JP6812651B2 - Power storage device - Google Patents

Description

The techniques disclosed herein relate to power storage devices.

In the power storage device, excessive heat is generated inside the case due to overcharging or the like, the electrolytic solution is decomposed, and the internal pressure rises, which may cause an abnormality. Therefore, the power storage device is required to have a structure that can ensure safety at the time of overcharging or the like.

In Patent Document 1, a short-circuit tab connected to the first electrode terminal (referred to as an energizing plate in the present specification) and a variable plate connected to the second electrode terminal (referred to as an inversion plate in the present specification). A power storage device comprising the above is disclosed. In this power storage device, when the internal pressure exceeds a predetermined value due to overcharging, the variable plate is inverted toward the short-circuit tab side and comes into contact with the short-circuit tab. By forcibly short-circuiting the first electrode terminal and the second electrode terminal in this way, overcharging of the power storage device is suppressed.

Japanese Unexamined Patent Publication No. 2012-119303

In the power storage device of Patent Document 1, when the variable plate is inverted toward the short-circuit tab side and comes into contact with the short-circuit tab due to an increase in internal pressure, an impact force acts on the variable plate from the short-circuit tab. Therefore, the short-circuit tab may be deformed depending on the magnitude of the impact force and the strength of the short-circuit tab, and the short-circuit state may not be maintained due to poor contact between the short-circuit tab and the variable plate. The present specification discloses a power storage device capable of suitably maintaining contact (that is, a short-circuit state) between the reversing plate and the energizing plate when the reversing plate is inverted due to an increase in internal pressure.

The power storage device disclosed in the present specification includes a case, an electrode assembly housed in the case, a first electrode terminal and a second electrode terminal attached to the case and electrically connected to the electrode assembly, and a case. A short-circuit device provided in the above, which switches between an insulated state in which the first electrode terminal and the second electrode terminal are insulated and a short-circuited state in which the first electrode terminal and the second electrode terminal are short-circuited. I have. The case has a first insertion hole and a second insertion hole that communicate the inside and the outside of the case. The first electrode terminal is attached to the first insertion hole and is electrically insulated from the case. The second electrode terminal is electrically connected to the case. The short-circuit device is arranged on the outside of the case, is electrically connected to the first electrode terminal, and is electrically connected to the case with an energizing plate that covers at least a part of the second insertion hole, and is attached to the second insertion hole. Insulates the case, the current-carrying plate, and the first electrode terminal from the reversing plate that closes the second insertion hole, and opens at least a part of the overlapping portion of the second insertion hole and the current-carrying plate in a plan view. It is equipped with an insulating member. The reversing plate is electrically insulated apart from the current-carrying plate in the insulated state, while is in contact with the current-carrying plate and electrically connected in the short-circuited state. The energizing plate has a high-rigidity portion having a higher rigidity than the other portions in at least a part of the portion overlapping the reversing plate in a plan view.

In the above power storage device, the energizing plate constituting the short-circuit device has a high-rigidity portion having a higher rigidity than the other portions at least a part of the portion overlapping the reversing plate in a plan view. Therefore, when the short-circuit device is operated to change from the insulated state to the short-circuited state (that is, the reversing plate is inverted), the impact force acting on the energizing plate can be received even in the high-rigidity portion. Therefore, the deformation of the energizing plate can be suppressed, and the contact between the reversing plate and the energizing plate in the short-circuited state can be preferably maintained.

The cross-sectional view of the power storage device of Example 1. FIG. 5 is a cross-sectional view (insulated state) showing a configuration of a short-circuit device of the power storage device according to the first embodiment. The plan view which shows the structure of the short-circuit device of the power storage device of Example 1. FIG. FIG. 5 is a cross-sectional view (short-circuit state) showing a configuration of a short-circuit device of the power storage device of the first embodiment. FIG. 5 is a cross-sectional view (insulated state) showing a configuration of a short-circuit device of the power storage device according to the second embodiment. The plan view which shows the structure of the short-circuit device of the power storage device of Example 2. FIG. FIG. 5 is a cross-sectional view (short-circuit state) showing a configuration of a short-circuit device of the power storage device according to the second embodiment. FIG. 5 is a cross-sectional view showing a configuration of a short-circuit device of the power storage device according to the third embodiment. FIG. 5 is a cross-sectional view showing a configuration of a short-circuit device of the power storage device according to the fourth embodiment.

The main features of the examples described below are listed. It should be noted that the technical elements described below are independent technical elements and exhibit technical usefulness alone or in various combinations, and are limited to the combinations described in the claims at the time of filing. It's not a thing.

(Characteristic 1) In the power storage device disclosed in the present specification, the energizing plate may cover the entire second insertion hole in a plan view, while at least having a hole in a range including the center of the reversing plate. Further, the outer peripheral edge of the hole may be located inside the outer peripheral edge of the second insertion hole. According to such a configuration, when the reversing plate is inverted, the reversing plate can be configured to come into contact with the energizing plate at the peripheral edge of the hole formed in the energizing plate. Therefore, the contact area between the reversing plate and the energizing plate in the short-circuited state can be increased, and the contact resistance between the two can be reduced.

(Feature 2) In the power storage device disclosed in the present specification, the high-rigidity portion may be one or a plurality of ribs. According to such a configuration, the surface area can be increased by the amount of the ribs, and the heat generated by the current flowing in the short-circuited state can be dissipated.

(Feature 3) In the power storage device disclosed in the present specification, the rib may extend in the radial direction of the reversing plate. According to such a configuration, the strength of the energizing plate with respect to the contact of the reversing plate can be suitably increased.

(Feature 4) In the power storage device disclosed in the present specification, a part of the rib may be located in a range including the outside of the outer peripheral edge of the reversing plate in a plan view. According to such a configuration, the deformation of the energizing plate due to the contact of the reversing plate can be further suppressed.

(Feature 5) In the power storage device disclosed in the present specification, the high-rigidity portion may be a portion where the dislocation density is increased by work hardening. With such a configuration, the strength of the energizing plate against the contact of the reversing plate can be increased.

(Feature 6) In the power storage device disclosed in the present specification, the high-rigidity portion may be a portion in which a reinforcing plate is joined to an energizing plate. With such a configuration, the strength of the energizing plate against the contact of the reversing plate can be increased.

(Characteristic 7) In the power storage device disclosed in the present specification, the high-rigidity portion may be formed only in the portion where the reversing plate comes into contact with the energizing plate in the short-circuited state. According to such a configuration, space saving and material cost can be reduced.

Hereinafter, the power storage device 100 of the first embodiment will be described. As shown in FIG. 1, the power storage device 100 includes a case 1, an electrode assembly 3 housed in the case 1, and first electrode terminals 5 and second electrode terminals 7 attached to the case 1. .. The electrode assembly 3, the first electrode terminal 5, and the second electrode terminal 7 are electrically connected to each other. Further, the power storage device 100 includes a short-circuit device 10 provided in the case 1. The electrolytic solution is injected into the inside of the case 1, and the electrode assembly 3 is immersed in the electrolytic solution.

The case 1 is made of metal and is a box-shaped member having a substantially rectangular parallelepiped shape. The case 1 includes a main body 111 and a lid portion 112 fixed to the main body 111. The lid 112 covers the upper part of the main body 111. The lid portion 112 is formed with a first insertion hole 81, a second insertion hole 82, and a third insertion hole 83. The first electrode terminal 5 communicates with the inside and outside of the case 1 through the first insertion hole 81. The second electrode terminal 7 communicates with the inside and outside of the case 1 through the third insertion hole 83. A seal member 61 is arranged between the first electrode terminal 5 and the lid portion 112. The seal member 61 goes around the outer peripheral surface of the first electrode terminal 5. The seal member 61 is in contact with the lower surface of the lid portion 112 of the case 1, the inner peripheral surface of the first insertion hole 81, and the outer peripheral surface of the first electrode terminal 5, thereby allowing the inside and outside of the first insertion hole 81 to be in contact with each other. It is sealed. The sealing member 61 is made of a material having insulating properties and electrolytic solution resistance (perfluoroalkoxy alkane (PFA) in this embodiment). The first electrode terminal 5 is electrically insulated from the case 1 by a sealing member 61. Further, the second electrode terminal 7 is electrically connected to the case 1. In this embodiment, the first electrode terminal 5 is a negative electrode terminal and the second electrode terminal 7 is a positive electrode terminal. The material of the sealing member 61 is not limited to this, and may be, for example, polytetrafluoroethylene (PTFE), polypropylene (PP), or the like.

The electrode assembly 3 includes a positive electrode sheet, a negative electrode sheet, and a separator arranged between the positive electrode sheet and the negative electrode sheet. The electrode assembly 3 is configured by laminating a plurality of positive electrode sheets, a plurality of negative electrode sheets, and a plurality of separators. The positive electrode sheet and the negative electrode sheet include a current collecting member and an active material layer formed on the current collecting member. As the current collector member, the one used for the positive electrode sheet is, for example, aluminum foil, and the one used for the negative electrode sheet is, for example, copper foil. Further, the electrode assembly 3 includes a positive electrode current collecting tab 51 provided for each positive electrode sheet and a negative electrode current collecting tab 52 provided for each negative electrode sheet. The positive electrode current collecting tab 51 is formed at the upper end of the positive electrode sheet. The negative electrode current collecting tab 52 is formed at the upper end of the negative electrode sheet. The positive electrode current collecting tab 51 and the negative electrode current collecting tab 52 project upward from the electrode assembly 3. The plurality of positive electrode current collecting tabs 51 are grouped together and fixed to the positive electrode lead 53. The plurality of negative electrode current collecting tabs 52 are grouped together and fixed to the negative electrode leads 54.

The positive electrode lead 53 is connected to the positive electrode current collecting tab 51 and the second electrode terminal 7. The positive electrode current collecting tab 51 and the second electrode terminal 7 are electrically connected via the positive electrode lead 53. The negative electrode lead 54 is connected to the negative electrode current collecting tab 52 and the first electrode terminal 5. The negative electrode current collecting tab 52 and the first electrode terminal 5 are electrically connected via the negative electrode lead 54.

Next, the short-circuit device 10 will be described. As shown in FIG. 2, the short-circuit device 10 is provided on the lid 112 of the case 1. The short-circuit device 10 is in an insulated state in which the first electrode terminal 5 and the second electrode terminal 7 are insulated, and a short-circuited state in which the first electrode terminal 5 and the second electrode terminal 7 are short-circuited. Switch. The short-circuit device 10 includes a current-carrying plate 20, an inversion plate 30, and an insulating member 62.

The reversing plate 30 is a conductive diaphragm that is circular in a plan view, and is convex downward in an insulated state. The reversing plate 30 is made of, for example, aluminum or an aluminum-based alloy. The reversing plate 30 is electrically connected to the lid portion 112 of the case 1. The reversing plate 30 is attached to the second insertion hole 82 and is arranged so as to close the second insertion hole 82. In other words, the reversing plate 30 is arranged so as to cover the entire second insertion hole 82. The reversing plate 30 has a central portion 31 and an outer peripheral portion 32. The central portion 31 is convex downward when the internal pressure of the case 1 is lower than a predetermined value. The outer peripheral portion 32 is fixed to the lid portion 112 of the case 1. Therefore, the internal pressure of the case 1 acts on the lower surface of the reversing plate 30. As described above, the lid portion 112 is electrically connected to the second electrode terminal 7 and is insulated from the first electrode terminal 5. Therefore, the reversing plate 30 is electrically connected to the second electrode terminal 7 and is insulated from the first electrode terminal 5. The reversing plate 30 may be integrally molded with the lid portion 112 of the case 1, or may be molded separately from the lid portion 112 and then welded to the lid portion 112. When the reversing plate 30 and the lid portion 112 are integrally molded, the processing step at the time of manufacturing can be reduced, and the power storage device 100 can be manufactured more easily.

The energizing plate 20 is a metal member and has conductivity. The energizing plate 20 is formed in a substantially rectangular shape in a plan view. The energizing plate 20 is arranged outside the case 1 and is electrically connected to the first electrode terminal 5. The energizing plate 20 is arranged above the reversing plate 30 so as to cover the second insertion hole 82.

The insulating member 62 is arranged between the energizing plate 20 and the lid 112 of the case 1. The insulating member 62 is formed in a substantially rectangular shape in a plan view, and has a slightly larger area than the energizing plate 20. The lower surface of the insulating member 62 is in contact with the lid 112 of the case 1. The upper surface of the insulating member 62 is in contact with the energizing plate 20. The insulating member 62 supports the energizing plate 20 on the lid 112. The insulating member 62 insulates the energizing plate 20 and the lid portion 112, and also insulates the first electrode terminal 5 and the lid portion 112. Therefore, the energizing plate 20 is insulated from the lid portion 112. That is, the energizing plate 20 is insulated from the second electrode terminal 7. Further, in the insulating member 62, a portion where the second insertion hole 82 and the energizing plate 20 overlap is opened in a plan view. Specifically, the insulating member 62 has a through hole 62a having the same shape as the second insertion hole 82.

As shown in FIG. 3, the energizing plate 20 has a high-rigidity portion in a part of the portion overlapping the reversing plate 30 in a plan view. The high-rigidity portion has higher rigidity than the other portions of the energizing plate 20. In this embodiment, the high-rigidity portion is composed of a plurality of ribs 20a. The plurality of ribs 20a project from the upper surface of the energizing plate 20. When viewed in a plan view, the plurality of ribs 20a extend radially from the center of the reversing plate 30. In this embodiment, in a plan view, eight ribs 20a extend radially outward from the center of the reversing plate 30. A part of the plurality of ribs 20a (outer end portion in the radial direction) is formed so as to extend outward from the outer peripheral edge of the reversing plate 30 in a plan view. The number of ribs 20a is not limited to the above, and can be appropriately changed so that the energizing plate 20 has a desired strength. Further, the rib 20a may be integrally formed with the energizing plate 20, or may be formed separately from the energizing plate 20 and then joined to the energizing plate 20.

Here, a short-circuit operation between the first electrode terminal 5 and the second electrode terminal 7 by the short-circuit device 10 will be described with reference to FIGS. 2 and 4. In the power storage device 100 described above, the first electrode terminal 5 and the second electrode terminal 7 are used in a conductive state in which electricity can be supplied via an external device (for example, a generator, a motor, etc.). As shown in FIG. 2, when the pressure in the case 1 is equal to or less than a predetermined value, the reversing plate 30 is in a downwardly convex state. That is, the reversing plate 30 is electrically insulated from the energizing plate 20. As described above, the reversing plate 30 is electrically connected to the second electrode terminal 7 and is insulated from the first electrode terminal 5. Therefore, an energization path via the short-circuit device 10 is not formed between the first electrode terminal 5 and the second electrode terminal 7. That is, the first electrode terminal 5 and the second electrode terminal 7 are in an insulated state. On the other hand, when the internal pressure of the case 1 rises due to overcharging, the pressure acting on the lower surface of the reversing plate 30 rises. Therefore, when the pressure in the case 1 rises and reaches a predetermined value, as shown in FIG. 4, the reversing plate 30 reverses and changes to an upwardly convex state to come into contact with the energizing plate 20. That is, the reversing plate 30 comes into contact with the energizing plate 20 and is electrically connected. At this time, the reversing plate 30 is electrically connected to the second electrode terminal 7, and the energizing plate 20 is also electrically connected to the second electrode terminal 7. Therefore, when the energizing plate 20 and the reversing plate 30 come into contact with each other, an energizing path is formed between the first electrode terminal 5 and the second electrode terminal 7 via the energizing plate 20 and the reversing plate 30. That is, a short-circuited state is obtained in which the first electrode terminal 5 and the second electrode terminal 7 are short-circuited. This makes it possible to prevent current from flowing through the electrode assembly 3. Alternatively, the current flowing through the electrode assembly 3 becomes smaller.

In the power storage device 100 of the first embodiment, when the pressure in the case 1 reaches a predetermined value by the short-circuit device 10, the first electrode terminal 5 and the second electrode terminal 7 are short-circuited. In this short-circuited state, the high-rigidity portion (plurality of ribs 20a) can receive an impact force acting when the reversing plate 30 is connected to the energizing plate 20 (when colliding). Therefore, it is possible to prevent the energizing plate 20 from being deformed by the impact force acting on the energizing plate 20 from the reversing plate 30. Therefore, the contact between the reversing plate 30 and the energizing plate 20 in the short-circuited state can be preferably maintained.

Further, since the rib 20a also functions as a heat radiation fin, the heat exchange area of the energizing plate 20 becomes large. Therefore, the heat generated by the short-circuit current flowing through the reversing plate 30 and the energizing plate 20 in the short-circuited state can be efficiently dissipated to the atmosphere. Therefore, it is possible to prevent the reversing plate 30 from melting.

Next, the power storage device of the second embodiment will be described. In the following, only the differences from the first embodiment will be described, and the detailed description of the same configuration as the first embodiment will be omitted. The same applies to the other examples.

As shown in FIGS. 5 and 6, the energizing plate 24 has holes 26 formed in a range including the center of the reversing plate 30. The hole 26 penetrates from the upper surface to the lower surface of the energizing plate 24. The diameter of the hole 26 is smaller than the diameter of the second insertion hole 82. The outer peripheral edge of the hole 26 is located inside the outer peripheral edge of the second insertion hole 82 when viewed in a plan view. The high-rigidity portion of the energizing plate 24 is composed of a plurality of ribs 24a. The plurality of ribs 24a extend in the radial direction of the reversing plate 30 from the outer peripheral edge of the hole 26 of the energizing plate 24.

In the power storage device of the second embodiment, when the reversing plate 30 is inverted due to an increase in pressure in the case 1, the reversing plate 30 comes into contact with the outer peripheral edge of the hole 26 of the energizing plate 24, as shown in FIG. Therefore, the impact force acting on the energizing plate 20 can be reduced as compared with the case where the energizing plate 20 contacts only at the center of the reversing plate 30. Further, the contact area between the reversing plate 30 and the energizing plate 20 in the short-circuited state can be secured, and the contact resistance can be reduced. Therefore, Joule heat due to the short-circuit current can be reduced, and the inversion plate 30 can be prevented from melting.

Next, the power storage device of the third embodiment will be described. In the third embodiment, the configuration of the high-rigidity portion of the energizing plate 20 is different from that of the first embodiment. That is, as shown in FIG. 8, the high-rigidity portion of the energizing plate 20 is composed of the cured portion 20b whose dislocation density has increased due to work hardening. The cured portion 20b has a higher rigidity than the other portions 20d of the energizing plate 20. Various methods can be adopted for forming the cured portion 20b. For example, in the manufacturing process of the energizing plate 20, the portion to be the highly rigid portion (cured portion 20b) is made thicker than the other portions. It can be formed by plastic deformation by applying a high processing force to the portion. The cured portion 20b is formed at a position overlapping the reversing plate 30 in a plan view. The strength of the cured portion 20b can be adjusted by work hardening the current-carrying plate 20 to a dislocation density corresponding to a desired strength. The dislocation density as used herein is the total length of the dislocation lines in the crystal per unit volume, and the dislocation lines are linear crystal defects contained in the crystal. As the dislocation density increases, the interaction between the dislocation lines increases, and the dislocation lines become difficult to move (that is, the rigidity increases).

Also in the power storage device of the third embodiment, since the impact force acting on the energizing plate 20 from the reversing plate 30 can be received by the high rigidity portion, the same effect as that of the first embodiment can be obtained. The energizing plate 20 of this embodiment may have a hole penetrating from the upper surface to the lower surface thereof, like the energizing plate 24 used in the second embodiment.

Next, the power storage device of the fourth embodiment will be described. In the fourth embodiment, the configuration of the high-rigidity portion of the energizing plate 20 is different from that of the first embodiment. That is, as shown in FIG. 9, the high-rigidity portion of the energizing plate 20 is formed by joining the reinforcing plate 20c to the energizing plate 20. The reinforcing plate 20c is a metal member and has conductivity. The reinforcing plate 20c is formed in substantially the same shape as the reversing plate 30 in a plan view, and is arranged at a position overlapping the reversing plate 30. The thickness (vertical dimension) of the reinforcing plate 20c can be appropriately adjusted so that the energizing plate 20 has a desired strength.

Also in the power storage device of the fourth embodiment, since the impact force acting on the energizing plate 20 from the reversing plate 30 can be received by the high rigidity portion, the same effect as that of the first embodiment can be obtained. The energizing plate 20 of this embodiment may have a hole penetrating from the upper surface to the lower surface thereof, like the energizing plate 24 used in the second embodiment.

Although the examples of the techniques disclosed in the present specification have been described in detail above, these are merely examples and do not limit the scope of claims. The techniques described in the claims include various modifications and modifications of the specific examples illustrated above.

For example, in Examples 3 and 4, the high-rigidity portion was formed in a portion overlapping the reversing plate in a plan view, but was formed only in a portion where the reversing plate abuts on the current-carrying plate in a short-circuited state. You may. According to this configuration, space saving and material cost can be reduced.

Further, in the above-described embodiment, the short-circuit device 10 may be provided on the second electrode terminal 7 side. When the short-circuit device 10 is provided on the side of the second electrode terminal 7, an insulating member can be arranged between the second electrode terminal 7 and the lid portion 112 in the same manner as in the configuration of the above-described embodiment.

The technical elements described herein or in the drawings exhibit their technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the techniques illustrated in the present specification or drawings achieve a plurality of objectives at the same time, and achieving one of the objectives itself has technical usefulness.

1: Case 3: Electrode assembly 5: First electrode terminal 7: Second electrode terminal 10: Short circuit device 20, 24: Energizing plate 20a, 24a: Rib 20b: Hardened portion 20c: Reinforcing plate 26: Hole 30: Inverting plate 31: Central portion 32: Outer peripheral portion 51: Positive electrode current collecting tab 52: Negative electrode current collecting tab 53: Positive electrode lead 54: Negative electrode lead 61: Seal member 62: Insulating member 62a: Through hole 81: First insertion hole 82: Second Insertion hole 83: Third insertion hole 100: Power storage device 111: Main body 112: Lid

Claims (5)

With the case
The electrode assembly housed in the case and
A first electrode terminal and a second electrode terminal attached to the case and electrically connected to the electrode assembly,
An insulating state provided in the case in which the first electrode terminal and the second electrode terminal are insulated, and a short-circuited state in which the first electrode terminal and the second electrode terminal are short-circuited. It is equipped with a short-circuit device that switches to
The case has a first insertion hole and a second insertion hole that communicate the inside and the outside thereof.
The first electrode terminal is attached to the first insertion hole and is electrically insulated from the case.
The second electrode terminal is electrically connected to the case.
The short circuit device
An energizing plate arranged outside the case, electrically connected to the first electrode terminal, and covering at least a part of the second insertion hole.
An inversion plate that is electrically connected to the case, attached to the second insertion hole, and closes the second insertion hole.
In addition to insulating the case from the current-carrying plate and the first electrode terminal, an insulating member that opens at least a part of the portion where the second insertion hole and the current-carrying plate overlap in a plan view is provided. Ori,
The reversing plate is circular in a plan view, and is electrically insulated apart from the current-carrying plate in the insulated state, while is electrically in contact with the current-carrying plate in the short-circuited state. Being done
The current-carrying plate has a high-rigidity portion having a higher rigidity than the other portions in at least a part of the portion overlapping the reversing plate in a plan view.
The high-rigidity portion is one or more ribs.
The rib is a power storage device extending in the radial direction of the reversing plate. With the case
The electrode assembly housed in the case and
A first electrode terminal and a second electrode terminal attached to the case and electrically connected to the electrode assembly,
An insulating state provided in the case in which the first electrode terminal and the second electrode terminal are insulated, and a short-circuited state in which the first electrode terminal and the second electrode terminal are short-circuited. It is equipped with a short-circuit device that switches to
The case has a first insertion hole and a second insertion hole that communicate the inside and the outside thereof.
The first electrode terminal is attached to the first insertion hole and is electrically insulated from the case.
The second electrode terminal is electrically connected to the case.
The short circuit device
An energizing plate arranged outside the case, electrically connected to the first electrode terminal, and covering at least a part of the second insertion hole.
An inversion plate that is electrically connected to the case, attached to the second insertion hole, and closes the second insertion hole.
In addition to insulating the case from the current-carrying plate and the first electrode terminal, an insulating member that opens at least a part of the portion where the second insertion hole and the current-carrying plate overlap in a plan view is provided. Ori,
In the insulated state, the reversing plate is electrically insulated apart from the energizing plate, while in the short-circuited state, it abuts on the energizing plate and is electrically connected.
The current-carrying plate has a high-rigidity portion having a higher rigidity than the other portions in at least a part of the portion overlapping the reversing plate in a plan view.
The high-rigidity portion is one or more ribs.
A part of the rib is a power storage device located in a range including the outside of the outer peripheral edge of the reversing plate in a plan view. With the case
The electrode assembly housed in the case and
A first electrode terminal and a second electrode terminal attached to the case and electrically connected to the electrode assembly,
An insulating state provided in the case in which the first electrode terminal and the second electrode terminal are insulated, and a short-circuited state in which the first electrode terminal and the second electrode terminal are short-circuited. It is equipped with a short-circuit device that switches to
The case has a first insertion hole and a second insertion hole that communicate the inside and the outside thereof.
The first electrode terminal is attached to the first insertion hole and is electrically insulated from the case.
The second electrode terminal is electrically connected to the case.
The short circuit device
An energizing plate arranged outside the case, electrically connected to the first electrode terminal, and covering at least a part of the second insertion hole.
An inversion plate that is electrically connected to the case, attached to the second insertion hole, and closes the second insertion hole.
In addition to insulating the case from the current-carrying plate and the first electrode terminal, an insulating member that opens at least a part of the portion where the second insertion hole and the current-carrying plate overlap in a plan view is provided. Ori,
In the insulated state, the reversing plate is electrically insulated apart from the energizing plate, while in the short-circuited state, it abuts on the energizing plate and is electrically connected.
The current-carrying plate has a high-rigidity portion having a higher rigidity than the other portions in at least a part of the portion overlapping the reversing plate in a plan view.
The high-rigidity portion is a portion where the dislocation density has increased due to work hardening, which is a power storage device. With the case
The electrode assembly housed in the case and
A first electrode terminal and a second electrode terminal attached to the case and electrically connected to the electrode assembly,
An insulating state provided in the case in which the first electrode terminal and the second electrode terminal are insulated, and a short-circuited state in which the first electrode terminal and the second electrode terminal are short-circuited. It is equipped with a short-circuit device that switches to
The case has a first insertion hole and a second insertion hole that communicate the inside and the outside thereof.
The first electrode terminal is attached to the first insertion hole and is electrically insulated from the case.
The second electrode terminal is electrically connected to the case.
The short circuit device
An energizing plate arranged outside the case, electrically connected to the first electrode terminal, and covering at least a part of the second insertion hole.
An inversion plate that is electrically connected to the case, attached to the second insertion hole, and closes the second insertion hole.
In addition to insulating the case from the current-carrying plate and the first electrode terminal, an insulating member that opens at least a part of the portion where the second insertion hole and the current-carrying plate overlap in a plan view is provided. Ori,
In the insulated state, the reversing plate is electrically insulated apart from the energizing plate, while in the short-circuited state, it abuts on the energizing plate and is electrically connected.
The current-carrying plate has a high-rigidity portion having a higher rigidity than the other portions in at least a part of the portion overlapping the reversing plate in a plan view.
The high-rigidity portion is a portion where a reinforcing plate is joined to the current-carrying plate.
The high-rigidity portion is a power storage device formed only in a portion where the reversing plate comes into contact with the current-carrying plate in the short-circuited state. The energizing plate covers the entire second insertion hole in a plan view, and at least has a hole in a range including the center of the reversing plate.
The power storage device according to any one of claims 1 to 4, wherein the outer peripheral edge of the hole is located inside the outer peripheral edge of the second insertion hole.

Images