JPH07302581A - Alkaline battery - Google Patents

Abstract

PURPOSE:To enhance performance and reduce production cost by using a copper- tin alloy in a negative pole can. CONSTITUTION:The outside 9 and inside 10 of a negative pole can of a silver battery are formed with an alloy comprising copper and tin in place of a nickel- stainless steel-copper three layer clad material to prevent the bulging of battery container caused by generation of hydrogen gas and deterioration in shelf life. A negative pole can core material formed of iron or brass and a copper-tin alloy layer is formed on the surface of the negative pole can to reduce production cost. After forming of the can, since the copper-tin alloy layer is formed by plating or vapor deposition, power of metal such as stainless steel and iron is not exposed on the surface of the inside 10. Since the copper-tin alloy layer is difficult to form on the inside 12 of turning up part of the negative pole can, when press forming is conducted after forming of the alloy layer, the core material is exposed at the negative pole can end 11. If the exposed metal is stainless steel or brass, corrosion is not produced, but if it is iron, care must be taken in environment for use, such as the inside of an appliance. By use of the copper-tin alloy, cost can be reduced.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a button type or coin type alkaline battery in which zinc or zinc alloy powder is used as a negative electrode active material and silver oxide, manganese dioxide, oxygen or the like is used as a positive electrode active material.

2. Description of the Related Art Most of negative electrode cans used in alkaline batteries are press-molded three-layer clad materials of nickel, stainless steel and copper.

Many of the negative electrode cans used in alkaline batteries are press-molded three-layer clad materials of nickel, stainless steel, and copper. The three-layer clad material of nickel, stainless steel, and copper has a problem that it is an expensive material. When a three-layer clad material was used, cutting powder of stainless steel or iron powder from a steel tool sometimes adhered to the copper surface during molding. The metal powder such as stainless steel and iron attached to the copper surface which is the current collector has a small hydrogen overvoltage, and therefore contacts zinc and forms a local battery to generate hydrogen gas. Therefore, it has caused defects such as swelling of the battery can and deterioration of storage capacity.

[Means for Solving the Problems] The outer side 9 and the inner side 10 of the negative electrode can of the silver battery shown in FIG.
The above problems can be solved by using an alloy containing tin as a main component and not using a three-layer clad material of nickel, stainless steel, and copper. As a concrete solution, a material obtained by press-molding a strip material of an alloy containing copper and tin as a main component may be used. Further, by manufacturing the negative electrode can core material formed of stainless steel, iron or brass and using the negative electrode can on the surface of which the alloy layer containing copper and tin as a main component is provided, the manufacturing cost can be significantly reduced. Further, according to this method, since the copper / tin alloy layer is formed on the surface after the can is formed by a method such as plating or vapor deposition, metal powder such as stainless steel or iron is not exposed on the outermost surface of the inside 10 of the negative electrode can. However, it is difficult to provide an alloy layer containing copper and tin as a main component in the folded inside 12 of the negative electrode can. When the band-shaped material is provided with an alloy layer containing copper and tin as a main component and then press-molded, the core material is exposed at the negative electrode can end 11. Negative electrode can folded inside 1
2. If the metal exposed at the negative electrode can end 11 is stainless steel or brass, there is no problem of corrosion. When the exposed metal is iron, it is desirable to use the battery in an environment such as the inside of the equipment that is unlikely to corrode. Significant cost reduction can be achieved by changing the three-layer clad material of nickel, stainless steel, and copper to an inexpensive material.

[Function] Copper-tin alloy has good corrosion resistance and little increase in contact resistance between the negative electrode can and the lead terminal. Further, since the hydrogen overvoltage is larger than that of copper conventionally used as the inside of the negative electrode can, even if it contacts zinc, which is the negative electrode active material, less gas is generated, and mercury is also apt to undergo this process. As the negative electrode active material,
Bismuth, indium, aluminum, calcium,
The same effect can be obtained by using either anhydrous zinc-zinc containing lead, gallium, or the like in the range of several tens to several hundreds of ppm or zinc iodide. The outer and inner surfaces of the negative electrode can are made of an alloy containing copper and tin as main components,
The above problem can be solved by not using the three-layer clad material of nickel, stainless steel, and copper. It is also effective to further provide an organic film such as a water repellent agent on the surface of the alloy containing copper and tin as a main component. The organic coating prevents corrosion of the alloy on the outside of the negative electrode can and suppresses an increase in contact resistance. On the inner side, the electrolyte is prevented from leaking out to the outside of the battery can. As a specific solution, it is possible to use a press-molded plate material of an alloy containing copper and tin as a main component. In this case, there is a problem in that the strength of the can is reduced and the cutting powder at the time of molding and the adhesion of iron powder from the steel tool. The decrease in strength can be solved by making the plate material a little thicker, and the adhesion of cutting powder or iron powder from steel tools can be solved by cleaning the negative electrode can with acid or chemical polishing. In this case, it is desirable to use sulfuric acid and hydrochloric acid as the acid. Nitric acid is preferably used at a relatively low concentration, but when it is at a high concentration, it becomes more oxidative and damages the alloy containing copper and tin as the main component. Acid concentration is 10
It is desirable to immerse it in about 50% for several tens of seconds to several minutes. For example, when the acid concentration is A% by weight and the immersion time is B minutes, a sufficient effect can be obtained by setting the value of A × B to be 10 or more. Since the adhesion state of impurities differs depending on the negative electrode can used, the proper concentration and the immersion time may be determined for each production lot by a gas generation test as described below. The acid treatment temperature is from room temperature to 80 ° C. in the case of sulfuric acid, and room temperature because hydrochloric acid has a strong volatility. For chemical polishing,
Hydrogen peroxide water (hydrogen peroxide water in the present invention is defined as containing about 25 to 35% by weight of hydrogen peroxide available as a general reagent) 25 to 80 vol%, sulfuric acid 0.01 to 1 vol%, alcohol It is possible to remove metal powder such as stainless steel and iron adhered to the copper-tin alloy surface by immersing in a liquid consisting of 5 to 40 vol% remaining water and then immersing in acid. Furthermore, the surface of the copper-tin alloy increases in gloss and becomes flat, so that liquid leakage resistance is also improved. In the gas generation test, after putting the electrolyte solution into the negative electrode can with a Komagome pipette just before spilling, put several tens of anhydrous silver zinc particles of 100 to 200 mesh size, and observe bubbles generated in the negative electrode can with a stereoscopic microscope. By the method. When metal powder such as stainless steel or iron adheres to the negative electrode can, gas bubbles are generated from the metal powder. Further, by manufacturing a negative electrode can core material press-molded from stainless steel, iron or brass and using a negative electrode can having an alloy layer containing copper and tin as a main component on the surface, the manufacturing cost can be significantly reduced. Furthermore, with this method, copper can be
Since the alloy layer containing tin as a main component is formed by a method such as plating or vapor deposition, metal powder such as stainless steel or iron is not exposed on the outermost surface of the inside 10 of the negative electrode can. The plating method is the most efficient method for forming an alloy layer containing copper and tin as a main component on the surface after can forming. It is also effective to plate copper / tin with zinc or nickel for the purpose of improving gloss and corrosion resistance. Stainless steel and iron have a small hydrogen overvoltage, and when exposed to the surface, gas generation occurs in the battery, which causes defects such as swelling and leakage of the battery. When stainless steel or iron is used as the core material, plating with nickel or copper once, and then plating with an alloy layer containing copper or tin as the main component can improve the adhesion of the alloy layer, resulting in film defects. Can be reduced. When stainless steel is used as the core material, it is also important to physically or chemically remove the oxide film on the surface before plating to improve adhesion and reduce defects in the film. There is also a method of plating nickel or copper on a metal as a core material in a hoop state before forming a can. In this case, there is an advantage that it is easy to control the thickness of nickel or copper. Stainless steel used as the core material is JIS SUS304, SUS430
Etc. Iron is used for SPC drawing, deep drawing, etc. For brass, JIS C2100, C2200, C2300, C24
00, C2600, C2680, C2720, C280
1, C3560, C3561, C3710, C371
3, C4250, C4430, C4621, C4640
Etc. may be used. Normally, alloys in the C2000 series may be used, but high strength C3000 series may be used for large size batteries, and C4000 series high corrosion resistance may be used for batteries that may be used in corrosive environments. . For plating, Bronzex W-1 manufactured by Nippon Electroplating Engineers Co., Ltd. with a white and glossy copper-tin ratio of 0.6: 1, and a pale yellow copper-tin ratio of 3.3. There are Bronzex II of 1: 1 and Bronzex G-1 of golden color with a copper to tin ratio of 5: 1. A negative electrode can whose surface is an alloy containing copper and tin as a main component can reduce mercury, which is a pollutant, or can be converted to anhydrous silver in order to reduce defects such as liquid leakage and swelling. By changing the material of the present invention from a three-layer clad material of nickel, stainless steel, and copper as the hoop material, which is the raw material of the negative electrode can, the energy during production can be significantly reduced.

EXAMPLES The present invention will be described below with reference to examples. <Example 1> Cold of JIS SPCE of 0.2 mm thickness
SR626SW size negative electrode by pressing rolled steel strip
10,000 cans were produced. Next, sodium orthosilicate 30
Alkaline degreasing liquid at 60 ° C with g / l and surfactant 3g / l
Make 10000 ml of the
Place in a horizontal barrel made of ril and rotate at 40 rpm for 20 minutes.
After degreasing and cleaning, the product was washed with running water for 30 seconds. next
Sulfuric acid concentration of 10 vol% as it is in the barrel, a few minutes in a liquid of 60 ℃
Immerse, rinse with running water for 3 minutes, and finally with pure water
Then, acid cleaning was performed and plating was performed. Below
Describe the conditions. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Manufactured by: Temperature: 55 ° C Current density: 3 A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was <Example 2> JIS SUS304 having a thickness of 0.2 mm
SR626SW size by pressing a stainless steel strip
10,000 negative electrode cans were produced. Next, sodium orthosilicate
Alkali at 60 ° C with 30 g / l of surfactant and 3 g / l of surfactant
Make 10,000 ml of degreasing liquid and 500 ml of negative electrode can
Place it in a horizontal acrylic barrel for 20 minutes at 40 rpm
After rotating and degreasing cleaning, rinse with running water for 30 seconds.
It was Next, remove and activate the oxide film on the stainless steel.
went. Sulfuric acid concentration of 20vol% at 70 ℃
The liquid does not violently generate gas, and gas is generated uniformly.
Soaked in. Furthermore, 5 A in a liquid with a sulfuric acid concentration of 50 vol%
/ Dm² The cathode treatment was performed for 5 minutes. Rinse with running water for 3 minutes
Finally, the plate was washed with pure water and then plated. Below
Write down the conditions. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Manufactured by: Temperature: 55 ° C Current density: 3 A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was <Example 3> 0.2 mm thick JIS C2100 brass
Press the strip to make a SR626SW size negative electrode can.
Ten thousand were produced. Next, sodium orthosilicate 10 g /
1, sodium hydroxide 10g / l, sodium carbonate 30
Alkaline degreasing liquid at 80 ° C with g / l and surfactant 3g / l
Make 10000 ml of the
Put in a horizontal barrel made of ril and rotate at 40 rpm for 2 minutes.
Cathode current density 5A / dm ² After performing electrolytic degreasing cleaning with
It was washed with running water for 30 seconds. Next, leave the barrel with sulfuric acid concentration 4
Immerse in 0vol%, 80 ° C liquid for 10 minutes, and then with running water
Rinse with water for 3 minutes and finally with pure water
It was purified and plated. The plating conditions are described below. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Company temperature: 55 ° C Current density: 3A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was <Example 4> Cold of JIS SPCE of 0.2 mm in thickness
SR626SW size negative electrode by pressing rolled steel strip
10,000 cans were produced. Next, sodium orthosilicate 30
Alkaline degreasing liquid at 60 ° C with g / l and surfactant 3g / l
Make 10000 ml of the
Place in a horizontal barrel made of ril and rotate at 40 rpm for 20 minutes.
After degreasing and cleaning, the product was washed with running water for 30 seconds. next
Sulfuric acid concentration of 10 vol% as it is in the barrel, a few minutes in a liquid of 60 ℃
Immerse, rinse with running water for 3 minutes, and finally with pure water
The acid cleaning was performed by the procedure of performing. Then nickel barrel
The plating was performed under the following conditions. Plating solution composition: Nickel chloride 240g / l Hydrochloric acid 120g / l Temperature: Room temperature Current density: 10A / dm² Time: 3 minutes Copper / tin plating was further performed under the following conditions. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Manufactured by: Temperature: 55 ° C Current density: 3 A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was <Example 5> Cold of JIS SPCE of 0.2 mm thickness
SR626SW size negative electrode by pressing rolled steel strip
10,000 cans were produced. Next, sodium orthosilicate 30
Alkaline degreasing liquid at 60 ° C with g / l and surfactant 3g / l
Make 10000 ml of the
Place in a horizontal barrel made of ril and rotate at 40 rpm for 20 minutes.
After degreasing and cleaning, the product was washed with running water for 30 seconds. next
Sulfuric acid concentration of 10 vol% as it is in barrel
Immerse, rinse with running water for 3 minutes, and finally with pure water
The acid cleaning was performed by the procedure of performing. Then copper barrel plating
Was performed under the following conditions. Plating solution composition: Cuprous cyanide 50 g / l Sodium cyanide 20 g / l Potassium hydroxide 10 g / l Temperature: 50 ° C. Current density: 3 A / dm² Time: 3 minutes Copper / tin plating was further performed under the following conditions. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Manufactured by: Temperature: 55 ° C Current density: 3 A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was <Example 6> Cold of JIS SPCE of 0.2 mm in thickness
Hoop plating of 3μm nickel on both sides of rolled steel strip
Press the No. to make a SR626SW size negative electrode can.
10,000 pieces were produced. Next, sodium orthosilicate 30g /
l, 1g of alkaline degreasing liquid at 60 ° C with 3g / l of surfactant
0000ml made, negative electrode can with 500ml acrylic
Put it in a horizontal barrel made of steel and rotate it at 40 rpm for 20 minutes to remove it.
After the oil was washed, it was washed with running water for 30 seconds. Then the following
The activation process of nickel was performed by the above method. Activating solution: Sulfuric acid 10 vol% Anodic treatment: 3 A / dm² , 30 seconds Cathodic treatment: 3 A / dm² 2 seconds After activation, rinse with running water for 3 minutes and finally with pure water
Plated with copper and tin. The plating conditions are described below. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Manufactured by: Temperature: 55 ° C Current density: 3 A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was <Example 7> 0.2 mm thick JIS SPCE cold work
Use hoop plated 3μm copper on both sides of rolled steel strip.
10,000 pieces of SR626SW size negative electrode cans by press working
It was made. Next, sodium orthosilicate 30g / l,
1000g of alkaline degreasing liquid at 60 ℃ with 3g / l surfactant
Make 0 ml, and put the negative electrode can into a 500 ml acrylic side.
Put in mold barrel and rotate at 40 rpm for 20 minutes to degrease and wash
After that, it was washed with running water for 30 seconds. Next method
The copper activation treatment was performed. Hydrogen peroxide water (reagent special grade 3
0 wt%) 150 g, sulfuric acid (special grade 97 wt%)
4 g, ethanol (special grade reagent) 40 g, water (pure water) 20
A solution consisting of 0 g and an aqueous solution of about 10 wt% sulfuric acid B
500 ml of the liquid was prepared. The temperature of the liquid is room temperature for both A and B.
did. The negative electrode can was quickly put in the liquid A and immersed for a predetermined time.
Negative electrode in which a uniform candy-colored copper oxide film was formed by immersion in solution A
After washing the can with running water, soak it in solution B for 1 minute to remove the copper oxide film.
Has a lustrous activated copper surface by melting
It was possible to obtain a negative electrode can. After the activation treatment, 3 with running water
Rinse with water for a minute, and finally with pure water and apply copper / tin plating
It was The plating conditions are described below. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Manufactured by: Temperature: 55 ° C Current density: 3 A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was <Example 8> JIS SUS304 having a thickness of 0.2 mm
SR626SW size by pressing a stainless steel strip
10,000 negative electrode cans were produced. Next, sodium orthosilicate
Alkali at 60 ° C with 30 g / l of surfactant and 3 g / l of surfactant
Make 10,000 ml of degreasing liquid and 500 ml of negative electrode can
Place it in a horizontal acrylic barrel for 20 minutes at 40 rpm
After rotating and degreasing cleaning, rinse with running water for 30 seconds.
It was Next, remove and activate the oxide film on the stainless steel.
went. Sulfuric acid concentration of 20vol% at 70 ℃
The liquid does not violently generate gas, and gas is generated uniformly.
Soaked in. Furthermore, 5 A in a liquid with a sulfuric acid concentration of 50 vol%
/ Dm² The cathode treatment was performed for 5 minutes. 3 minutes with running water
The activation process is performed by washing with cold water and finally with pure water.
It made sense. Next, nickel barrel plating under the following conditions
went. Plating solution composition: Nickel chloride 240g / l Hydrochloric acid 120g / l Temperature: Room temperature Electrolysis conditions: 2 minutes, 2A / dm² After anodizing with
4 minutes, 2 A / dm² Plated. Further, copper / tin plating was performed under the following conditions. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Manufactured by: Temperature: 55 ° C Current density: 3 A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was <Example 9> JIS SUS304 having a thickness of 0.2 mm
SR626SW size by pressing a stainless steel strip
10,000 negative electrode cans were produced. Next, sodium orthosilicate
Alkali at 60 ° C with 30 g / l of surfactant and 3 g / l of surfactant
Make 10,000 ml of degreasing liquid and 500 ml of negative electrode can
Place it in a horizontal acrylic barrel for 20 minutes at 40 rpm
After rotating and degreasing cleaning, rinse with running water for 30 seconds.
It was Next, remove and activate the oxide film on the stainless steel.
went. Sulfuric acid concentration of 20vol% at 70 ℃
The liquid does not violently generate gas, and gas is generated uniformly.
Soaked in. Furthermore, 5 A in a liquid with a sulfuric acid concentration of 50 vol%
/ Dm² The cathode treatment was performed for 5 minutes. 3 minutes with running water
The activation process is performed by washing with cold water and finally with pure water.
It made sense. Next, copper barrel plating is performed under the following conditions.
It was Plating solution composition: Cuprous cyanide 50 g / l Sodium cyanide 20 g / l Potassium hydroxide 10 g / l Temperature: 50 ° C. Current density: 3 A / dm² Time: 3 minutes Copper / tin plating was further performed under the following conditions. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Manufactured by: Temperature: 55 ° C Current density: 3 A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was <Example 10> JIS SUS304 having a thickness of 0.2 mm
Hoop 3 μm nickel on both sides of the stainless steel strip
Press the pressed ones into SR626SW size
10,000 negative electrode cans were produced. Then sodium orthosilicate
Alkaline removal at 60 ° C with 30 g / l and 3 g / l of surfactant
Make 10000ml of oil and 500ml of negative electrode can.
Place in an acrylic horizontal barrel and rotate at 40 rpm for 20 minutes.
After tumbling and degreasing and washing, it was washed with running water for 30 seconds.
Next, nickel activation treatment was performed by the following method. Activating solution: Sulfuric acid 10 vol% Anodic treatment: 3 A / dm² , 30 seconds Cathodic treatment: 3 A / dm² , 2 seconds After activation, rinse with running water for 3 minutes and finally with pure water
Plated with copper and tin. The plating conditions are described below. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Manufactured by: Temperature: 55 ° C Current density: 3 A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was <Example 11> JIS SUS304 having a thickness of 0.2 mm
Hoop plating of 3μm copper on both sides of the stainless steel strip
SR626SW size negative electrode can by pressing
10,000 were produced. Next, sodium orthosilicate 30g
/ L, 3g / l of surfactant and 60 ° C alkaline degreaser
Make 10000 ml and add a negative electrode can to a volume of 500 ml.
Put in a horizontal barrel made of le and rotate at 40 rpm for 20 minutes
After degreasing and washing, it was washed with running water for 30 seconds. Next
Sulfuric acid concentration 40 vol% as it is, 10 minutes in a liquid at 80 ° C
Immerse, rinse with running water for 3 minutes, and finally with pure water
Then, acid cleaning was performed and plating was performed. Below
Describe the conditions. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Manufactured by: Temperature: 55 ° C Current density: 3 A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was Eliminate defects in the intermediate copper and nickel layers and
Hoop plating to prevent exposure of iron and iron
Formed by rolling or intermediate layer cladding
It is also effective to use materials. Remove defects in the middle copper layer
Comb, hoop to eliminate exposed stainless steel or iron
After plating, rolled or clad with intermediate copper
It is also effective to use materials. <Example 12> The ratio of copper to tin having a thickness of 0.2 mm is 4: 6.
SR626SW size negative electrode by pressing the bronze band of
10,000 cans were produced. Next, sodium orthosilicate 10
g / l, sodium hydroxide 10g / l, sodium carbonate
Alkaline desorption at 80 ° C with 30 g / l and 3 g / l of surfactant
Make 10000ml of oil and 500ml of negative electrode can.
Place in an acrylic horizontal barrel and rotate at 40 rpm for 2 minutes
Let cathode current density 5A / dm² Electrolytic degreasing was performed with
Then, it was washed with running water for 30 seconds. Next, leave the barrel with concentrated sulfuric acid
Immerse in liquid of 80 vol.
Wash with water for 3 minutes and finally with pure water.
An acid wash was performed. Plating was also performed if necessary. Below
Write down the conditions. Plating solution: Bronzex W-1 Japan Electroplating Engineers Co., Ltd.
Manufactured by: Temperature: 55 ° C Current density: 3 A / dm² Deposition rate: 0.7 μm / min The plated negative electrode can was washed with running water for 3 minutes with the barrel still.
Then, it was washed with pure water for 3 minutes. Next, a tank containing methanol
2 tanks were prepared. Soak each tank for 3 minutes with shaking.
Replace the water on the surface of the negative electrode can with methanol.
It was After replacement, the methanol content is roughly dried by centrifugation.
Then, put it in a drying oven heated to 50 ° C and dry for 15 minutes.
did. Check the thickness of the plating film with a fluorescent X-ray device.
It was Level of plating thickness of copper-tin alloy of Examples 1 to 12
Was 0, 0.5, 1, 3, 4 μm. Evaluation of negative electrode can
Use a Komagome pipette until the electrolyte spills into the negative electrode can.
After pouring, 100-200 mesh size anhydrous silver
Open cells generated in the negative electrode can immediately after adding several tens of zinc
The gas generation test and the actual
It was evaluated by making a battery and examining the decrease in capacity.
It was Metal powder such as stainless steel or iron adheres to the negative electrode can.
Or, if there is a defect in the plating film, bubbles will be generated from it.
It Continuous bubbles from relatively large metal powders and defects
Continuous bubbles appearing in the
To be Table 1 shows the copper-tin alloy plating of each example.
Indicates the number of negative electrode cans with open cells against the thickness.
It was The number of negative electrode cans for each gas generation test is 10.
And

[Table 1] The open cells include those that subside after several tens of minutes and those that continue to emerge. The latter can lead to swelling and bursting of the battery. As for the negative electrode can used as an actual battery, from the viewpoint that open cells should not be generated in the gas generation test, when the core material is iron or stainless steel, the core material is 4 μm or more, and the core material is brass, bronze or an intermediate layer plated. When using, a plating thickness of copper-tin alloy of 2 to 3 μm or more is required. Using the copper-tin alloy plated negative electrode cans of Examples 1 to 12, SR626SW size Na was used.
1,000 silver oxide batteries using OH-based electrolyte
Individually made. A silver oxide battery was prepared as described below.
To the center of the concave surface of the positive electrode can 6, 1 part of an electrolytic solution in which ZnO was added to NaOH up to near saturation was dropped. Silver oxide there 2
A positive electrode mixture 5 pelletized by adding graphite in a weight percentage, and then a polyethylene graft polymerized film 2 as a separator 4.
I put one piece of cellophane. On top of that, a gasket 7 coated with an epoxy adhesive and asphalt pitch dissolved in toluene was pressed as a sealant 8. Further, in the concave portion formed by the gasket 7 and the separator 4, the electrolytic solution impregnated material 3 and the negative electrode mixture 2 (0.5 parts of polyacrylic acid-based gelling agent to 100 parts of zinc are added, and the capacity is 1000 ml).
(Mixed for 10 minutes with a V-type mixer having a glass pot) and the rest of the electrolytic solution was added dropwise to the negative electrode mixture 2.
The negative electrode can 1 was inserted so as to fit in the groove of the recess of the gasket 7, and finally the upper part of the positive electrode can 6 was caulked using a shaving press and sealed to produce a silver oxide battery. In Table 2 and Table 3,
The reduction in capacity with respect to the copper-tin alloy plating thickness of each example was shown. The types of zinc used to make silver oxide batteries are
In Table 1, anhydrous silver zinc (containing Al, Bi, In),
In Table 2, zinc iodide (zinc containing 10% by weight of zinc containing Pb) was used. The capacity decrease is represented by%, which is defined as the self-discharge rate, which is the ratio of the initial capacity of the battery minus the capacity after 20 days at 60 ° C., which is said to be equivalent to about one year later, to the initial capacity.

[Table 2]

[Table 3] If the surface is iron, stainless steel, nickel, or if the copper-tin alloy film is thin and part of iron, stainless steel, or nickel is on the surface, there were many defects such as battery swelling and leakage, so storage and capacity The measurement was stopped. In the table,
A horizontal bar is marked. Overall, silver batteries using zinc iodide containing mercury have a lower self-discharge rate. When used as an actual battery, from the viewpoint that there is no problem if the self-discharge rate is 4% or less for practical use, in the battery using the anhydrous zinc-zinc, when iron or stainless steel is used as the core material, 4 μm or more, brass is used. When bronze or a core material plated with an intermediate layer is used, a plating thickness of copper-tin alloy of 2 to 3 μm or more is required. Batteries using zinc iodide require a copper / tin alloy plating thickness of 3 μm or more when iron or stainless steel is used as the core material and 1-2 μm or more when using the core material plated with brass, bronze or an intermediate layer. is there. A silver battery using mercury-free zinc with a relatively thick copper-tin alloy film exhibits a self-discharge rate similar to that of a silver battery using zinc iodide, indicating that mercury as a pollutant can be reduced. . When the intermediate plating layer is formed by barrel plating, the metal powder such as stainless steel and iron adhered during press molding is covered by the intermediate plating layer, so that it is effective even if the copper-tin alloy film is thin. In this embodiment, a plating method, which is a kind of wet process, is mainly used for forming a copper-tin alloy, but another dry process such as vapor deposition, sputtering, ion plating, and CVD is used to form a similar negative electrode can structure. The same silver battery characteristics can be expected even if the embodiment described above is performed. Further, in the present invention, the silver battery has been described, but it goes without saying that the same characteristics can be expected even in an air battery or a manganese battery as long as it is an alkaline battery using zinc powder as the negative electrode active material.

As described in the above examples, by using the copper-tin alloy according to the present invention for the alkaline battery negative electrode can, the characteristics can be improved and the manufacturing cost can be greatly reduced. Furthermore, it has become possible to reduce mercury, which is a pollutant, and energy during manufacturing.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an alkaline battery.

[Name of code]

 DESCRIPTION OF SYMBOLS 1 Negative electrode can 2 Negative electrode mixture 3 Electrolyte impregnating material 4 Separator 5 Positive electrode mixture 6 Positive electrode can 7 Gasket 8 Sealing agent 9 Negative electrode can outside 10 Negative electrode inside 11 Negative electrode can end 12 Negative electrode folded back inside

Claims (7)

[Claims] 1. A coin-type or button-type alkaline battery using zinc or zinc alloy powder as a negative electrode active material,
An alkali characterized by using a negative electrode can which does not include an organic film or an unavoidable oxide film, and whose outermost surface is an alloy containing copper and tin as a main component except at least the end of the negative electrode can and the inside of the folded negative electrode can. battery. 2. The alloy containing copper / tin as a main component is added to at least one metal selected from zinc or nickel to a copper / tin alloy or a copper / tin alloy. 1. The alkaline battery according to 1. 3. The alkaline battery according to claim 1, wherein the alloy containing copper and tin as a main component is a coating layer provided on a metal that is a core material. 4. One or more metal layers are provided for the purpose of improving the adhesion between the coating layer of the alloy containing copper and tin as a main component and the metal that is the core material and reducing defects in the coating. The alkaline battery according to claim 3, wherein the alkaline battery is provided. 5. A single layer provided for the purpose of improving adhesion between the outermost surface of a coating layer of an alloy containing copper and tin as a main component and the metal of the core material and reducing defects in the coating. The alkaline battery according to claim 4, wherein the metal layer is nickel or copper. 6. The alkaline battery according to claim 3, wherein the method of forming the coating layer of the alloy containing copper and tin as a main component is a plating method. 7. The core material metal is stainless steel, iron,
The alkaline battery according to claim 3, which is a metal or an alloy selected from brass.