JP6326272B2 - Battery case and metal-air battery - Google Patents

Description

  The present invention relates to a battery case and a metal-air battery.

Since metal-air batteries have high energy density, they are attracting attention as next-generation batteries. The metal-air battery is discharged by using a metal electrode containing an electrode active material and disposed in an electrolyte as an anode and an air electrode as a cathode.
As a typical metal-air battery, a zinc-air battery using metal zinc as an electrode active material can be mentioned. In a zinc-air battery, it is considered that an electrode reaction of the following chemical formula 1 proceeds at the cathode.
(Chemical formula 1): O ₂ + 2H ₂ O + 4e ⁻ → 4OH ⁻
Further, it is considered that an electrode reaction (zinc dissolution reaction) as shown in the following chemical formula 2 proceeds at the anode.
(Chemical formula 2): Zn + 4OH ⁻ → Zn (OH) ₄ ²⁻ + 2e ⁻
The OH ^- ions consumed in Chemical Formula 2 are supplied by the electrode reaction of Chemical Formula 1. Therefore, as the anode-cathode distance decreases, OH ^- ions are more easily supplied to the anode, and the output characteristics of the metal-air battery are improved.
In addition, Zn (OH) ₄ ²⁻ generated in Chemical Formula 2 precipitates in the electrolyte as zinc oxide or zinc hydroxide as its concentration increases.

When such an electrode reaction proceeds, the electrode active material of the metal electrode is consumed and gradually decreases, and when the electrode active material runs out, the discharge stops. Therefore, mechanical charging is known in which the metal-air battery can be re-discharged by replacing the metal electrode and supplying the electrode active material to the zinc-air battery (see, for example, Patent Document 1).
Further, a metal-air battery having a mechanism for moving a separator disposed between an anode and a cathode is known (for example, see Patent Document 2).

JP 7-45270 A JP 2012-89328 A

However, in the conventional metal-air battery of mechanical charging, there is a risk that the metal electrode may come into contact with the battery case and damage the metal-air battery as the metal electrode is taken out or inserted, or the metal electrode insertion place may be worn. is there.
This invention is made | formed in view of such a situation, and provides the battery case which can suppress the damage and abrasion accompanying taking out and insertion of a metal electrode.

  The present invention provides a battery case comprising an air electrode and a deformation mechanism that changes a distance between opposing side walls, wherein the air electrode is provided on at least one of the opposing side walls.

According to the present invention, since the air electrode is provided on at least one of the opposing side walls of the battery case, the metal-air battery can be formed by inserting the metal electrode into the battery case between the opposing side walls. .
According to the present invention, since the deformation mechanism for changing the distance between the opposing side walls is provided, the metal electrode can be inserted into the battery case after the battery case is deformed so that the distance between the opposing side walls is widened. Further, the metal electrode can be taken out from the battery case. Thereby, it can suppress that a metal electrode and a battery case contact in the case of insertion and extraction of a metal electrode, and can suppress damage and abrasion of a metal electrode or a battery case. Further, after the metal electrode is inserted, the battery case can be deformed so that the interval between the opposing side walls becomes narrow, and the metal-air battery can be discharged. As a result, the distance between the anode and the cathode can be reduced, and the ion conduction resistance can be reduced. As a result, the output characteristics of the metal-air battery can be improved.

It is a schematic sectional drawing of the metal air battery of one Embodiment of this invention. It is a schematic sectional drawing of the metal air battery of one Embodiment of this invention. It is a schematic sectional drawing of the battery case and metal electrode cartridge of one Embodiment of this invention. (A) (b) is a schematic sectional drawing of the metal air battery of one Embodiment of this invention. (A) (b) is a schematic sectional drawing of the metal air battery of one Embodiment of this invention. (A) (b) is a schematic sectional drawing of the metal air battery of one Embodiment of this invention. (A) is a schematic sectional drawing of the metal air battery of one Embodiment of this invention, (b) is a schematic side view of the said metal air battery. (A) is a schematic sectional drawing of the metal air battery of one Embodiment of this invention, (b) is a schematic side view of the said metal air battery. It is a schematic sectional drawing of the battery case and metal electrode cartridge of one Embodiment of this invention. (A) is a schematic sectional drawing of the metal air battery of one Embodiment of this invention, (b) is a schematic side view of the said metal air battery. (A) (b) is a schematic top view of the metal air battery of one Embodiment of this invention.

The battery case of the present invention includes an air electrode and a deformation mechanism that changes an interval between opposing side walls, and the air electrode is provided on at least one of the opposing side walls.
In the present invention, the battery case is a component of a metal-air battery and is a battery case that can accommodate an electrolyte and a metal electrode.

In the battery case of the present invention, the deformation mechanism preferably includes a telescopic structure.
According to such a structure, the space | interval of the opposing side wall can be changed by expanding / contracting an expansion-contraction structure.
In the battery case of the present invention, it is preferable that at least one of the opposing side walls is provided with a pressing part, and the pressing part is provided so as to press the electrolyte in the battery case by narrowing the interval between the opposing side walls. .
According to such a structure, the electrolyte in a battery case can be supplied between an air electrode and a metal electrode by narrowing the space | interval of the opposing side wall by a deformation | transformation mechanism. Moreover, it can suppress that a metal electrode corrodes by widening the space | interval of the opposing side wall by a deformation | transformation mechanism.

In the battery case of the present invention, the deformation mechanism preferably has a rotation axis and is a mechanism that deforms with rotation about the rotation axis.
According to such a structure, the space | interval of the opposing side wall can be changed by changing a battery case by rotation centering on a rotating shaft. Further, it is possible to reduce the frictional force applied in the in-plane direction when the metal electrode or the metal electrode cartridge contacts the battery case.
The battery case of the present invention preferably further comprises a first separator that covers the inner surface of the air electrode.
According to such a structure, it can suppress that the very fine particle | grains of the negative electrode active material and negative electrode reaction product which are contained in electrolyte adhere to an air electrode. Moreover, when inserting a metal electrode in a battery case, or taking out a metal electrode from the inside of a battery case, it can suppress that a battery case is worn out or damaged.

The present invention also provides a metal-air battery including the battery case of the present invention, an electrolyte accommodated in the battery case, and a metal electrode accommodated in the battery case.
Moreover, this invention is equipped with the battery case of this invention, and the metal electrode cartridge in which at least one part was accommodated in the battery case, and a metal electrode cartridge is a metal provided with the 2nd separator which accommodated the metal electrode and electrolyte. An air battery is also provided.
According to the metal-air battery of the present invention, since the battery case includes an air electrode, the electrolyte accommodated in the battery case, and the metal electrode accommodated in the battery case, the anode reaction can proceed in the metal electrode. The cathode reaction can proceed at the air electrode. Thereby, an electromotive force can be generated between the metal electrode and the air electrode, and a discharge current can flow.
Moreover, by providing a metal electrode cartridge, a used metal electrode can be taken out from a battery case, a new metal electrode can be inserted in a battery case, and a metal electrode can be replaced | exchanged. By this exchange, an electrode active material can be supplied to the metal-air battery, and repeated discharge can be performed by the metal-air battery. Moreover, it is possible to prevent the electrode active material from self-corrosion by taking out the metal electrode from the battery case when the discharge is stopped, and the electrode active material can be used efficiently. Furthermore, by keeping the metal oxide deposited during the discharge in the second separator, the metal oxide can be removed from the battery case simultaneously with the metal electrode after the discharge.
Furthermore, this invention provides the metal air battery which made the 2nd separator into the bag shape. By making the second separator into a bag shape, the deformation mechanism can easily change the shape without repelling the pressure received from the opposite side wall or pressing portion of the battery case. It can be adhered.

The metal-air battery of the present invention further includes an external connection terminal, and the external connection terminal is provided so as to be electrically connected to at least one of the metal electrode and the air electrode by narrowing the interval between the opposing side walls. It is preferable.
According to such a configuration, the discharge of the metal-air battery can be started by deforming the battery case so that the distance between the opposing side walls becomes narrow, and the battery case is set so that the distance between the opposite side walls becomes wide. By deforming, the discharge of the metal-air battery can be stopped. This simplifies the operations associated with the start and stop of discharge. In addition, malfunction of the metal-air battery can be suppressed. Moreover, the safety of the metal-air battery can be improved.
In the metal-air battery of the present invention, it is preferable that the first and second separators are in contact with each other in a state where the battery case is deformed so as to narrow the interval between the opposing side walls.
According to such a configuration, the anode-cathode distance can be stabilized, and the output characteristics of the metal-air battery can be improved.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The configurations shown in the drawings and the following description are examples, and the scope of the present invention is not limited to those shown in the drawings and the following description.

Structure of battery case and structure of metal-air battery FIG. 1, FIG. 2, FIG. 4 (a) (b), FIG. 5 (a) (b), FIG. 6 (a) (b), FIG. 8 (a) and 10 (a) are schematic cross-sectional views of the metal-air battery of this embodiment, respectively. 3 and 9 are schematic cross-sectional views of the battery case and the metal electrode cartridge of this embodiment, respectively. FIGS. 7B, 8B, and 10B are schematic side views of the metal-air battery of this embodiment, respectively. 11 (a) and 11 (b) are schematic top views of the metal-air battery of this embodiment, respectively.
The battery case 32 of the present embodiment includes the air electrode 9 and the deformation mechanism 12 that changes the interval between the opposing side walls, and the air electrode 9 is provided on at least one of the opposing side walls.
The metal-air battery 30 of this embodiment includes a battery case 32, an electrolyte 3 accommodated in the battery case 32, and a metal electrode 5 accommodated in the battery case 32.
Hereinafter, the battery case 32 and the metal-air battery 30 of this embodiment are demonstrated.

1. Metal-air battery The metal-air battery 30 of the present embodiment is a battery in which the metal electrode 5 containing a metal serving as an electrode active material is a negative electrode (anode) and the air electrode 9 is a positive electrode (cathode). For example, a zinc air battery, a lithium air battery, a sodium air battery, a calcium air battery, a magnesium air battery, an aluminum air battery, and an iron air battery. Further, the metal-air battery 30 of the present embodiment may be a primary battery or a secondary battery. Further, the metal-air battery 30 of the present embodiment may be a mechanical rechargeable metal-air battery that supplies the electrode active material to the metal-air battery by replacing the metal electrode 5.
The metal-air battery 30 has a battery case 32 composed of the casing 1, the air electrode 9 and the like, and a structure that can be attached to and detached from the battery case 32, and a metal electrode cartridge 20 composed of the metal electrode 5, the second separator 14, and the like. May be configured.

2. Cell The cell 31 is a structural unit of the metal-air battery 30 and includes an electrode pair provided in the battery case 32 and including a metal electrode 5 serving as an anode and an air electrode 9 serving as a cathode. The cell 31 includes a battery case 32 including an air electrode and a metal electrode 5. The cell 31 may have, for example, an electrode pair in which one air electrode 9 and one metal electrode 5 are provided so as to sandwich the electrolyte 3, and 2 cells like the metal-air battery 30 shown in FIG. One air electrode 9 may have an electrode pair provided so as to sandwich one metal electrode 5. The electrolyte 3 sandwiched between the air electrode 9 and the metal electrode 5 may be an electrolytic solution or a solid electrolyte, or an electrolytic solution immersed in the separator or an electrolytic solution in the separator.

3. Cell aggregate The cell aggregate is composed of a plurality of cells 31. The cell aggregate may have a stack structure in which the cells 31 are stacked. The cell assembly may have a structure in which a plurality of cells 31 are arranged so that the plate-like metal electrode 5 or the air electrode 9 included in the cell 31 is located on the same plane. In the cell aggregate, a plurality of cells 31 may be provided in one housing 1, and each cell 31 may have the housing 1. The number of cells constituting the cell assembly is not particularly limited, and the number of cells may be determined according to the required power generation capacity.

4). Electrolyte, Battery Case, Deformation Mechanism The electrolyte 3 is an electrolyte responsible for ion conduction between the metal electrode 5 and the air electrode 9. The electrolyte 3 may be an electrolytic solution, a gelled electrolytic solution, a solid electrolyte or an electrolyte membrane (ion exchange membrane), an electrolytic solution soaked in the separator, or an electrolytic solution in the separator.
By using the electrolyte 3 as a gelled electrolyte, it is possible to suppress leakage of the electrolyte 3 when the metal electrode 5 is replaced as compared with the electrolyte. Further, the electrolyte 3 may be changed from a liquid to a gel at an arbitrary timing. Moreover, the gelled electrolyte may have fluidity or may not have fluidity.
The electrolyte 3 according to the embodiment shown in FIG. 1 is an electrolytic solution 3 accommodated in a battery case 32. The electrolytic solution 3 is an electrolytic solution in which an electrolyte is dissolved in a solvent and has ionic conductivity.
Moreover, the electrolyte solution 3 may be prepared by dissolving electrolyte particles in water or an organic solvent in the battery case 32, or the electrolyte solution 3 prepared outside may be put in the battery case 32. Further, the electrolytic solution 3 may be gelled in the battery case 32, or the electrolytic solution 3 that is gelled outside may be put in the battery case 32. Moreover, you may put the gelatinized electrolyte solution 3 in the battery case 32, after shape | molding.
The electrolyte 3 according to the embodiment shown in FIG. 10 is an ion exchange membrane such as an anion exchange membrane constituting the first separator 15 and the second separator 14 or a solid, gel, or polymer molecular sieve impregnated with an electrolyte. When the electrolyte 3 is the first separator 15 or the second separator 14, the first separator 15 or the second separator 14 is provided in contact with the electrode active material layer 6. As a result, the anode reaction can proceed at the interface between the electrode active material layer 6 and the first or second separator 15, 14. Further, when the first separator 15 and the second separator 14 are made to function as the electrolyte 3 as in the metal-air battery 30 shown in FIG. 10, the metal-air battery 30 can be configured not to use a liquid. The safety of 30 can be improved.
The solid electrolyte can be classified into an inorganic solid electrolyte or an organic solid electrolyte. Examples of the inorganic solid electrolyte include ion conductive ceramics, ion conductive glass, and ionic crystals. Examples of the organic solid electrolyte include an organic solid electrolyte in which an electrolyte salt (eg, zinc salt or lithium salt) is dispersed in a polymer compound (eg, polyethylene oxide), an ion exchange membrane, or the like. Examples of the ion exchange membrane include perfluorosulfonic acid, perfluorocarboxylic acid, styrene vinyl benzene, quaternary ammonium solid polymer electrolyte membrane (anion exchange membrane) and the like.
The electrolytic solution 3 can be stored in the battery case 32 or can be circulated in the battery case 32. The type of the electrolytic solution 3 is different depending on the type of the electrode active material contained in the metal electrode 5, but may be an electrolytic solution (aqueous electrolyte solution) using a water solvent.
For example, in the case of a zinc-air battery, a lithium-air battery, an aluminum-air battery, or an iron-air battery, an alkaline aqueous solution such as a sodium hydroxide aqueous solution or a potassium hydroxide aqueous solution can be used as the electrolyte solution 3. In the case of an air battery, the electrolyte solution 3 can be a neutral aqueous solution such as a sodium chloride aqueous solution.
Further, in a lithium air battery or a sodium air battery, a metal electrode containing lithium or sodium causes a violent reaction due to contact with water, and therefore an aqueous electrolyte solution can be used via an electrolyte membrane or the like.

Further, the electrolytic solution 3 may be stored in the second separator 14 inside the battery case 32. In this case, the 2nd separator 14 can be made into a bag shape, and the electrolyte solution 3 can be used as a gelatinization electrolyte solution. As a result, the electrolytic solution 3 can be stored in the second separator 14, and leakage of the electrolytic solution 3 from the second separator 14 can be suppressed. For example, in the metal-air battery 30 shown in FIGS. 6A and 6B, the gelled electrolyte 3 is stored in the second separator 14. Further, the electrolytic solution 3 in the second separator 14 may be a gelled electrolytic solution in which metal powder that is a negative electrode active material is mixed.
The electrolytic solution 3 may be injected into the battery case 32 or the second separator 14 after the metal electrode 5 is inserted into the battery case 32.

The battery case 32 of this embodiment is a component of the metal-air battery 30 and is a battery case that can accommodate the electrolyte 3 and the metal electrode 5. The battery case 32 may have a structure including the housing 1 and the air electrode 9. In this case, the housing 1 can have a container shape, and the air electrode 9 can be incorporated in the side wall portion of the container-shaped housing 1.
The battery case 32 may contain the electrolyte 3 as an electrolytic solution tank, and may contain the second separator 14 containing the electrolyte 3 inside the battery case 32. Moreover, the battery case 32 has a structure in which the metal electrode 5 or the 2nd separator 14 can be installed so that extraction is possible. Specifically, the battery case 32 can have a metal electrode insertion port, and the metal electrode 5 and the second separator 14 included in the metal electrode cartridge 20 can be inserted into the battery case 32 from the metal electrode insertion port. It is provided as follows.

The battery case 32 may be an electrolytic cell for storing or circulating the electrolyte solution 3. Moreover, the battery case 32 can have an electrolyte solution chamber. Further, when the electrolytic solution 3 is a gelled electrolytic solution, the battery case 32 may be an electrolytic cell that accommodates the gelled electrolytic solution. The battery case 32 may have a plurality of electrolyte chambers.
Further, the housing 1 included in the battery case 32 may have a structure in which a plurality of members are combined. Moreover, the housing | casing 1 may have rigidity. As a result, the metal-air battery 32 can be easily handled. Moreover, when the housing | casing 1 is comprised from a some member, a some member may have rigidity, respectively.

  The material of the housing 1 is not particularly limited as long as the material has corrosion resistance to the electrolytic solution. For example, polyvinyl chloride (PVC), polyvinyl alcohol (PVA), polyvinyl acetate, ABS resin, vinylidene chloride, polyacetal Polyethylene, polypropylene, polyisobutylene, polyphenylene ether, polystyrene, fluororesin, epoxy resin, or a hybrid resin thereof.

The battery case 32 includes the deformation mechanism 12 that changes the interval between the opposing side walls. The air electrode 9 is provided on the side wall, and the metal electrode 5 is provided between the opposing side walls. Therefore, the distance i between the metal electrode 5 and the air electrode 9 (hereinafter referred to as the electrode distance i) can be changed by changing the distance between the opposing side walls by the deformation mechanism 12. The deformation mechanism 12 can be provided in the housing 1 constituting the battery case 32 or the like.
The electrode interval i refers to the interval between the main surface of the metal electrode 5 and the main surface of the air electrode 9 facing this surface. For example, when the main surface of the metal electrode 5 and the main surface of the air electrode 9 are substantially parallel as in the metal-air battery 30 shown in FIGS. The distance between the major surfaces. Further, for example, when the main surface of the metal electrode 5 and the main surface of the air electrode 9 are not parallel as in the metal-air battery 30 shown in FIG. 8, the shortest distance between the two main surfaces is the electrode interval i.

Although the deformation | transformation mechanism 12 will not be specifically limited if it is a mechanism which can deform | transform the battery case 32 and can change the electrode space | interval i, For example, the expansion-contraction structure 16 and the shaft rotation structure may be sufficient. When the metal-air battery 30 has a plurality of electrode intervals i, the deformation mechanism 12 only needs to change at least one electrode interval i among the plurality of electrode intervals i.
As the elastic structure 16 that is the deformation mechanism 12, for example, the housing 1 is composed of a first housing 1a and a second housing 1b, and a part of the first housing 1a is placed inside the second housing 1b. A telescopic structure (nested structure) entering the provided space can be mentioned. In the telescopic structure 16, for example, the housing 1 is composed of a first housing 1 a and a second housing 1 b, the second housing 1 b has a guide portion, and the first housing 1 a serves as the guide portion. A structure (cantilever structure) that expands and contracts by being guided and moved, a lattice structure, a bellows structure 39, or a laminated slide structure may be used.

For example, in the metal-air battery 30 shown in FIGS. 1 to 3, FIGS. 5A and 5B, and FIGS. 6A and 6B, the case 1 is composed of a first case 1 a and a second case 1 b. The second housing 1b has an internal space, and a part of the first housing 1a has a telescopic structure 16 (telescopic structure) that enters the internal space. 1 to 3 and the like show the stretchable structure 16 only at the bottom of the battery case 32, the stretchable structure 16 is also provided at the side of the battery case 32.
Further, for example, in the metal-air battery 30 shown in FIGS. 4A and 4B, the housing 1 has a bellows structure 39.
1, FIG. 4 (a), FIG. 5 (a), and FIG. 6 (a) are schematic cross-sectional views of the metal-air battery 30 in a state where the battery case 32 is deformed so that the electrode interval i is narrowed. is there.
FIG. 2 is a schematic cross-sectional view of the metal-air battery 30 in a state where the metal-air battery 30 shown in FIG. 1 is deformed so that the electrode interval i is wide. FIG. FIG. 3 is a schematic cross-sectional view of a battery case 32 and a metal electrode cartridge 20 when replacing 30 metal electrode cartridges 20. FIG. 4B is a schematic cross-sectional view of the metal-air battery 30 in a state in which the metal-air battery 30 shown in FIG. 4A is deformed so that the electrode interval i is wide, and FIG. FIG. 6A is a schematic cross-sectional view of the metal-air battery 30 in a state where the metal-air battery 30 shown in FIG. 5A is deformed so that the electrode interval i is wide, and FIG. 2 is a schematic cross-sectional view of the metal-air battery 30 in a state where the metal-air battery 30 shown in FIG.

For example, as shown in FIGS. 7 and 8, the shaft rotation structure that is the deformation mechanism 12 includes a housing 1 that includes a first housing 1 a and a second housing 1 b, and the first housing 1 a and the second housing 1 b. A structure in which the rotating shaft 25 is provided at a connection portion with the housing 1b and the housing 1 is deformed by the second housing 1b rotating with respect to the first housing 1a may be employed. Further, the first housing 1a and the second housing 1b may be connected by an elastic structure 16 such as a bellows structure. This stretchable structure 16 can be provided so that it can be stretched and contracted with the rotational movement of the shaft. The rotating shaft 25 may be a part of the housing 1 or may be a member different from the housing 1.
The 1st housing | casing 1a and the 2nd housing | casing 1b may be connected by both the connection location which can be removed, and the rotating shaft 25. FIG. As a result, the connecting portion can be removed, and the housing 1 can be deformed so that the second housing 1b is rotated in the first rotation direction relative to the first housing 1a to increase the electrode interval i. Further, the second housing 1b is rotated in the second rotation direction with respect to the first housing 1a, and the housing 1 is deformed so that the electrode interval i is narrowed. The housing 1b can be connected. With such a configuration, the shape of the metal-air battery 30 in a state where the battery case 32 is deformed so that the electrode interval i is narrowed can be stabilized, and can be stably discharged.
The detachable connection location may be, for example, a structure in which a convex portion provided in one of the first housing 1a and the second housing 1b fits into a concave portion provided in the other. Moreover, the structure which provides a magnet in the 1st housing | casing 1a and the 2nd housing | casing 1b respectively, and the 1st and 2nd housing | casing 1a, 1b connects by the attractive force of a magnet may be sufficient.
For example, in the metal-air battery 30 shown in FIGS. 7 to 10, the casing 1 is composed of a first casing 1a and a second casing 1b, and the lower portion of the outer surface of the first casing 1a and the second casing 1b. A rotating shaft 25 is provided at a joint with the lower part of the inner side surface of the first casing 1a, and the second casing 1b can rotate with respect to the first casing 1a. Moreover, you may provide the expansion-contraction structure which connects the 1st housing | casing 1a and the 2nd housing | casing 1b to the side surface of the battery case 32. FIG.
7A, 7B, and 10A, 10B are a schematic cross-sectional view and a schematic side view of the metal-air battery 30 in a state where the battery case 32 is deformed so that the electrode interval i is narrowed. It is.
FIGS. 8A and 8B are a schematic cross-sectional view and a schematic side view of the metal-air battery 30 in a state where the metal-air battery 30 shown in FIGS. 7A and 7B is deformed so that the electrode interval i is widened. FIG. 9 is a schematic cross-sectional view of the metal-air battery 30 when the metal electrode cartridge 20 of the metal-air battery 30 shown in FIGS. 8A and 8B is replaced.

As shown in FIG. 1, FIG. 4 (a), FIG. 5 (a), FIG. 6 (a), FIG. 7 (a) (b), FIG. 10 (a) (b), and FIG. In a state where the battery case 32 is deformed so as to be narrow, the metal-air battery 30 can be discharged. As a result, the distance between the anode and the cathode can be shortened, and the ion conduction resistance can be reduced. As a result, the output characteristics of the metal-air battery 30 can be improved.
Further, the second separator 14 can be provided in contact with the first separator 15 in a state where the battery case 32 is deformed so that the electrode interval is narrowed. As a result, the distance between the anode and the cathode can be stabilized. When the second separator 14 is not provided, the metal electrode 5 can be provided in contact with the first separator 15 in a state where the battery case 32 is deformed so that the electrode interval is narrowed. When the first separator 15 is not provided, the second separator 14 can be provided in contact with the air electrode 9 in a state where the battery case 32 is deformed so that the electrode interval is narrowed.

The second separator 14 can be provided in close contact with the first separator 15 in a state where the battery case 32 is deformed so that the electrode interval is narrowed. Further, the second separator 14 may be in close contact with the metal electrode 5. Thus, the electrode interval i can be substantially the sum of the thickness of the second separator 14 and the thickness of the first separator 15, and the anode-cathode distance can be stabilized. As a result, the discharge characteristics of the metal-air battery 30 can be improved. In addition, since the second separator 14 can be firmly held by the first separator 15, the reliability of the metal-air battery 30 can be improved.
In these cases, the material of the first and second separators 15 and 14 can be an insulating porous material.
Even if the second separator 14 and the first separator 15 are brought into contact with each other at the time of discharge, if the battery case 32 is deformed so that the electrode interval i is widened, the second separator 14 and the first separator 15 are not in contact with each other. Therefore, it is possible to prevent the second separator 14 and the first separator 15 from being worn when the metal electrode cartridge 20 is taken out, and to prevent the metal-air battery 30 from being damaged.

  2, 3, 4 (b), 5 (b), 6 (b), 8 (a), (b), and FIG. 9, the battery case 32 so that the electrode interval i is widened. In the deformed state, the metal electrode 5 can be taken out from the battery case 32 and the metal electrode 5 can be inserted into the battery case 32. Thereby, the metal electrode 5 or the second separator 14 can be prevented from coming into contact with the air electrode 9 or the first separator 15, and the metal electrode 5 can be taken out and inserted. As a result, the metal air battery 30 can be prevented from being damaged when the metal electrode 5 is taken out and inserted, and the life characteristics of the metal air battery 30 can be improved. Even when the metal electrode 5 expands, the metal electrode 5 can be easily taken out from the battery case 32.

When the battery case 32 is an electrolytic solution tank, the battery case 32 may be provided so that the capacity of the electrolytic solution tank is changed by the deformation of the battery case 32. For example, in the metal-air battery 30 in which the battery case 32 is deformed so that the electrode interval i in FIG. 1 is narrow, the capacity of the battery case 32 is small, but the battery case so that the electrode interval i in FIG. In the metal-air battery 30 in a state where 32 is deformed, the capacity of the battery case 32 is large.
Thus, the water level of the electrolytic solution 3 can be changed by changing the capacity of the battery case 32 as the battery case 32 is deformed. Accordingly, when the electrode interval i is widened and the metal electrode 5 is inserted or removed, the water level of the electrolytic solution 3 is made lower than that of the metal electrode 5 as in the metal-air battery 30 shown in FIG. The amount of the electrolytic solution 3 attached to the metal electrode 5 or the second separator 14 can be reduced. Thereby, the leakage of the electrolyte solution 3 accompanying the replacement of the metal electrode 5 can be suppressed.
Further, in the metal-air battery 30 in a state where the battery case 32 is deformed so that the electrode interval i is wide, the water level of the electrolytic solution 3 may be positioned below the metal electrode 5. Thereby, the leakage of the electrolyte solution 3 accompanying the replacement of the metal electrode 5 can be suppressed.
Further, like the metal-air battery 30 shown in FIG. 1, the battery case 32 is deformed, the electrode interval i is narrowed, and the water level of the electrolytic solution 3 is made higher than that of the metal electrode 5. The electrolyte solution 3 can be supplied between the two and the metal-air battery 30 can be discharged.

The metal-air battery 30 may have a deformation assist structure that assists the deformation of the battery case 32. As a result, the battery case 32 can be stably deformed. Moreover, it can suppress that the battery case 32 is damaged.
The deformation assisting structure is not particularly limited as long as it can assist the deformation of the battery case 32. For example, two deformation assisting members like the deformation assisting members 24a and 24b included in the metal-air battery 30 shown in FIG. 24a and 24b are connected by the rotating shaft 25a, one deformation | transformation auxiliary member 24a is connected to the 1st housing | casing 1a by the rotating shaft 25b, and the other deformation | transformation auxiliary member 24b is connected to the 2nd housing | casing 1b by the rotating shaft 25c. The structure may be different. According to such a deformation assisting structure, it is possible to assist the deformation of the battery case 32 by a rotational motion about the rotation shafts 25a, 25b, and 25c. Further, by pulling a portion where the rotation shaft 25a is provided, the battery case 32 can be deformed so that the electrode interval i is narrowed, and by pressing a portion where the rotation shaft 25a is provided, the electrode interval i is reduced. The battery case 32 can be deformed to be wide.
In FIG. 5, the deformation assisting structure is provided at the lower part of the metal air battery 30, but the deformation assisting structure may be provided at the side of the metal air battery 30 or at the upper part of the metal air battery 30. May be.

  For example, the deformation assisting structure is provided with a spring 40 so as to be sandwiched by the housing 1 like the spring 40 and the deformation preventing member 42 included in the metal-air battery 30 shown in FIG. 4, and uses the elasticity of the spring 40. And the structure which assists the deformation | transformation of the battery case 32 may be sufficient. In this case, a deformation preventing member 42 that prevents deformation of the battery case 32 when the spring 40 is contracted can be provided. According to such a deformation assisting structure, the deformation of the battery case 32 can be automated using the force of the spring 40.

  When the battery case 32 serves as an electrolytic solution tank, the metal-air battery 30 has a waterproof sheet 37 on the inner surface of the battery case 32, such as the metal-air battery 30 shown in FIGS. May be. Thereby, it can suppress that the electrolyte solution 3 leaks from the expansion-contraction structure 16 etc. which the battery case 32 has. In addition, the waterproof sheet 37 can be provided so that it may deform | transform with the deformation | transformation of the battery case 32 like FIG.

When the 2nd separator 14 becomes an electrolyte tank, the metal air battery 30 can have the press part 21 which presses the 2nd separator 14 when the battery case 32 deform | transforms so that the electrode space | interval i may become narrow. Accordingly, the second separator 14 can be deformed by the pressing portion 21, the electrolytic solution 3 in the second separator 14 can be pushed upward, and the electrolytic solution 3 is placed between the metal electrode 5 and the air electrode 9. Can be supplied to. As a result, the metal-air battery 30 can be brought into a dischargeable state.
Further, the electrolytic solution 3 between the metal electrode 5 and the air electrode 9 can be lowered to the lower part of the second separator 14 by deforming the battery case 32 so that the electrode interval i becomes wider after the discharge. This can prevent the self-corrosion of the metal electrode 5 from proceeding.
The pressing portion 21 may be a part of the housing 1 or may be a member different from the housing 1.

For example, in the metal-air battery 30 shown in FIG. 6B, the electrolytic solution 3 is stored in the second separator 14, and the liquid level of the electrolytic solution 3 is lower than that of the metal electrode 5. In addition, pressing portions 21 a and 21 b are provided on both sides of the lower portion of the second separator 14. Then, when the battery case 32 is deformed so that the electrode interval i is narrow as in the metal-air battery 30 shown in FIG. 6A, the portion where the electrolyte 3 is stored below the second separator 14 is The electrolyte 3 in the second separator 14 is sandwiched between the pressing portions 21 a and 21 b and is pushed upward and supplied between the metal electrode 5 and the air electrode 9. And the metal air battery 30 will be in the state which can be discharged. Further, after the discharge, the battery case 32 is deformed so that the electrode interval i is wide as shown in FIG. 6B, so that the metal electrode 5 and the electrolytic solution 3 can be prevented from contacting each other. 5 can be prevented from proceeding. Moreover, when leaving the 2nd separator 14 in the battery case 32 and taking out the metal electrode 5 from the battery case 32, the leakage of the electrolyte solution 3 can be suppressed.
Further, in the metal-air battery 30 in a state where the battery case 32 is deformed so that the electrode interval i is widened, the upper part of the electrolytic solution 3 may be positioned below the metal electrode 5.

5. Metal electrode, second separator, metal electrode cartridge The metal electrode 5 is an electrode serving as an anode, and includes a metal that is an electrode active material of the anode. Moreover, the metal electrode 5 is provided in the battery case 32 so that extraction is possible.
The metal electrode 5 may be, for example, a metal plate containing a metal that is an electrode active material. The metal electrode 5 may include, for example, a metal electrode current collector 7 and an electrode active material layer 6 provided on the metal electrode current collector 7. The metal electrode 5 or the electrode active material layer 6 may be an electrodeposited metal or an aggregate containing metal powder.
When the metal electrode 5 or the electrode active material layer 6 is the aggregate, the aggregate may include the gelled electrolytic solution 3. In this case, the metal powder contained in the aggregate becomes the metal electrode 5 or the electrode active material layer 6, and the gelled electrolyte contained in the aggregate becomes the electrolyte 3. By setting it as such a structure, the interface of the metal electrode 5 and the electrolyte solution 3 can be enlarged, and the output of the metal air battery 30 can be enlarged.

  The metal electrode 5 or the electrode active material layer 6 may be porous. Thereby, the reaction surface area can be increased, and the output characteristics of the metal-air battery 30 can be improved. The porous electrode active material layer 6 can be formed by, for example, applying a mixture of metal powder, which is an electrode active material, a conductive material, and a binder on the metal electrode current collector 7 and performing pressing. it can. The conductive material can be preferably used to leave an electron conduction path even when a non-conductive film is formed on the surface layer of the metal powder that is the electrode active material and the conductivity is lowered, such as acetylene black, furnace black, channel Carbon black such as black and ketjen black, and conductive carbon particles such as graphite and activated carbon can be used. As the binder, polytetrafluoroethylene (PTFE) having excellent chemical resistance can be preferably used.

The electrode active material contained in the metal electrode 5 is, for example, a metal that generates a charge in the metal electrode 5 by an anodic reaction and dissolves in the electrolytic solution 3 as metal-containing ions. For example, in the case of a zinc-air battery, the electrode active material is metallic zinc, and zinc hydroxide or zinc oxide is deposited in the electrolytic solution 3. In the case of an aluminum-air battery, the electrode active material is metallic aluminum, and aluminum hydroxide is deposited in the electrolytic solution 3. In the case of an iron-air battery, the electrode active material is metallic iron, and iron oxide hydroxide or iron oxide is deposited in the electrolytic solution 3. In the case of a magnesium-air battery, the electrode active material is magnesium metal, and magnesium hydroxide is deposited in the electrolytic solution 3.
In the case of a lithium air battery, a sodium air battery, and a calcium air battery, the electrode active materials are metallic lithium, metallic sodium, and metallic calcium, respectively, and the electrolyte 3 contains oxides and hydroxides of these metals. Precipitates. In the case of a lithium air battery, a sodium air battery, or a calcium air battery, a solid electrolyte membrane may be provided between the metal electrode 5 and the electrolytic solution 3. Thereby, it can suppress that an electrode active material is corroded by electrolyte solution. In this case, the electrode active material is dissolved in the electrolytic solution after ion conduction through the solid electrolyte membrane.
The solid electrolyte that forms the solid electrolyte membrane can be classified into an inorganic solid electrolyte or an organic solid electrolyte. Examples of the inorganic solid electrolyte include ion conductive ceramics, ion conductive glass, and ionic crystals. Examples of the organic solid electrolyte include an organic solid electrolyte in which an electrolyte salt (for example, zinc salt or lithium salt) is dispersed in a polymer compound (for example, polyethylene oxide) or an ion exchange membrane. Examples of ion exchange membranes include solid polymer electrolyte membranes (anion exchange membranes) such as perfluorosulfonic acid, perfluorocarboxylic acid, styrene vinyl benzene, and quaternary ammonium.
In addition, an electrode active material is not limited to these examples, What is necessary is just what is generally used with the metal air battery. Moreover, although the electrode active material contained in the metal electrode 5 mentioned the metal which consists of a kind of metal element in said example, the electrode active material contained in the metal electrode 5 may be an alloy.
When the electrode active material is metallic zinc, the metal electrode 5 or the electrode active material layer 6 may include an additive material such as indium, bismuth, aluminum, or calcium. This can suppress the self-corrosion of the metal electrode 5 or the electrode active material layer 6.

The metal electrode current collector 7 has conductivity. The shape of the metal electrode current collector 7 is preferably a plate shape, a shape provided with a hole penetrating in the thickness direction of the plate, or an expanded metal or mesh. In addition, the metal electrode current collector 7 can be formed of, for example, a metal having corrosion resistance with respect to the electrolytic solution 3. The material of the metal electrode current collector 7 is, for example, nickel, gold, silver, copper, stainless steel or the like. The metal electrode current collector 7 may be a nickel-plated, gold-plated, silver-plated, copper-plated or tin-plated conductive substrate. For this conductive substrate, iron, nickel, stainless steel, or the like can be used.
As a result, the charge generated in the metal electrode 5 by the anode reaction can be collected by the metal electrode current collector 7, and the generated charge can be output to an external circuit. The electrode active material layer 6 may be fixed onto the main surface of the metal electrode current collector 7 by, for example, pressing metal particles or a lump as the electrode active material against the surface of the metal electrode current collector 7. Alternatively, a metal may be deposited on the metal electrode current collector 7 by a plating method or the like. In addition, regarding the shape of the metal electrode current collector 7, a plate shape is preferable from the viewpoint of conductivity when the electrode active material is deposited by a plating method, and when fixing metal particles or lump, From the viewpoint of preventing falling off, a plate provided with a through hole, or an expanded metal or mesh is preferable.
The metal electrode current collector 7 can be electrically connected to the metal electrode terminal 11. As a result, the charge generated in the metal electrode 5 via the metal electrode terminal 11 can be output to an external circuit. The metal electrode current collector 7 can also be electrically connected to a connector 48 that is electrically connected to the external connection terminal 45. Further, the metal electrode terminal 11 and the connector 48 may be electrically connected.

  The connector 48 is a connection part for electrically connecting the metal electrode 5 and the air electrode 9 to the external connection terminal 45. The connector 48 is provided so that at least one of the metal electrode 5 and the air electrode 9 is electrically connected to the external connection terminal 45 by deforming the battery case 32 so that the electrode interval i is narrowed. Further, the connector 48 deforms the battery case 32 so as to widen the electrode interval i, so that at least one of the metal electrode 5 and the air electrode 9 and the external connection terminal 45 are not electrically connected. Is provided. By providing such a connector 48, the discharge of the metal-air battery 30 can be started by deforming the battery case 32 so that the electrode interval i becomes narrow, and the battery case 32 so that the electrode interval i becomes wide. It is possible to stop the discharge of the metal-air battery 30 by deforming. This simplifies the operations associated with the start and stop of discharge. Further, malfunction of the metal-air battery 30 can be suppressed. Moreover, the safety of the metal-air battery 30 can be improved.

The connector 48 may be provided on the housing 1 or may be provided on the metal electrode cartridge 20.
FIG. 11A is a schematic top view of the metal-air battery 30 in a state where the battery case 32 is deformed so that the electrode interval i is narrowed, and FIG. 11B is shown in FIG. It is a schematic top view of the metal air battery 30 in a state in which the metal air battery 30 is deformed so that the electrode interval i is widened.
In the metal-air battery 30 shown in FIGS. 11A and 11B, a connector 48 is provided on the housing 1. The connector 48 is electrically connected to the air electrode terminal 10 a and the external connection terminal 45. The connector 48 includes a metal electrode socket 52 for electrical connection with the metal electrode terminal 11 and an air electrode socket 53 for electrical connection with the air electrode terminal 10b. The metal electrode terminal 11 has a metal electrode plug 50 for electrical connection with the metal electrode socket 52, and the air electrode terminal 10 b has an air electrode plug 51 for electrical connection with the air electrode socket 53. have.
As shown in FIG. 11B, in the metal-air battery 30 in which the battery case 32 is deformed so that the electrode interval i is widened, the metal electrode plug 50 and the air electrode plug 51 are the metal electrode socket 52 and the air electrode. Outside the socket 53, the metal electrode terminal 11 and the air electrode terminal 10b and the external connection terminal 45 are not electrically connected. Therefore, the discharge current cannot flow, and the discharge of the metal-air battery 30 is stopped.
As shown in FIG. 11A, in the metal-air battery 30 in a state where the battery case 32 is deformed so that the electrode interval i becomes narrow, the metal electrode plug 50 is inserted into the metal electrode socket 52, and the air electrode plug 51 is The air electrode terminal 10 and the external connection terminal 45 are electrically connected, and the metal electrode terminal 11 and the external connection terminal 45 are electrically connected. Therefore, the metal electrode 5 and the air electrode 9 and the external connection terminal 45 can be electrically connected, and the discharge current of the metal-air battery 30 can flow.

The metal electrode 5 can constitute the metal electrode cartridge 20 together with the lid member 35, the second separator 14, and the like. The metal electrode cartridge 20 may have a structure in which, for example, a metal electrode 5 is attached to a plate-like lid member 35 so as to be substantially perpendicular to the main surface of the lid member 35. By attaching the metal electrode cartridge 20 having such a T-shaped cross section to the battery case 32, the metal electrode 5 can be inserted into the battery case 32 using the cover member 35 as an operating portion and the cover member. The battery case 32 can be covered with 35. Further, when removing the metal electrode cartridge 20 from the battery case 32, the lid member 35 can be used as an operation portion. Thus, by replacing the metal electrode cartridge 20 included in the metal-air battery 30, the metal electrode 5 can be replaced, and the electrode active material can be supplied to the metal-air battery 30.
Further, the metal electrode cartridge 20 can be provided so that the second separator 14 remains in the battery case 32 and the metal electrode 5 can be taken out of the battery case 32. According to such a configuration, the replacement work of the metal electrode 5 can be simplified.

The metal electrode cartridge 20 may have a second separator 14 provided so as to accommodate the metal electrode 5. By providing the second separator 14, it is possible to suppress a leak current from flowing between the metal electrode 5 and the air electrode 9. Further, by providing the second separator 14, the metal electrode 5 and the air electrode 9 are prevented from being damaged when the metal electrode 5 is inserted into the battery case 32 or when the metal electrode 5 is taken out from the battery case 32. be able to. Further, by providing the second separator 14, it is possible to prevent the fine particles of the negative electrode active material and the negative electrode reaction product from adhering to the air electrode 9. Further, the second separator 14 may function as the electrolyte 3.
The second separator 14 can be fixed to the lid member 35, the metal electrode current collector 7, or the electrode active material layer 6 with, for example, a clip 17. The second separator 14 may be provided so as to be in contact with the metal electrode 5, or may be provided so that the electrolytic solution 3 is interposed between the second separator 14 and the metal electrode 5. When the second separator 14 functions as the electrolyte 3, the second separator 14 is provided in contact with the metal electrode 5. For example, the 2nd separator 14 can be provided like the metal air battery 30 shown in FIG.
Moreover, the 2nd separator 14 can be made into a bag shape. Thus, the second separator 14 can be used as an electrolytic bath in which the electrolytic solution 3 is accommodated, and the metal oxide deposited after the discharge can be removed together with the metal electrode cartridge 20 and collected. Furthermore, the bag-like second separator 14 can be freely repelled by the deformation mechanism 12 without repelling the pressure received from the side wall of the battery case 32 or the pressing portion 12 by shortening the interval between the opposing side walls of the battery case 32. The shape can be changed. Therefore, by making the 2nd separator 14 into a bag shape, the 2nd separator 14 and the air electrode 9 can be stuck, and ion conductivity can be improved. Furthermore, when the second separator 14 has a bag shape, the metal electrode cartridge 20 can be fixed by pressing from the side wall of the battery case 32.
If the second separator 14 is an electrolytic solution tank, both the metal electrode 5 and the electrolytic solution 3 can be replaced by replacing the metal electrode cartridge 20. Thereby, by exchanging the metal electrode cartridge 20, the electrolytic solution 3 whose metal-containing ion concentration is increased by the anode reaction can be taken out from the battery case 32, and a new electrolytic solution 3 can be supplied into the battery case 32. . Moreover, it is possible to prevent the electrolyte solution 3 from leaking when the metal electrode 5 is replaced.

The second separator 14 is not particularly limited as long as it has ion permeability and can suppress the permeation of fine particles of the negative electrode active material and the negative electrode reaction product. For example, the second separator 14 may be a porous resin film, a nonwoven fabric of resin fibers, or a molecular sieve. it can. The second separator 14 may have a stacked structure in which a plurality of separators are stacked. The second separator 14 may be an ion exchange membrane.
When the second separator 14 functions as the electrolyte 3, the material of the second separator 14 can be an ion exchange membrane such as an anion exchange membrane, a solid impregnated with an electrolyte, or a gel.
The material of the second separator 14 can be an insulating material. Further, the material of the second separator 14 may be a porous flexible material.
The material of the second separator 14 may be a porous rigid material. In this case, the second separator 14 can function as a support member for the metal electrode 5. For example, the electrode active material layer 6 can be provided on the second separator 14. Thus, the metal electrode current collector 7 can be omitted.
The material of the porous resin film or resin fiber nonwoven used for the second separator 14 can be an alkali-resistant resin, such as polyethylene, polypropylene, nylon 6, nylon 66, polyolefin, polyvinyl acetate, polyvinyl alcohol. Examples thereof include polytetrafluoroethylene (PTFE). The pore size of the pores of the second separator 14 is not particularly limited, but is preferably 30 μm or less. The second separator 14 is preferably subjected to a hydrophilic treatment so that the flow of the electrolytic solution 3 is improved.
Further, a gelled electrolyte may be introduced into the pores of the second separator 14. Thereby, when the 2nd separator 14 is used as an electrolytic solution tank, the leakage of the electrolytic solution 3 can be suppressed.
Examples of ion exchange membranes used for the second separator 14 include solid polymer electrolyte membranes (anion exchange membranes) such as perfluorosulfonic acid, perfluorocarboxylic acid, styrene vinylbenzene, and quaternary ammonium. Can be mentioned.
Further, a molecular sieve can be used for the second separator 14. As the molecular sieve, regardless of an organic material or an inorganic material, a substance having a property of separating substances according to the size of each substance such as a target molecule or ion can be used. The molecular sieve is not particularly limited as long as it is a general molecular sieve. For example, organic materials such as agar, agarose, polyacrylamide, polyacrylic acid, carboxymethylcellulose, natural zeolite containing oxides of sodium, silicon, and aluminum, An inorganic material such as a synthetic zeolite material, or an organic material, a material based on an inorganic material and cross-linked or element-substituted with various materials can be used. In addition, the molecular sieve preferably has pores that do not allow the metal oxide deposited during discharge to permeate, and particularly preferably has pores having a pore diameter of 1 μm or less.

When discharged by the metal-air battery 30, the electrode active material contained in the metal electrode 5 generates an electric charge in the metal electrode 5 by the anodic reaction and dissolves in the electrolytic solution 3 as metal-containing ions. For this reason, the electrode active material contained in the metal electrode 5 is gradually consumed as the anode reaction proceeds. When the electrode active material contained in the metal electrode 5 decreases, the charge generated in the metal electrode 5 decreases and the metal electrode 5 is used. By discharging the used metal electrode 5 from the battery case 32 and inserting a new metal electrode 5 into the battery case 32, the discharge by the metal-air battery 30 can be continued.
The charge generated in the metal electrode 5 is output to the outside as a discharge current and then used for the cathode reaction in the air electrode 9.

  When the concentration of the metal-containing ions generated in the electrolytic solution 3 by the anodic reaction exceeds the saturation concentration, the metal-containing ions may be precipitated in the electrolytic solution 3 as fine particles of metal oxide or metal hydroxide. Further, when the concentration of the metal-containing ions reaches the passive film forming concentration, the metal-containing ions may be deposited on the surface of the metal electrode 5 as a passive film of metal oxide or metal hydroxide. Therefore, the negative electrode reaction product may be deposited as fine particles floating in the electrolytic solution or settled on the bottom of the battery case 32, or may be deposited as a passive film attached on the surface of the metal electrode 5.

When the negative electrode reaction product is precipitated as fine particles and the fine particles are excessively present in the electrolytic solution 3, the fine particles of the negative electrode reaction product adhere to the pores of the porous air electrode 9, thereby preventing the diffusion of oxygen gas. As a result of the fine particles of the negative electrode reaction product adhering to the pores of the separators 14 and 15, the ion conduction path of OH ⁻ ions is hindered, resulting in a decrease in the output of the metal-air battery 30. For this reason, when fine particles of the negative electrode reaction product accumulate in the electrolytic solution 3, it is necessary to remove the fine particles from the electrolytic solution 3.
When the negative electrode reaction product is deposited as a passive film and this passive film covers most of the surface of the metal electrode 5, the anode reaction on the surface of the metal electrode 5 is inhibited, and the output of the metal-air battery 30 is reduced. For this reason, it is possible to continue the discharge by the metal-air battery 30 by removing the metal electrode 5 whose surface is covered with the passive film from the battery case 32 and inserting a new metal electrode 5 into the battery case 32.

6). Air electrode, air electrode current collector, first separator The air electrode 9 is a porous electrode serving as a cathode containing an air electrode catalyst. The air electrode 9 is provided on at least one of the opposing side walls of the battery case 32. For this reason, both the water contained in the electrolyte solution in the battery case 32 and the oxygen gas contained in the atmosphere outside the battery case 32 can be supplied to the air electrode. Further, hydroxide ions generated at the cathode can be conducted into the battery case 32. The air electrode 9 can be provided on both opposing side walls of the battery case 32.
The air electrode 9 may be provided on a side wall that partitions the electrolyte chamber provided in the battery case 32. Further, the air electrode 9 can be provided on the side wall of the battery case 32 by incorporating the air electrode 9 into the side wall of the container-shaped housing 1.

The air electrode 9 may have a porous gas diffusion layer and a porous air electrode catalyst layer provided on the gas diffusion layer. Further, a gel layer may be disposed in the pores of the air electrode 9.
In the air electrode 9, water supplied from the electrolytic solution 3 and the like, oxygen gas supplied from the atmosphere, and electrons react on the air electrode catalyst to generate hydroxide ions (OH ⁻ ) (cathode reaction). That is, the cathode reaction proceeds at the three-phase interface of the air electrode 9.
The air electrode 9 is provided so that oxygen gas contained in the atmosphere can diffuse into the air electrode 9. For example, the air electrode 9 can be provided so that at least a part of the surface of the air electrode 9 is exposed to the atmosphere. For example, a hole 23 may be provided in the housing 1 outside the air electrode 9 so that oxygen gas in the atmosphere can diffuse into the air electrode 9 through the hole 23. Further, an air flow path may be provided outside the air electrode 9 so that oxygen gas contained in the air flowing through the air flow path can diffuse into the air electrode 9. In this case, humidified air may be supplied to the air flow path, and water may be supplied to the air electrode 9 from the air flow path.

The air electrode catalyst layer may include, for example, a conductive porous carrier and an air electrode catalyst supported on the porous carrier. This makes it possible to form a three-phase interface in which oxygen gas, water, and electrons coexist on the air electrode catalyst, thereby allowing the cathode reaction to proceed. The air electrode catalyst layer may contain a binder. Moreover, you may arrange | position the gel layer formed by gelatinizing water or electrolyte solution in the pore of an air electrode catalyst layer.
The air electrode 9 composed of the air electrode catalyst layer and the gas diffusion layer may be produced by applying a porous carrier carrying the air electrode catalyst to a conductive porous substrate (gas diffusion layer). Good. For example, the air electrode 9 can be produced by applying carbon carrying an air electrode catalyst to carbon paper or carbon felt. This gas diffusion layer may function as an air electrode current collector. The gas diffusion layer may be composed of carbon fibers and a microporous layer made of carbon black and a water repellent polymer. The water repellent polymer is, for example, polytetrafluoroethylene (PTFE). This water-repellent polymer is provided to prevent leakage of the electrolyte solution 3 and has a gas-liquid separation function. That is, the electrolytic solution 3 is prevented from leaking from the battery case 32 and does not hinder the supply of oxygen gas to the air electrode catalyst layer.
The thickness of the air electrode 9 can be, for example, not less than 300 μm and not more than 3 mm.
The air electrode 9 can be electrically connected to the air electrode terminal 10. As a result, the charge generated at the air electrode 9 can be taken out to the external circuit.

The metal-air battery 30 may include an air electrode current collector 8 that collects charges generated in the air electrode 9. As a result, the charge generated in the air electrode 9 can be taken out to an external circuit efficiently, that is, with low resistance. The air electrode current collector 8 can be electrically connected to the air electrode terminal 10. Further, the air electrode current collector 8 may be electrically connected to the connector 48.
The material of the air electrode current collector 8 is not particularly limited as long as it has corrosion resistance with respect to the electrolytic solution 3, and examples thereof include nickel, gold, silver, copper, and stainless steel. Further, the air electrode current collector 8 may be a conductive base material subjected to nickel plating, gold plating, silver plating, or copper plating. For this conductive substrate, iron, nickel, stainless steel, or the like can be used.
Further, the shape of the air electrode current collector 8 may be a shape having a plurality of openings such as a plate shape, a mesh shape, and a punching metal. The plurality of openings of the air electrode current collector 8 may be open to the atmosphere. Thereby, oxygen gas in the atmosphere can be supplied to the air electrode 9 through the opening.
In addition, as a method of joining the air electrode current collector 8 to the porous carrier or the conductive porous substrate (gas diffusion layer), a method of bonding by screwing through a frame, or a conductive adhesive can be used. The method of using and combining is mentioned.

The air electrode 9 included in one cell 31 may be provided only on one side of the metal electrode 5, or may be provided on both sides of the metal electrode 5 as shown in FIG.
Examples of the porous carrier contained in the air electrode catalyst layer include carbon black such as acetylene black, furnace black, channel black, and ketjen black, and conductive carbon particles such as graphite and activated carbon. In addition, carbon fibers such as vapor grown carbon fiber (VGCF), carbon nanotube, and carbon nanowire can also be used.
Examples of the air electrode catalyst include fine particles made of platinum, iron, cobalt, nickel, palladium, silver, ruthenium, iridium, molybdenum, manganese, lanthanum, these metal compounds, and alloys containing two or more of these metals. Can be mentioned. This alloy is preferably an alloy containing at least two of platinum, iron, cobalt, and nickel. For example, platinum-iron alloy, platinum-cobalt alloy, iron-cobalt alloy, cobalt-nickel alloy, iron-nickel alloy And iron-cobalt-nickel alloy.
The binder contained in the air electrode catalyst layer is, for example, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), or the like.
Further, the porous carrier contained in the air electrode catalyst layer may be subjected to a surface treatment so that a cationic group exists as a fixed ion on the surface thereof. As a result, hydroxide ions can be conducted on the surface of the porous carrier, so that the hydroxide ions generated on the air electrode catalyst can easily move.
The air electrode catalyst layer may have an anion exchange resin supported on a porous carrier. Thereby, since hydroxide ions can be conducted through the anion exchange resin, the hydroxide ions generated on the air electrode catalyst are easily moved.

The first separator 15 can be provided on the main surface of the air electrode 9 inside the battery case 32.
The first separator 15 can be provided on the main surface of the air electrode 9 inside the battery case 32. By providing the first separator 15, the electrolyte 3 can be prevented from leaking outside the metal-air battery 30 through the pores of the air electrode 9, and the safety of the metal-air battery 30 can be improved. Can do. Moreover, since the water contained in the electrolytic solution 3 penetrates into the air electrode 9 after passing through the first separator 15, it is possible to suppress excess water from being supplied to the air electrode 9. Further, by providing the first separator 15, it is possible to prevent the fine particles of the negative electrode active material and the negative electrode reaction product contained in the electrolytic solution 3 from adhering to the air electrode 9. Further, by providing the first separator 15, it is possible to suppress a leak current from flowing between the metal electrode 5 and the air electrode 9. Furthermore, by providing the first separator 15, the metal electrode 5 and the air electrode 9 are prevented from being damaged when the metal electrode 5 is inserted into the battery case 32 or when the metal electrode 5 is taken out from the battery case 32. be able to. Further, the first separator 15 may function as the electrolyte 3.
When the first separator 15 functions as the electrolyte 3, the first separator 15 is provided so as to contact the metal electrode 5 or the second separator 14. For example, the 1st separator 15 can be provided like the metal air battery 30 shown in FIG.

The first separator 15 is not particularly limited as long as it has ion permeability and can suppress permeation of the fine particles of the negative electrode active material and the negative electrode reaction product. For example, the first separator 15 is, for example, a porous resin film, an ion exchange membrane, a resin fiber non-woven fabric or gel. It can be set as a hydrolyzed electrolyte film. The material of the first separator 15 can be an insulating material. The first separator 15 may have a stacked structure in which a plurality of separators are stacked.
When the first separator 15 functions as the electrolyte 3, the material of the first separator 15 can be an ion exchange membrane such as an anion exchange membrane or a solid, gel, or polymer molecular sieve impregnated with an electrolyte.
The material of the porous resin film or resin fiber nonwoven fabric used for the first separator 15 can be an alkali-resistant resin, such as polyethylene, polypropylene, nylon 6, nylon 66, polyolefin, polyvinyl acetate, polyvinyl alcohol. Examples thereof include polytetrafluoroethylene (PTFE). The pore size of the pores of the first separator 15 is not particularly limited, but is preferably 30 μm or less. The first separator 15 is preferably subjected to a hydrophilic treatment so as to improve the flow of the electrolytic solution. Further, a gelled electrolyte may be introduced into the pores of the first separator 15.
Examples of the ion exchange membrane used in the first separator 15 include perfluorosulfonic acid, perfluorocarboxylic acid, styrene vinylbenzene, and quaternary ammonium solid polymer electrolyte membranes (anion exchange membranes). It is done.
As the first separator 15, a molecular sieve can be used as in the second separator 14.

  1: Housing 1a: First Housing 1b: Second Housing 3: Electrolyte or Electrolyte 5: Metal Electrode 6: Electrode Active Material Layer 7: Metal Electrode Current Collector 8: Air Electrode Current Collector 9: Air Electrode 10, 10a, 10b: Air electrode terminal 11: Metal electrode terminal 12: Deformation mechanism 14: Second separator 15: First separator 16: Expandable structure 17: Clip 19: Seal member 20: Metal electrode cartridge 21, 21a, 21b: Press part 23: Hole 24, 24a, 24b: Deformation auxiliary member 25, 25a, 25b, 25c: Rotating shaft 30: Metal-air battery 31: Cell 32: Battery case 35: Lid member 37: Waterproof sheet 39: Bellows structure 40 : Spring 42: Deformation prevention member 45: External connection terminal 46: Electric cord 48: Connector 50: Metal pole plug 51: Air electrode plug 52: Metal electrode socket 53: Air electrode socket

Claims (9)

A first and second air electrode, and a deformation mechanism for changing the distance between the first and second side walls facing each other,
The first air electrode is incorporated into the first side wall , the second air electrode is incorporated into the second side wall,
The deformation mechanism is provided so as to change a distance between the first and second side walls in a state where the first air electrode is incorporated in the first side wall and the second air electrode is incorporated in the second side wall. Tank.   The battery case according to claim 1, wherein the deformation mechanism includes a telescopic structure. A pressing portion is provided on at least one of the opposing first and second side walls,
3. The battery case according to claim 1 , wherein the pressing portion is provided so as to press the electrolyte in the battery case by narrowing a distance between the first and second side walls facing each other.   The battery case according to any one of claims 1 to 3, wherein the deformation mechanism has a rotation shaft and is deformed with rotation about the rotation shaft. The battery case as described in any one of Claims 1-4 further equipped with the 1st separator which covers the inner surface of a 1st or 2nd air electrode.   A metal-air battery comprising the battery case according to any one of claims 1 to 5, an electrolyte contained in the battery case, and a metal electrode contained in the battery case. The battery case according to any one of claims 1 to 5, and a metal electrode cartridge at least a part of which is accommodated in the battery case,
The metal electrode cartridge is a metal-air battery comprising a metal electrode and a second separator containing an electrolyte.   The metal-air battery according to claim 7, wherein the second separator has a bag shape. Further provided with an external connection terminal,
The external connection terminals, by narrowing the interval between the first and second sidewalls said opposed, provided to at least one electrically connected among said metal electrode and the first and second air electrode The metal-air battery according to any one of claims 6 to 8.