JP2016031995A - Power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect expansion of a container of a storage battery.SOLUTION: When expansion of a container 11 of a power storage cell 2 progresses and a second end plate 3B moves in an X direction along a rod 64 on a coupling part 63 side, an elastic member 90 slides on the rod 64 together with a mounting member 42A to be brought into contact with a reflector 71. Thus, the elastic member 90 restricts the move of the second end plate 3B in the X direction and serves as a resistance member against the expansion between a first end plate 3A and the second end plate 3B.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a power storage device.

  There is a power storage device applied to a power storage system. The power storage device includes, for example, a lithium ion capacitor module. A lithium ion capacitor module is a type of assembled battery that is assembled by stacking a plurality of storage batteries in the thickness direction and electrically connecting them together. The storage battery has a sealed structure in which, for example, an electrode laminate in which positive electrodes, negative electrodes, and separators are alternately stacked in a container made of a laminate material such as an aluminum laminate film and an organic electrolyte containing lithium ions, for example.

JP 2010-161044 A

  Here, in the storage battery, the container may expand due to a gas that has vaporized the internal organic electrolyte due to aging or the like. And in the storage battery, there may be inconveniences such as a decrease in power storage performance due to gas. Therefore, it is desirable for the storage battery to recognize the possibility of such inconvenience in advance and take appropriate measures. However, the above-described conventional technology cannot detect the expansion of the storage battery container.

  In view of the above-described problems, an example of an embodiment aims to detect expansion of a storage battery container.

  The power storage device according to an example of the embodiment includes a substantially flat storage battery, a first plate, a second plate, a connecting member, an elastic member, and a detection unit. The first plate is positioned parallel to the first surface of the storage battery and holds the storage battery. A 2nd plate is located in parallel with respect to the 2nd surface side of the storage battery on the opposite side to the 1st surface side, and hold | maintains a storage battery. The connecting member connects the first plate and the second plate so that the second plate can move in a direction in which the space between the first plate and the second plate expands. The elastic member becomes resistant to the movement of the second plate in the expanding direction. The detection unit detects the movement of the second plate in the expanding direction.

  According to an example of the embodiment, the expansion of the storage battery container can be detected.

FIG. 1 is a perspective view illustrating an appearance of a power storage module according to the embodiment. FIG. 2 is a perspective view illustrating an appearance of the storage cell according to the embodiment. FIG. 3 is an explanatory diagram illustrating the storage cell of the embodiment. Drawing 4 is a top view showing an example of the 1st end plate of an embodiment. FIG. 5 is a plan view illustrating an example of the second end plate according to the embodiment. FIG. 6 is a schematic cross-sectional view illustrating the power storage device of the embodiment. FIG. 7 is a schematic exploded perspective view illustrating an example of the connecting member of the embodiment. FIG. 8 is a schematic cross-sectional view illustrating a storage cell expansion detection mechanism in the power storage device of the embodiment. FIG. 9 is a schematic view of the power storage device of the embodiment as viewed from the expansion detection mechanism side. FIG. 10 is a block diagram illustrating an example of the monitoring circuit according to the embodiment. FIG. 11 is a flowchart illustrating an example of a processing operation of the CPU related to the expansion notification process according to the embodiment. FIG. 12 is a schematic cross-sectional view showing a storage cell expansion detection mechanism in a modified power storage device. FIG. 13 is an explanatory diagram illustrating an example of the relationship between the cell internal pressure of the storage cell of the expansion detection mechanism and the expansion detection sensor output for each type of elastic member of the example.

  Hereinafter, a power storage module according to an example of an embodiment will be described with reference to the drawings. The following embodiments and modifications are merely examples and do not limit the disclosed technology. The following embodiments and modifications can be appropriately combined within a consistent range. In each embodiment and modification, each position such as “upper” and “lower” shown with reference to the drawings only indicates a relative position shown in each drawing, and does not indicate an absolute position. . Moreover, in each embodiment and modification, the same code | symbol is provided to the same component and description is abbreviate | omitted in the case of later mention.

[Embodiment]
(Configuration of power storage module of embodiment)
FIG. 1 is a perspective view illustrating an appearance of a power storage module according to the embodiment. The power storage module 1 shown in FIG. 1 includes a plurality of power storage cells 2, a first end plate 3 </ b> A, a second end plate 3 </ b> B, a connection plate 4, a plurality of brackets 5, and a connection member 6. The power storage module 1 is, for example, an electric double layer lithium ion capacitor module.

  As will be described later, the power storage module 1 includes a plurality of power storage cells 2 in which an electrode laminate in which a positive electrode and a negative electrode are stacked is sealed in a container made of a laminate material. In the power storage module 1, the flat surfaces are overlaid in a state where an adhesive is applied to the flat surface (cell main surface) of each power storage cell 2, and the power storage cells 2 are bonded together in a state where each flat surface is pressurized in the overlapping direction. Is formed. In addition, although the electrical storage module 1 illustrated the electrical storage module which mounted the 4 electrical storage cell 2, for example, it is not limited to four, What is necessary is just two or more.

  The bracket 5 includes two brackets having a substantially U-shaped cross section, the first bracket 5A for holding the cell assembly from one side on the short side, and the cell assembly from the other side on the short side. It has the 2nd bracket 5B to hold | maintain. The cell aggregate is an aggregate in which the first end plate 3A, the plurality of power storage cells 2 and the second end plate 3B are overlapped. The first bracket 5A and the second bracket 5B hold the cell assembly from both sides using the first end plate 3A and the second end plate 3B.

(Electric storage cell of embodiment)
FIG. 2 is a perspective view illustrating an appearance of the storage cell according to the embodiment. FIG. 3 is an explanatory diagram illustrating the storage cell of the embodiment. The storage cell 2 shown in FIG. 2 is, for example, an electric double layer lithium ion capacitor cell. The electrical storage cell 2 includes a container 11 made of a laminate material that houses an electrode laminate (not shown), and an electrode terminal 12. The electrode laminate is configured by laminating a positive electrode, a negative electrode, and a separator (not shown). The power generation element is one unit, and a plurality of units of power generation elements are stacked.

  The positive electrode has a structure in which, for example, a positive electrode made of a material capable of reversibly supporting lithium ions is formed on a positive electrode current collector. The positive electrode current collector is a member for collecting current while supporting the positive electrode, and is formed using a conductive metal plate such as aluminum. The positive electrode current collector is formed in a rectangular shape in plan view, and has a structure in which the tab 13A protrudes from one of the four sides. The tab 13A is connected to a positive electrode terminal 12A such as aluminum among the electrode terminals 12.

  The negative electrode has a structure in which, for example, a negative electrode made of a material capable of reversibly supporting lithium ions is formed on a negative electrode current collector. The negative electrode current collector is a member for collecting current while supporting the negative electrode, and is formed using a conductive metal plate such as copper, for example. The negative electrode current collector is formed in a rectangular shape in plan view, and has a structure in which the tab 13B protrudes from one of the four sides. The tab 13B is connected to the negative electrode terminal 12B such as copper among the electrode terminals 12. Moreover, the negative electrode current collector has a lithium sticking portion (not shown) to which a pre-doping lithium metal foil is stuck. The lithium metal foil dissolves and disappears when pre-doping is completed.

  The container 11 is a rectangular soft container made of an aluminum laminated film material obtained by laminating an aluminum foil with a resin film, for example. Furthermore, the container 11 has a structure in which the electrode stack is sealed together with an organic electrolyte containing lithium ions, for example. Since the container 11 seals the electrode laminate and the organic electrolyte, the surface of the container 11 has a shape in which the shape of the electrode laminate is raised near the center. The raised surface portion of the container 11 is referred to as a cell main surface 14.

  In addition, as a layer structure of the aluminum laminate film material, PP (Polypropylene) layer, PPa (polyphthalamide) layer, AL (aluminum) layer, nylon layer, PET (from the inner layer to the outer layer of the storage cell 2 PolyEthyleneTerephthalate) layer. The layer structure of the aluminum laminate film material is, for example, from the inner layer to the outer layer of the storage cell 2 in the order of a PPa (polyphthalamide) layer, an AL (aluminum) layer, a nylon layer, and a PET (PolyEthyleneTerephthalate) layer. May be. In the electricity storage cell 2, the organic electrolyte in the container 11 is vaporized due to secular change or the like to generate gas, and the container 11 may expand.

  When the electrode stack is accommodated in the container 11, the storage cell 2 has a structure in which the positive electrode terminal 12 </ b> A and the negative electrode terminal 12 </ b> B protrude from one side of the four rectangular sides. The positive electrode terminal 12A is made of, for example, an aluminum material, and has a structure in which a distal end portion thereof is bent at a right angle toward one cell main surface 14 as shown in FIGS. The negative electrode terminal 12B is made of, for example, a copper material, and has a structure in which a tip portion thereof is bent at a right angle toward the other cell main surface 14 as shown in FIGS.

  In the power storage module 1, for example, when a plurality of power storage cells 2 are connected in series, the front end portion of the positive electrode terminal 12 </ b> A of the power storage cell 2 and the front end portion of the negative electrode terminal 12 </ b> B of the opposite power storage cell 2 in surface contact with the power storage cell 2 Are electrically connected by welding or the like. Further, in the power storage module 1, the tip portion of the negative electrode terminal 12B of the power storage cell 2 and the tip portion of the positive electrode terminal 12A of the opposite power storage cell 2 are electrically connected by welding or the like.

  In addition, when the power storage module 1 connects, for example, a plurality of power storage cells 2 in parallel, the front end portion of the positive electrode terminal 12 </ b> A of the power storage cell 2 and the front end of the positive electrode terminal 12 </ b> A of the opposite power storage cell 2 in surface contact with the power storage cell 2 The part is electrically connected by welding or the like. Furthermore, the power storage module 1 electrically connects the tip portion of the negative electrode terminal 12B of the power storage cell 2 and the tip portion of the negative electrode terminal 12B of the opposite power storage cell 2 by welding or the like.

(First end plate of the embodiment)
Drawing 4 is a top view showing an example of the 1st end plate of an embodiment. The first end plate 3A shown in FIG. 4 is formed of a sheet metal member having a rectangular shape in plan view, and has a concave first holding portion 31 on the back surface thereof. The 1st holding | maintenance part 31 is a surface part which surface-contacts with the cell main surface 14 of the electrical storage cell 2, and is a structure which can be accommodated so that the cell main surface 14 which carried out surface contact may not shift. Of the four sides of the first end plate 3A, a first attachment portion 32 connected to the connecting member 6 is attached to one side thereof by fastening a fastening member 67 such as a screw. The first attachment portion 32 has a screw hole 33 penetrating the surface portion.

(Second end plate of the embodiment)
FIG. 5 is a plan view illustrating an example of the second end plate according to the embodiment. The second end plate 3B shown in FIG. 5 is formed of a sheet metal member having a rectangular shape in plan view, and has a concave second holding portion 41 on the back surface thereof. The 2nd holding | maintenance part 41 is a surface part which surface-contacts with the cell main surface 14 of the electrical storage cell 2, and is a structure which can be accommodated so that the cell main surface 14 in surface contact may not be displaced. The second end plate 3B has a structure in which the second attachment portion 42 protrudes from one of the four sides. Further, the second mounting portion 42 is formed with a guide hole 43 that protrudes in the direction of the back surface of the second end plate 3B and penetrates the surface portion. The second attachment portion 42 is attached to one side of the four sides of the end plate 3B by fastening a fastening member 68 such as a screw.

(General cross section of power storage device)
FIG. 6 is a schematic cross-sectional view illustrating the power storage device of the embodiment. The power storage device 10 illustrated in FIG. 6 includes a power storage case 100 </ b> A that houses the power storage module 1. A monitoring circuit 100 is provided on the top of the electricity storage case 100A. The monitoring circuit 100 is a circuit that monitors the entire power storage module 1. Furthermore, the monitoring circuit 100 has an interface (not shown) connected to an external circuit.

(Schematic configuration of expansion detection mechanism)
FIG. 7 is a schematic exploded perspective view illustrating an example of the connecting member of the embodiment. FIG. 8 is a schematic cross-sectional view illustrating a storage cell expansion detection mechanism in the power storage device of the embodiment. FIG. 9 is a schematic view of the power storage device of the embodiment as viewed from the expansion detection mechanism side. The connecting member 6 shown in FIG. 7 includes a main body 61 and a connecting portion 63 provided at one end of the main body 61. The main body 61 has a structure in which the inside is formed of a metal material and the surface of the metal material is covered with an insulating material. The connecting member 6 is connected to the mounting member 32A of the first mounting portion 32 on the back surface of the first end plate 3A at the end on which the connecting portion 63 is not provided, and the first surface is connected to the first connecting portion 32A. A female screw 62A is formed.

  The connecting portion 63 has a structure in which a rod 64 fitted into the guide hole 43 of the second attachment portion 42 on the back surface of the second end plate 3B protrudes from the longitudinal direction of the main body 61. A second female screw 64 </ b> A is formed on the end surface of the rod 64. The reflection plate 71 is, for example, a thin plate-like metal that reflects light. The reflection plate 71 reflects light and causes the expansion detection sensor 80 described later to detect the reflected light. The reflecting plate 71 has a structure in which a hole 71a is formed in a substantially center of a substantially disk shape. The second female screw 64A of the rod 64 and the hole 71a of the reflecting plate 71 are overlapped, and the second male screw 66 is screwed into the second female screw 64A from the hole 71a, whereby the reflecting plate is connected to the connecting portion 63. 71 is fixed, and the connecting portion 63 is connected to the second end plate 3B.

  The expansion detection mechanism 7 shown in FIG. 8 holds the plurality of power storage cells 2 with the first end plate 3A and the second end plate 3B. The expansion detection mechanism 7 holds the plurality of power storage cells 2 and then connects the first end plate 3A and the second end plate 3B to the expansion detection sensor 80 provided on the substrate 60 therebetween. A reflection plate 71 facing the expansion detection sensor 80 is arranged and connected by the connecting member 6. The expansion detection sensor 80 is a photo sensor, a distance sensor, a strain sensor, or the like. Further, the expansion detection mechanism 7 connects the connecting member 6 between the first end plate 3A and the second end plate 3B, and then uses the expansion detection sensor 80 and the reflection plate 71 to detect the container 11 of the storage cell 2. It is a mechanism for detecting expansion.

  The structure for connecting the first end plate 3A to the connecting member 6 is as follows. That is, the screw hole 33 of the first mounting portion 32 on the back surface of the first end plate 3A and the first female screw 62A on one end side of the connecting member 6 are overlapped to form the screw hole of the first end plate 3A. The first male screw 65 is screwed from 33 to the first female screw 62A. The first connecting part 62 of the connecting member 6 is connected to the first end plate 3A.

  The structure for connecting the second end plate 3B to the connecting member 6 is as follows. That is, an elastic member 90 such as an elastomer, rubber, or foam is disposed on at least a part of the inner periphery of the guide hole 43 of the second mounting portion 42 on the second end plate 3B side. The elastic member 90 may have a convex shape that fits into a concave portion provided on the inner periphery of the guide hole 43. Further, the elastic member 90 may have insulating properties. Then, the rod 64 of the connecting portion 63 is fitted into the inner periphery of the guide hole 43 together with the elastic member 90, the second female screw 64A of the rod 64 and the hole 71a of the reflecting plate 71 are overlapped, and the second 71 through the hole 71a. The second male screw 66 is screwed into the female screw 64A. And the connection part 63 of the connection member 6 is connected with the 2nd end plate 3B. Therefore, the second end plate 3 </ b> B is movable in the X direction along the rod 64 of the connecting portion 63.

  As shown in FIG. 8, the second end plate 3B is in a state where the container 11 of the storage cell 2 inside the storage module 1 is not expanded in the normal state. In this state, the portion 42 and the attachment surface on the connecting portion 63 side are in contact with each other. Furthermore, the distance between the attachment member 42A of the second attachment portion 42 and the reflection plate 71 is L1. Further, the distance between the expansion detection sensor 80 disposed on the substrate 60 provided on the mounting member 42A and the reflecting plate 71 is L2.

  The second end plate 3B is connected to the first end plate 3A and the second end along the rod 64 on the connecting portion 63 side according to the expansion of the container 11 due to the generation of gas in the storage cell 2 inside the storage module 1. It moves in the X direction to expand the opening between the plate 3B. At this time, the attachment member 42A of the second attachment portion 42 slides along the rod 64 in the X direction together with the elastic member 90, and the distance between the attachment member 42A and the reflection plate 71 becomes shorter than L1, and the expansion detection sensor. The distance between 80 and the reflecting plate 71 is shorter than L2.

  When the expansion of the container 11 of the electricity storage cell 2 proceeds and the second end plate 3B moves in the X direction along the rod 64 on the connecting portion 63 side, the elastic member 90 is mounted on the rod 64 on the mounting member. It slides with 42A and contacts the reflector 71. Therefore, the elastic member 90 regulates the movement of the second end plate 3B in the X direction, and is a resistance member against the expansion between the first end plate 3A and the second end plate 3B. Become.

  Thus, the elastic member 90 becomes resistance to the movement of the second end plate 3B in the X direction. For this reason, by changing the material of the elastic member 90 and adjusting the elastic coefficient according to the expansion characteristics of the container 11 of the storage cell 2, the X direction of the second end plate 3B is changed for each type of the storage cell 2. Can be adjusted appropriately. That is, the elastic member 90 is an adjustment mechanism that adjusts the relationship between the gas detection amount and the amount of movement of the second end plate 3B in the X direction.

  In FIG. 8, the elastic member 90 is disposed on at least a part of the inner periphery of the guide hole 43 of the mounting portion 42, and has a length that does not reach the reflection plate 71 along the rod 64 of the connecting member 6. . However, not limited to this, the elastic member 90 may have a length reaching the reflection plate 71 even when the container 11 of the storage cell 2 is not expanded. Further, the elastic member 90 may be disposed over the entire inner periphery of the guide hole 43 of the attachment portion 42. Further, the elastic member 90 may be disposed not on the inner periphery of the guide hole 43 of the mounting portion 42 but on at least a part of the rod 64 or over the entire periphery. The elastic member 90 is fixed so that the attachment position does not move. Further, the elastic member 90 moves the second end plate 3B between the first end plate 3A and the second end plate 3B on the axis where the second end plate 3B moves and expands. It may be provided at any position as long as it can resist.

(Monitoring circuit of embodiment)
FIG. 10 is a block diagram illustrating an example of the monitoring circuit according to the embodiment. A monitoring circuit 100 illustrated in FIG. 10 includes an alarm output unit 101 and a CPU 102. The CPU 102 controls the entire monitoring circuit 100. For example, when the expansion detection sensor 80 is a photosensor, the CPU 102 measures the light reception voltage of the reflected light reflected by the reflection plate 71, and based on the measured light reception voltage, the container 11 of the power storage cell 2 in the power storage module 1. The presence or absence of expansion is determined. When it is determined that the container 11 has expanded, the CPU 102 outputs an alarm for detecting the expansion of the container 11.

(Processing of CPU related to expansion notification processing)
FIG. 11 is a flowchart illustrating an example of a processing operation of the CPU related to the expansion notification process according to the embodiment. First, the CPU 102 determines whether or not the output of the received light voltage of the reflected light measured by the expansion detection sensor 80 has exceeded a predetermined threshold (step S11). CPU102 determines with the expansion | swelling detection of the container 11 of the electrical storage cell 2 in the electrical storage module 1 (step S12), when the output of a received light voltage exceeds a predetermined threshold value (step S11 affirmation). After determining that the expansion of the container 11 has been detected, the CPU 102 outputs an alarm for detecting the expansion of the container 11 of the storage cell 2 through the alarm output unit 101 (step S13), and ends the processing operation illustrated in FIG. As a result, the CPU 102 can notify the external device of the expansion of the container 11 of the storage cell 2, for example. On the other hand, when the output of the light reception voltage of the reflected light measured by the expansion detection sensor 80 does not exceed the predetermined threshold (No at Step S11), the CPU 102 ends the processing operation illustrated in FIG.

  The CPU 102 that executes the expansion notification process shown in FIG. 11 determines that the expansion of the container 11 has been detected and outputs an alarm when the output of the light reception voltage of the reflected light reflected by the reflection plate 71 by the expansion detection sensor 80 exceeds a predetermined threshold. Is output. As a result, the CPU 102 can notify, for example, an external device of the expansion of the container of the storage cell 2.

  In the above-described embodiment, the expansion detection mechanism 7 is applied to the power storage module 1 configured by stacking a plurality of power storage cells 2, but gasification of an internal organic electrolysis liquid or the like, Any storage battery whose container expands due to a factor may be applied to a single storage battery. That is, the said embodiment is not restricted to an electric double layer lithium ion capacitor module.

(Variant)
FIG. 12 is a schematic cross-sectional view showing a storage cell expansion detection mechanism in a modified power storage device. In the embodiment, in the expansion detection mechanism 7, the elastic member 90 is fixedly disposed on at least a part of the inner periphery of the guide hole 43 of the second attachment portion 42 on the second end plate 3B side. However, as shown in FIG. 12, the modified expansion detection mechanism 7a includes an attachment member 32A of the first attachment portion 32 and an attachment member 42A of the second attachment portion 42 instead of the elastic member 90 of the embodiment. Between them, a spring 90a may be provided. Alternatively, the modified expansion detection mechanism 7a may be provided with a spring 90b between the attachment member 42A of the second attachment portion 42 and the reflection plate 71 instead of the elastic member 90 of the embodiment. The spring 90a resists the expansion between the first end plate 3A and the second end plate 3B with a restoring force against the extension of the spring. Further, the spring 90b resists the expansion between the first end plate 3A and the second end plate 3B by the restoring force against the compression of the spring. Alternatively, the modified expansion detection mechanism 7a may include both the spring 90a and the spring 90b.

(Effect by embodiment)
In the power storage module 1, the first end plate 3 </ b> A and the second end plate 3 </ b> B are connected by the connecting member 6, and the second end plate 3 </ b> B is connected to the rod 64 according to the expansion of the container 11 of the power storage cell 2. Along the X direction. Then, according to the expansion of the container 11 of the storage cell 2, the attachment member 42 </ b> A of the second attachment portion 42 slides along the rod 64 in the X direction together with the elastic member 90. Then, the elastic member 90 provided in any part of the axis of the rod 64 in the X direction moves the mounting member 42A of the second mounting portion 42 of the second end plate 3B in the X direction along the rod 64. At this time, the movement of the mounting member 42A is restricted, or the movement of the mounting member 42A becomes resistance.

  Depending on the type of power storage cell 2 of the power storage module 1, the number of stacked power storage cells 2, etc., the amount of gas generated depends on the elapsed time, usage environment, etc., and the amount of gas generated that needs to be handled is also different. The amount of movement of the second end plate 3B in the X direction is also different. However, in the embodiment, since the amount of movement of the second end plate 3B in the X direction is regulated using the elastic member 90, the elastic member according to the type of the power storage module 1 or the power storage cell 2 having a different elastic coefficient. 90 is used. Thereby, the embodiment can easily adjust the amount of movement of the second end plate 3B in the X direction.

  In the conventional technology that does not use the elastic member 90, the rigidity of the expansion detection mechanism including the first end plate 3A, the second end plate 3B, the connecting member, and the like varies depending on the type of the power storage module 1 or the power storage cell 2. . Thereby, the prior art adjusts the amount of movement of the second end plate 3B in the X direction. Compared with the prior art, the embodiment adjusts the amount of movement of the second end plate 3B in the X direction by using the elastic member 90 having an appropriate elastic coefficient. For this reason, the embodiment adjusts the amount of movement of the second end plate 3B in the X direction easily and precisely without preparing an expansion detection mechanism having different rigidity depending on the type of the power storage module 1 or the power storage cell 2. Come out. In the embodiment, the production of the power storage module 1 and the power storage device 10 having the expansion detection mechanism 7 can be made more efficient, and the cost can be reduced.

(An example of the relationship between the cell internal pressure of the storage cell and the expansion detection sensor output for each type of elastic member)
FIG. 13 is an explanatory diagram illustrating an example of the relationship between the cell internal pressure of the storage cell of the expansion detection mechanism and the expansion detection sensor output for each type of elastic member of the example. The above embodiment adjusts the relationship between the internal pressure of the power storage cell 2 and the deformation amount of the power storage module 1 in consideration of the expansion detection of the power storage cell 2 in consideration of the internal pressure of the power storage cell 2 that has reached the expansion that needs to be dealt with. In the example, the relationship between the cell internal pressure of the storage cell of the expansion detection mechanism and the output of the expansion detection sensor was verified for several types of elastic members 90 of the expansion detection mechanism 7 in the embodiment. That is, the expansion detection sensor 80 that is a photosensor approaches the reflecting plate 71 side due to the deformation of the second end plate 3B accompanying the increase in the internal pressure of the storage cell 2. Then, by comparing using several kinds of materials disposed between the expansion detection sensor 80 and the reflection plate 71, the elastic member 90 has a sliding resistance when the expansion detection sensor 80 approaches the reflection plate 71. Became variable.

  In FIG. 13, the internal pressure of the storage cell is taken on the X axis (horizontal axis), and the output voltage of the expansion detection sensor is taken on the Y axis (vertical axis). As shown in FIG. 13, (1) compared to the case without an elastic member, (2) the elastic member A, (3) the elastic member B, and (4) the elastic member C are all used. The relationship between the internal pressure of the cell 2 and the output of the expansion detection sensor 80 changed. That is, by using an elastic member having a larger elastic coefficient (harder) as the elastic member 90, each of the large elastic coefficients in the order of (2) elastic member A <(3) elastic member B <(4) elastic member C. The curve of the elastic material is as shown in FIG. That is, if the internal pressure of the same storage cell 2 is the output of the expansion detection sensor 80 is generally large, and if the output is the same expansion detection sensor 80, the internal pressure of the storage cell 2 is generally high. In this way, by changing the material of the elastic member 90, the output of the expansion detection sensor 80 corresponding to the internal pressure of each power storage cell 2, which differs depending on the type of the power storage module 1 or the power storage cell 2, can be easily adjusted. .

  The power storage devices 10 and 10a including the expansion detection mechanisms 7 and 7a and the power storage modules 1 and 1a according to the embodiments and the modifications described above are merely examples. That is, a power storage module configured by appropriately combining and substituting the units included in the power storage devices 10 and 10a and the power storage modules 1 and 1a including the expansion detection mechanisms 7 and 7a according to the embodiment and the modification is also related to the disclosed technology. Included in power storage module.

DESCRIPTION OF SYMBOLS 1, 1a Power storage module 2 Power storage cell 3A, 3B End plate 4 Connection plate 5, 5A, 5B Bracket 6 Connection member 7, 7a Expansion detection mechanism 10, 10a Power storage device 31, 41 Holding part 32A, 42A Attachment member 32, 42 Attachment Part 71 Reflecting plate 80 Expansion detection sensor 90 Elastic member 90a, 90b Spring

Claims (4)

A substantially flat storage battery;
A first plate for holding the storage battery in parallel with the first surface of the storage battery;
A second plate for holding the storage battery in parallel with the second surface side of the storage battery opposite to the first surface side;
A connecting member that connects the first plate and the second plate so that the second plate can move in a direction in which the space between the first plate and the second plate expands;
An elastic member that resists movement of the second plate in the expanding direction;
A power storage device comprising: a detection unit configured to detect movement of the second plate in the expanding direction. Having a plurality of the storage batteries,
The first plate is formed by laminating a plurality of the storage batteries, facing a substantially flat surface of the first storage battery arranged on one end side in the stacking direction,
2. The power storage device according to claim 1, wherein the second plate faces a substantially flat surface of a second storage battery disposed on the other end side in the stacking direction.   The power storage device according to claim 1, wherein the elastic member has an elastic coefficient that varies depending on an expansion amount that varies depending on a type of the storage battery.   The power storage device according to claim 1, wherein the elastic member is an elastomer.

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