JP2013037796A - Nonaqueous electrolyte coin-shaped battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte coin-shaped battery which can ensure a high capacity while exhibiting excellent long-term storage characteristics by using low-price exterior parts.SOLUTION: A clad material produced by cladding a nickel plate at least to the outer surface of a steel base is applied as the constituent raw material of a sealing plate. When compared with a conventional nonaqueous electrolyte coin-shaped battery having a stainless steel sealing plate, manufacturing cost can be reduced, and rusting on the outer surface or leakage of electrolyte is minimized. A high capacity nonaqueous electrolyte coin-shaped battery similar to that using a stainless steel sealing plate is provided.

Description

  The present invention relates to a non-aqueous electrolyte coin-type battery having excellent long-term storage characteristics.

  In a non-aqueous electrolyte coin-type battery represented by a manganese dioxide lithium battery, a graphite fluoride lithium battery, or the like, a stainless steel plate is generally used as a base material for a sealing plate or a positive electrode case. The stainless steel plate has high strength, and even if the sealing plate and the positive electrode case are thinned to some extent, the strength can be secured, and problems such as leakage and battery deformation are unlikely to occur.

  However, since the price of the stainless steel plate is high, there is a problem that the manufacturing cost of the battery increases. In response to this problem, there is a possibility that the manufacturing cost can be reduced by replacing the Ni-plated steel sheet, which is cheaper than the stainless steel sheet. However, when using Ni-plated steel sheets, there was a problem in long-term storage characteristics such as generation of rust on the surface of exterior parts and low sealing performance due to low strength compared to stainless steel. .

  In response to this problem, at least the outer surface of the steel substrate is Ni-plated in a sealing plate having an upper surface wall that serves as a negative electrode exterior component of a nonaqueous electrolyte coin-type battery and a curved portion curved downward from the upper surface wall. And a Ni-plated steel plate in which a region where Fe and Ni are diffused between each other exists between the Ni-plated portion and the steel substrate portion, and the curvature radius R (mm) of the curved portion of the sealing plate ) And the internal angle θ (°) of the curved portion is set to 0.0060 to 0.0160, whereby an invention for solving the above-described problem of the Ni-plated steel sheet has been proposed (Patent Document 1). reference).

JP 2007-207534 A

  However, when a Ni-plated steel sheet as disclosed in Patent Document 1 is used for a sealing plate of a non-aqueous electrolyte coin-type battery, leakage occurs when stored for a long period of time, or the curved portion of the sealing plate has an appearance due to rust. There was something that caused defects. In Patent Document 1, heat treatment is performed to form a region in which Fe and Ni are diffused between the Ni-plated portion and the steel base portion of the Ni-plated steel sheet, and thus the iron itself is annealed. The hardness decreases at the same time, the difference in hardness compared to conventional stainless steel becomes larger, the strength of the caulking seal must be reduced, and leakage occurs from a place with poor sealing properties when stored for a long period of time. . In addition, since the Ni plating layer aggregates due to heat treatment, the particle size becomes large, so that rust is generated by partially exposing the steel surface due to deformation during caulking sealing.

  Moreover, in patent document 1, it is a sealing board which has a curved part curved downward from the upper surface wall and the upper surface wall, and the curvature radius R (mm) of the said curved part and the internal angle (theta) (degree) of the curved part The ratio R / θ needs to keep a value of 0.0060 to 0.0160. For this reason, the volumetric efficiency is deteriorated due to the shape restriction, and the battery cannot be increased in capacity.

  The present invention has been made in view of the above circumstances, and its purpose is to have a sealing plate made of a steel base material, and to prevent the occurrence of rust and leakage on the outer surface during long-term storage. The object is to provide a non-aqueous electrolyte coin-type battery that can be suppressed and additionally have a high capacity.

  In order to achieve the above object, a non-aqueous electrolyte coin-type battery of the present invention includes a positive electrode case and a sealing plate made of a metal material together with a non-aqueous electrolyte and a power generation element in which a positive electrode and a negative electrode are arranged to face each other via a separator. In the non-aqueous electrolyte coin-type battery encapsulated in an exterior part of a gasket made of resin, a clad material in which a nickel plate is clad on at least the outer surface of a steel substrate is used as the sealing plate. Is.

  According to the present invention, by applying a specific Ni-plated steel plate to the constituent material of the sealing plate, the cost during manufacturing can be reduced as compared with a nonaqueous electrolyte coin-type battery having a conventional stainless steel sealing plate. In addition, it is possible to provide a non-aqueous electrolyte coin-type battery that has the same high capacity as the case where a stainless steel sealing plate is used in addition to suppressing the occurrence of rust and liquid leakage on the outer surface.

Sectional drawing of the nonaqueous electrolyte coin-type battery in one embodiment of this invention The enlarged view which shows the principal part of the sealing board of the nonaqueous electrolyte coin-type battery in one embodiment of this invention

  According to a first aspect of the present invention, a power generation element in which a positive electrode and a negative electrode are arranged opposite to each other with a separator interposed between a battery case made of a metal material and a sealing plate, and a gasket made of a resin, together with a non-aqueous electrolyte. In the non-aqueous electrolyte coin-type battery, a clad material in which a nickel plate is clad on at least the outer surface of a steel substrate is used as the sealing plate. Here, the outer surface means a surface located outside the battery when the battery is manufactured. This configuration reduces production costs and increases productivity, and further suppresses the occurrence of rust and leakage on the outer surface. In addition, the same high level as when using a stainless steel sealing plate is used. A non-aqueous electrolyte coin-type battery having a capacity can be obtained.

  By clad a nickel plate on at least the outer surface of the steel substrate, even if the sealing plate is processed into various shapes, the steel substrate itself is not exposed to the outside, and high temperature and high humidity environment is likely to generate rust. It is stable even underneath, and no rust is seen. In addition, since there is no generation of rust, there is no need to limit the shape of the sealing plate, it can be processed into the same shape as stainless steel, and the liquid leakage performance by sealing is equivalent to that of stainless steel. Further, the discharge capacity of the battery is not reduced, and the capacity can be increased. In addition, the cost of the material part of the parts can be reduced.

  According to a second aspect of the present invention, the clad has a Vickers hardness of 160 to 240 HV. Depending on the Vickers hardness of the clad material used, the battery performance is greatly affected. The nonaqueous electrolyte coin-type battery is sealed by crimping to deform the positive electrode case and compress the gasket of the packing material. All the load applied when deforming the positive electrode case is applied to the sealing plate. When the strength of the sealing plate is not sufficient, the sealing plate is deformed, and the shape of the battery becomes strange or the liquid leaks. On the contrary, if the caulking load is reduced to suppress the deformation of the sealing plate, the positive electrode case is not sufficiently deformed, the gasket is not sufficiently compressed, the sealing performance is lowered, and the liquid leaks. . If it exceeds 240 HV, it is difficult to process the part, and in some cases, there is a risk that the part may crack, which is not preferable.

According to a third aspect of the present invention, the thickness of the clad material is 0.15 to 0.25 mm. If the thickness is less than 0.15 mm, the strength of the clad material itself is reduced, so that the weighted pressure resistance of the caulking seal is also lowered, and the leakage resistance performance is lowered. Even if the thickness is greater than 0.25 mm, the strength is not significantly improved, which is not preferable from the viewpoint of battery capacity.

  According to a fourth aspect of the present invention, the thickness of the nickel layer of the clad material is 2 to 5 μm. In conventional plating, the thickness must be increased due to the risk of pinholes and the like. However, the thickness can be reduced to about 1 μm by using a clad. However, from the viewpoint of stability against external scratches, the thickness is preferably greater than 2 μm. Even if it becomes thicker than 5 μm, there is no difference in characteristics and the price increases.

  FIG. 1 shows an example of the non-aqueous electrolyte coin-type battery of the present invention. As shown in FIG. 1, in a non-aqueous electrolyte coin-type battery, a negative electrode 4 and a positive electrode 6 are arranged opposite to each other with a separator 5 inside an exterior formed by a sealing plate 2, a positive electrode case 1 and a gasket 3. The power generation element is enclosed together with a non-aqueous electrolyte (not shown).

  The sealing plate 2 is a clad material obtained by clad a nickel plate on at least the outer surface of a steel substrate. In the case of a clad material in which a nickel plate is clad on both surfaces of a steel base, it is preferable because management for preventing the occurrence of rust on the steel base during storage of parts becomes easy.

  The Vickers hardness of the clad material is preferably 160 to 240 HV.

  The thickness of the clad material is preferably 0.15 to 0.25 mm.

  The thickness of the nickel layer of the clad material is preferably 2 to 5 μm.

  FIG. 2 is an enlarged view showing a main part of the sealing plate 2 shown in FIG. Here, the sealing plate 2 is a clad material having nickel layers 8 on both surfaces of the steel substrate 7. The sealing plate 2 has a curved portion 2b extending from the upper surface wall 2a. The curved portion 2b of the sealing plate 2 means a portion having a constant curvature, starting from a curved portion directed downward from the substantially flat top wall 2a and ending with a curved portion where the curvature changes. . The curvature radius R of the curved portion 2b is a curved radius of curvature of the outer surface (battery outer surface) of the curved portion 2b of the sealing plate 2 as shown in FIG. 2, and the inner angle θ of the curved portion 2b is It is the inner angle between the two line segments when a line segment toward the center of curvature is drawn from both ends of the outer surface of the curved portion 2b.

  The positive electrode case 1 is formed by forming a nickel-plated stainless steel plate into a bottomed cylindrical shape by drawing.

  The positive electrode 6 according to the non-aqueous electrolyte coin-type battery of the present invention is obtained by pressure-molding a positive electrode mixture containing a positive electrode active material, a conductive additive and a binder into a pellet shape. The positive electrode active material is not particularly limited, but is an oxide of manganese, cobalt, nickel, magnesium, copper, iron, niobium, or a composite oxide thereof, manganese, cobalt, nickel, magnesium, copper, iron, niobium and lithium. A composite oxide, graphite fluoride, or the like can be used.

  As the conductive assistant, carbon black such as acetylene black and ketjen black, graphite such as artificial graphite, and the like can be used. A conductive material can be used individually by 1 type or in combination of 2 or more types.

Examples of the binder include polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), modified PVDF, tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer. Polymer (PFA), vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-chlorotrifluoroethylene copolymer, ethylene-tetrafluoroethylene copolymer (ETFE resin), vinylidene fluoride-pentafluoropropylene copolymer Polymer, propylene-tetrafluoroethylene copolymer, ethylene-chlorotrifluoroethylene copolymer (ECTFE), vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer, etc. Fluorocarbon resin, styrene-butadiene rubber (SBR), modified acrylonitrile rubber, ethylene - like acrylic acid copolymer. A binder can be used individually by 1 type or in combination of 2 or more types.

  As the negative electrode 4 according to the present invention, lithium or a lithium alloy can be used. Examples of the lithium alloy include Li—Al, Li—Sn, Li—Si, and Li—Pb. Further, as the negative electrode active material, carbon-based materials such as natural graphite, artificial graphite, and non-graphitizable carbon, and oxides such as silicon monoxide, lithium titanate, niobium pentoxide, and molybdenum dioxide can be used. It is used as a negative electrode as a mixture comprising a conductive additive and a binder for a carbon-based material or an oxide negative electrode active material.

  As the conductive auxiliary agent and binder, those exemplified for the positive electrode can be used.

Non-aqueous electrolytes include cyclic carbonates such as propylene carbonate, ethylene carbonate, butylene carbonate and vinylene carbonate, chain carbonates such as dimethyl carbonate, diethyl carbonate and methyl ethyl carbonate, 1,2-dimethoxyethane, diglyme ( 1 type of solvent selected from ethers such as diethylene glycol methyl ether), triglyme (triethylene glycol dimethyl ether), tetraglyme (tetraethylene glycol dimethyl ether), 1,2-dimethoxyethane, 1,2-diethoxymethane, tetrahydrofuran, or 2 An organic electrolytic solution prepared by dissolving an electrolyte in a mixed solvent of seeds or more to a concentration of about 0.3 to 2.0 mol / L is used. Examples of the electrolyte include LiBF ₄ , LiPF ₆ , LiAsF ₆ , LiSbF ₆ , LiClO ₄ , LiCF ₃ SO ₃ , LiC ₄ F ₉ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ , LiN (C ₂ F ₅ SO ₂ ) ₂ etc. are used.

  The separator 5 is not particularly limited as long as the positive electrode 6 and the negative electrode 4 can be prevented from being short-circuited. Further, it is desirable that the separator 5 is excellent in electrolyte permeability and does not become an ion migration resistance. Typical materials include polyolefin, polyester, polycarbonate, polyacrylate, polymethacrylate, polyamide, polytetrafluoroethylene, polyvinylidene fluoride, polysulfone, polyethersulfone, polybenzimidazole, polyetheretherketone, polyphenylene, etc. Examples of the shape include a nonwoven fabric and a microporous film.

  As a material of the gasket 3, for example, PP, PPS, PEEK, or the like can be used.

  Hereinafter, preferred embodiments of the present invention will be described.

Example 1
FIG. 1 is a cross-sectional view of a non-aqueous electrolyte coin cell battery having a thickness of 3.2 mm and a diameter of 20 mm used in an example of the present invention.

  For the positive electrode case 1, a stainless steel plate having a thickness of 3 mm and plated with a nickel plate having a thickness of 0.2 μm formed into a bottomed cylindrical shape having a peripheral wall height of 3 mm by drawing.

  For the sealing plate 2, a clad material in which a nickel plate was clad on both surfaces of a steel base material was used. The thickness of the nickel layer on both outer surfaces of the clad material was 3 μm, the thickness of the steel in the interior was 0.25 mm, and the Vickers hardness was 200 HV. The sealing plate 2 is formed by drawing the clad material into a bottomed cylindrical shape having a curved portion 2b as shown in FIG.

  Further, as the shape of the curved portion 2b of the sealing plate 2, the radius of curvature R was 0.4 mm, and the internal angle θ of the curved portion 2b was 90 °. At this time, R / θ was 0.0044.

  The positive electrode 6 is composed of a mixture using manganese dioxide as a positive electrode active material, carbon black as a conductive additive, and polytetrafluoroethylene as a binder. These were mixed so that manganese dioxide was 90% by mass, artificial graphite was 5% by mass, and polytetrafluoroethylene was 5% by mass to prepare a positive electrode mixture. This positive electrode mixture was subjected to pressure molding to produce a positive electrode 6. The positive electrode 6 had a diameter of 16 mm and a thickness of 1.9 mm.

As the non-aqueous electrolyte, an electrolyte prepared by dissolving 0.5 mol / l of LiClO _{4 in} a mixed solvent of propylene carbonate and 1,2-dimethoxyethane in a volume ratio of 1: 1 was used.

  As the negative electrode 4, a lithium plate having a thickness of 0.58 mm punched out into a circle having a diameter of 16 mm was used, and the negative electrode 4 was accommodated in the sealing plate 2.

  A polypropylene nonwoven fabric is used as the separator 5 and a polypropylene gasket is used as the annular gasket 3.

  A power generation element composed of the positive electrode 6, the negative electrode 4, the separator 5, the nonaqueous electrolyte, and the like is accommodated in a space formed by the positive electrode case 1, the sealing plate 2, and the gasket 3, and the open end of the positive electrode case 1 is inward The annular gasket 3 is pressed against the peripheral folded portion of the sealing plate 2 and the inner peripheral surface of the opening end portion of the positive electrode case 1 by so-called caulking, thereby sealing the opening portion of the positive electrode case 1 to the inside of the battery. Is sealed.

  The non-aqueous electrolyte secondary battery thus obtained was designated as an inventive battery 1 according to Example 1.

  An inventive battery 2 having the same configuration as the inventive battery 1 was produced except that the shape of the sealing plate 2 of the inventive battery 1 was such that the radius of curvature R was 0.55 mm and the internal angle θ of the curved portion 2b was 85 °.

  An inventive battery 3 having the same configuration as the inventive battery 1 was prepared except that the sealing plate 2 of the inventive battery 1 had a radius of curvature R of 0.52 mm and an internal angle θ of the curved portion 2b of 90 °.

  An inventive battery 4 having the same configuration as the inventive battery 1 was prepared except that the sealing plate 2 of the inventive battery 1 had a curvature radius R of 0.45 mm and an internal angle θ of the curved portion 2b of 85 °.

  Inventive battery 5 having the same configuration as that of inventive battery 1 was prepared except that the shape of the sealing plate 2 of the inventive battery 1 was such that the radius of curvature R was 0.35 mm and the internal angle θ of the curved portion 2b was 90 °.

  An inventive battery 6 having the same configuration as the inventive battery 1 was produced except that the sealing plate 2 of the inventive battery 1 had a curvature radius R of 0.6 mm and an internal angle θ of the curved portion 2b of 80 °.

Instead of the clad material which is the base material of the sealing plate 2 of the inventive battery 1, a steel base material having a matte Ni plating on both surfaces was used. The thickness of the matte Ni plating layer and the thickness of the steel substrate are respectively
3 μm and 0.25 mm. This Ni-plated steel plate is heat-treated at 780 ° C. for 60 seconds using a continuous annealing method to form an Fe—Ni diffusion region between the plating layer and the steel substrate. Vickers hardness is 120HV. The non-aqueous electrolyte coin-type battery thus obtained was designated as comparative battery A.

  Instead of the clad material which is the base material of the sealing plate 2 of the inventive battery 1, a steel base material having a matte Ni plating on both surfaces was used. The thickness of the matte Ni plating layer and the thickness of the steel substrate are 3 μm and 0.25 mm, respectively. This Ni-plated steel plate is heat-treated at 780 ° C. for 60 seconds using a continuous annealing method to form an Fe—Ni diffusion region between the plating layer and the steel substrate. A Vickers hardness of 120 HV was used. Further, as the shape of the curved portion 2b of the sealing plate 2, the radius of curvature R was 0.6 mm, and the internal angle θ of the curved portion 2b was 78 °. At this time, R / θ was 0.0077. The non-aqueous electrolyte coin-type battery thus obtained was designated as comparative battery B.

  The above-described inventive batteries 1 to 5 and comparative batteries A and B were subjected to an initial discharge capacity, a high temperature and high humidity test, and a thermal shock test. The number of tests for each battery was 25.

  In the initial discharge capacity measurement, a constant current discharge of 0.2 mA was performed at 20 ° C., and the discharge voltage was up to a final voltage of 2.0 V. Table 1 shows the results of calculating the average value of 25 capacities and then calculating the value with the capacity value of Invention Battery A being 100.

  The high temperature and humidity test was stored for 15 days in an atmosphere of 85 ° C. and 90% relative humidity, and the presence or absence of liquid leakage and the presence or absence of corrosion of the curved portion 2b of the sealing plate were examined. In addition, the discharge capacity after storage was measured by the same method as the initial capacity measurement. The results are shown in (Table 1).

  In the thermal shock test, after holding for 30 minutes at -40 ° C, the temperature is instantaneously changed from -40 ° C to 85 ° C, and the thermal shock that is held for 30 minutes at 85 ° C is one cycle. The presence or absence was confirmed. The results are shown in (Table 1).

  As shown in (Table 1), invention batteries 1 to 6 using a clad material in which a nickel plate is clad on both sides of a steel base material as a sealing plate 2 show a large discharge capacity even after a high-temperature and high-humidity environment test, No leakage or corrosion was observed, and the performance was excellent. Also, excellent liquid leakage performance was obtained in the thermal shock test. By using the clad material, the strength of the sealing plate is increased, and a sufficient caulking pressure resistance can be secured, and an excellent sealing performance can be realized.

In comparative batteries A and B, when a Ni-plated steel sheet having an Fe—Ni diffusion region was used as the base material of the sealing plate, the discharge capacity after the high-temperature and high-humidity environment test was significantly deteriorated. In the thermal shock test, a lot of leaking batteries were generated. In particular, in the comparative battery A having a sealing plate shape designed to increase R by decreasing R and increasing θ, rust and liquid leakage were observed after the high temperature and high humidity environment test. When Ni-plated steel sheet with Fe-Ni diffusion region is used, the strength of the sealing plate is insufficient and the regulation of the part shape and the caulking seal cannot be strengthened. became.

(Example 2)
Inventive battery 7 having the same configuration as inventive battery 1 was prepared except that a clad material having a Vickers hardness of 140 HV was used instead of the clad material used in inventive battery 1.

  Inventive battery 8 having the same configuration as inventive battery 1 was produced except that a clad material having a Vickers hardness of 160 HV was used instead of the clad material used in inventive battery 1.

  Inventive battery 9 having the same structure as inventive battery 1 was produced except that a clad material having a Vickers hardness of 180 HV was used instead of the clad material used in inventive battery 1.

  Inventive battery 10 having the same configuration as inventive battery 1 was produced except that a clad material having a Vickers hardness of 220 HV was used instead of the clad material used in inventive battery 1.

  Inventive battery 11 having the same configuration as inventive battery 1 was prepared except that a clad material having a Vickers hardness of 240 HV was used instead of the clad material used in inventive battery 1.

  Inventive battery 12 having the same configuration as inventive battery 1 was produced except that a clad material having a Vickers hardness of 260 HV was used in place of the clad material used in inventive battery 1.

  Table 2 shows the results of evaluations similar to those in Example 1 for the inventive batteries 7 to 12.

  Inventive batteries 1 and 7 to 12 exhibited excellent liquid leakage performance in high temperature and high humidity storage and thermal shock tests. Inventive battery 7 having a low Vickers strength of the clad material, a slight decrease in capacity was observed in the discharge after the high temperature and high humidity environment test. Since the confidentiality of the sealing part was slightly lowered and the amount of moisture entering the battery was increased, the capacity was reduced due to the consumption of lithium as the negative electrode active material.

  Further, in the inventive battery 12 having a high Vickers strength of the clad material, only one minute rust was observed in the R portion of the sealing plate after high temperature and high humidity storage. It is considered that stress was applied during the processing of the parts, scratches were generated in the R portion of the sealing plate, and the underlying steel substrate portion was exposed.

(Example 3)
Instead of the clad material used in the invention battery 1, the thickness of the steel substrate in the interior is 0.10 mm.
An inventive battery 13 having the same configuration as that of the inventive battery 1 was prepared except that the thickness of the positive electrode and the negative electrode was changed correspondingly.

  Instead of the clad material used in the inventive battery 1, a clad material having an inner steel substrate thickness of 0.15 mm was used, and the thicknesses of the positive electrode and the negative electrode were changed accordingly. An inventive battery 14 having the same configuration was produced.

  Instead of the clad material used in the inventive battery 1, a clad material having an inner steel base thickness of 0.25 mm was used, and the thickness of the positive electrode / negative electrode was changed accordingly. Inventive battery 15 having the same configuration was produced.

  Instead of the clad material used in the inventive battery 1, a clad material having an inner steel base thickness of 0.30 mm was used, and the thicknesses of the positive electrode and the negative electrode were changed accordingly. Inventive battery 16 having the same configuration was produced.

  The results of performing the same evaluation as in Example 1 for the inventive batteries 13 to 16 are shown in (Table 3).

  Inventive batteries 1 and 13 to 16 showed no occurrence of leakage or corrosion in high-temperature and high-humidity storage and thermal shock tests.

  As for the inventive batteries 13 and 14, the initial discharge capacity was increased by reducing the thickness of the steel substrate. On the other hand, the initial discharge capacities of the inventive batteries 15 and 16 having a thick steel substrate were small. However, the capacity deterioration of the inventive battery 13 was accelerated after storage. Deterioration progressed because the steel substrate thickness was reduced, the strength of the sealing plate was lowered, and the confidentiality of the sealed portion was lowered. The thicker the steel substrate, the smaller the difference in discharge capacity before and after the high temperature and humidity, and the sealing plate was improved in strength by improving the strength of the sealing plate.

(Example 5)
Inventive battery 17 having the same configuration as that of inventive battery 1 was prepared except that a clad material having a nickel layer thickness of 1 μm was used instead of the clad material used in inventive battery 1.

  Inventive battery 18 having the same configuration as that of inventive battery 1 was prepared except that a clad material having a nickel layer thickness of 2 μm was used instead of the clad material used in inventive battery 1.

  Inventive battery 19 having the same configuration as that of inventive battery 1 was produced except that a clad material having a nickel layer thickness of 4 μm was used instead of the clad material used in inventive battery 1.

  Inventive battery 20 having the same configuration as inventive battery 1 was prepared except that a clad material having a nickel layer thickness of 5 μm was used instead of the clad material used in inventive battery 1.

  Inventive battery 21 having the same configuration as that of inventive battery 1 was prepared except that a clad material having a nickel layer thickness of 6 μm was used instead of the clad material used in inventive battery 1.

  Table 4 shows the results of the same evaluations as in Example 1 for the inventive batteries 17 to 21.

  In invention battery 17, the discharge capacity after storage was reduced. It is considered that the discharge capacity was affected because the value of the contact resistance was increased by reducing the thickness of the nickel plating. No difference in performance was found for inventive batteries 20 to 21 having a thick nickel plating.

  In addition, about said Example, although described about the case where the clad material which provided the nickel layer on both surfaces of the steel base material was used, it is the same also when the clad material which provided the nickel layer only on the outer surface is used. The effect was obtained.

  As described above, the present invention can be applied to various applications by providing a non-aqueous electrolyte coin-type battery that uses low-cost exterior parts, has excellent long-term storage characteristics, and can be increased in capacity. Yes, the industrial utility value is very high.

DESCRIPTION OF SYMBOLS 1 Positive electrode case 2 Sealing plate 2a Upper surface wall 2b Curved part 3 Gasket 4 Negative electrode 5 Separator 6 Positive electrode 7 Steel base material 8 Nickel layer

Claims (4)

A non-aqueous electrolyte coin-type battery in which a power generation element in which a positive electrode and a negative electrode are opposed to each other with a separator interposed between a non-aqueous electrolyte, a positive electrode case made of a metal material, a sealing plate, and a gasket made of a resin A non-aqueous electrolyte coin-type battery characterized in that a clad material in which a nickel plate is clad on at least the outer surface of a steel substrate is used as the sealing plate. The non-aqueous electrolyte coin-type battery according to claim 1, wherein the clad material has a Vickers hardness of 160 to 240 HV. The non-aqueous electrolyte coin-type battery according to claim 1, wherein the clad material has a thickness of 0.15 to 0.25 mm. The thickness of the nickel layer of the said clad material is 2-5 micrometers, The nonaqueous electrolyte coin type | mold battery in any one of Claims 1-3 characterized by the above-mentioned.