JP5509592B2 - Bipolar secondary battery - Google Patents

Description

  The present invention relates to a bipolar secondary battery, and an assembled battery and a vehicle including the same.

  In recent years, in order to cope with air pollution and global warming, reduction of the amount of carbon dioxide has been strongly desired. In the automobile industry, there is a great expectation for reducing carbon dioxide emissions by introducing electric vehicles (EV) and hybrid electric vehicles (HEV), and the development of secondary batteries for motor drive that holds the key to commercialization of these is thriving. Has been done.

  As a secondary battery for driving a motor, it is required to have extremely high output characteristics and high energy as compared with a consumer lithium ion secondary battery used for a mobile phone, a notebook personal computer or the like. Therefore, a hyperbolic secondary battery in which lithium ion secondary batteries having the highest theoretical energy among all the batteries (one secondary battery is called a single battery) are stacked in series is attracting attention. Development is progressing rapidly.

  Bipolar secondary batteries have variations in their internal resistance, capacity, etc. due to manufacturing variations, and therefore, when they are connected in series, there is variation in the voltage shared by each single cell. When a variation in the shared voltage of a single cell occurs, an excessive load is applied to the single cell with a large shared voltage, the deterioration proceeds from the single cell with the large shared voltage, and the life of the bipolar secondary battery as a whole is the shared voltage. May be limited by large single cells. For this reason, it is desirable to monitor the voltage of each unit cell and perform control to equalize the shared voltage.

Conventionally, in order to monitor the voltage of each unit cell, a tooth portion of a comb-shaped wiring board is inserted between each stacked current collector, and the tooth portion and each current collector are brought into contact with each other. The voltage of each current collector was taken out from the handle portion of the wiring board (Patent Document 1).
JP 2008-160060 A

  However, the tips of the wiring board teeth are exposed by removing the insulating material covering the conductive material in order to connect to the current collector. Therefore, a step is generated between the tip portion where the conductive material is exposed and a portion where the conductive material is not exposed, and the contact area between the tip portion of the tooth and the current collector is sufficient due to the step. There is a possibility of deteriorating the vibration durability of the adhesion between the two.

In order to solve the above problems, a bipolar secondary battery according to the present invention includes a current collector, a wiring board, and a conductive elastic body. The wiring board is inserted between the stacked current collectors, and has a plurality of teeth electrically connected to any one of the opposed current collectors, and supports the plurality of teeth, and the potentials of the plurality of teeth A handle having an output end for outputting. The teeth of the wiring board are composed of a base portion where the conductive material is coated with an insulating material and a tip portion where the conductive material is exposed, and the tip portion and the base portion are inserted between the current collectors. And electrically connected via a conductive elastic body provided between the tip of the tooth and the current collector. The conductive elastic body has a conductive adhesive layer on the surface, and the thickness of the insulating material covering the conductive material of the teeth is smaller than the thickness of the conductive elastic body, The current collector is electrically connected by being bonded to the conductive elastic body by the adhesive layer.

  According to the bipolar secondary battery of the present invention, the conductive elastic body is provided between the current collector and the tip of the tooth of the wiring board. Thereby, the influence of the step is reduced to ensure a sufficient contact area between the current collector and the wiring board, and vibration can be absorbed by the conductive elastic body, so that vibration durability can be improved. .

  Hereinafter, a bipolar secondary battery according to the present invention, an assembled battery in which a plurality of the secondary batteries are connected, and a vehicle equipped with these batteries will be described in detail by embodiments.

  First, a bipolar secondary battery will be briefly described by taking a bipolar lithium ion secondary battery (hereinafter referred to as a bipolar secondary battery) as an example. In the drawings to be referred to below, the shape, thickness and the like of the constituent elements of the bipolar secondary battery are exaggerated for the purpose of facilitating understanding of the invention.

  FIG. 1 is an external view of a bipolar secondary battery. FIG. 2 is a cross-sectional view of the bipolar secondary battery shown in FIG.

  As shown in FIG. 1, the bipolar secondary battery 100 has, for example, a rectangular flat shape, and a positive electrode tab 110 </ b> A and a negative electrode tab 110 </ b> B for taking out electric power from both sides thereof are drawn out. The power generation element 120 is wrapped with an exterior material (for example, a laminate film) 130 of the bipolar secondary battery 100, and the periphery thereof is heat-sealed, and is sealed with the positive electrode tab 110A and the negative electrode tab 110B pulled out. .

  As shown in FIG. 2, the power generation element 120 of the bipolar secondary battery 100 includes a bipolar secondary battery in which a positive electrode active material layer 210 and a negative electrode active material layer 220 are formed on each surface of a current collector 230. A plurality of electrodes 200 are provided. Each bipolar secondary battery electrode is stacked via the electrolyte layer 240 to form the power generation element 120. The adjacent positive electrode active material layer 210, electrolyte layer 240, and negative electrode active material layer 220 constitute one unit cell layer 100. Therefore, the bipolar secondary battery 100 has a configuration in which the single battery layers 200 are stacked. In addition, a seal member 250 for insulating between adjacent current collectors 230 is provided on the outer periphery of the opposing surface of each current collector 230.

  Hereinafter, each member of the bipolar secondary battery according to the embodiment of the present invention will be described.

[Electrode for bipolar secondary battery]
The electrode for a bipolar secondary battery has a current collector 230 and active material layers 210 and 220 provided on the surface thereof. More specifically, the positive electrode active material layer 210 is provided on one surface of one current collector, and the negative electrode active material layer 220 is provided on the other surface. Each active material layer contains an active material, and further contains other additives as necessary.

The positive electrode active material layer includes a positive electrode active material. Examples of the positive electrode active material include lithium-transition metal oxides such as LiMn ₂ O ₄ and LiNiO ₂ , lithium-transition metal phosphate compounds, and lithium-transition metal sulfate compounds. In some cases, two or more positive electrode active materials may be used in combination. A positive electrode active material other than the above may be used.

  The negative electrode active material layer includes a negative electrode active material. Examples of the negative electrode active material include carbon materials such as graphite, soft carbon, and hard carbon, lithium-transition metal compounds as described above, metal materials, and lithium-metal alloy materials. In some cases, two or more negative electrode active materials may be used in combination. Negative electrode active materials other than those described above may be used.

  The average particle diameter of each active material contained in the active material layers of the positive electrode and the negative electrode is not particularly limited, but is preferably 0.01 to 100 μm, more preferably 1 to 50 μm. However, a form outside this range may be adopted.

[Electrolyte layer]
There is no restriction | limiting in particular in the electrolyte which comprises an electrolyte layer, Polymer electrolytes, such as a liquid electrolyte, a polymer gel electrolyte, and a polymer solid electrolyte, can be used.

The liquid electrolyte has a form in which a lithium salt as a supporting salt is dissolved in an organic solvent as a plasticizer. Examples of the organic solvent used as the plasticizer include carbonates such as ethylene carbonate (EC) and propylene carbonate (PC). As the supporting salt (lithium _{salt), LiN (SO 2 C 2} F 5) 2, LiN (SO 2 CF 3) 2, LiPF 6, LiBF 4, LiClO 4, LiAsF 6, LiSO 3 CF 3 and the like of the electrode A compound that can be added to the active material layer can be similarly used.

  On the other hand, the polymer electrolyte is classified into a gel electrolyte containing an electrolytic solution and a polymer solid electrolyte containing no electrolytic solution. The gel electrolyte has a configuration in which the above liquid electrolyte is injected into a matrix polymer having lithium ion conductivity. Examples of the matrix polymer having lithium ion conductivity include polyethylene oxide (PEO), polypropylene oxide (PPO), and copolymers thereof. In such a matrix polymer, an electrolyte salt such as a lithium salt can be well dissolved. The polymer solid electrolyte has a structure in which a supporting salt (lithium salt) is dissolved in the matrix polymer, and does not include an organic solvent that is a plasticizer. Therefore, when the electrolyte layer is composed of a polymer solid electrolyte, there is no fear of liquid leakage from the battery, and the battery reliability can be improved.

  A matrix polymer of a polymer gel electrolyte or a polymer solid electrolyte can exhibit excellent mechanical strength by forming a crosslinked structure. In order to form a crosslinked structure, thermal polymerization, ultraviolet polymerization, radiation polymerization, electron beam polymerization, etc. are performed on a polymerizable polymer (for example, PEO or PPO) for forming a polymer electrolyte using an appropriate polymerization initiator. A polymerization treatment may be performed.

  In addition, when an electrolyte layer is comprised from a liquid electrolyte or a gel electrolyte, you may use a separator for an electrolyte layer. Specific examples of the separator include a microporous film made of polyolefin such as polyethylene or polypropylene.

[Seal member]
In the bipolar secondary battery 100, the seal member 250 is usually provided on the outer periphery of the opposing surface of each current collector 230, that is, around each single cell layer 200. The sealing member 250 is used for the purpose of preventing short circuit caused by contact between adjacent current collectors 230 in the battery or slight unevenness of the end of the single cell layer 200 in the power generation element 120. Provide. By providing the seal member 250, long-term reliability and safety are ensured, and a high-quality bipolar secondary battery 100 can be provided.

  As the material of the seal member 250, a material having insulating properties, a seal property against dropping of the solid electrolyte, a seal property (sealing property) against moisture permeation from the outside, and a heat resistance at a battery operating temperature is used. For example, urethane resin, epoxy resin, polyethylene resin, polypropylene resin, polyimide resin, and rubber can be used. Among these, polyethylene resins and polypropylene resins can be suitably used from the viewpoints of corrosion resistance, chemical resistance, ease of production (film forming properties), economy, and the like.

[Positive electrode tab and negative electrode tab]
For the purpose of extracting power to the outside of the battery, tabs (positive electrode tab 110A and negative electrode tab 110B) that are electrically connected to the current collector 230 having the maximum potential and the minimum potential in the battery element 120 are provided outside the battery exterior member 130. Provide to pull out.

  A highly conductive material is used as the material constituting the tab. As the highly conductive material, it is desirable to use metal materials such as aluminum, copper, titanium, nickel, stainless steel (SUS), and alloys thereof. Further, it is more desirable to use aluminum and copper from the viewpoint of light weight, corrosion resistance, and high conductivity.

[Battery exterior materials]
As the battery exterior member 130, a bag-like case using a laminate film containing aluminum that can cover the power generation element can be used in addition to a metal can case. As the laminate film, for example, a laminate film having a three-layer structure in which polypropylene, aluminum, and nylon are laminated in this order can be used, but is not limited thereto.

  Next, the bipolar secondary battery according to the present invention will be described in detail.

  FIG. 3 is a view showing a part (a power generation element and a wiring board) of a sectional view of the bipolar secondary battery according to the embodiment of the present invention.

  As shown in FIG. 3, the power generation element 120 is configured by stacking a plurality of unit cell layers 200, which are minimum units constituting a battery, via a current collector 230. Therefore, the current collector 230 is stacked via the single battery layer 200. The wiring substrate 300 having a comb shape is inserted between the current collectors in which the portions of the teeth 301 are stacked, and electrically connected to any one of the opposing current collectors 230. The output end 302a of the wiring board 300 has a number of output terminals 302b corresponding to the plurality of teeth 301, and is individually connected to each of the plurality of teeth 301 by wiring.

  As described above, the wiring board 300 has a comb-like shape including a plurality of teeth 301 and a handle 302 that supports the teeth 301, and is electrically connected to each current collector 230. The voltages applied from the body 230 to the teeth 301 of the wiring board 300 can be separately output from the output end 302a. Thereby, the voltage of each laminated | stacked collector can be taken out from the exterior material of a bipolar secondary battery from the output end 302a of a wiring board. That is, the voltage of each unit cell 200 can be monitored from outside the exterior material.

  FIG. 4 is a diagram showing a part of a cross-sectional view of the bipolar secondary battery according to the present embodiment, and is an enlarged view of a portion within a thick line A in FIG. 3.

  As shown in FIG. 4, the tooth 301 of the wiring board 300 includes a tip portion 301a and a base portion 301b. The base 301b has a structure in which a conductive material 303 is covered with insulating materials 304a and 304b. The tip portion 301a has a structure in which a part (304b) of the insulating material 304a, 304b is removed. Then, the portion of the tip 301 a of the tooth 301 where the conductive material 303 is exposed and the current collector 230 are electrically connected via the conductive elastic body 400. As a result, the teeth 301 and the current collector 230 are electrically connected.

  FIG. 9 is a reference diagram showing a case where the tip portion 301a of the tooth 301 of the wiring board 300 and the current collector 230 are electrically connected without using the conductive elastic body 400, unlike the present embodiment. As described above, in order to configure the tip portion 301, a part (304b) of the insulating material 304a, 304b is removed from a part of the tooth 301 of the wiring board 300. For this reason, a level difference corresponding to the thickness of the removed insulating material 304 b is generated between the tip portion 301 and the base portion 302. When a conductive elastic body is not provided between the tip 301a of the tooth 301 of the wiring board 300 and the current collector 230, the tip of the tooth and the current collector are affected by the step as shown in FIG. A sufficient contact area cannot be secured. Further, since a space is generated between the current collector 230 and the wiring board, a seal member described later may enter the electrical contact portion. Then, it may be difficult to make the electrical connection between the wiring board 300 and the current collector 230 low resistance and high reliability.

  In the bipolar secondary battery according to the present embodiment, as shown in FIG. 4, a conductive elastic body 400 is provided between the tip 301 a of the tooth 301 and the current collector 230, and the conductive material 303 of the tooth 301 and The current collector 230 is brought into contact (that is, electrically connected) with the conductive elastic body 400. Thereby, the teeth 301 of the wiring board 300 and the current collector 230 are electrically connected. By adopting such a structure, the bipolar secondary battery according to this embodiment can reduce the influence of the step and ensure a sufficient contact area between the current collector and the wiring board. Further, the vibration durability of the bipolar secondary battery can be improved by causing the conductive elastic body to absorb the vibration.

  For example, copper can be used as the conductive material 303, and polyimide can be used as the insulating materials 304a and 304b, for example. By using polyimide, the temperature resistance performance and vibration resistance strength of the bipolar secondary battery can be increased, and the reliability can be improved.

  Here, the thickness of the insulating material 304 b that covers the conductive material 303 of the teeth 301 of the wiring board 300 is desirably smaller than the thickness of the conductive elastic body 400. As a result, a sufficient contact area between the current collector and the wiring board can be ensured, and electrical connection with low resistance and high reliability can be realized.

  In order to bring the conductive material 303 and the current collector 230 of the tooth 301 into contact with the conductive elastic body 400, the seal member 250 can be used. That is, in general, in the bipolar secondary battery, in order to prevent the adjacent current collectors 230 in the battery from coming into contact with each other, a seal member ( Adhesive) 250 is provided. Therefore, the seal member 250 is used to make the seal member 250 cover the tip portion 301 of the tooth 301, thereby maintaining the contact between the conductive material of the tooth 301 and the current collector 230 and the conductive elastic body 400. can do. Such a structure is obtained by molding the seal member 250 in a state where the conductive material 303 of the teeth 301 and the current collector 230 are in contact with the conductive elastic body 400 in the process of molding the wiring board with the seal member 250. realizable. Specifically, the conductive elastic body 400 and the current collector 230 provided at the tip 301 of the tooth 301 are attached with a conductive double-sided tape, and the periphery of the tooth 301 is molded and fixed with a seal member. Thereby, simple, inexpensive and strong electrical connection can be realized between the wiring board 300 for voltage monitoring and each unit cell 200 of the bipolar secondary battery.

  The conductive elastic body 400 is bonded to the wiring board 300 and the current collector 230 by a method such as heat fusion or thermosetting. The seal member 250 is disposed between the current collector 230 and the electrolyte layer (separator) 240, covers the wiring substrate 300, and adheres the electrolyte layer 240 and the current collector 230. As a result, a structure in which a sealing member or gas as an insulator does not enter the bonding portion between the current collector 230 and the wiring substrate 300 (that is, the tip portion 301a of the tooth 301 of the wiring substrate 300) is realized. And the contact with the wiring board 300 can be maintained. Further, since there is an adhesive force between the conductive material 303 and the conductive elastic body 400 of the wiring board 300 and between the conductive elastic body 400 and the current collector 230, peeling due to stress concentration during vibration is caused. Generation | occurrence | production can be prevented and a reliable electrical connection can be maintained.

  Further, as described above, a step is formed at the boundary between the tip portion 301a and the base portion 301b of the tooth 301 of the wiring board 300, but when the vibration is introduced, bending is concentrated on such a step and breakage is likely to occur. However, in the molding process of the seal member 250, the stepped portion is molded and reinforced by the seal member, so that concentration of bending and eventually disconnection can be prevented, and highly reliable electrical connection can be realized.

  It is desirable to use a conductive elastic body 400 whose melting point is higher than the melting point or thermosetting temperature of the sealing member 250. Accordingly, the thermoplastic conductive elastic body 400 is not dissolved in the process of molding the wiring board 300 with the sealing member 250, and the conductive elastic body 400 and the wiring board are connected between the conductive elastic body 400 and the current collector 230. Since there is no space between 300, the seal member 250 can be prevented from entering the electrical contact portion, and a low-resistance and highly reliable electrical connection can be realized. Further, since the conductive elastic body 400 has elasticity, it absorbs vibration. Therefore, by using the conductive elastic body 400, the vibration durability of the bipolar secondary battery can be improved. As the conductive elastic body 400, for example, a conductive rubber sheet in which carbon is dispersed in rubber can be used.

  FIG. 5 is a diagram showing another example of the bipolar secondary battery according to the present embodiment.

  As shown in FIG. 5, the teeth 301 of the wiring board 300 are inserted between the opposing current collectors 230, and one of the current collectors 230 and the conductive material 303 exposed at the tip 301 a of the teeth 301 are electrically conductive. Electrical connection is made via the elastic body 400. At this time, a conductive and adhesive adhesive layer 500 is provided on the surface of the conductive elastic body 400, and the tips 301 a of the teeth 301 of the wiring substrate 300 and the conductive elastic body 400 are electrically connected via the adhesive layer 500. Connect. In addition, the current collector 230 and the conductive elastic body 400 are electrically connected through the adhesive layer 500. Thereby, the teeth 301 of the wiring board 300 and the current collector 230 are electrically connected.

  As described above, the use of the conductive elastic body 400 having the adhesive layer 500 eliminates the need for a heat treatment step for connection, which is necessary when a thermoplastic resin or a thermosetting resin is used. Cost reduction. In addition, since the periphery of the teeth 301 of the wiring board 300 is molded with a sealant, gas enters between the conductive elastic body 400, the teeth 301 of the wiring board 300, and the current collector 230, resulting in poor contact. You can prevent it from happening.

  Here, it is desirable that the adhesive layer 500 provided on the surface of the conductive elastic body 400 has a glass transition temperature lower than the thermosetting temperature or melting point of the seal member 250. In the molding process of the seal member 250, the seal member 250 can be molded at a temperature equal to or higher than the glass transition temperature of the adhesive layer 500. Therefore, when the seal member 250 is applied, the adhesive layer 500, the wiring board 300, and the current collector 230 are separated. Adhesion can be maintained between them, and the sealing member 250 can be prevented from entering the electrical contact portion. Therefore, by preventing the seal member 250 from entering the electrical contact portion, it is possible to realize a reliable electrical connection with low resistance. As the adhesive layer 500, for example, a conductive double-sided tape in which carbon fibers are dispersed in an acrylic pressure-sensitive adhesive can be used.

  FIG. 6 is a surface view showing a wiring board of a bipolar secondary battery according to the present invention.

  As shown in FIG. 6, the wiring board 300 has a comb shape composed of teeth 301 and a handle 302. The tooth 301 includes a base 301b having a structure in which a conductive material is covered with an insulating material, and a tip 301a having a structure in which the conductive material is exposed on the insulating material. The portion of the handle 302 of the wiring board 300 supports the portion of the teeth 301 and has an output end 302 a for outputting the voltages of the plurality of teeth 301. The output end 302a has a plurality of terminals 302b that output the voltages of the plurality of teeth 301, respectively.

  In order to output the voltage of the tooth 301 from the output end 302a, the wiring board 300 has a plurality of wires (not shown) individually extended from the tip 301a of the tooth 301 to the output terminal 302b of the output end 302a of the handle 302. Can have. The wiring substrate 300 can be manufactured by bonding a copper foil to a polyimide film and shaping the pattern, and covering the copper with the patterned polyimide film.

  FIG. 7 is an external view of an embodiment of an assembled battery in which a plurality of bipolar secondary batteries according to this embodiment are connected. FIG. 7A is a plan view of the assembled battery, and FIG. 7B is an assembled battery. FIG. 7C is a side view of the assembled battery.

  As shown in FIG. 7, the assembled battery 700 according to the embodiment of the present invention includes a small assembled battery 750 that can be attached and detached by connecting a plurality of bipolar secondary batteries according to the embodiment of the present invention in series or in parallel. It is also possible to form a plurality of small assembled batteries 750 that are detachable and connected in series or in parallel.

  As a result, it is possible to form the assembled battery 700 having a large capacity and a large output suitable for a vehicle driving power source and an auxiliary power source that require high volume energy density and high volume power density. In the assembled battery shown in FIG. 7, the prepared small detachable assembled battery 750 is connected to each other using an electrical connection means such as a bus bar. The assembled battery 750 is connected using a connection jig 710. Multiple layers are stacked. How many non-bipolar or bipolar secondary batteries are connected to create the assembled battery 750, and how many assembled batteries 750 are stacked to produce the assembled battery 700 depends on the vehicle ( It can be determined according to the battery capacity and output of the electric vehicle. That is, the capacity and voltage of the battery can be freely adjusted by serializing and paralleling the secondary batteries. Moreover, cost reduction can be realized.

  FIG. 8 is a diagram showing an electric vehicle 800 equipped with a bipolar secondary battery or an assembled battery according to an embodiment of the present invention. As shown in FIG. 8, the bipolar secondary battery 810 according to the present invention can be mounted under the seat 820 in the center of the vehicle body of the electric vehicle 800. When mounted under the seat 820, there is an advantage that the interior space and the trunk room can be widened. Note that the place where the secondary battery 810 according to the present invention is mounted is not limited to the under-seat 820. That is, the secondary battery according to the present invention can be mounted in a lower part of the rear trunk room or an engine room in front of the vehicle. By using the lithium ion battery according to the present embodiment for a vehicle such as a hybrid vehicle or an electric vehicle, the vehicle can have a long life and high reliability. In addition, the cost of the vehicle can be reduced.

  Although the present embodiment relates to a bipolar secondary battery, the present embodiment can also be applied to a stacked secondary battery in which single cells are connected in parallel instead of the bipolar secondary battery.

Hereinafter, effects of the bipolar secondary battery according to the embodiment of the present invention, a battery pack in which a plurality of the batteries are connected, and a vehicle equipped with these batteries are shown.
-By providing a conductive elastic body between the current collector and the tip of the wiring board teeth, the influence of the level difference of the wiring board is reduced, and a sufficient contact area between the current collector and the wiring board is secured. Therefore, it is possible to improve reliability by improving vibration durability.
-By providing a conductive elastic body between the current collector and the tip of the wiring board tooth, vibration can be absorbed by the conductive elastic body, and reliability can be improved by improving vibration durability.

It is an external view of a bipolar secondary battery. It is sectional drawing of a bipolar secondary battery. It is the figure which showed a part of sectional drawing of the bipolar secondary battery which concerns on embodiment of this invention. It is an enlarged view which shows a part of sectional drawing of the bipolar secondary battery which concerns on this embodiment. It is an enlarged view which shows a part of sectional drawing of the other example of the bipolar secondary battery which concerns on this embodiment. It is a surface view which shows the wiring board of the bipolar secondary battery which concerns on this embodiment. It is an external view of an embodiment of an assembled battery in which a plurality of bipolar secondary batteries according to this embodiment are connected. It is a figure which shows the electric vehicle 700 carrying the bipolar secondary battery or assembled battery which concerns on embodiment of this invention. FIG. 5 is a reference diagram showing a bipolar secondary battery in which a tip of a wiring board tooth and a current collector are electrically connected without using a conductive elastic body.

Explanation of symbols

100 Bipolar lithium ion secondary battery (bipolar secondary battery),
120 power generation elements,
130 exterior material,
200 cell layer,
210 positive electrode active material layer,
220 negative electrode active material layer,
230 current collector,
240 electrolyte layer,
250 seal member,
300 wiring board,
301 teeth,
301a tip,
301b base,
302 handle,
302a output end,
302b output terminal,
303 conductive material,
304a insulating material,
304b insulating material,
400 conductive elastic body,
500 adhesive layer,
700 battery packs,
800 Electric car (vehicle).

Claims (5)

A plurality of teeth inserted between the stacked current collectors and electrically connected to any one of the opposed current collectors, and supporting the plurality of teeth and outputting potentials of the plurality of teeth And a comb-shaped wiring board having a handle having an output end,
The tooth includes a base part in which a conductive material is coated with an insulating material and a tip part from which the conductive material is exposed. The tip part and the base part are inserted between the current collectors, and the tooth and the current collector Is electrically connected via a conductive elastic body provided between the tip of the tooth and the current collector,
The conductive elastic body has a conductive adhesive layer on a surface thereof, and the thickness of the insulating material covering the conductive material of the teeth is smaller than the thickness of the conductive elastic body, and the tip and The bipolar secondary battery, wherein the current collector is bonded to the conductive elastic body by the adhesive layer. A plurality of teeth inserted between the stacked current collectors and electrically connected to any one of the opposed current collectors, and supporting the plurality of teeth and outputting potentials of the plurality of teeth And a comb-shaped wiring board having a handle having an output end,
The teeth conductive material consists of a tip where the conductive material and coated base with an insulating material is exposed, before and SL tip and the base is inserted between the current collector, the current collector and the teeth The body is electrically connected via a conductive elastic body provided between the tip of the tooth and the current collector, and the thickness of the insulating material covering the conductive material of the tooth is A hyperbolic secondary battery characterized by being thinner than the thickness of the conductive elastic body . A seal member provided between the outer peripheral portions of the current collectors facing each other;
Bipolar secondary battery according to claim 1 or 2, wherein the sealing member is characterized in that covers the tip. The bipolar secondary battery according to claim 3 , wherein a melting point of the conductive elastic body is higher than a melting point or a thermosetting temperature of the seal member. The glass transition temperature of the adhesive layer, bipolar secondary battery according to claim 3 or 4, wherein the lower melting point or thermal curing temperature of the sealing member.

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