JP2013069597A - Nonaqueous secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a secondary battery with high safety in which a gas exhaust path is reliably secured.SOLUTION: A nonaqueous secondary battery according to the present invention comprises: an electrode plate group 4 having a positive electrode plate 2 having a positive electrode active material, a negative electrode plate 1 having a negative electrode active material, and a porous insulator 3 arranged between the positive electrode plate and the negative electrode plate; a nonaqueous electrolyte; a cylindrical battery case 7 with a bottom for housing the electrode plate group and the nonaqueous electrolyte; and a sealing plate for closing an opening of the battery case. The battery case has a recess 18 indented inward and downward between the opening and an upper end of the housed electrode plate group, and an insulation plate 19 is arranged between the recess and the electrode plate group. An engagement part 19a engaged with a groove part 20 formed between a battery case inner wall and the recess in the battery case is provided on the insulation plate.

Description

  The present invention relates to a non-aqueous secondary battery.

  With recent advances in electronic technology, small portable electronic devices such as camera-integrated VTRs, mobile phones, digital cameras, and laptop computers have been developed. As portable power sources for use in such devices, they are small, lightweight, and high energy. High density secondary batteries have been developed.

  As such a secondary battery, a nickel cadmium secondary battery, a nickel metal hydride battery, or a non-aqueous electrolyte that uses a light metal such as lithium or sodium that can theoretically generate a high voltage and has a high energy density as a negative electrode active material. A secondary battery can be mentioned. In particular, lithium ion secondary batteries that perform insertion / extraction of lithium ions via non-aqueous electrolytes are compared to nickel / cadmium batteries, nickel / hydrogen batteries, and lead storage batteries that are aqueous electrolyte secondary batteries. Although it has been put into practical use as a device capable of realizing a high output and a high energy density, research and development are being actively promoted in search of a battery having high battery characteristics.

  In the above secondary battery, since the inherent energy is large, it is required to have high safety in the event of an abnormality such as an internal short circuit or an external short circuit. In addition, in these batteries, gas may be generated from the electrolyte for some reason, and if the internal pressure of the battery increases due to the gas, the battery may explode. (For example, Patent Document 1).

  Patent Document 1 discloses a cylindrical container having a neck portion having a reduced diameter at one end, and a spiral electrode group housed in the container and made of a positive electrode, a separator, a negative electrode, and an electrolyte solution. An insulating plate provided between the electrode group and the neck so as to abut against an end surface portion of the electrode group, and disposed outside the insulating plate, and communicates with the electrode group via the insulating plate. A sealing plate having a venting hole, a safety valve placed on the sealing plate so as to seal the venting hole, passing through the insulating plate, and having one end connected to the positive electrode and the other end A cylindrical sealed battery having a lead piece connected to an inner surface of the sealing plate, wherein the insulating plate is equal to or larger than an inner diameter of the neck. . With such a configuration, since the insulating plate is equal to or larger than the inner diameter of the neck of the container, even if an impact force is applied to the battery, the movement of the insulating plate in the container is suppressed, and the spiral electrode It is said that the group is properly restrained in the container, and the spiral electrode group can be prevented from being displaced or deformed in a spiral shape.

JP 2002-100343 A

  In the cylindrical sealed battery disclosed in Patent Document 1, deformation and movement of the electrode group due to impact force can be suppressed by the insulating plate. However, when gas is generated inside the battery, the insulating plate is pushed upward toward the sealing plate by a force whose internal pressure below the insulating plate is larger than the impact force. Since the insulation plate is simply caught on the neck of the container and is prevented from moving upward, the insulation plate can be used when a large internal gas pressure is applied or when the insulation plate is deformed due to high temperatures during abnormal conditions. There is a problem in that the insulation plate comes into contact with the sealing plate due to the catching on the neck. In this case, there is a problem that the insulating plate closes the gas vent hole of the sealing plate, the generated gas cannot escape to the outside of the battery, and the battery internal pressure increases.

  This invention is made | formed in view of this point, The place made into the objective is to provide the highly safe secondary battery by which the gas discharge path | route was ensured reliably.

  The non-aqueous secondary battery of the present invention includes a positive electrode plate having a positive electrode active material, a negative electrode plate having a negative electrode active material, and a porous plate disposed between the positive electrode plate and the negative electrode plate. Group, a nonaqueous electrolyte, a bottomed cylindrical battery case that accommodates the electrode plate group and the nonaqueous electrolyte, and a sealing plate that closes an opening of the battery case, Between the opening and the upper end of the electrode plate group accommodated, there is a recess recessed inward and downward, and an insulating plate is disposed between the recess and the electrode plate group, and the insulation The plate has a configuration in which an engaging portion that engages with a groove formed between the inner wall of the battery case and the recess is provided in the battery case.

  It is preferable that the engaging portion is a convex portion provided at an outer edge portion of the insulating plate. More preferably, the engaging portion is a portion where an outer edge portion of the insulating plate is bent to be convex.

  It is preferable that the engaging portion is provided over the entire circumference of the outer edge portion of the insulating plate.

  The battery case may have a bottomed cylindrical shape.

  The battery case is preferably made of iron.

  Since the engaging portion of the insulating plate is engaged with the portion of the battery case that is recessed below the concave portion, the insulating plate is securely fixed to the concave portion.

It is typical sectional drawing of the battery which concerns on embodiment. It is typical sectional drawing of the battery of a comparative example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following drawings, components having substantially the same function are denoted by the same reference numerals for the sake of brevity.

(Embodiment 1)
<Battery structure>
FIG. 1 is a cross-sectional view schematically showing the configuration of the battery 100 in the first embodiment.

  The battery 100 of the present embodiment is a cylindrical secondary battery as shown in FIG. 1, specifically a lithium ion secondary battery. This lithium ion secondary battery includes a safety mechanism that releases gas to the outside of the battery when the pressure in the battery increases due to an internal short circuit or the like. Hereinafter, a specific configuration of the battery 100 of the present embodiment will be described with reference to FIG.

  As shown in FIG. 1, in the battery 100, an electrode plate group 4 in which a positive electrode (positive electrode plate) 2 and a negative electrode (negative electrode plate) 1 are wound through a separator 3 is present together with a nonaqueous electrolyte solution. The battery case 7 has a bottom cylindrical shape. Since most of the nonaqueous electrolyte is in the electrode group 4, the illustration is omitted. The positive electrode 2 has a configuration in which a positive electrode active material layer is placed on the surface of a sheet-like positive electrode current collector, and the positive electrode active material layer contains a positive electrode active material. The negative electrode 1 has a configuration in which a negative electrode active material layer is placed on the surface of a sheet-like negative electrode current collector, and the negative electrode active material layer contains a negative electrode active material. The separator 3 is made of a porous insulator.

  An upper insulating plate (insulating plate) 19 and a lower insulating plate 10 are respectively arranged above and below the electrode plate group 4, the positive electrode 2 is joined to the filter 12 through the positive electrode lead 5, and the negative electrode 1 is connected to the negative electrode lead 6. It is joined to the bottom of the battery case 7 that also serves as a negative electrode terminal. At this time, the positive electrode lead 5 reaches the filter 12 through the hole 16 provided in the upper insulating plate 19.

  The filter 12 is connected to an inner cap 13, and the protrusion of the inner cap 13 is joined to a metal valve plate 14. Further, the valve plate 14 is connected to a terminal plate 8 that also serves as a positive electrode terminal. The terminal plate 8, the valve plate 14, the inner cap 13, and the filter 12 are integrated to form a sealing plate, and the opening of the battery case 7 is sealed via the gasket 11. In FIG. 1, a positive electrode terminal is arranged on the upper surface side of the cylindrical shape, and a negative electrode terminal is arranged on the lower surface side.

  In the battery 100 of the present embodiment, the electrode plate group 4 is pressed by the upper insulating plate 19 so that the electrode plate group 4 does not move up and down inside the battery case 7, and the concave portion 18 for fixing the upper insulating plate 19 is provided. It is provided on the upper part of the battery case 7. The recess 18 is a portion that is recessed when the battery 100 is viewed from the outside, and is recessed inward and downward of the battery case 7. That is, the recess 18 has a shape that is recessed obliquely downward into the battery case 7 in FIG. 1. Inside the battery 100, the lower portion of the recess 18 is in a state of hanging obliquely downward, and the engaging portion 19 a of the upper insulating plate 19 is engaged with the groove-shaped portion (groove portion 20). The groove portion 20 is an upward groove-shaped portion formed between the inner wall of the battery case 7 and the recess 18 in the battery case 7.

  The recess 18 is provided slightly above the electrode plate group 4 in a state where the electrode plate group 4 is housed in the battery case 7. That is, the recess 18 is provided between the opening of the battery case 7 and the upper end of the electrode plate group 4 accommodated.

  The upper insulating plate 19 is circular, and an engagement portion 19a is provided at the peripheral edge portion. The engaging portion 19 a is a convex portion formed by bending the outer peripheral edge of the upper insulating plate 19 substantially vertically, and is provided on the entire outer periphery of the upper insulating plate 19.

  Next, a case where gas is generated inside the battery 100 will be described.

  When an abnormal situation such as an internal short circuit occurs in the battery 100, gas is generated in the electrode plate group 4. This gas escapes upward from the holes 16 provided in the upper insulating plate 19. Furthermore, it passes through the through hole 12a of the filter 12, and then passes through the through hole 13a of the inner cap 13, thereby pushing the valve body 14 from below. Thus, when the pressure in the battery 100 rises due to the generation of gas, the valve body 14 swells toward the terminal plate 8, and when the pressure exceeds a certain level, the inner cap 13 and the valve body 14 are disconnected. In this way, the current path is interrupted. Further, when the pressure in the battery 100 rises and exceeds a predetermined pressure, the valve body 14 is broken. Thereby, the gas generated in the battery 100 is discharged to the outside through the through hole 12 a of the filter 12, the through hole 13 a of the inner cap 13, the tear of the valve body 14, and the opening 8 a of the terminal plate 8. The

  Here, the battery 101 shown in FIG. 2 is considered for comparison with the battery 100 of the present embodiment. The battery 101 of the comparative example shown in FIG. 2 is different from the battery 100 of the present embodiment in the shape of the recess 17 provided in the battery case 7 and the shape of the upper insulating plate 9, and other configurations and shapes are the same. It is the same as the battery 100 of the embodiment. The concave portion 17 of the battery 101 of the comparative example is recessed substantially perpendicularly to the side wall of the battery case 7. Further, the upper insulating plate 9 of the comparative example does not have an engaging portion, and the outer periphery of the disk shape is only in contact with the concave portion 17.

  When an abnormal situation occurs inside the batteries 100 and 101 and the generation of gas becomes abrupt, gas is once from the hole 16 of the upper insulating plate 19 of the present embodiment or the hole 15 of the upper insulating plate 9 of the comparative example. The upper insulating plates 9 and 19 may be pushed up by the gas without being able to escape. Alternatively, when the gas is locally generated, the gas flow hits the portion of the upper insulating plates 9 and 19 close to the gas generating place, and the portion of the upper insulating plates 9 and 19 is pushed up. Moreover, since heat is also generated inside the batteries 100 and 101 together with the generation of gas, the upper insulating plates 9 and 19 are deformed by the heat and the holes 16 of the upper insulating plate 19 of the present embodiment or the upper insulating plate 9 of the comparative example. The hole 15 may be blocked or may be easily pushed up by gas.

  When the upper insulating plate 9 of the battery 101 of the comparative example is pushed up by gas or deformed by heat as described above, the outer peripheral edge of the upper insulating plate 9 is removed upward from the recess 17, and the upper insulating plate 9 In some cases, the filter itself moves upward to block the through-hole 12a of the filter 12. On the other hand, even if the upper insulating plate 19 of the battery 100 of this embodiment is pushed up by gas or deformed by heat as described above, the engaging portion 19a is firmly engaged with the groove portion 20, so that the upper insulating plate 19 The entire plate 19 does not move in the battery 100, and therefore does not block the through hole 12a.

  When the upper insulating plate 9 closes the through hole 12a of the filter 12 as in the battery 101 of the comparative example, the valve body 14 breaks and the gas is released outside the battery 101 when the through hole 12a is not closed. Even if the battery internal pressure is reached, the gas cannot go out, and the battery internal pressure further increases. Therefore, finally, the high-pressure gas goes out of the battery 101 as compared with the case where the valve body 14 is broken, and safety is lowered. When the battery case 7 is made of iron, if the temperature inside the battery 101 rises due to an abnormal situation, the battery case 7 becomes soft, and high-pressure gas breaks through the side wall of the battery case 7 and comes out. However, in the battery 100 of the present embodiment, since the engaging portion 19a is firmly engaged with the groove portion 20, the upper insulating plate 19 does not block the through hole 12a, and the gas is relatively low in pressure and the terminal plate 8 Since it is discharged from the open portion 8a, safety is high.

  In addition, the safety mechanism for discharging the gas generated in the battery 100 to the outside includes the terminal plate 8, the valve plate 14, the inner cap 13 and the filter 12 shown in FIG. The structure is not limited to the structure in which the valve body 14 is broken, and another structure may be used.

<Battery materials>
As materials for the positive electrode current collector and the negative electrode current collector, those conventionally used as current collectors for lithium ion batteries can be used. Specific examples include foils and sheets made of aluminum, stainless steel, nickel, copper, titanium, or an alloy containing them as a main component. Note that copper or a copper-based alloy is preferably used as the negative electrode current collector, and aluminum or an aluminum-based alloy is preferably used as the positive electrode current collector.

  The positive electrode active material layer is, for example, a positive electrode obtained by mixing an additive such as a positive electrode active material, a conductive material, a binder, and a thickener used as necessary at a predetermined mixing ratio in the presence of a solvent. The mixture paste is applied to the surface of the positive electrode current collector to form a coating film, and the coating film is formed by heating and drying and rolling.

As the positive electrode active material, a material known as a positive electrode active material of a lithium ion secondary battery can be used. Specific examples include lithium-containing transition metal composite oxides such as lithium cobaltate, lithium nickelate, and lithium manganate, olivine-type lithium salts such as LiFePO ₄ , chalcogen compounds such as titanium disulfide and molybdenum disulfide, For example, manganese dioxide. The lithium-containing transition metal composite oxide is a metal composite oxide containing lithium and a transition metal or a metal oxide in which a part of the transition metal in the metal composite oxide is substituted with a different element. Here, examples of the different element include Na, Mg, Sc, Y, Mn, Fe, Co, Ni, Cu, Zn, Al, Cr, Pb, Sb, and B. Mn, Al, Co, Ni, Mg and the like are preferable. One kind or two or more kinds of different elements may be used.

  The mixing ratio of the positive electrode active material is preferably 50 to 99.5% by mass, more preferably 80 to 99% by mass, and particularly preferably 90 to 99% by mass with respect to the entire positive electrode active material layer.

  As the conductive material, a known material used as a conductive material of a lithium ion secondary battery can be used. Specific examples include natural graphite (such as flake graphite), graphite such as artificial graphite, carbon blacks such as acetylene black, ketjen black, channel black, furnace black, lamp black, and thermal black, carbon fiber, and metal fiber. Conductive fibers such as, metal powders such as aluminum, conductive whiskers such as zinc oxide and potassium titanate, conductive metal oxides such as titanium oxide, organic conductive materials such as polyphenylene derivatives, carbon fluoride, etc. Is mentioned. These may be used alone or in combination of two or more.

  The blending ratio of the conductive material is 1 to 50% by mass, further 1 to 30% by mass, particularly 2 to 15% by mass with respect to the amount of the positive electrode active material contained in the entire positive electrode active material layer. A range is preferable.

  As the positive electrode binder, a known material used as a positive electrode binder of a lithium ion secondary battery can be used. Specific examples include fluorine resins such as polyethylene, polypropylene, polyvinyl acetate, polymethyl methacrylate, and polytetrafluoroethylene (PTFE). Examples of the fluororesin include polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and vinylidene fluoride-hexafluoropropylene copolymer. These may be used alone or in combination of two or more.

  The blending ratio of the binder is preferably 1 to 10% by mass, more preferably 1 to 7% by mass, and particularly preferably 1 to 5% by mass with respect to the whole positive electrode active material layer.

  Moreover, as a thickener used as needed, carboxymethylcellulose (CMC), polyethylene oxide, soluble modified acrylonitrile rubbers (“BM-720H (trade name)” manufactured by Nippon Zeon Co., Ltd.) and the like can be mentioned. .

  Specific examples of the solvent include N-methyl-2-pyrrolidone (NMP), tetrahydrofuran, dimethylformamide, ethanol, methanol, butanol, isopropyl alcohol, isobutyl alcohol, deionized water, and the like. These may be used alone or in combination of two or more.

  The positive electrode mixture paste is prepared by mixing the above components and then kneading them by a known kneading method.

  The negative electrode active material layer is, for example, a negative electrode obtained by mixing an additive such as a negative electrode active material, a binder, a conductive material used as necessary, a thickener, and the like at a predetermined mixing ratio in the presence of a solvent. The mixture paste is applied to the surface of the negative electrode current collector to form a coating film, and the coating film is formed by heating and drying and rolling.

  As a negative electrode active material, the well-known material used as a negative electrode active material of a lithium ion secondary battery can be used. Specific examples include graphite materials such as natural graphite (such as flake graphite) and artificial graphite, carbon black such as acetylene black, ketjen black, channel black, furnace black, lamp black, and thermal black, and carbon fiber. Carbon materials; metal lithium, lithium alloys, intermetallic compounds, organic compounds, inorganic compounds, metal complexes, organic polymer compounds, and the like. These may be used alone or in combination of two or more. Among these materials, graphite-based materials, particularly graphite-based materials having an amorphous layer formed on the surface are preferable. In such a graphite-based material having an amorphous layer formed on its surface, lithium is inserted into the crystal not only from the basal plane but also from various directions. Therefore, since the solid-liquid interface reaction is fast, the reaction is governed by diffusion. Therefore, by forming the void v to improve the periphery of the liquid and increase the diffusion rate, the effect is more remarkably exhibited.

  The mixing ratio of the negative electrode active material is preferably 50 to 99.5% by mass, more preferably 80 to 99% by mass, and particularly preferably 90 to 99% by mass with respect to the entire negative electrode active material layer. .

  As a specific example of the negative electrode binder, a known material used as a negative electrode binder of a lithium ion secondary battery can be used. Specific examples include polyethylene, polypropylene, polytetrafluoroethylene, polyvinylidene fluoride, and modified styrene-butadiene rubber.

  The blending ratio of the negative electrode binder is preferably 1 to 10% by mass, more preferably 1 to 7% by mass, and particularly preferably 1 to 5% by mass with respect to the entire negative electrode active material layer. .

  As the conductive material used as necessary, the same conductive material as that used in the positive electrode can be used without particular limitation. The blending ratio of the conductive material is 0 to 25% by mass, more preferably 0 to 10% by mass, and particularly 0 to 5% by mass with respect to the amount of the negative electrode active material contained in the entire negative electrode active material layer. A range is preferable.

  Similarly to the positive electrode mixture paste, the negative electrode mixture paste is prepared by mixing the above-mentioned components and then kneading by a known kneading method.

  As the battery case 7, for example, an aluminum case, an iron case whose inner surface is nickel-plated, or the like can be used. However, an iron case is preferable in view of strength and cost. In this embodiment, an iron case is used. It is said. In the present embodiment, the battery case 7 has a bottomed cylindrical shape, but the shape of the battery case may be any cylindrical shape such as a cylindrical shape or a prismatic shape. For the cross section of the electrode plate group, a shape such as a circle or an ellipse is selected according to the shape of the battery case.

  As the non-aqueous electrolyte solution, a non-aqueous solvent in which a lithium salt is dissolved is preferably used. Specific examples of the non-aqueous solvent include cyclic carbonates such as ethylene carbonate (EC), propylene carbonate (PC) and butylene carbonate (BC); dimethyl carbonate (DMC) and diethyl carbonate (DEC). Chain carbonates such as ethyl methyl carbonate (EMC) and dipropyl carbonate (DPC); aliphatic carboxylic acid esters such as methyl formate, methyl acetate, methyl propionate and ethyl propionate, γ-butyrolactone, γ-valero Lactones such as lactones; chain ethers such as 1,2-dimethoxyethane (DME), 1,2-diethoxyethane (DEE) and ethoxymethoxyethane (EME); cyclic ethers such as tetrahydrofuran and 2-methyltetrahydrofuran Dimethyl sulfoxide, 1, 3-dioxolane, formamide, acetamide, dimethylformamide, dioxolane, acetonitrile, propylnitrile, nitromethane, ethyl monoglyme, phosphate triester, trimethoxymethane, dioxolane derivative, sulfolane, methylsulfolane, 1,3-dimethyl-2-imidazo Examples include ridinone, 3-methyl-2-oxazolidinone, propylene carbonate derivatives, tetrahydrofuran derivatives, ethyl ether, 1,3-propane sultone, anisole, dimethyl sulfoxide, N-methyl-2-pyrrolidone and the like. These may be used alone or in combination of two or more.

Specific examples of the lithium salt dissolved in the non-aqueous solvent include LiClO ₄ , LiBF ₄ , LiPF ₆ , LiAlCl ₄ , LiSbF ₆ , LiSCN, LiCl, LiCF ₃ SO ₃ , LiCF ₃ CO ₂ , Li (CF ₃ SO ₂ ). ₂ , LiAsF ₆ , LiN (CF ₃ SO ₂ ) ₂ , LiB ₁₀ Cl ₁₀ , lower aliphatic lithium carboxylate, LiCl, LiBr, LiI, chloroborane lithium, lithium tetraphenylborate, lithium imide salt and the like. These may be used alone or in combination of two or more. The amount of lithium salt dissolved in the non-aqueous solvent is not particularly limited, but is preferably 0.2 to 2 mol / L, and more preferably 0.5 to 1.5 mol / L.

  Various additives may be further added to the non-aqueous electrolyte solution for the purpose of improving the charge / discharge characteristics of the battery. Specific examples of such additives include vinylene carbonate, vinyl ethylene carbonate, phosphazene and fluorobenzene, triethyl phosphite, triethanolamine, cyclic ether, ethylenediamine, n-glyme, pyridine, hexaphosphate triamide, nitrobenzene derivatives, crown Examples include ethers, quaternary ammonium salts, and ethylene glycol dialkyl ethers. These additives are preferably blended in an amount of about 0.5 to 10% by mass of the non-aqueous electrolyte.

  As the separator, a known insulating microporous sheet used in lithium ion secondary batteries can be used. The microporous thin film preferably has a function of closing the pores at a certain temperature or higher and increasing the resistance. As the material of the microporous thin film, polyolefin such as polypropylene and polyethylene having excellent organic solvent resistance and hydrophobicity is preferably used. In addition, a sheet made of glass fiber, a nonwoven fabric, a woven fabric, or the like can be used.

(Other embodiments)
The above-described embodiment is an exemplification of the present invention, and the present invention is not limited to these examples, and these examples may be combined or partially replaced with known techniques, common techniques, and known techniques. Also, modified inventions easily conceived by those skilled in the art are included in the present invention. For example, the configuration of the positive electrode plate and the negative electrode plate may be other than the above configuration, and the positive electrode active material and the negative electrode active material may be any active material. Further, the battery may be a nickel cadmium secondary battery other than a lithium ion secondary battery, a nickel hydrogen battery, or the like.

  The engaging portion of the upper insulating plate does not need to be provided on the entire outer periphery. If the engagement portions are provided at three positions every 120 degrees, the function of the present application is exhibited. However, if the engagement portions are provided over the entire circumference, the upper insulating plate is more reliably disposed in the recess. It is preferable because it can be fixed. Further, the engaging portion may be formed by bending, or may be formed from the beginning by injection molding or the like. Or you may adhere | attach a ring-shaped member and form an engaging part.

  Further, in the process of manufacturing the battery, the upper insulating plate having a diameter larger than the inner diameter of the battery case is placed on the electrode plate group in the battery case, and then the upper part of the battery case is pressed from the outside to form the concave portion. The engaging portion may be formed by bending the outer periphery of the upper insulating plate simultaneously with the formation.

  The concave portion may be formed over the entire circumference of the battery case or may be formed in a part of the circumference.

  The upper insulating plate may be formed of an insulating plastic, but may be formed of other insulating materials such as an inorganic material such as ceramic.

  As described above, the non-aqueous secondary battery according to the present invention is useful as a lithium-ion secondary battery for various power sources and the like because it can secure a gas discharge path at the time of abnormality.

1 Negative electrode (negative electrode plate)
2 Positive electrode (positive electrode plate)
3 Separator (porous insulator)
4 electrode plate group 7 battery case 8 terminal plate 9, 19 upper insulating plate (insulating plate)
12 Filter 13 Inner cap 14 Valve element 17 Recess 18 Recess 19a Engaging portion 20 Groove 100, 101 Battery

Claims (6)

A positive electrode plate having a positive electrode active material, a negative electrode plate having a negative electrode active material, and an electrode plate group having a porous insulator disposed between the positive electrode plate and the negative electrode plate;
A non-aqueous electrolyte,
A bottomed cylindrical battery case containing the electrode plate group and the non-aqueous electrolyte;
A sealing plate for closing the opening of the battery case,
The battery case has a recess recessed inwardly and downwardly between the opening and the upper end of the electrode group accommodated.
An insulating plate is disposed between the recess and the electrode plate group,
The non-aqueous secondary battery, wherein the insulating plate is provided with an engaging portion that engages with a groove formed between the inner wall of the battery case and the recess in the battery case.   The non-aqueous secondary battery according to claim 1, wherein the engaging portion is a convex portion provided on an outer edge portion of the insulating plate.   The non-aqueous secondary battery according to claim 2, wherein the engaging portion is a portion in which an outer edge portion of the insulating plate is bent to be a convex shape.   The non-aqueous secondary battery according to claim 2 or 3, wherein the engaging portion is provided over the entire circumference of the outer edge portion of the insulating plate.   The non-aqueous secondary battery according to claim 1, wherein the battery case has a bottomed cylindrical shape.   The non-aqueous secondary battery according to claim 1, wherein the battery case is made of iron.

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