows the bus bar 42 to expand and contract in the Y-axis and Z-axis directions, and is arranged to protrude from the two terminal connection portions 42a on the positive side in the Z-axis direction.

Furthermore, the lid body 300 in this modified example has a convex portion 310 and a concave portion 320 instead of the concave-convex structure formed to accommodate multiple bolt terminals in the lid body 100 in the above embodiment. In other words, the convex portion 310 is a convex portion with a protruding outer surface that faces the bus bar 42, and the concave portion 320 is a concave portion with a concave outer surface that is positioned adjacent to the convex portion 310.

Here, the convex portion 310 has a first convex portion 311 that is arranged opposite the electrode terminal of the energy storage element 20 (in the figure, the positive electrode terminal 24 and negative electrode terminal 25 of energy storage elements 20I to 20K). In other words, the first convex portion 311 is arranged opposite the terminal connection portion 42a of the bus bar 42. Specifically, the first convex portion 311 is arranged to cover the electrode terminal of the energy storage element 20 and the upper side (the positive side in the Z-axis direction) of the terminal connection portion 42a, and has a shape (rectangular in the figure) that corresponds to the electrode terminal and terminal connection portion 42a in a top view (seen from the Z-axis direction). Furthermore, the first convex portion 311 is arranged to protrude further than the first recess 321 and second recess 322 of the recess 320, which will be described later.

The protrusion 310 also has a second protrusion 312 that is positioned opposite the intermediate portion 42b of the busbar 42. Specifically, the second protrusion 312 is positioned so as to cover the upper side of the intermediate portion 42b (the positive side in the Z-axis direction), and has a shape (rectangular in the figure) that corresponds to the intermediate portion 42b in a top view (as viewed from the Z-axis direction). The second protrusion 312 is also formed to protrude further than the first protrusion 311.

The recess 320 has a first recess 321 disposed between two first protrusions 311 that are disposed opposite the electrode terminals of two different energy storage elements 20 (e.g., the negative electrode terminal 25 of energy storage element 20J and the positive electrode terminal 24 of energy storage element 20K). Specifically, the first recess 321 is disposed opposite the lid portion of the container 21 of the energy storage element 20 between two adjacent bus bars 42, and has a shape (rectangular in the figure) that corresponds to the space between the two bus bars 42 when viewed from above (as viewed from the Z-axis direction).

The recess 320 also has a second recess 322 that is positioned between two first protrusions 311 that are positioned opposite two electrode terminals of the same energy storage element 20 (e.g., the positive electrode terminal 24 and the negative electrode terminal 25 of the energy storage element 20I).

Furthermore, the recess 320 has a third recess 323 that is positioned opposite at least one of the two terminal connection portions 42a and is recessed more than the second convex portion 312. In this modified example, the third recess 323 is the first convex portion 311 described above. In other words, the first convex portion 311 is a convex portion relative to the first recess 321 and the second recess 322, but a concave portion relative to the second convex portion 312, and therefore can also be referred to as the third recess 323.

In the above configuration, as described in Figure 6, the conductive member 12 is placed in the recess 320. In other words, the conductive member 12 is placed in any of the first recess 321, second recess 322, and third recess 323.

Here, for example, if the conductive member 12 is arranged to extend in the X-axis direction (such as the second conductive member 12B and third conductive member 12C in Figure 6), placing the conductive member 12 in the first recess 321 and extending it in the X-axis direction will result in the conductive member 12 interfering with the second protrusion 312.

Specifically, it is possible to place a conductive member 12 in the groove-shaped portion formed by the first recess 321 and the second recess 322, which are positioned opposite each other between the negative terminal 25 of energy storage element 20J and the positive terminal 24 of energy storage element 20K. However, for conductive members 12 (such as the second conductive member 12B and the third conductive member 12C in FIG. 6 ) that extend straight in the X-axis direction across adjacent energy storage devices 10, the second convex portion 312 and the conductive member 12, which are positioned opposite each other between the positive terminal 24 of energy storage element 20J and the negative terminal 25 of energy storage element 20K, will be positioned so that they overlap in the Z-axis direction, increasing the height dimension of the entire unit.

In such a case, by placing the conductive member 12 in the third recess 323 (and second recess 322) on both sides in the X-axis direction, the conductive member 12 can be placed parallel to the X-axis direction. Furthermore, as shown in FIG. 6, when connecting the conductive member 12 to the first connector 85, the conductive member 12 can also be placed in the first recess 321. For example, the first conductive member 12A in FIG. 6 can also be placed in the first recess 321 without any problems.

As for the second conductive member 12B and the third conductive member 12C in Figure 6, another solution to the problem of interference in the Z-axis direction described above is to bend the conductive member 12 between the second recess 322 or adjacent energy storage devices 10, for example, so that the conductive member 12 can be positioned in the first recess 321 while avoiding the second protrusion 312.

The rest of the configuration of this variant is the same as that of the above embodiment, so detailed explanation will be omitted.

The above describes the energy storage device 10 and battery pack 1 according to an embodiment of the present invention, but the present invention is not limited to the above embodiment. In other words, the embodiment disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is indicated by the claims rather than the above description, and is intended to include all modifications within the meaning and scope of the claims.

For example, in the above embodiment, the energy storage device 10 is provided with a harness plate 50 as a wiring holding member, but the wiring holding member does not have to be a member generally recognized as a "plate." For example, it may be a frame-structured member that holds the internal wiring 65, the first connector 85, and the second connector 86.

Furthermore, the component electrically connected to the second connector 86 via the second wiring 65b does not have to be the thermistor 63. For example, an electrical component other than the thermistor 63 may be connected to the second wiring 65b, such as a liquid leakage sensor that detects liquid leakage from the energy storage element 20, and the voltage applied via the second wiring 65b is lower than the rated voltage of the energy storage device 10. Furthermore, an electrical device connected by one or more electric wires as the second wiring 65b, which transmits a signal indicating the state of the energy storage device 10 to an external control device via the one or more electric wires and the second connector 86, may also be connected to the one or more electric wires.

Furthermore, the number of components, such as thermistors, that are provided in the power storage device 10 and electrically connected to the second connector 86 via the second wiring 65b is not limited to two. The number of such components may be one or more. Furthermore, different types of components (e.g., a thermistor and a liquid leakage sensor) may be electrically connected to the second connector 86 via the second wiring 65b.

Furthermore, while the first connector 85 and the second connector 86 each have multiple pins for connecting to external wiring, there are no particular limitations on the shape or type of the first connector 85 and the second connector 86. For example, the first connector 85 or the second connector 86 may have multiple pin holes into which multiple pins on the connector at the end of the external wiring are inserted.

Furthermore, the shape of the energy storage element 20 provided in the energy storage device 10 does not have to be rectangular. The shape of the energy storage element 20 may be, for example, circular, elliptical, oval, polygonal other than rectangular, or a shape that combines curved and straight lines in a plan view. In any case, the effects of the harness plate 50 according to this embodiment, such as improved safety, as described above, can be achieved.

In addition, in the above embodiment, the electrode terminals (positive terminal 22 and negative terminal 23) of the energy storage element 20 have bolt portions, and the electrode terminals of the energy storage element 20 and the bus bar 40 are connected by inserting the bolt portions into the through holes of the bus bar 40 and fastening nuts to the bolt portions. However, the electrode terminals of the energy storage element 20 may not have bolt portions, and the electrode terminals and the bus bar 40 may be connected (joined) by welding. Furthermore, the method of joining the detection terminal 80 to the electrode terminal or the bus bar 40 is not limited to fastening with nuts, and may also be joined by welding.

Furthermore, configurations constructed by any combination of the components included in the above embodiments and their variations are also included within the scope of the present invention.

The present invention can be realized not only as the energy storage device 10, but also as a wiring holding member (harness plate 50 in this embodiment) included in the energy storage device 10.

The present invention can be applied to energy storage devices equipped with energy storage elements such as lithium-ion secondary batteries.

REFERENCE SIGNS LIST 10 Electricity storage device 10A First electricity storage device 10B Second electricity storage device 10C Third electricity storage device 10D Fourth electricity storage device 10E Fifth electricity storage device 12, 13 Conductive member 12A First conductive member 12B Second conductive member 12C Third conductive member 20, 20A to 20K Electricity storage element 50 Harness plate 51 First restricting portion 52 Second restricting portion 54 Wall portion 56a First region 56b Second region 65a First wiring 65b Second wiring 85 First connector 85a, 86a Connection port 86 Second connector 100, 300 Lid body 105 Lower surface portion

Claims (7)

A storage element;
a first wiring electrically connected to the energy storage element;
a flat rectangular wiring holding member that holds the first wiring;
a first connector connected to the first wiring, the first connector being attached to the wiring holding member and allowing an external wiring to be attached and detached;
the wiring holding member has a restricting portion which is a claw-shaped portion or a protrusion-shaped portion, and the restricting portion holds the first wiring;
the first connector has a connection port arranged in a second direction intersecting a first direction in which the first connector is attached to the wiring holding member,
The restricting portion is located in the second direction of the connection port when viewed from the first direction.
Energy storage device. the first wiring is arranged to bypass a second region of the wiring holding member on the connection port side of the first connector,
The power storage device according to claim 1 . the wiring holding member has a wall portion erected along at least a part of the periphery of the second region;
The power storage device according to claim 2 . the restricting portion restricts the first wirings to positions within the first region where they do not overlap with each other in an arrangement direction of the energy storage elements and the wiring holding member.
The power storage device according to claim 1 . The first wiring is connected to an electrode terminal of the energy storage element or a bus bar connected to the energy storage element.
The electricity storage device according to any one of claims 1 to 4. Further, a second wiring which is a wiring for a lower voltage than the first wiring and is held by the wiring holding member is provided.
The electricity storage device according to any one of claims 1 to 5. Further, a second connector connected to the second wiring is attached to the wiring holding member.
The power storage device according to claim 6.