Power storage device

Abstract

To provide a power storage device which can reduce damage to a power storage stack even when an impact is applied to a protection panel for a vehicle bottom part due to interference with a road surface and so forth.SOLUTION: A power storage device comprises: a power storage stack which includes a plurality of power storage cells aligned in a predetermined direction; a binding member which binds the power storage stack by pressing the power storage stack in the predetermined direction; a housing case which houses the power storage stack by disposing the bound power storage stack on a bottom wall part; a cooler which is provided on the opposite side, of the bottom wall part, to the power storage stack and cools the power storage stack; a protection panel which is located below the cooler in top view of the power storage device and protects the cooler from interference with a road surface and so forth; and a sensor which is disposed between the protection panel and the bottom wall part, and detects pressure applied in a vertically upward direction. Between the power storage stack and the bottom wall part, the binding member extends in the predetermined direction. In top view of the power storage device, the sensor is located below the binding member.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to an electricity storage device. [Background technology]

[0002] As a conventional power storage device, Japanese Patent Application Laid-Open No. 2018-072296 (Patent Document 1) discloses a configuration in which an impact detection device is attached to the underside of a battery pack tray. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-072296 A Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, when the impact detection device (sensor) detects an impact, pressure is also applied to the bottom surface of the battery pack tray. If the battery pack tray is deformed by the pressure, the bottom surface of the battery pack (power storage stack) may be damaged.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and its purpose is to provide an energy storage device that can reduce damage to the energy storage stack even if an impact is applied to a protective panel (also called a "share panel") at the bottom of the vehicle due to road surface interference, etc. [Means for solving the problem]

[0006] The electric storage device according to the present disclosure includes an electric storage stack including a plurality of electric storage cells arranged in a predetermined direction, a restraining member that presses the electric storage stack in a predetermined direction to restrain the electric storage stack, a housing case having a bottom wall portion and housing the restrained electric storage stack by placing the electric storage stack restrained by the restraining member on the bottom wall portion, a cooler that is provided on the opposite side of the restrained electric storage stack with respect to the bottom wall portion and cools the electric storage stack, a protective panel that is located below the cooler in a top view of the electric storage device and protects the cooler from interference with the road surface or obstacles on the road surface, and a sensor that is installed between the protective panel and the bottom wall portion and detects pressure in a vertically upward direction. The restraining member extends in a predetermined direction between the electric storage stack and the bottom wall portion. The sensor is located below the restraining member in a top view of the electric storage device.

[0007] According to the above configuration, when the protective panel is deformed and hits the sensor, the impact force applied to the sensor is transmitted to the power storage stack via the restraining member. Therefore, the impact force applied to the power storage stack can be reduced compared to a configuration in which the impact force applied to the sensor is transmitted to the power storage stack without passing through the restraining member. Therefore, even if an impact is applied to the protective panel due to interference with the road surface or an obstacle on the road surface, damage to the power storage stack can be reduced. Furthermore, according to the above configuration, the detection result of the sensor enables the user to know that the protective panel has been deformed and that there is a possibility of damage to the power storage device.

[0008] Preferably, the cooler has an opening extending in a predetermined direction. The opening is located below the restraining member when viewed from above the power storage device. The sensor is installed in the opening. With the above configuration, it is possible to prevent an impact applied to the sensor from being transmitted to the cooler. Effect of the Invention

[0009] According to the present disclosure, even if an impact is applied to the protective panel due to interference with the road surface or an obstacle on the road surface, damage to the power storage stack can be reduced. [Brief description of the drawings]

[0010] [Figure 1] FIG. [Diagram 2] FIG. 2 is a cross-sectional view taken along line II-II of FIG. [Diagram 3] 10 is a cross-sectional view illustrating a state in which a share panel is deformed due to interference between a vehicle equipped with an electricity storage device and a road surface or an obstacle on the road surface. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the following description, the same members are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

[0012] Fig. 1 is an exploded perspective view of an electricity storage device according to the present embodiment. With reference to Fig. 1, an electricity storage device 100 according to the present embodiment will be described.

[0013] The power storage device 100 is mounted on a hybrid vehicle capable of running using at least one of the power of a motor and an engine, or on an electrically powered vehicle that runs using driving force obtained from electric energy.

[0014] The electricity storage device 100 includes a plurality of electricity storage stacks 10, a storage case 20, a cooler 30, an adhesive layer 40 (see FIG. 2), a shear panel (protective panel) 50, and a plurality of restraining members 70. The storage case 20 includes an upper case 21 and a lower case 22.

[0015] Each of the plurality of power storage stacks 10 includes a plurality of power storage cells 11 arranged side by side in an arrangement direction DR1. When the power storage device 100 is mounted on a vehicle, the arrangement direction DR1 is, for example, substantially parallel to the left-right direction of the vehicle. Spacers (not shown) are arranged between the power storage cells 11 adjacent to each other.

[0016] The power storage stacks 10 are arranged side by side in a cross direction DR2 (more specifically, a direction perpendicular to the arrangement direction DR1) that crosses the arrangement direction DR1. In the mounted state, the cross direction DR2 is, for example, substantially parallel to the front-rear direction of the vehicle.

[0017] Each of the power storage stacks 10 is fixed to the storage case 20 (more specifically, a bottom wall portion 23 described below) by an adhesive layer 40 (see FIG. 2). Each power storage stack 10 may be fixed to the storage case 20 by a bracket.

[0018] The storage cell 11 is, for example, a secondary battery such as a nickel-metal hydride battery or a lithium-ion battery. The single cell has, for example, a rectangular shape. The secondary battery may use a liquid electrolyte or a solid electrolyte. The storage cell may also be a unit capacitor configured to be capable of storing electricity.

[0019] Each of the multiple restraining members 70 presses a different one of the power storage stacks 10 in the arrangement direction DR1 to restrain the power storage stacks 10. Each of the restraining members 70 extends in the arrangement direction DR1 between the power storage stack 10 and the lower case 22 (more specifically, a bottom wall portion 23 described later).

[0020] The storage case 20 accommodates a plurality of power storage stacks 10 therein. The upper case 21 has a generally box-like shape that opens downward. The lower case 22 includes a bottom wall portion 23 and has a generally box-like shape that opens upward. The storage case 20 accommodates the power storage stack 10 restrained by the restraining members 70 by placing the restrained power storage stack 10 on the bottom wall portion 23.

[0021] The bottom wall portion 23 includes, for example, a mounting portion 24, a pair of bottom wall portions 25, and a pair of connection portions 26. The mounting portion 24 has a mounting surface 24a on which the electricity storage stack 10 is placed. The bottom wall portion 23 is provided such that the mounting portion 24 is located at a position higher than the bottom wall portions 25 as a whole.

[0022] The mounting surface 24a is divided into a plurality of partitioned regions R1 in the intersecting direction by the partitioning member 27. The power storage stack 10 is placed in each of the plurality of partitioned regions R1 divided by the partitioning member 27. More specifically, in each partitioned region R1, the mounting surface 24a has a first portion 241, a second portion 242, and a recess 243.

[0023] One side of the power storage stack 10 in the intersecting direction DR2 is placed on the first portion 241. The other side of the power storage stack 10 in the intersecting direction DR2 is placed on the second portion 242. The recess 243 is provided between the first portion 241 and the second portion 242. The recess 243 is provided so as to continue from one end to the other end of the mounting surface 24a in the arrangement direction DR1. Also, in each partition region R1, a low wall portion 25 is provided so as to surround the mounting surface 24a when viewed from above.

[0024] A pair of bottom wall portions 25 are provided at both ends of the bottom wall portion 23 in the arrangement direction DR1. The bottom wall portions 25 extend along the direction in which the plurality of power storage stacks 10 are arranged (cross direction DR2). The bottom wall portions 25 are located at a position lower in height than the mounting surface 24a. The height direction is a direction parallel to the direction in which the upper case 21 and the lower case 22 are arranged, and corresponds to the up-down direction.

[0025] The pair of connecting portions 26 connect the pair of bottom wall portions 25 and the mounting portion 24. The pair of connecting portions 26 are curved so that their height positions become lower toward the outside in the arrangement direction DR1.

[0026] The cooler 30 is a device for cooling the multiple power storage stacks 10. The cooler 30 is disposed outside the accommodation case 20. Specifically, the cooler 30 is disposed below the bottom wall portion 23 of the lower case 22. More specifically, the cooler 30 is provided on the opposite side of the bottom wall portion 23 to the restrained power storage stacks 10, and cools the power storage stacks 10. The cooler 30 is located between the bottom wall portion 23 and the share panel 50.

[0027] The cooler 30 is made of a metal material such as aluminum. The cooler 30 includes a plurality of cooling parts 32 and a holding frame part 34. The plurality of cooling parts 32 are provided in each partitioned region R1 so as to correspond to the first part 241 and the second part 242. The plurality of cooling parts 32 are in thermal contact with the back surface 24b of the part located on the opposite side to the first part 241 and the second part 242 via a heat conduction layer 60 (see FIG. 2).

[0028] The cooling sections 32 are arranged side by side in a direction parallel to the intersecting direction DR2. Each of the cooling sections 32 is arranged at a position facing the electricity storage stack 10 with the bottom wall section 23 in between. The cooling sections 32 are arranged so as to be in thermal contact with the back surface 24b (see FIG. 2) of the mounting section 24 located on the opposite side to the side on which the mounting surface 24a is located. This allows the cooling sections 32 to efficiently cool the mounting section 24, and therefore the electricity storage stack 10 placed on the mounting surface 24a.

[0029] The cooling section 32 is formed with a cooling flow passage 32a (see FIG. 2) through which a cooling medium (such as water) for cooling the electricity storage stack 10 flows.

[0030] The holding frame 34 holds each cooling section 32. The holding frame 34 is formed in a ring shape surrounding the cooling sections 32. In this embodiment, the holding frame 34 is formed in a substantially rectangular shape. Each cooling section 32 is connected to the holding frame 34 at both ends in the arrangement direction DR1.

[0031] The share panel 50 is disposed so as to cover the cooler 30 from below. The share panel 50 protects the cooler 30. More specifically, the share panel 50 is located below the cooler 30 when viewed from above the energy storage device 100, and protects the cooler 30 from interference with the road surface or obstacles on the road surface. The share panel 50 is made of a metal material.

[0032] Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1. As shown in Fig. 2, the bottom wall portion 23 (more specifically, the mounting portion 24) includes a bottom wall portion 2410 having a first portion 241, a bottom wall portion 2420 having a second portion 242, and a bottom wall portion 2430 that is continuous with the two bottom wall portions 2410, 2420 and protrudes from the bottom wall portions 2410, 2420 toward the share panel 50. The bottom wall portion 2430 has a recess 243.

[0033] The restraining member 70 extends in the arrangement direction DR1 (see FIG. 1 ) between the power storage stack 10 and the bottom wall portion 23. The restraining member 70 is located between the power storage stack 10 and the bottom wall portion 2430. In this example, the restraining member 70 is located on the recess 243 of the mounting portion 24.

[0034] The electricity storage device 100 further includes a piezoelectric sensor 80 that detects pressure. The piezoelectric sensor 80 is installed between the share panel 50 and the bottom wall portion 23, and detects pressure in the vertically upward direction. The piezoelectric sensor 80 is located below the restraining member 70 in a top view of the electricity storage device 100. In this example, the piezoelectric sensor 80 is attached to the surface of the bottom wall portion 2430 opposite to the recess 243 (a part of the back surface 24b).

[0035] The cooler 30 has an opening 39 extending in the arrangement direction DR1. The opening 39 is located below the restraining member 70 in a top view of the electricity storage device 100. A piezoelectric sensor 80 is installed in the opening 39. The cooler 30 has flange portions 321 and 322 facing each other. The flange portions 321 and 322 extend parallel to the bottom wall portion 23. The piezoelectric sensor 80 is installed between the flange portions 321 and 322.

[0036] Fig. 3 is a cross-sectional view showing a state in which the shared panel 50 is deformed due to interference between the vehicle equipped with the power storage device 100 and the road surface or an obstacle on the road surface. Fig. 3 is a cross-sectional view taken at the same position as Fig. 2.

[0037] 3, in this example, the shear panel 50 deforms in the direction of arrow A (upward), and the shear panel 50 collides with the piezoelectric sensor 80. When the shear panel 50 collides with the piezoelectric sensor 80, the piezoelectric sensor 80 transmits an impact force to an instrument located above the piezoelectric sensor 80. In this example, the restraining member 70 is located above the piezoelectric sensor 80.

[0038] Therefore, the impact force applied to the piezoelectric sensor 80 is transmitted to the power storage stack 10 via the restraint member 70. Therefore, the impact force applied to the power storage stack 10 can be reduced compared to a configuration in which the impact force applied to the piezoelectric sensor 80 is transmitted to the power storage stack 10 without passing through the restraint member 70. Therefore, according to the power storage device 100, even if an impact is applied to the share panel 50 due to road surface interference or the like, damage to the power storage stack 10 can be reduced.

[0039] Furthermore, the piezoelectric sensor 80 can detect deformation of the share panel 50. A vehicle controller (not shown) displays the detection result on a monitor or the like inside the vehicle, allowing a user or the like to know that the share panel 50 has been deformed and that there is a possibility that the power storage device 100 has been damaged.

[0040] As described above, the cooler 30 has the opening 39 extending in the arrangement direction DR1. The opening 39 is located below the restraining member 70 in a top view of the electricity storage device 100. The piezoelectric sensor 80 is installed inside the opening 39. With this configuration, it is possible to suppress the transmission of an impact applied to the piezoelectric sensor 80 to the cooler 30.

[0041] In particular, by positioning the piezoelectric sensor 80 in the vertical direction so that it is more susceptible to impacts caused by deformation of the share panel 50 than the cooler 30, the cooler 30 can be protected from interference with the road surface or obstacles on the road surface.

[0042] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is defined by the scope of the claims, and it is intended to include all modifications within the scope and meaning equivalent to the scope of the claims. [Explanation of symbols]

[0043] 10 storage stack, 11 storage cell, 20 storage case, 21 upper case, 22 lower case, 23, 2410, 2420, 2430 bottom wall portion, 24 mounting portion, 24a mounting surface, 24b back surface, 25 bottom wall portion, 26 connection portion, 27 partition member, 30 cooler, 32 cooling portion, 32a cooling flow path, 34 holding frame portion, 39 opening, 40 adhesive layer, 50 shear panel, 60 thermally conductive layer, 70 restraining member, 80 piezoelectric sensor, 100 storage device, 241 first portion, 242 second portion, 243 recess, 321, 322 flange portion, DR1 arrangement direction, DR2 cross direction, R1 partition area.

Claims

1. A power storage device, A storage stack including a plurality of storage cells arranged in a predetermined direction; a restraining member that presses the electricity storage stack in the predetermined direction to restrain the electricity storage stack; a storage case having a bottom wall portion, the storage stack being restrained by the restraining member being placed on the bottom wall portion to accommodate the restrained storage stack; a cooler that is provided on an opposite side of the bottom wall portion from the restrained electricity storage stack and that cools the electricity storage stack; a protective panel that is located below the cooler when viewed from above the power storage device and protects the cooler from interference with a road surface or an obstacle on the road surface; a sensor disposed between the protection panel and the bottom wall portion and configured to detect a pressure in a vertically upward direction; the restraint member extends in the predetermined direction between the power storage stack and the bottom wall portion, The sensor is located below the restraining member in a top view of the power storage device.

2. The cooler has an opening formed therein and extending in the predetermined direction, the opening is located below the restraining member in a top view of the power storage device, The power storage device according to claim 1 , wherein the sensor is disposed inside the opening.

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