Battery

Abstract

To prevent an electrolyte from leaking from a battery case.SOLUTION: A battery 1 comprises: a positive electrode can 11 in which an internal space 22 housing a positive electrode 3 and a negative electrode 5 is formed in an internal part; a negative electrode terminal plate 12 blocking an open part 15 formed in the positive electrode can 11; and a sealing gasket 14 sealing a gap formed between the negative electrode terminal plate 12 and the positive electrode can 11. The positive electrode can 11 comprises: a base material; and an internal face side PTFE eutectoid plating layer coating a region that is opposite to the sealing gasket 14 of the base material. The internal face side PTFE eutectoid plating layer contains a layer formed by nickel and a fine particle scattered in the layer. The fine particle is formed by a fluorine material illustrated in a polytetrafluoroethylene PTFE.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The technology of the present disclosure relates to batteries. [Background technology]

[0002] Batteries are known in which the surface of a battery case formed by drawing is plated (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 55-050571 Summary of the Invention [Problem to be solved by the invention]

[0004] Such batteries may be stored for long periods of time as emergency batteries. During storage, the electrolyte may creep up through gaps in the positive electrode can due to cracks in the plating or wrinkles caused by drawing, resulting in leakage of the electrolyte from inside the battery case. Even if leakage is prevented by a sealant, leakage may occur due to the condition of the sealant application or scratches caused by transportation of parts during manufacturing.

[0005] The disclosed technology has been made in consideration of the above-mentioned points, and has an object to provide a battery that prevents electrolyte leakage from the battery case. [Means for solving the problem]

[0006] A battery according to one aspect of the present disclosure includes a battery can having a space formed therein for housing a positive electrode and a negative electrode, a negative electrode terminal plate for closing an opening formed in the battery can, and a gasket for sealing a gap formed between the negative electrode terminal plate and the battery can. The battery can includes a base material, a plating layer for covering an area of ​​the base material facing the gasket, and an alloy layer disposed between the base material and the plating layer;The plating layer has The base material is made of a second metal different from the first metal. The metal layer includes a metal layer and fine particles dispersed in the metal layer, the fine particles being made of a fluorine-based material. The alloy layer is formed from an alloy containing the first metal and the second metal, and is formed so that the concentration of the first metal is greater closer to the base material and the concentration of the second metal is greater closer to the plating layer. Effect of the Invention

[0007] The disclosed battery can prevent leakage of electrolyte from the battery case. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view showing a battery according to an embodiment. [Diagram 2] FIG. 2 is a cross-sectional view showing a part of a positive electrode can of the battery according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a battery according to an embodiment disclosed in the present application will be described with reference to the drawings. Note that the following description does not limit the technology of the present disclosure. In addition, in the following description, the same components are given the same reference numerals, and duplicated descriptions will be omitted.

[0010] The battery 1 of the embodiment is a so-called alkaline battery, and includes a battery case 2, a positive electrode 3, a negative electrode 5, a current collector 6, and a separator 7, as shown in FIG. 1. FIG. 1 is a cross-sectional view showing the battery 1 of the embodiment. An internal space 22 is formed inside the battery case 2. The battery case 2 includes a positive electrode can 11, a negative electrode terminal plate 12, and a sealing gasket 14. The positive electrode can 11 is formed in a bottomed cylindrical shape, and an opening 15 is formed therein. The positive electrode can 11 is formed in a hollow cylindrical shape, and includes a side portion 16 and a bottom portion 17. The side portion 16 is formed so as to follow the side surface of the cylinder. The opening 15 is formed in a portion of the positive electrode can 11 that corresponds to one of the bottom surfaces of the cylinder.

[0011] The side portion 16 is formed with a beading portion 18 and a contact surface 19. The beading portion 18 is formed in the vicinity of the opening 15 of the side portion 16. The beading portion 18 is formed so that the inner diameter of a part of the side portion 16 near the opening 15 is smaller. The contact surface 19 is formed in a region of the inner circumferential surface of the side portion 16 closer to the opening 15 than the beading portion 18. The bottom portion 17 is formed so as to follow the other bottom surface of the cylinder. The bottom portion 17 is formed in a roughly disk shape, and a positive electrode terminal portion 21 is formed in the center. The positive electrode terminal portion 21 is formed so as to protrude from the inside of the positive electrode can 11 toward the outside.

[0012] The negative electrode terminal plate 12 is formed in a generally disk-like shape. The negative electrode terminal plate 12 is disposed in the opening 15 of the positive electrode can 11 so as to seal the opening 15. In the battery case 2, the negative electrode terminal plate 12 seals the opening 15, thereby forming an internal space 22 surrounded by the positive electrode can 11 and the negative electrode terminal plate 12. The sealing gasket 14 is formed of an insulator such as a resin, and is formed in a generally ring-like shape. The sealing gasket 14 surrounds the edge of the negative electrode terminal plate 12, closes the gap formed between the edge of the negative electrode terminal plate 12 and the contact surface 19 of the positive electrode can 11, and seals the internal space 22 from the outside. The sealing gasket 14 further electrically insulates the negative electrode terminal plate 12 from the positive electrode can 11.

[0013] The positive electrode 3 is formed from a positive electrode active material and is formed into a hollow cylindrical shape. The positive electrode active material includes electrolytic manganese dioxide, graphite, a binder, and an aqueous solution of potassium hydroxide. The positive electrode 3 is disposed in the internal space 22 of the battery case 2 and is in close contact with the inner peripheral surface of the side portion 16 of the positive electrode can 11 so that the positive electrode active material is electrically connected to the positive electrode can 11. The negative electrode 5 is formed from a negative electrode active material and is formed into a gel. The negative electrode active material includes zinc alloy powder and an aqueous solution of potassium hydroxide. The negative electrode 5 is disposed inside the positive electrode 3 in the internal space 22 of the battery case 2.

[0014] The current collecting rod 6 is made of a conductor and formed into a rod shape. The current collecting rod 6 is disposed in the internal space 22 and embedded in the negative electrode 5 so as to be electrically connected to the negative electrode active material of the negative electrode 5. The current collecting rod 6 further passes through the center of the sealing gasket 14. One end of the current collecting rod 6 is joined to the negative electrode terminal plate 12 so as to be electrically connected to the negative electrode terminal plate 12.

[0015] The separator 7 is made of polypropylene nonwoven fabric and is formed in a bottomed hollow cylinder shape. That is, the separator 7 has a side portion 25 and a bottom portion 26. The side portion 25 is formed so as to follow the side of the cylinder. The bottom portion 26 is formed so as to follow one bottom surface of the cylinder. The separator 7 is arranged in the internal space 22 of the battery case 2 so that the side portion 25 is arranged between the positive electrode 3 and the negative electrode 5, and the bottom portion 26 is arranged between the negative electrode 5 and the bottom portion 17 of the positive electrode can 11. The separator 7 separates the positive electrode 3 and the negative electrode 5 so that the positive electrode 3 and the negative electrode 5 are not electrically connected, and separates the negative electrode 5 and the positive electrode can 11 so that the negative electrode 5 and the positive electrode can 11 are not electrically connected. The battery 1 further includes an electrolyte. The electrolyte is formed from an aqueous solution containing potassium hydroxide KOH. The electrolyte is permeated into the separator 7.

[0016] FIG. 2 is a cross-sectional view showing the positive electrode can 11. The positive electrode can 11 includes a base material 31, an outer PTFE eutectoid plating layer 32, an inner PTFE eutectoid plating layer 33, an outer alloy layer 34, an inner alloy layer 35, and a nickel plating layer 36. The base material 31 is made of steel and formed into a bent plate shape. The outer PTFE eutectoid plating layer 32 is formed of a dispersion system in which fine particles are dispersed in a plating layer formed of nickel, and is formed into a film shape. The fine particles are formed of polytetrafluoroethylene PTFE. The outer PTFE eutectoid plating layer 32 covers the outer surface of the positive electrode can 11 of the base material 31. The inner PTFE eutectoid plating layer 33 is formed of a dispersion system in which fine particles are dispersed in a plating layer formed of nickel, similar to the outer PTFE eutectoid plating layer 32. The inner PTFE eutectoid plating layer 33 covers the inner surface of the positive electrode can 11 of the base material 31.

[0017] The outer surface side alloy layer 34 is formed of an alloy of iron and nickel, and is formed in a film shape. The outer surface side alloy layer 34 is disposed between the base material 31 and the outer surface side PTFE eutectoid plating layer 32, one surface of the outer surface side alloy layer 34 is bonded to the base material 31, and the other surface of the outer surface side alloy layer 34 is bonded to the outer surface side PTFE eutectoid plating layer 32. In this case, in detail, the outer surface side alloy layer 34 has a concentration gradient such that the concentration of iron is higher closer to the base material 31, and the concentration of nickel is higher closer to the outer surface side PTFE eutectoid plating layer 32. Since the concentration gradient is formed in the outer surface side alloy layer 34, the outer surface side alloy layer 34 can be firmly bonded to the base material 31 and can be firmly bonded to the outer surface side PTFE eutectoid plating layer 32. Since the concentration gradient is formed in the outer surface side alloy layer 34, the battery 1 can prevent the outer surface side PTFE eutectoid plating layer 32 from peeling off from the base material 31.

[0018] The inner alloy layer 35 is formed of an alloy of iron and nickel, and is formed in a film shape. The inner alloy layer 35 is disposed between the base material 31 and the inner PTFE eutectoid plating layer 33, and one surface of the inner alloy layer 35 is bonded to the base material 31. The nickel plating layer 36 is formed of nickel, and is formed in a film shape. The nickel plating layer 36 is disposed between the inner alloy layer 35 and the inner PTFE eutectoid plating layer 33, and one surface of the inner alloy layer 35 is bonded to the inner PTFE eutectoid plating layer 33, and the other surface of the inner alloy layer 36 is bonded to the inner PTFE eutectoid plating layer 33. In this case, in detail, the inner alloy layer 35 has a concentration gradient such that the concentration of iron is higher closer to the base material 31, and the concentration of nickel is higher closer to the nickel plating layer 36. The inner alloy layer 35 can be firmly bonded to the base material 31 and the nickel plating layer 36 due to the concentration gradient formed. In addition, since the inner surface PTFE eutectoid plating layer 33 and the nickel plating layer 36 are formed of nickel, the inner surface PTFE eutectoid plating layer 33 is firmly bonded to the nickel plating layer 36. Since the inner surface PTFE eutectoid plating layer 33 and the base material 31 are bonded via the nickel plating layer 36 and the inner surface alloy layer 35, the inner surface PTFE eutectoid plating layer 33 can be prevented from peeling off from the base material 31.

[0019] The positive electrode can 11 has a water-repellent surface due to being coated with the outer PTFE eutectoid plating layer 32 and the inner PTFE eutectoid plating layer 33. Since the contact surface 19 of the positive electrode can 11 of the battery 1 has water-repellency, the battery 1 can prevent liquid disposed in the internal space 22 from penetrating between the positive electrode can 11 and the sealing gasket 14 due to capillary action. Since the battery 1 can prevent the liquid disposed in the internal space 22 from penetrating between the positive electrode can 11 and the sealing gasket 14, the battery 1 can prevent the liquid disposed in the internal space 22 from leaking to the outside.

[0020] The negative electrode terminal plate 12, like the positive electrode can 11, comprises a base material and a PTFE eutectoid plating layer. Like the base material 31, the base material is made of steel. Like the outer surface PTFE eutectoid plating layer 32 and the inner surface PTFE eutectoid plating layer 33, the PTFE eutectoid plating layer is formed of a dispersion system in which fine particles are dispersed in a continuous phase made of nickel, and is formed in the form of a film. The fine particles are made of polytetrafluoroethylene (PTFE). The base material is covered with the PTFE eutectoid plating layer.

[0021] The negative electrode terminal plate 12 has a water-repellent surface due to being covered with a PTFE eutectoid plating layer. The water-repellent edge of the negative electrode terminal plate 12 of the battery 1 inhibits the intrusion of moisture in the outside air through the gas vent hole of the negative electrode terminal plate 12, and can prevent moisture from penetrating the sealing gasket 14 and entering the inside of the battery 1. When moisture enters the internal space 22 of the battery 1, the internal pressure increases, causing the valve of the sealing gasket 14 to operate, preventing the electrolyte from leaking to the outside.

[0022] [Manufacturing method of battery 1] The manufacturing method for manufacturing the battery 1 includes the steps of preparing the positive electrode can 11, preparing the negative electrode terminal plate 12, and assembling the battery 1. The surface of a steel sheet that is the material for the positive electrode can 11 and the negative electrode terminal plate 12 is nickel-plated, and then continuous annealing is performed. By this annealing, an iron-nickel alloy is formed, and an outer surface side alloy layer 34, an inner surface side alloy layer 35, and a nickel plating layer 36 are formed. Then, the steel sheet is immersed in a plating solution in which fine particles formed from polytetrafluoroethylene (PTFE) are dispersed, and eutectoid plating is performed to prepare a plated steel sheet. The plated steel sheet is deep-drawn to prepare the positive electrode can 11. On both sides of the positive electrode can 11, an outer surface side PTFE eutectoid plating layer 32 and an inner surface side PTFE eutectoid plating layer 33 are formed by this eutectoid plating.

[0023] In producing the negative electrode terminal plate 12, the above-mentioned plated steel sheet is pressed to produce the negative electrode terminal plate 12. A PTFE eutectoid plating layer is formed on the surface of the negative electrode terminal plate 12 by eutectoid plating.

[0024] In assembling the battery 1, a positive electrode 3 is produced by forming a positive electrode active material prepared using electrolytic manganese dioxide, graphite, a binder, and an aqueous potassium hydroxide solution into a ring shape. The positive electrode 3 is fitted into the positive electrode can 11 so that the outer peripheral surface of the positive electrode 3 contacts the inner peripheral surface of the positive electrode can 11. After the positive electrode 3 is fitted into the positive electrode can 11, the positive electrode can 11 is processed so that a beading portion 18 is formed. After the beading portion 18 is formed in the positive electrode can 11, the separator 7 is inserted inside the positive electrode 3. After the separator 7 is inserted inside the positive electrode 3, the separator 7 is impregnated with an electrolyte.

[0025] In the assembly of the battery 1, a gelled negative electrode 5 is further prepared using zinc alloy powder and an aqueous potassium hydroxide solution. The negative electrode 5 is injected into the separator 7 after the separator 7 is saturated with the electrolyte. After the negative electrode 5 is injected, the current collector 6, the negative electrode terminal plate 12, and the sealing gasket 14 are attached to the positive electrode can 11 so that the current collector 6 joined to the negative electrode terminal plate 12 is embedded in the negative electrode 5 and the negative electrode terminal plate 12 and the sealing gasket 14 close the opening 15. After the current collector 6, the negative electrode terminal plate 12, and the sealing gasket 14 are attached to the positive electrode can 11, a portion of the positive electrode can 11 near the opening 15 is crimped so that a gap formed between the edge of the negative electrode terminal plate 12 and the contact surface 19 of the positive electrode can 11 is sealed by the sealing gasket 14. When the positive electrode can 11 is crimped, the sealing gasket 14 is deformed, the current collector rod 6, the negative electrode terminal plate 12, and the sealing gasket 14 are fixed to the positive electrode can 11, the internal space 22 is sealed from the outside, and the battery 1 is completed.

[0026] In a production line in which battery 1 is manufactured, positive electrode can 11 is conveyed by a conveying device along a conveying path, sliding against other positive electrode cans and guide surfaces that form the conveying path. Since the outer surface of positive electrode can 11 is coated with outer-side PTFE eutectoid plating layer 32, battery 1 has good sliding properties and is prevented from getting caught on other positive electrode cans 11 or the guide surfaces of the conveying path, allowing it to be conveyed appropriately along the conveying path.

[0027] The positive electrode terminal portion 21 and the negative electrode terminal plate 12 come into contact with two device-side terminals provided on the device when the battery 1 is appropriately mounted on the device. The battery 1 supplies DC power to the device when the positive electrode terminal portion 21 and the negative electrode terminal plate 12 come into contact with the two device-side terminals of the device. The portion of the positive electrode terminal portion 21 of the positive electrode can 11 that comes into contact with the device-side terminal is formed from the outer PTFE eutectoid plating layer 32, that is, the region of the base material 31 that faces the device-side terminal is covered with the outer PTFE eutectoid plating layer 32. Since the outer surface of the positive electrode can 11 of the battery 1 is covered with the outer PTFE eutectoid plating layer 32, an oxide film is less likely to be generated in comparison with a hard plating layer, and electrical contact with the device-side terminal is good.

[0028] The portion of the negative electrode terminal plate 12 that contacts the device side terminal is formed from a PTFE eutectoid plating layer, i.e., the region of the base material of the negative electrode terminal plate 12 that faces the device side terminal is covered with a PTFE eutectoid plating layer. Since the outer surface of the negative electrode terminal plate 12 of the battery 1 is covered with a PTFE eutectoid plating layer, an oxide film is less likely to be generated compared to a hard plating layer, and electrical contact with the device side terminal is good. Therefore, the battery 1 can improve the discharge performance of supplying DC power to the device in which the battery 1 is mounted.

[0029] [Evaluation test of battery 1] In order to confirm the effect of the battery 1 of the embodiment, a plurality of battery samples having different PTFE co-deposition amounts are manufactured, and a plurality of evaluation tests are performed. The PTFE co-deposition amount indicates the concentration of fine particles in the outer PTFE co-deposition plating layer 32 and the inner PTFE co-deposition plating layer 33 of the positive electrode can 11, and indicates a value obtained by dividing the volume of the fine particles by the volume of the outer PTFE co-deposition plating layer 32 and the inner PTFE co-deposition plating layer 33. The plurality of battery samples are manufactured similarly to each other, except that the PTFE co-deposition amounts are different from each other. The plurality of battery samples include a comparative example battery, a battery of Example 1, a battery of Example 2, a battery of Example 3, a battery of Example 4, and a battery of Example 5.

[0030] The PTFE co-deposited amount in the battery of the comparative example is 0 vol.%. The PTFE co-deposited amount in the battery of Example 1 is 1 vol.%. The PTFE co-deposited amount in the battery of Example 2 is 5 vol.%. The PTFE co-deposited amount in the battery of Example 3 is 10 vol.%. The PTFE co-deposited amount in the battery of Example 4 is 15 vol.%. The PTFE co-deposited amount in the battery of Example 5 is 20 vol.%.

[0031] The multiple evaluation tests for confirming the effects of the battery 1 include a water repellency test, a leakage test, a slipperiness test, and a contact resistance measurement. In the water repellency test, multiple contact angles corresponding to multiple battery samples are measured. One of the multiple contact angles corresponding to a certain battery sample indicates the angle formed between the liquid surface of a water droplet and the surface of the positive electrode can 11 at the point where the free surface of the water droplet contacts the surface of the positive electrode can 11 when a predetermined amount of water droplet is placed on the surface of the positive electrode can 11 of that battery sample. A larger contact angle indicates a higher water repellency of the surface of the positive electrode can 11.

[0032] Table 1 shows the results of the water repellency test. [Table 1] The contact angle corresponding to the battery of the comparative example is 48 degrees. The contact angle corresponding to the battery of Example 1 is 77 degrees. The contact angle corresponding to the battery of Example 2 is 80 degrees. The contact angle corresponding to the battery of Example 3 is 97 degrees. The contact angle corresponding to the battery of Example 4 is 99 degrees. The contact angle corresponding to the battery of Example 5 is 100 degrees. The results of the water repellency test show that the larger the amount of PTFE co-deposition, the larger the contact angle is, and the contact angles corresponding to the batteries of Examples 1 to 5 are larger than the contact angle corresponding to the battery of the comparative example.

[0033] In the leakage test, multiple creep leakage occurrence rates corresponding to multiple battery samples are measured. One creep leakage occurrence rate corresponding to a certain battery sample among the multiple creep leakage occurrence rates indicates the rate at which leakage occurs in the battery sample when the battery sample is stored in an atmosphere of 60°C and 90% humidity for 150 days. Leakage indicates leakage of electrolyte from the internal space 22 to the outside through the gap between the positive electrode can 11 and the negative electrode terminal plate 12 of the battery sample. The smaller the creep leakage occurrence rate, the better the leakage resistance of the battery sample.

[0034] Table 2 shows the results of the leakage test. [Table 2] The creep leakage occurrence rate for the battery of the comparative example is 20%. The creep leakage occurrence rate for the battery of Example 1 is 0%. The creep leakage occurrence rate for the battery of Example 2 is 0%. The creep leakage occurrence rate for the battery of Example 3 is 0%. The creep leakage occurrence rate for the battery of Example 4 is 0%. The creep leakage occurrence rate for the battery of Example 5 is 0%. The results of the leakage test show that leakage occurs when the PTFE co-deposition amount is 0 vol.%, but no leakage occurs when the PTFE co-deposition amount is equal to or greater than 1 vol.%.

[0035] In the slipperiness test, a plurality of kinetic friction coefficients and a plurality of static friction coefficients corresponding to a plurality of battery samples are measured using an autograph manufactured by Shimadzu Corporation in accordance with the JIS standard JIS K7125. One of the plurality of kinetic friction coefficients corresponding to a certain battery sample indicates the kinetic friction coefficient of the surface of the positive electrode can 11 of the battery sample after the battery sample is stored in an atmosphere of 60°C and 90% humidity for 150 days. One of the plurality of static friction coefficients corresponding to a certain battery sample indicates the static friction coefficient of the surface of the positive electrode can 11 of the battery sample after the battery sample is stored in an atmosphere of 60°C and 90% humidity for 150 days. The smaller the kinetic friction coefficient and static friction coefficient, the better the slipperiness of the surface of the positive electrode can 11 of the battery sample.

[0036] Table 3 shows the results of the slipperiness test. [Table 3] The kinetic friction coefficient corresponding to the battery of the comparative example is 0.12. The kinetic friction coefficient corresponding to the battery of the example 1 is 0.11. The kinetic friction coefficient corresponding to the battery of the example 2 is 0.10. The kinetic friction coefficient corresponding to the battery of the example 3 is 0.09. The kinetic friction coefficient corresponding to the battery of the example 4 is 0.08. The kinetic friction coefficient corresponding to the battery of the example 5 is 0.06. The static friction coefficient corresponding to the battery of the comparative example is 0.15. The static friction coefficient corresponding to the battery of the example 1 is 0.14. The static friction coefficient corresponding to the battery of the example 2 is 0.13. The static friction coefficient corresponding to the battery of the example 3 is 0.12. The static friction coefficient corresponding to the battery of the example 4 is 0.11. The static friction coefficient corresponding to the battery of the example 5 is 0.10. The results of the slipperiness test show that the larger the PTFE co-deposition amount is, the smaller the kinetic friction coefficient is, and the larger the PTFE co-deposition amount is, the smaller the static friction coefficient is.

[0037] In the contact resistance measurement, a plurality of contact resistance values ​​corresponding to a plurality of battery samples are measured. One of the plurality of contact resistance values ​​corresponding to a certain battery sample indicates the contact resistance of the surface of the positive electrode can 11 of the battery sample after the battery sample is stored in an atmosphere of 60°C and 90% humidity for 7 days. A smaller contact resistance value indicates better electrical contact between the battery sample and the device, and a smaller value indicates better discharge performance of the battery sample.

[0038] Table 4 shows the results of the contact resistance measurements. [Table 4] The contact resistance value corresponding to the battery of the comparative example is 144 mΩ. The contact resistance value corresponding to the battery of Example 1 is 31 mΩ. The contact resistance value corresponding to the battery of Example 2 is 28 mΩ. The contact resistance value corresponding to the battery of Example 3 is 28 mΩ. The contact resistance value corresponding to the battery of Example 4 is 27 mΩ. The contact resistance value corresponding to the battery of Example 5 is 27 mΩ. The results of the contact resistance measurements show that the greater the amount of PTFE co-deposition, the smaller the contact resistance value.

[0039] Table 5 shows the results of multiple evaluation tests. [Table 5] The results of the multiple evaluation tests show that the water repellency of the surface of the positive electrode can 11 of the battery having a PTFE co-deposition amount equal to or greater than 1 vol.% is good. That is, the results of the multiple evaluation tests show that the water repellency of the surface of the positive electrode can 11 of the battery of Example 1 to Example 5 is better than the water repellency of the surface of the positive electrode can 11 of the battery of the comparative example. The results of the multiple evaluation tests further show that the water repellency of the surface of the positive electrode can 11 of the battery of Example 3 to Example 5 is even better than the water repellency of the surface of the positive electrode can 11 of the battery of Example 1 to Example 2. That is, the results of the multiple evaluation tests show that the water repellency of the surface of the positive electrode can 11 of the battery having a PTFE co-deposition amount equal to or greater than 10 vol.% is better than the water repellency of the surface of the positive electrode can 11 of the battery having a PTFE co-deposition amount less than 10 vol.%.

[0040] The results of multiple evaluation tests show that the leakage resistance of batteries having a PTFE co-deposition amount equal to or greater than 1 vol.% is good, and that the leakage resistance of the batteries of Examples 1 to 5 is better than that of the comparative battery. The results of multiple evaluation tests further show that the batteries having good water repellency on the surface of positive electrode can 11 also have good leakage resistance.

[0041] The results of the evaluation tests show that the surface slipperiness of the positive electrode can 11 of the battery having a PTFE co-deposition amount equal to or greater than 1 vol.% is good. That is, the results of the evaluation tests show that the surface slipperiness of the positive electrode can 11 of the battery of the comparative example is better than that of the positive electrode can 11 of the battery of the comparative example. Therefore, the results of the evaluation tests show that the positive electrode can 11 of the battery of the comparative example can be more appropriately transported along the transport path than the positive electrode can 11 of the battery of the comparative example. The results of the evaluation tests further show that the surface slipperiness of the positive electrode can 11 of the battery of the comparative example is even better than that of the positive electrode can 11 of the battery of the comparative example. That is, the results of the evaluation tests show that the surface slipperiness of the positive electrode can 11 of the battery of the comparative example is better than that of the positive electrode can 11 of the battery of the comparative example.

[0042] The results of the evaluation tests show that the batteries having a PTFE co-deposition amount equal to or greater than 1 vol.% have good electrical contact with the equipment and good discharge performance of the battery samples. That is, the results of the evaluation tests show that the electrical contact with the equipment of the batteries of Examples 1 to 5 is better than the electrical contact with the equipment of the battery of the comparative example. Therefore, the results of the evaluation tests show that the discharge performance of the positive electrode can 11 of the batteries of Examples 1 to 5 is better than that of the positive electrode can 11 of the battery of the comparative example.

[0043] [Effects of Battery 1 of the Embodiment] The battery 1 of the embodiment includes a positive electrode 3, a negative electrode 5, a positive electrode can 11, a negative electrode terminal plate 12, and a sealing gasket 14. The positive electrode can 11 has an internal space 22 formed therein in which the positive electrode 3 and the negative electrode 5 are stored. The negative electrode terminal plate 12 closes an opening 15 formed in the positive electrode can 11. The sealing gasket 14 seals a gap formed between the negative electrode terminal plate 12 and the positive electrode can 11. The positive electrode can 11 includes a base material 31 and an inner surface PTFE eutectoid plating layer 33 that covers an area of ​​the base material 31 facing the sealing gasket 14. The inner surface PTFE eutectoid plating layer 33 includes a layer formed of nickel and fine particles dispersed in the layer. The fine particles are formed of polytetrafluoroethylene PTFE.

[0044] At this time, in battery 1, contact surface 19 of positive electrode can 11 facing sealing gasket 14 has water repellency, and can prevent liquid disposed in internal space 22 from penetrating between positive electrode can 11 and sealing gasket 14 due to capillary action. By preventing liquid disposed in internal space 22 from penetrating between positive electrode can 11 and sealing gasket 14, battery 1 can prevent liquid disposed in internal space 22 from leaking to the outside.

[0045] Furthermore, the outer PTFE eutectoid plating layer 32 of the battery 1 of the embodiment further covers the outer surface of the base material 31 behind the inner surface that faces the internal space 22. In this case, the outer surface of the positive electrode can 11 of the battery 1 has slippery properties, which prevents the battery 1 from getting caught on other batteries or the guide surface of the transport path when the battery 1 is transported along the transport path, thereby improving productivity.

[0046] Furthermore, the outer PTFE eutectoid plating layer 32 of the battery 1 of the embodiment further covers the positive electrode terminal portion 21 of the base material 31 that faces the equipment side terminal that is in electrical contact with the positive electrode can 11. In this case, since an oxide film is unlikely to form on the positive electrode terminal portion 21 of the positive electrode can 11, the battery 1 can reduce the contact resistance between the positive electrode terminal portion 21 and the equipment side terminal, and can improve the discharge performance of supplying DC power to the equipment in which the battery 1 is mounted.

[0047] Furthermore, the PTFE eutectoid plating layer of the negative electrode terminal plate 12 of the battery 1 of the embodiment further covers a terminal portion of the base material that faces the device side terminal that is in electrical contact with the negative electrode terminal plate 12. In this case, since an oxide film is unlikely to form on the negative electrode terminal plate 12 of the battery 1, the contact resistance between the negative electrode terminal plate 12 and the device side terminal can be reduced, and the discharge performance of supplying DC power to the device in which the battery 1 is mounted can be improved.

[0048] Incidentally, the outer surface side PTFE eutectoid plating layer 32 and the inner surface side PTFE eutectoid plating layer 33 are formed so that the PTFE eutectoid amounts are equal to each other, but they may be formed so that the PTFE eutectoid amounts are different from each other. Even in such a case, the battery 1 can prevent leakage, improve productivity, and improve discharge performance.

[0049] Incidentally, the fine particles dispersed in the outer PTFE eutectoid plating layer 32 and the inner PTFE eutectoid plating layer 33 are formed of PTFE, but may be formed of other fluorine-based materials other than PTFE. Examples of the fluorine-based materials include tetrafluoroethylene-hexafluoropropylene copolymer FEP, ethylene-tetrafluoroethylene copolymer ETFE, polychlorotrifluoroethylene PCTFE, polyvinylidene fluoride PVDF, and polyvinyl fluoride PVF. Examples of the fluorine-based materials include copolymers PFA of tetrafluoroethylene C2F4 and perfluoroether CF2F3ORf. Here, Rf is a perfluoro group, and an example of the perfluoro group is trifluoromethyl CF3. Even if the fine particles are formed of such a fluorine-based material, the battery 1 can prevent leakage, improve productivity, and improve discharge performance.

[0050] Although the above-described battery 1 is formed as an alkaline battery, it may be formed as a battery other than an alkaline battery. Even in such a case, the battery 1 can prevent leakage, improve productivity, and improve discharge performance.

[0051] Although the embodiments have been described above, the embodiments are not limited to the above. The above-described components include those that can be easily imagined by a person skilled in the art, those that are substantially the same, and those that are within the so-called equivalent range. Furthermore, the above-described components can be appropriately combined. Furthermore, at least one of various omissions, substitutions, and modifications of the components can be made without departing from the gist of the embodiments. [Explanation of symbols]

[0052] 1:Battery 3: Positive electrode 5: Negative electrode 11: Positive electrode can 12:Negative terminal plate 14: Sealing gasket 15: Opening 16: Side part 17: Bottom part 19: Contact surface 21:Positive terminal part 22: Interior space 31: Base material 32: Outer PTFE eutectoid plating layer 33: Inner PTFE eutectoid plating layer 34: Outer alloy layer 35: Inner alloy layer

Claims

1. a battery can having a space formed therein in which a positive electrode and a negative electrode are housed; a plate for closing an opening formed in the battery can; a gasket that seals a gap formed between the plate and the battery can, The battery can is A base material; a plating layer covering an area of ​​the base material facing the gasket; An alloy layer is disposed between the base material and the plating layer, The plating layer is a layer formed of a second metal different from a first metal from which the base material is formed; and fine particles dispersed in the layer. the fine particles are formed from a fluorine-based material, The alloy layer is formed from an alloy containing the first metal and the second metal, and is formed so that the concentration of the first metal is greater closer to the base material and the concentration of the second metal is greater closer to the plating layer. battery.

2. The plating layer further covers an outer surface of the base material on the back side of an inner surface facing the space.

10. The battery of claim 1.

3. The plating layer further covers a terminal portion of the base material that faces an equipment side terminal that is in electrical contact with the battery can. The battery according to claim 1 or 2.

4. The plate is With other base materials, Another plating layer covering an area of ​​the other base material facing the gasket; Another alloy layer is disposed between the other base material and the other plating layer, The other plating layer is another layer formed of a fourth metal different from the third metal of which the other matrix is ​​formed; and other fine particles dispersed in the other layer, the other fine particles are formed from a fluorine-based material, The other alloy layer is formed from an alloy containing the third metal and the fourth metal, and is formed so that the concentration of the third metal increases toward the other base material and the concentration of the fourth metal increases toward the other plating layer. The battery according to any one of claims 1 to 3.

5. The other plating layer further covers a terminal portion of the other base material that faces an equipment side terminal that is in electrical contact with the plate.

5. The battery of claim 4.

6. a battery can having a space formed therein in which a positive electrode and a negative electrode are housed; a plate for closing an opening formed in the battery can; a gasket that seals a gap formed between the plate and the battery can, The plate is A base material; a plating layer covering an area of ​​the base material facing the gasket; An alloy layer is disposed between the base material and the plating layer, The plating layer is a layer formed of a second metal different from a first metal from which the base material is formed; and fine particles dispersed in the layer. the fine particles are formed from a fluorine-based material, The alloy layer is formed from an alloy containing the first metal and the second metal, and is formed so that the concentration of the first metal is greater closer to the base material and the concentration of the second metal is greater closer to the plating layer. battery.

7. a battery can having a space formed therein in which a positive electrode and a negative electrode are housed; a plate for closing an opening formed in the battery can; a gasket that seals a gap formed between the plate and the battery can, The battery can is A base material; a plating layer covering an outer surface of the base material on the back side of an inner surface facing the space; An alloy layer is disposed between the base material and the plating layer, The plating layer is a layer formed of a second metal different from a first metal from which the base material is formed; and fine particles dispersed in the layer. the fine particles are formed from a fluorine-based material, The alloy layer is formed from an alloy containing the first metal and the second metal, and is formed so that the concentration of the first metal is greater closer to the base material and the concentration of the second metal is greater closer to the plating layer. battery.

8. a battery can having a space formed therein in which a positive electrode and a negative electrode are housed; a plate for closing an opening formed in the battery can; a gasket that seals a gap formed between the plate and the battery can, The battery can is A base material; a plating layer that covers a terminal portion of the base material that faces an apparatus side terminal that electrically contacts the battery can; An alloy layer is disposed between the base material and the plating layer, The plating layer is a layer formed of a second metal different from a first metal from which the base material is formed; and fine particles dispersed in the layer. the fine particles are formed from a fluorine-based material, The alloy layer is formed from an alloy containing the first metal and the second metal, and is formed so that the concentration of the first metal is greater closer to the base material and the concentration of the second metal is greater closer to the plating layer. battery.

9. a battery can having a space formed therein in which a positive electrode and a negative electrode are housed; a plate for closing an opening formed in the battery can; a gasket that seals a gap formed between the plate and the battery can, The plate is A base material; a plating layer covering an area of ​​the base material facing an equipment side terminal that is in electrical contact with the plate; An alloy layer is disposed between the base material and the plating layer, The plating layer is a layer formed of a second metal different from a first metal from which the base material is formed; and fine particles dispersed in the layer. the fine particles are formed from a fluorine-based material, The alloy layer is formed from an alloy containing the first metal and the second metal, and is formed so that the concentration of the first metal is greater closer to the base material and the concentration of the second metal is greater closer to the plating layer. battery.

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