JP5083931B2 - Battery container manufacturing method, battery container manufactured by the battery container manufacturing method, and battery using the battery container - Google Patents

Description

  The present invention relates to a battery container manufacturing method, a battery container manufactured by the battery container manufacturing method, and a battery using the battery container. In particular, the present invention relates to an inexpensive battery container used for an alkaline manganese battery, a lithium primary battery, a nickel cadmium battery, a nickel metal hydride battery, or a lithium ion battery, or a battery using the container.

  In recent years, portable devices such as audio devices and mobile phones have been used in various fields, and alkaline batteries that are primary batteries, nickel-hydrogen batteries that are secondary batteries, lithium ion batteries, and the like are frequently used as operating power sources. In these batteries, there is a constant demand for higher performance such as higher output and longer life, and battery containers filled with positive and negative electrode active materials are also required to have improved performance as important components of the battery. ing. For example, in a battery using a can formed by press drawing and ironing, in order to reduce the internal resistance of the battery, a hard nickel-cobalt alloy plating is coated on the side that becomes the inner surface of the can, and silver plating or the like is coated thereon. For example, a method of covering the surface (see Patent Document 1, for example) has been proposed.

  However, although the method described in Patent Document 1 is excellent in battery performance, it is an expensive battery container because of expensive silver plating. Further, when a steel plate is formed into a battery container and nickel-based plating is applied, the inner surface of the battery container is plated only thinly. In particular, the bottom of the inner surface of the battery container is very thin, which causes poor battery performance.

Prior art document information relating to the present application includes the following.
JP 09-306439 A

  In the present invention, a thin nickel or nickel alloy plating is applied, or a thin nickel or nickel alloy plating is applied, followed by a thermal diffusion treatment, a deep drawing method, a drawing ironing method (DI processing method), a drawing stretch processing method. (DTR processing method) Or, after forming into a battery container using a processing method that uses both ironing and stretching after drawing, nickel plating is further applied to the outer surface of the battery container or a part of the outer surface where corrosion resistance is required The object is to provide a battery container manufacturing method that is inexpensive and excellent in battery performance and corrosion resistance, a battery container manufactured by the battery container manufacturing method, and a battery using the battery container.

The battery container manufacturing method of the present invention has the following characteristics.
(1) After performing nickel or nickel alloy plating on both surfaces of the steel plate, the steel plate is molded into a bottomed cylindrical shape, and further, the outer surface portion including the cylindrical bottomed portion has a thickness of 0.1 to 3 μm. Nickel plating or nickel alloy plating is performed.
(2) After performing nickel or nickel alloy plating on both surfaces of the steel plate, the steel plate is subjected to a thermal diffusion treatment to form an iron-nickel diffusion layer between the nickel plating layer and the steel plate, thereby forming a bottomed cylindrical shape. It is characterized in that the nickel plating or nickel alloy plating with a thickness of 0.1 to 3 μm is performed only on the outer surface portion which is molded and further includes a bottom portion having a cylindrical shape.
(3) In the above (1) or (2),
The thickness of nickel or nickel alloy plating performed on both surfaces of the steel sheet is 0.1 to 1.5 μm.
(4) In any one of the above (1) to (3),
Nickel or nickel alloy plating is performed only at a portion where a battery can of a steel plate is formed.
(5) In any one of the above (1) to (4),
The nickel alloy plating is nickel-cobalt alloy plating, nickel-cobalt-phosphorus alloy plating, nickel-manganese alloy plating, nickel-iron alloy plating, nickel-phosphorus alloy plating, or nickel-boron alloy plating.
(6) In any of (1) to (5) above,
The outer surface portion including the cylindrical bottomed portion includes a pip portion.

(7) The battery container of the present invention is manufactured by the method for manufacturing a battery container according to any one of (1) to (6) above.
(8) The battery of the present invention is characterized by using the battery container described in (7) above.

  The battery container of the present invention is formed into a bottomed cylindrical shape after thinly nickel or nickel alloy plating on both sides of the steel sheet or after heat diffusion heat treatment after thinly nickel or nickel alloy plating In addition, since nickel plating is applied to the outer surface of the cylindrical shape or a part on the outer surface side where further corrosion resistance is required, it is possible to provide a battery container manufacturing method that is inexpensive and excellent in corrosion resistance.

  The contents of the present invention will be described below. As the steel plate used as the substrate of the battery container of the present invention, general-purpose low carbon aluminum killed steel (carbon content 0.01 to 0.15 wt%), or non-aging ultra low carbon aluminum killed steel to which niobium or titanium is added ( Carbon amount of less than 0.01% by weight). These steel hot-rolled sheets are pickled to remove surface scales, then cold-rolled, and then subjected to electrolytic cleaning, annealing, and temper rolling as a substrate. Further, after cold rolling and electrolytic cleaning after nickel or nickel alloy plating, a heat treatment that doubles as a recrystallization annealing of the steel substrate and a diffusion treatment of the plating layer may be performed simultaneously.

  First, nickel or nickel alloy plating is applied to both surfaces of a steel plate as a substrate. Nickel or nickel alloy plating is preferably matte plating or semi-gloss plating obtained by plating using a bath containing an organic brightener in a matte plating bath. As the plating bath, a commonly used watt bath, sulfuric acid bath, chloride bath, or the like can be used. Bright plating using a bath containing an organic brightener containing a sulfur component is not preferred because heating after plating results in brittleness of the coating due to the sulfur component and a decrease in corrosion resistance. The plating amount is preferably 0.1 to 1.5 μm as nickel. If the thickness as nickel is less than 0.1 μm, the corrosion resistance on the inner surface of the battery can is insufficient, and the battery performance is deteriorated. On the other hand, when the thickness exceeds 1.5 μm, the effect of improving the corrosion resistance or the effect of improving the battery performance except for the pip portion reaches saturation and becomes uneconomical.

  As the nickel alloy plating, nickel alloy plating to which cobalt, iron or manganese is added can be applied. The content of cobalt, iron or manganese is preferably 20% by weight or less in the plating layer. Exceeding 20% by weight is not preferable in that the price increases.

  Further, nickel or nickel alloy plating may be performed only at a portion where a battery container of a steel plate is formed. When processing into the cylindrical shape of the target electric container, plating is partially performed in accordance with the size and shape of the blank diameter to be punched. In this case, the plating thickness may be partially changed. The portion where the battery container is not formed has few impurity metals other than iron such as nickel when discarded as scrap, and can be regenerated at low cost when recycled for reuse. In addition, it is possible to thick plate only the portion corresponding to the battery container.

  The battery container may be molded with the nickel or nickel alloy plating applied, but subsequently, after the plating, a thermal diffusion treatment is performed using a box-type annealing method or a continuous annealing method in a protective gas atmosphere. When using a box-type annealing method, it is preferable to soak for 1 to 15 hours in a temperature range of 500 to 650 ° C. When using a continuous annealing method, heating is performed for 10 seconds to 3 minutes at a temperature range of 600 to 850 ° C. Is preferred. By performing thermal diffusion treatment under such conditions, the iron-nickel (alloy) diffusion layer or the iron-nickel (alloy) diffusion layer at the interface between the steel substrate and the nickel plating layer is recrystallized and softened. A nickel layer is formed. In particular, when an iron-nickel (alloy) diffusion layer and a nickel layer softened by recrystallization are formed thereon, it is desirable in terms of corrosion resistance after being molded into a battery container.

  After performing any of the thermal diffusion treatments in this manner, temper rolling is performed at a rolling rate of 2% or less in order to prevent the occurrence of stretch yarn strain. More desirably, temper rolling is performed at a rolling rate of less than 1.3%.

  For steel plates manufactured as described above, use a deep drawing method, drawing ironing method (DI processing method), drawing stretch processing method (DTR processing method), or a processing method that combines ironing with stretching after drawing. To form a bottomed cylindrical shape. As the cylindrical shape, the bottom surface is a circle, an ellipse, or a polygonal shape such as a rectangle or a square, and is molded into a cylindrical shape with the side wall height appropriately selected according to the application. Thus, the battery container shape | molded in the cylinder shape performs nickel or nickel alloy plating only on the bottom part of a battery container outer surface or an outer surface side. In the case of a battery container having a pip part, nickel or nickel alloy plating is performed only on the bottomed part including the pip part. The nickel or nickel alloy plating is preferably performed by electroless plating or electrolytic plating. In the case of electrolytic plating, semi-gloss or bright plating containing a brightening agent in the plating solution may be performed, or matte plating containing no brightening agent can be applied. As the nickel alloy plating, nickel-phosphorus alloy plating, nickel-boron alloy plating, nickel-cobalt alloy plating, nickel-cobalt-phosphorus alloy plating, nickel-manganese alloy plating, nickel-iron alloy plating, or nickel-tin alloy plating can be applied. The content of phosphorus, boron, cobalt, manganese, iron or tin during plating is preferably 20% or less. More desirably, it is 5% or less. Even if it exceeds 20% or more, there is no influence on the characteristics, but if an expensive metal such as cobalt is applied, it is not economical. Nickel-phosphorus alloy plating or nickel-boron alloy plating can be applied even by electroless plating. The thickness of the nickel or nickel alloy plating is preferably 0.1 to 3 μm. If it is less than 0.1 μm, the corrosion resistance on the outer surface side of the battery container is insufficient, and conversely if it exceeds 3 μm, the corrosion resistance is saturated, which is not economical. The battery container thus obtained is filled with a positive electrode mixture, a negative electrode active material, and the like to obtain a battery.

Hereinafter, the present invention will be described in detail with reference to examples.
[Creation of plated steel sheets for battery containers]
As a substrate, a cold rolled sheet having a thickness of 0.25 mm or 0.4 mm made of low carbon aluminum killed steel (I) or extremely low carbon aluminum killed steel (II) whose chemical composition is shown in Table 1 is used. Washing and pickling were performed, and nickel or nickel alloy plating was performed. In the case of annealing after cold rolling, in the case of low carbon aluminum killed steel (I), it was soaked at 640 to 660 ° C. for 8 hours by box annealing. In the case of extremely low carbon aluminum killed steel (II), after cold rolling, it was heated at 650-850 ° C. for 1-2 minutes by continuous annealing. Further, in the case of the ultra-low carbon aluminum killed steel (II), the annealing and thermal diffusion treatment by continuous annealing can be performed after nickel or nickel alloy plating without performing the annealing after cold rolling.

Nickel plating, nickel-cobalt alloy plating, and nickel-iron plating were performed under the following conditions.
<Nickel plating>
Bath composition Nickel sulfate 300g / L
Nickel chloride 40g / L
Boric acid 40g / L
Pit inhibitor (sodium lauryl sulfate) 0.4mL / L
Anode Nickel pellet (filled in titanium basket)
Stirring Air stirring pH 4 to 4.6
Bath temperature 55-60 ° C
Current density 20A / dm2

<Nickel-cobalt alloy plating>
Bath composition Nickel sulfate 300g / L
Nickel chloride 40g / L
Cobalt sulfate (added as appropriate)
Boric acid 40g / L
Pit inhibitor (sodium lauryl sulfate) 0.4mL / L
Anode Nickel pellet (filled in titanium basket)
Stirring Air stirring pH 4 to 4.6
Bath temperature 55-60 ° C
Current density 20A / dm2

<Nickel-iron alloy plating>
Bath composition Nickel sulfate 300g / L
Nickel chloride 40g / L
Iron sulfate (added as appropriate)
Boric acid 40g / L
Pit inhibitor (sodium lauryl sulfate) 0.4mL / L
Anode Nickel pellet (filled in titanium basket)
Stirring Air stirring pH 4 to 4.6
Bath temperature 55-60 ° C
Current density 20A / dm2

When diffusion treatment is performed after nickel or nickel alloy plating, the thermal diffusion treatment is performed in the case of low carbon aluminum killed steel (I) by soaking at 500 to 560 ° C. for 6 to 8 hours by box annealing, and the low carbon aluminum killed steel (I) In the case of a part of and a very low carbon aluminum killed steel (II), it was heated at 650 to 820 ° C. for 30 seconds to 3 minutes by continuous annealing.

The battery container samples (sample numbers 1 to 8) shown in Table 2 were prepared as described above. For comparison, the steel plate was not plated, and a battery container (Sample No. 9) in which bright nickel plating was applied to the outer surface side and 3 μm plating was performed after the battery container was processed. For comparison, a semi-bright nickel plating was applied to the surface corresponding to the outer surface of the steel plate by 2 μm, and the surface corresponding to the inner surface was applied by 1 μm, followed by diffusion treatment. No. 10), and a battery container (sample number) in which the matte nickel plating is applied to the surface corresponding to the outer surface of the steel plate by 2.3 μm and the surface corresponding to the inner surface is 1.2 μm, and the battery container is not plated after being processed. 11) was created. The battery container is created as follows.
[Create battery container]
After blanks are punched from these samples Nos. 1 to 11, the outer diameter is 13.8 mm using a deep drawing method, a drawing and ironing method (DI processing method), or a drawing stretch processing method (DTR processing method). Then, it was molded into a cylindrical LR6 battery (AA battery) container having a height of 49.3 mm.
<Deep drawing processing conditions>
The battery container is manufactured by a deep drawing method using a plated steel sheet having a thickness of 0.25 mm, punched to a blank diameter of 57 mm, drawn several times, and redrawed to an outer diameter of 13.8 mm, a container side wall of 0.25 mm, and a high A 49.3 mm LR6 type battery container was produced.
<Drawing and ironing conditions>
The battery container is manufactured by the DI processing method using the above plated steel plate with a thickness of 0.4 mm, cupping from a blank diameter of 41 mm to a diameter of 20.5 mm, and then performing a redo and two-stage ironing with a DI molding machine. The outer diameter was 13.8 mm, the container side wall was 0.20 mm, and the height was 56 mm. Finally, the upper part was trimmed to produce an LR6 type battery container having a height of 49.3 mm.
<Drawing stretch processing (DTR processing) conditions>
The battery container is manufactured by the DTR processing method using a plated steel sheet having a thickness of 0.25 mm, punched to a blank diameter of 58 mm, drawn several times, and redrawed to an outer diameter of 13.8 mm, a container side wall of 0.20 mm, and a height. A 49.3 mm LR6 type battery container was produced.

As described above, after manufacturing the battery container, the following nickel or nickel alloy plating was applied to the bottomed part having the pip part on the outer surface side of the battery container. Table 2 shows the barrel plating. Nickel-phosphorus alloy plating was performed under the following conditions. Nickel plating was performed under the above-described plating conditions.
<Nickel-phosphorus alloy plating>
Bath composition Nickel sulfate 240g / L
Nickel chloride 40g / L
Boric acid 30g / L
Phosphorous acid 8g / L
Anode Nickel pellet (filled in titanium basket)
Stirring Air stirring bath temperature 40-45 ° C
Current density 8A / dm2

[Create battery]
Using this battery container, an alkaline manganese battery was prepared as follows. Manganese dioxide and graphite were collected at a ratio of 10: 1, and potassium hydroxide (10 mol) was added and mixed to prepare a positive electrode mixture. Next, the positive electrode mixture was pressurized in a mold to form a donut-shaped positive electrode mixture pellet with a predetermined size, and was press-inserted into the battery container. In addition, some battery containers used what applied the coating material which has graphite powder as a main component on the inner surface. Next, the negative electrode plate spot-welded with the negative electrode current collector rod was attached to the battery container. Next, a separator made of vinylon woven fabric is inserted along the inner circumference of the positive electrode mixture pellet inserted into the battery container, and a negative electrode gel made of potassium hydroxide saturated with zinc particles and zinc oxide is added to the battery. The container was filled. Further, an insulating gasket was attached to the negative electrode plate and inserted into the battery container, followed by caulking to prepare an alkaline manganese battery.

[Characteristic evaluation]
The characteristics of the batteries prepared using the battery containers prepared from the samples Nos. 1 to 11 as described above were evaluated as follows.

<Internal resistance>
The battery was left at 80 ° C. for 3 days, and then the internal resistance value (mΩ) was measured by the AC impedance method. The smaller the internal resistance value, the better the characteristics.

<Short-circuit current>
After leaving the battery at 80 ° C. for 3 days, an ammeter was connected to the battery, a closed circuit was provided, and the current value was measured, which was defined as a short-circuit current. It shows that a characteristic is so favorable that a short circuit current is large.

<Discharge characteristics>
After leaving the battery at 80 ° C. for 3 days, the battery was discharged to a constant current of 1.5 A, and the time until the voltage reached 0.9 V was measured as the discharge time. The longer the discharge time, the better the discharge characteristics.

<Corrosion resistance>
The battery was allowed to stand for 2.5 hours in a salt spray test (SST), and the occurrence of red rust on the bottomed part (including the pip-processed part) of the battery was examined. The case where the number of rust generations was 0 to 5 / battery was evaluated as ◯, the case of 6 to 10 / battery was evaluated as Δ, and the case of 11 or more / battery was evaluated as ×. Only ○ was considered acceptable.

  As shown in Table 3, the battery of the present invention is excellent in discharge characteristics and corrosion resistance as compared with a battery (Comparative Example 1) in which plating is not performed in the state of a steel sheet and plating is performed on the battery container. Moreover, it has the same discharge characteristics as batteries (Comparative Examples 2 and 3) in which the battery container is not plated after processing, and has excellent battery flowability and corrosion resistance.

After nickel or nickel alloy plating with a thickness of 0.1 to 1.5 μm is applied to both surfaces of the steel sheet, it is molded into a battery container having a bottomed part, and further to the bottomed part (including the pip part) on the outer surface side of the battery container. Batteries made with nickel or nickel alloy plating with a thickness of 0.1 to 3 μm and filled with negative electrode agent and positive electrode agent etc. are equivalent in short circuit current and discharge characteristics compared to batteries made without plating after forming the battery container And has excellent battery flowability and corrosion resistance.
Thus, a battery in which only a bottomed portion requiring corrosion resistance is plated after the battery container is molded is a cheaper battery.

Claims (8)

After performing nickel or nickel alloy plating on both surfaces of the steel plate, it is molded into a bottomed cylindrical shape, and further , nickel plating with a thickness of 0.1 to 3 μm or only on the outer surface including the bottomed portion of the cylindrical shape The manufacturing method of the battery container characterized by performing nickel alloy plating. After nickel or nickel alloy plating is performed on both sides of the steel plate, the steel plate is subjected to a thermal diffusion treatment to form an iron-nickel diffusion layer between the nickel plating layer and the steel plate, and then formed into a cylindrical shape with a bottom. Furthermore , a nickel container or nickel alloy plating having a thickness of 0.1 to 3 μm is performed only on an outer surface portion including a bottom portion having a cylindrical shape. The method for manufacturing a battery container according to claim 1 or 2, wherein a thickness of nickel or nickel alloy plating performed on both surfaces of the steel plate is 0.1 to 1.5 µm. The said nickel or nickel alloy plating is performed only in the location which forms the battery can of a steel plate, The manufacturing method of the battery container in any one of Claims 1-3 characterized by the above-mentioned. Claim phosphorus alloy plating, nickel-manganese alloy plating, nickel-iron alloy plating, characterized in that it is a nickel-phosphorus alloy plating or nickel-boron alloy plating - said nickel alloy plating, nickel-cobalt alloy plating, nickel - cobalt The manufacturing method of the battery container in any one of 1-4 . The method for manufacturing a battery container according to any one of claims 1 to 5, wherein the outer surface portion including the bottom portion having the cylindrical shape includes a pip portion. The battery container manufactured by the manufacturing method of the battery container in any one of Claims 1-6 . A battery comprising the battery container according to claim 7.