JP2014139880A - Separator for alkaline electrolyte secondary battery, alkaline electrolyte secondary battery, and method for manufacturing alkaline electrolyte secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a separator for an alkaline electrolyte secondary battery, which can prevent a micro short circuit and damages of a separator upon manufacturing (assembling) an alkaline electrolyte secondary battery, and to provide an alkaline electrolyte secondary battery and a method for manufacturing an alkaline electrolyte secondary battery using the above separator for an alkaline electrolyte secondary battery.SOLUTION: A polymeric compound soluble with an alkaline electrolyte is deposited on a porous separator so as to once clog pores of the porous separator by the polymeric compound, which reduces such a risk that a fiber collector such as a carbon fiber penetrates the porous separator. By depositing the polymeric compound, physical strength of the separator is also increased, which prevents breakage by a protrusion of an electrode. After a secondary battery is assembled, the polymeric compound is dissolved in the electrolyte and eliminated from the pores of the separator.

Description

  The present invention relates to a porous separator in which a polymer compound soluble in an alkaline electrolyte is supported, an alkaline electrolyte secondary battery including such a porous separator, and a method for producing an alkaline electrolyte secondary battery.

  Secondary batteries are widely used as power sources for various portable devices, stationary power sources for emergency power generation, or moving power sources. As the secondary battery, a lead storage battery, a nickel-cadmium battery, a nickel-hydrogen battery, or a lithium ion battery is representative. As a secondary battery using an alkaline electrolyte, a nickel-hydrogen battery is typical, and a nickel-cadmium battery or a nickel-zinc battery is also used.

  The separator of the alkaline electrolyte secondary battery needs to be porous in order to make the secondary battery hermetically sealed, and is usually made of an inexpensive polyolefin nonwoven fabric that is excellent in oxidation resistance and alkali resistance. Polyolefin nonwoven fabrics are generally hydrophilic because they are produced using a surfactant. However, when a non-woven fabric made of polyolefin is incorporated in a secondary battery as a separator and charging and discharging are repeated, there is a problem in that the hydrophilicity is lowered due to the alteration of the surfactant, the electrolyte retention is lost, and the battery characteristics are lowered. Therefore, in order to impart hydrophilicity to the polyolefin itself, hydrophilization treatment with fuming sulfuric acid or fluorine has been put into practical use (for example, Patent Document 1).

  On the other hand, the shape of the current collector (active material holder) of the electrode used in the alkaline electrolyte secondary battery is a porous body having a two-dimensional structure such as punching metal or a three-dimensional structure such as foam metal. Generally it is either. Therefore, a general alkaline electrolyte secondary battery includes a plate-like positive electrode, a separator, and a plate-like negative electrode.

  Furthermore, for the purpose of high output, rapid charge / discharge characteristics and long life, a fiber battery using a fiber having electronic conductivity as an electrode current collector, particularly a carbon fiber has been proposed (Patent Document 2 and Patent Document). 3). In the fiber electrode (mainly sheet-like) used in the fiber battery, each fiber current collector is covered with the active material layer, so the active material layer exists in a state very close to the current collector. As the diameter of the fiber current collector is smaller, the active material layer and the current collector are closer to each other. Thus, since the active material and the current collector are in intimate contact, the utilization factor of the active material is improved, rapid charge / discharge is possible, and the battery life is long.

JP 2007-207526 A JP 2003-317794 A JP 2010-225354 A

  In the manufacturing process of a fiber battery, when an electrode group is constituted by a fiber electrode (fiber positive electrode and / or fiber negative electrode) and a separator, and the electrode group is inserted into a battery case, a micro short circuit is rarely generated. This is because many fibers are used as a current collector as a fiber bundle, but when the fiber protrudes from the fiber bundle, if the electrode group is brought into close contact, the protruded fiber may penetrate the separator and reach the counter electrode. It is thought to be the cause.

  Batteries that use nickel fiber to produce a three-dimensional porous body and use this as a current collector have been developed. However, as with fiber batteries, there is a problem of short circuiting during battery assembly. The rest was not widely put into practical use.

  Also, when using foamed nickel or punched metal as a current collector, especially when assembling a wound battery, if the current collector's cut edge is protruding, the separator will still be damaged by the protrusion, causing a short circuit. It can be a cause.

  Furthermore, in a sealed battery using an alkaline electrolyte such as a nickel-hydrogen battery or a nickel-cadmium battery, the sealing is usually maintained by a reaction in which oxygen generated from the positive electrode during charging is returned to water at the negative electrode. However, when the charge / discharge cycle is repeated, the positive electrode and negative electrode active materials swell, so that the electrolyte in the separator is absorbed. As a result, the alkaline electrolyte in the separator is depleted, which is the main cause. Battery life is often shortened.

  Furthermore, when the sealed battery is assembled, if the fiber penetrates the separator or the separator is damaged by the protrusion, the alkaline electrolyte may leak from the separator, and the battery life may be significantly shortened.

  An object of this invention is to provide the separator for alkaline electrolyte secondary batteries which can prevent a micro short circuit and damage to a separator at the time of manufacture (assembly) of an alkaline electrolyte secondary battery. Moreover, this invention aims at provision of the alkaline electrolyte secondary battery which uses such a separator for alkaline electrolyte secondary batteries, and its manufacturing method.

  In particular, when manufacturing alkaline electrolyte secondary batteries using a fiber positive electrode and / or fiber negative electrode, the present inventors prevent a rare short circuit that occurs in a separator that is generated by repeated charge and discharge over a long period of time. We have made extensive studies on the means to suppress the electrolyte depletion. As a result, by supporting a polymer compound that is soluble in an alkaline electrolyte on the porous separator, the pores of the porous separator are blocked by the polymer compound, and the fiber current collector such as carbon fiber is porous. It has been found that the risk of penetrating the separator can be reduced.

  In addition, the present inventors improve the physical strength of the porous separator by supporting a polymer compound that is soluble in an alkaline electrolyte on the porous separator, and hardly cause damage due to the protrusions of the current collector. I found out that

  Further, the present inventors have disclosed that an alkaline electrolyte secondary battery including a porous separator having a polymer compound soluble in an alkaline electrolyte is dissolved in the porous separator, in which the polymer compound is eluted in the alkaline electrolyte. Even when it becomes a finished product (secondary battery) after the polymer compound is removed from the alkaline electrolyte, it is less likely to run out of alkaline electrolyte than a sealed secondary battery that uses a porous separator that does not support the polymer compound. As a result, the present invention has been completed.

Specifically, the present invention
The present invention relates to a separator for an alkaline electrolyte secondary battery, characterized in that a polymer compound soluble in an alkaline electrolyte is supported on a porous separator.

  The separator for an alkaline electrolyte secondary battery according to the present invention is a separator in which a polymer compound that is soluble in an alkaline electrolyte such as KOH, NaOH, or LiOH is supported on a porous separator. And the internal structure of the porous separator) is filled with the polymer compound. For this reason, even if the fiber protrudes from the fiber bundle, the protruding fiber hardly penetrates the separator. In addition, since the physical strength is improved as compared with the original porous separator, even a current collector other than the fiber current collector is less likely to be damaged by the protrusion of the current collector. Further, after the alkaline electrolyte secondary battery is completed, the polymer compound is eluted into the alkaline electrolyte and removed from the pores, so that the same function as the original porous separator can be exhibited.

  It is presumed that the polymer compound eluted from the porous separator does not dissolve and disperse evenly in the alkaline electrolyte, but dissolves in the alkaline electrolyte around the porous separator and increases the viscosity of the alkaline electrolyte. As a result, even when the porous separator is not damaged, it is possible to suppress the depletion of the alkaline electrolyte.

The present invention also provides
A plate-like or sheet-like positive electrode and a plate-like or sheet-like negative electrode are spirally wound through a porous separator carrying a polymer compound soluble in an alkaline electrolyte,
After inserting the wound positive electrode, negative electrode and separator into the battery case, the alkaline electrolyte is injected,
The present invention relates to a wound alkaline electrolyte secondary battery obtained by eluting a polymer compound supported on a porous separator into an alkaline electrolyte.

The present invention also provides
Laminating a plurality of plate-like or sheet-like positive electrodes and plate-like or sheet-like negative electrodes through a porous separator carrying a polymer compound soluble in an alkaline electrolyte, and crimping and fixing,
After inserting the fixed positive electrode, negative electrode and separator into the battery case, injecting alkaline electrolyte,
The present invention relates to a laminated alkaline electrolyte secondary battery obtained by eluting a polymer compound supported on a porous separator into an alkaline electrolyte.

  The porous separator is preferably a polyolefin nonwoven fabric.

  It is also preferable that the porous separator is a polyolefin microporous film.

  Polymer compounds soluble in the alkaline electrolyte include carboxymethylcellulose, hydroxymethylcellulose, hydroxypropylcellulose, methylcellulose, polyacrylic acid, polyethylene oxide, methylcellulose, polyacrylic acid, sodium polyacrylate, and acrylic acid and vinyl alcohol. A combination of one or more selected from the group consisting of copolymers is preferred.

The amount of the polymer compound soluble in the alkaline electrolyte supported on the porous separator is preferably 200 mg / m ² or more and 1000 mg / m ² or less.

  It is preferable that at least one of the positive electrode or the negative electrode is a fiber electrode.

The present invention further includes
A step of producing a porous separator carrying a polymer compound by immersing the porous separator in a polymer compound soluble in an alkaline electrolyte; and
Winding a plate-like or sheet-like positive electrode and a plate-like or sheet-like negative electrode in a spiral shape through a porous separator carrying a polymer compound soluble in an alkaline electrolyte;
Inserting the wound positive electrode, negative electrode, and separator into a battery case, and injecting an alkaline electrolyte;
Sealing the electrolytic cell;
The present invention relates to a method for manufacturing a wound alkaline electrolyte secondary battery.

The present invention further includes
A step of producing a porous separator carrying a polymer compound by immersing the porous separator in a polymer compound soluble in an alkaline electrolyte; and
A step of laminating a plurality of plate-like or sheet-like positive electrodes and plate-like or sheet-like negative electrodes via a porous separator carrying a polymer compound soluble in an alkaline electrolyte, and crimping and fixing;
Inserting the fixed positive electrode, negative electrode, and separator into the battery case, and injecting an alkaline electrolyte;
Sealing the electrolytic cell;
The present invention relates to a method for producing a laminated alkaline electrolyte secondary battery.

  According to the present invention, it is possible to prevent the occurrence of a short-circuit in the manufacturing process of the alkaline electrolyte secondary battery, and to prevent the battery life from being shortened by suppressing the depletion of the alkaline electrolyte.

The structure of the SubC type cylindrical nickel-hydrogen battery of an Example and a comparative example is shown.

  Embodiments of the present invention will be described including examples. The present invention is not limited to the following description.

<Porous separator>
The separator for the alkaline electrolyte secondary battery of the present invention is not particularly limited as long as it is a material having alkali resistance, electrolyte retention, and an appropriate pore size, but is excellent in oxidation resistance and alkali resistance. It is preferably made of polyolefin which is inexpensive, and particularly preferably made of hydrophilic polyolefin.

  The porous separator is preferably a polyolefin nonwoven fabric. The thickness of the porous separator itself is preferably about 80 to 200 μm. When used for secondary batteries that are not overcharged, such as emergency power supplies, as a porous separator, a thickness of 30 made of polyolefin, widely used in lithium ion secondary batteries, etc. A microporous membrane of about ˜50 μm may be used.

<Polymer compound>
The polymer compound is not particularly limited as long as it is soluble in an alkaline electrolyte, but specific examples of suitable polymer compounds are carboxymethyl cellulose, hydroxymethyl cellulose, hydroxypropyl cellulose, methyl cellulose, polyacrylic acid, polyethylene oxide, polyacrylic acid. , Sodium polyacrylate, or a copolymer of acrylic acid and vinyl alcohol. These polymer compounds may be used alone or in combination of two or more.

Loading of the polymer compound is preferably adjusted to 200 mg / m ² or more 1000 mg / m ² or less of the range with respect to the separator area. When an excessive polymer compound exceeding 1000 mg / m ² is supported, after the alkaline electrolyte secondary battery is manufactured, the viscosity of the electrolyte solution becomes too large due to the polymer compound eluted from the separator. There is a possibility that oxygen gas from the positive electrode passes through the separator. When the amount of the polymer compound supported exceeds 1000 mg / m ² , the thickness of the separator increases, which may make it difficult to insert the electrode group into the battery case. On the other hand, if it is less than 200 mg / m ² , the improvement of the physical strength of the separator due to the loading of the polymer compound is insufficient, and there is a possibility that the effect of preventing a micro short circuit due to the penetration of the fiber is insufficient.

<Alkaline electrolyte>
The alkaline electrolyte secondary battery of the present invention uses an electrolytic solution made of an alkaline aqueous solution. As the alkaline aqueous solution, an aqueous solution of KOH, NaOH or LiOH is suitable, and a mixed aqueous solution of two or more of these aqueous solutions can also be used. Among KOH, NaOH or LiOH aqueous solutions, the KOH aqueous solution has the highest ionic conductivity, and especially the 6-8N aqueous solution shows high conductivity. In order to suppress the generation of oxygen generated in competition with the charging reaction and improve the charging efficiency, it is effective to appropriately add NaOH or LiOH to the KOH aqueous solution. LiOH is highly effective in suppressing oxygen generation and improving charging efficiency, but the amount dissolved in an aqueous KOH solution is not so large. For applications that require improved charging efficiency, it is necessary to add not only LiOH but also NaOH to the aqueous KOH solution.

  In addition, in an alkaline electrolyte secondary battery, it is necessary to return oxygen generated from the positive electrode to water at the negative electrode during overcharge. Therefore, an open-type secondary battery that releases oxygen and hydrogen generated in the overcharge state with a valve On the other hand, it is a common practice to add the electrolytic solution so as to be impregnated in the separator and leave the pores through which oxygen gas passes in the separator.

<Fiber current collector>
The fiber used as the current collector of the fiber electrode may be a conductive fiber, but a carbon fiber that is excellent in oxidation resistance and alkali resistance and inexpensive in price is most preferable. Carbon fiber is not used as a current collector for a single fiber, but is used as a fiber group (fiber bundle) in which thin carbon fibers are bundled. The number of single fibers constituting the fiber group is 100 to several tens of thousands, and it is industrially preferable to open and use the fibers. The diameter of the surface of the single carbon fiber is not particularly limited, but is preferably 1 to 300 μm, and more preferably 5 to 100 μm.

<Alkaline electrolyte secondary battery>
In the present invention, since it is assumed that the polymer compound supported on the separator is soluble in an alkaline aqueous solution, the secondary battery is a nickel-hydrogen battery using nickel hydroxide as the positive electrode and a hydrogen storage alloy as the negative electrode. A main target is a nickel-cadmium battery or a nickel-zinc battery. The fiber electrode may be used as either the positive electrode or the negative electrode, or both electrodes. As a form of the secondary battery, both a wound type and a stacked type can be targeted.

[Example]
A nickel-hydrogen fiber battery using a fiber electrode was produced as the alkaline electrolyte secondary battery of the present invention.

(Preparation of separator for alkaline electrolyte secondary battery)
A polypropylene nonwoven fabric having a thickness of 130 μm and a porosity of about 50% was treated with fuming sulfuric acid to obtain a hydrophilic nonwoven fabric. This hydrophilic nonwoven fabric was immersed in a mixed solution in which the same amount of 1% by mass carboxymethylcellulose and 1% by mass sodium polyacrylate aqueous solution were mixed. After the hydrophilic nonwoven fabric was pulled up from the mixed solution, the mixed solution adhered between the rollers was removed. Then, it dried at 80 degreeC and produced the separator (Separator for alkaline electrolyte secondary batteries) which carry | supported the high molecular compound (carboxymethylcellulose and sodium polyacrylate) on the hydrophilic nonwoven fabric. The amount of the polymer compound supported on this separator calculated from the weight was about 600 mg / m ² .

(Production of fiber cathode)
A commercially available carbon fiber group consisting of about 10,000 carbon fibers having a diameter of 40 μm obtained from polyacrylonitrile was opened to a thickness of about 200 μm and a width of 30 mm. Thereafter, the carbon fiber was nickel-plated with a watt bath. The carbon fiber whose surface was nickel-coated was used as a current collector for the electrode. The thickness of the coated nickel was adjusted to 3 μm.

  In addition to nickel hydroxide spherical powder with an average pore size of 25 μm, each containing 5% by mass of cobalt and zinc in terms of metal, as an added amount with respect to the mass of nickel hydroxide, 0.5% by mass of carboxymethylcellulose as a thickener and as a binder 2% by mass of polyethylene emulsion (2% by mass as polyethylene weight) and 2% by mass of fluororesin were added, and a positive electrode slurry was prepared using a fluororesin dispersion. The current collector (nickel-coated carbon fiber) was immersed in this positive electrode slurry, and then the current collector was pulled up from the positive electrode slurry. The positive electrode active material layer was formed by drying the positive electrode slurry on the surface of the current collector.

(Fabric anode production)
An ingot having a composition of MmNi _3.9 Mn _0.45 Al _0.32 Co _0.73 was heat-treated at 1000 ° C. for 10 hours in an Ar gas atmosphere, and then pulverized to an average particle size of 20 μm. This was immersed in a 30% by weight aqueous potassium hydroxide solution (90 ° C.) for 20 minutes, washed with water, and then dried, MmNi5 alloy powder was used as a hydrogen storage alloy. To this MmNi5 alloy powder, 0.5% by mass of carboxymethylcellulose as a thickener and 3% by mass of styrene butadiene rubber (SBR) as a binder were added, and a slurry for negative electrode was prepared using a fluororesin dispersion. The same current collector (nickel-coated carbon fiber) as the positive electrode was immersed in this negative electrode slurry, and then the current collector was pulled up from the negative electrode slurry. The negative electrode slurry on the surface of the current collector was dried to form a negative electrode active material layer.

(Production of wound alkaline electrolyte secondary battery)
Both the positive electrode and the negative electrode were cut into a width of 30 mm and a length of 30 mm. The positive electrodes were made by stacking two sheets side by side so as to have a length of 250 mm and welding a nickel ribbon in the length direction. The negative electrode was produced by cutting to a width of 30 mm and a length of 30 mm, side by side to a length of 310 mm, and welding a nickel ribbon in the length direction. The positive electrode and the negative electrode have a structure in which terminals are taken out by a known tabless method. The capacity ratio (N / P) between the negative electrode and the positive electrode was 1.8 after confirming that the actual capacity density of the negative electrode alloy was 260 mAh / g.

  An electrode group was constructed using the above negative electrode, positive electrode, and separator, and this was wound to produce a SubC type cylindrical nickel-hydrogen battery. A positive electrode terminal was welded to the battery case lid, and a negative electrode terminal was welded to the bottom of the battery case, and the outer periphery of the electrode group was structured to be in contact with the negative electrode. The battery case is a cylindrical battery case with a diameter of 22 mm and a height of 43 mm. The material is nickel-plated steel. After inserting the electrode group into the battery case, an aqueous solution prepared by dissolving LiOH at a concentration of 30 g / L in a 7 mol KOK aqueous solution as an alkaline electrolyte was injected. After injecting the alkaline electrolyte, the battery case lid was sealed. The nominal capacity of the wound alkaline electrolyte secondary battery produced in this way was 3.5 Ah.

[Comparative example]
A SubC-type cylindrical nickel-hydrogen battery (a wound alkaline electrolyte secondary battery) was produced in the same manner as in the example except that the hydrophilic non-woven fabric was not used as a separator without supporting the polymer compound.

  FIG. 1 shows the structure of a SubC type cylindrical nickel-hydrogen battery of Examples and Comparative Examples. In FIG. 1, the code | symbol 1 is a positive electrode and the direction of a fiber is shown by the line. Reference numeral 1a denotes a positive electrode current collector plate, which is a so-called tabless system in which a foamed nickel plate is disposed on both sides of a fiber current collector and pressed, and a foamed nickel layer is formed on both sides of the fiber current collector by pressure bonding. . Reference numeral 2 denotes a negative electrode, and the direction of the fiber is indicated by a line as in the positive electrode 1. Reference numeral 2a denotes a negative electrode current collector plate. Like the positive electrode, a foamed nickel plate is arranged on both surfaces of the fiber current collector and pressed, and a foamed nickel layer is formed on both surfaces of the fiber current collector by pressure bonding. Yes.

  Reference numeral 3 denotes a separator. Although the alkaline electrolyte is not illustrated, most of the alkaline electrolyte is present in the separator 3, and a part thereof is contained in the active material of the positive electrode 1 and the negative electrode 2. Reference numeral 4 denotes a battery case, which is connected to the negative electrode 2. Reference numeral 5 denotes a lid, which is connected to the positive electrode 1.

<Comparison of battery capacity>
100 cells each of the SubC type cylindrical nickel-hydrogen batteries of Examples and Comparative Examples were produced. Each battery was subjected to 0.2C charge / discharge twice and 0.5C charge / discharge twice as chemical conversion. All batteries had 1C discharge with an average voltage of 1.25 V and a discharge capacity (end voltage 0.9 V) of 2.90 ± 0.3 Ah, and no difference in battery capacity was observed between the examples and the comparative examples.

<Rate of short-circuit occurrence>
Next, in order to confirm the presence or absence of a micro short-circuit, the batteries of Examples and Comparative Examples, each of 100 cells, were charged at 1 C, then left at an ambient temperature of 25 ° C. for 30 days, and then 1 C discharge was performed. As a result, all of the batteries of the examples maintained a battery capacity of 86% or more, whereas the batteries of the comparative examples had one cell whose battery capacity decreased to 74% and 76%.

  After this test, each battery was charged and discharged at 1 C 200 times. All of the batteries immediately after charging had an average voltage of 1.27 V at 1 C discharge and a discharge capacity (end voltage of 0.9 V) of 2.95 ± 0.3 Ah, and no difference was found between the examples and the comparative examples.

  After charging at 1C, it was left for 30 days at an ambient temperature of 25 ° C., after which 1C discharge was performed. As a result, all of the batteries of the examples maintained a battery capacity of 88% or more, whereas the batteries of the comparative examples had 1 cell with the battery capacity reduced to 73% and 75% as in the case immediately after the formation. There was one by one.

  From the above experimental results, it was inferred that a micro short circuit occurred at the time of battery assembly, and that the short circuit did not proceed even after repeated charge and discharge. In other words, it has been inferred that although there is no problem in applications in which normal charging and discharging are performed, battery capacity may be reduced in applications in which the battery is left after charging.

<Charge / discharge cycle life>
In the alkaline electrolyte secondary battery of the present invention, since the oxygen generated during overcharging from the positive electrode reaches the negative electrode, the amount of the electrolyte injected into the battery case is left so as to leave a hole where no electrolyte exists in the separator. Adjusted. For this reason, the diffusion of the electrolyte solution inside the battery is in a state that is suppressed to some extent. As a result, it is presumed that the polymer compound supported on the separator remains in the electrolyte solution near the separator and increases the viscosity.

  In a secondary battery using an alkaline electrolyte such as a nickel-hydrogen battery or a nickel-cadmium battery, it is considered that the electrolyte in the separator is depleted as a main cause of shortening the charge / discharge cycle life. In the alkaline electrolyte secondary battery of the present invention, it can be expected that electrolyte depletion in the separator is suppressed. (Total of 1,200 cycles of charging and discharging in the above test) was performed, and the capacity retention rate was examined. As a result, the average value of the battery of the example was 95% of the initial value, whereas the average value of the battery of the comparative example was 93%, and the battery of the example was charged and discharged more than the battery of the comparative example. It was confirmed that the cycle life was slightly improved.

  As described above, the separator for an alkaline electrolyte secondary battery of the present invention includes an alkaline electrolyte 2 provided with a conductive fiber group, preferably a carbon fiber group as a current collector, and a fiber electrode formed by forming an active material layer thereon. As a separator for a secondary battery, it is possible to prevent a minute short circuit caused by a fiber current collector that occurs extremely rarely during battery assembly. As a result, it has been clarified that the alkaline electrolyte secondary battery of the present invention having a fiber electrode exhibits an effect of bringing about a great reliability. Further, a slight improvement was observed in the charge / discharge cycle life.

  The separator for an alkaline electrolyte secondary battery of the present invention is particularly effective for an alkaline electrolyte secondary battery equipped with a fiber electrode, but is not limited to a three-dimensional foamed nickel current collector, punching metal or expanded metal. A battery including a two-dimensional current collector that shows a protruding structure by cutting is also effective as in a fiber battery.

  The separator for an alkaline electrolyte secondary battery, the alkaline electrolyte secondary battery, and the method for producing the alkaline electrolyte secondary battery of the present invention are very useful in the battery field.

1: positive electrode 1a: positive electrode current collector plate 2: negative electrode 2a: negative electrode current collector plate 3: separator (separator carrying a polymer compound)
4: Battery case 5: Lid

Claims (19)

  A separator for an alkaline electrolyte secondary battery, wherein a porous separator carries a polymer compound soluble in an alkaline electrolyte.   The alkaline electrolyte secondary battery separator according to claim 1, wherein the porous separator is a polyolefin nonwoven fabric.   The alkaline electrolyte secondary battery separator according to claim 1, wherein the porous separator is a polyolefin microporous film.   The polymer compound soluble in the alkaline electrolyte is carboxymethylcellulose, hydroxymethylcellulose, hydroxypropylcellulose, methylcellulose, polyacrylic acid, polyethylene oxide, methylcellulose, polyacrylic acid, sodium polyacrylate, and a copolymer of acrylic acid and vinyl alcohol. The separator for alkaline electrolyte secondary batteries according to any one of claims 1 to 3, wherein the separator is one or a combination of two or more selected from the group consisting of polymers. The separator for an alkaline electrolyte secondary battery according to any one of claims 1 to 4, wherein a loading amount of the polymer compound soluble in the alkaline electrolyte is 200 mg / m ² or more and 1000 mg / m ² or less. A plate-like or sheet-like positive electrode and a plate-like or sheet-like negative electrode are spirally wound through a porous separator carrying a polymer compound soluble in an alkaline electrolyte,
After inserting the wound positive electrode, negative electrode and separator into the battery case, an alkaline electrolyte is injected,
A wound alkaline electrolyte secondary battery obtained by eluting a polymer compound supported on a porous separator into an alkaline electrolyte.   The wound alkaline electrolyte secondary battery according to claim 6, wherein the porous separator is a polyolefin nonwoven fabric.   The wound alkaline electrolyte secondary battery according to claim 6, wherein the porous separator is a polyolefin microporous membrane.   The polymer compound soluble in the alkaline electrolyte is carboxymethylcellulose, hydroxymethylcellulose, hydroxypropylcellulose, methylcellulose, polyacrylic acid, polyethylene oxide, methylcellulose, polyacrylic acid, sodium polyacrylate, and a copolymer of acrylic acid and vinyl alcohol. The wound alkaline electrolyte secondary battery according to any one of claims 6 to 8, which is one or a combination of two or more selected from the group consisting of polymers. The wound alkaline electrolyte secondary battery according to any one of claims 6 to 9, wherein a supported amount of the polymer compound soluble in the alkaline aqueous electrolyte is 200 mg / m ² or more and 1000 mg / m ² or less. .   The wound alkaline electrolyte secondary battery according to any one of claims 6 to 10, wherein at least one of the positive electrode and the negative electrode is a fiber electrode. Laminating a plurality of plate-like or sheet-like positive electrodes and plate-like or sheet-like negative electrodes through a porous separator carrying a polymer compound soluble in an alkaline electrolyte, and crimping and fixing,
After inserting the fixed positive electrode, negative electrode and separator into the battery case, an alkaline electrolyte is injected,
A laminated alkaline electrolyte secondary battery obtained by eluting a polymer compound supported on a porous separator into an alkaline electrolyte.   The multilayer alkaline electrolyte secondary battery according to claim 12, wherein the porous separator is a polyolefin nonwoven fabric.   The multilayer alkaline electrolyte secondary battery according to claim 12, wherein the porous separator is a polyolefin microporous membrane.   The polymer compound soluble in the alkaline electrolyte is carboxymethylcellulose, hydroxymethylcellulose, hydroxypropylcellulose, methylcellulose, polyacrylic acid, polyethylene oxide, methylcellulose, polyacrylic acid, sodium polyacrylate, and a copolymer of acrylic acid and vinyl alcohol. The multilayer alkaline electrolyte secondary battery according to any one of claims 12 to 14, which is one or a combination of two or more selected from the group consisting of polymers. The multilayer alkaline electrolyte secondary battery according to any one of claims 12 to 15, wherein an amount of a polymer compound soluble in the alkaline electrolyte is 200 mg / m ² or more and 1000 mg / m ² or less.   The multilayer alkaline electrolyte secondary battery according to any one of claims 12 to 16, wherein at least one of the positive electrode and the negative electrode is a fiber electrode. A step of producing a porous separator carrying a polymer compound by immersing the porous separator in a polymer compound soluble in an alkaline electrolyte; and
Winding a plate-like or sheet-like positive electrode and a plate-like or sheet-like negative electrode in a spiral shape through a porous separator carrying a polymer compound soluble in an alkaline electrolyte;
Inserting the wound positive electrode, negative electrode and separator into the battery case, and injecting an alkaline electrolyte;
Sealing the electrolytic cell;
A method for producing a wound alkaline electrolyte secondary battery. A step of producing a porous separator carrying a polymer compound by immersing the porous separator in a polymer compound soluble in an alkaline electrolyte; and
A step of laminating a plurality of plate-like or sheet-like positive electrodes and plate-like or sheet-like negative electrodes via a porous separator carrying a polymer compound soluble in an alkaline electrolyte, and crimping and fixing;
Inserting the fixed positive electrode, negative electrode and separator into the battery case, and injecting an alkaline electrolyte;
Sealing the electrolytic cell;
A method for producing a laminated alkaline electrolyte secondary battery.

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