CN103258976A - Mercury-free and lead-free button cell - Google Patents

Abstract

The invention discloses a mercury-free and lead-free button battery, which comprises a negative electrode cover, a positive electrode material, a sealing ring, a positive electrode shell, a negative electrode material and a diaphragm; the positive electrode shell is buckled and connected with the negative electrode cover; the sealing ring is clamped between the positive electrode shell and the negative electrode cover so as to separate the positive electrode shell and the negative electrode cover from each other; the anode material is arranged at the inner bottom of the anode shell, the diaphragm is arranged above the anode material, and the cathode material is arranged between the cathode cover and the diaphragm; a conductive film which is used for isolating the negative electrode material from the negative electrode cover and connecting the negative electrode material with the negative electrode cover in a conduction manner is arranged between the negative electrode cover and the negative electrode material; by this, through be provided with the conducting film between negative pole lid and negative pole material to guarantee that negative pole material and negative pole lid keep keeping apart, effectively avoided because negative pole material and negative pole lid contact and make the product phenomenon that gas expansion, weeping or even explosion appear, stopped the potential safety hazard, the security of product use is better.

Description

Mercury-free and lead-free button cell batteries

technical field

The invention relates to the technical field of chemical power supply and battery manufacturing, in particular to a mercury-free and lead-free button battery, including an alkaline zinc-manganese button battery and a silver oxide button battery.

Background technique

Please refer to shown in Fig. 1, it has shown the specific structure of existing button battery, comprises negative electrode cover 10 ', positive electrode material 20 ', sealing ring 30 ', negative electrode material 40 ', positive electrode shell 50 ' and for The diaphragm 60' that isolates the positive electrode material 20' and the negative electrode material 40'; the positive electrode case 50' is fastened and connected with the negative electrode cover 10'; the sealing ring 30' is sandwiched between the positive electrode case 50' and the negative electrode cover 10' to The positive electrode case 50' and the negative electrode cover 10' are separated from each other; the positive electrode material 20' is arranged on the inner bottom of the positive electrode case 50', the diaphragm 60' is arranged on the top of the positive electrode material 20', and the negative electrode material 40' is installed on the Between the negative electrode cover 10' and the separator 60', the negative electrode material 40' is mercury-free and lead-free zinc paste; usually, the negative electrode cover 10' is made of iron sheet or other iron-based metal sheets, and the negative electrode material 40 The hydrogen evolution reaction easily takes place in contact with metals with low hydrogen evolution overpotential such as iron. Therefore, in order to prevent the negative electrode material 40 ' from contacting the base metal of the negative electrode cover 10 ' and the hydrogen evolution reaction occurs, the existing mercury-free and lead-free button cells need A layer of metal with high hydrogen evolution overpotential is plated on the surface of the negative electrode cover 10', and the negative electrode cover 10' is usually indium-plated or tin-plated so that the negative electrode material 40' is separated from the base metal of the negative electrode cover 10' to avoid The negative electrode material 40' is in contact with the base metal of the negative electrode cover 10' to undergo a hydrogen evolution reaction.

Although the above-mentioned mercury-free and lead-free button battery can separate the negative electrode material and the base metal of the negative electrode cover from each other to a certain extent by performing indium plating or tin plating on the negative electrode cover, it has been found in practical applications that There are still many deficiencies in its own structure and performance, causing the existing mercury-free and lead-free button batteries to fail to achieve the best use effect and work performance in practical applications. Now its shortcomings are summarized as follows:

First of all, due to its own structural reasons, the above-mentioned negative electrode cover is prone to electroplating such as uneven plating, non-dense plating, pores, easy scratches, easy fall off, easy oxidation, and long whiskers after plating during the indium plating or tin plating process. Bad problem: due to the poor electroplating of the negative electrode cover, the negative electrode material is easy to contact with the base metal of the negative electrode cover, such as iron and other metals with low hydrogen evolution overpotential, and a hydrogen evolution reaction occurs. The hydrogen gas generated by the hydrogen evolution reaction makes the button battery swell, leak or even explode. .

Secondly, in the indium or tin plating process of the above-mentioned negative electrode cover, it is necessary to coat the negative electrode cover with a layer of indium or a layer of tin as a whole. The layer is etched away with chemical potions, and only the indium layer or tin layer on the inner surface of the negative electrode cover is retained. In this production process, a large amount of industrial sewage containing heavy metal ions such as indium or chromium or copper needs to be discharged, which is harmful to the environment. It causes pollution and is not environmentally friendly; at the same time, because indium is a rare metal and is expensive, the production cost of the enterprise is high, and the etched indium will cause waste of resources and increase the burden on the enterprise.

Third, the above-mentioned mercury-free and lead-free button batteries still have a serious disadvantage in terms of performance, that is, during use, especially after continuous discharge under heavy load, severe gas swelling or even explosion will often occur. Phenomenon, security risks can not be ignored.

In a word, the prior art has the above-mentioned serious shortcomings that are difficult to overcome. It is necessary to find a new technical solution to solve these problems, so that the mercury-free process of alkaline button batteries is safe and environmentally friendly.

Contents of the invention

In view of this, the present invention aims at the shortcomings of the prior art, and its main purpose is to provide a mercury-free and lead-free button battery, which can effectively solve the problem of poor electroplating of the negative cover of the existing mercury-free and lead-free button battery. Or there is a problem of greater safety hazard due to continuous discharge of heavy loads.

Another object of the present invention is to provide a mercury-free and lead-free button battery, which can effectively solve the problem that the existing mercury-free and lead-free button battery needs to be indium-plated or tin-plated on the negative electrode cover, which is not environmentally friendly and The problem of increasing the production cost of enterprises.

To achieve the above object, the present invention adopts the following technical solutions:

A mercury-free and lead-free button cell, comprising a negative cover, a positive material, a sealing ring, a positive case, a negative material connected to the negative cover, and a separator for isolating the positive material and the negative material; The positive electrode case and the negative electrode cover are buckled and connected; the sealing ring is interposed between the positive electrode case and the negative electrode cover to isolate the positive electrode case and the negative electrode cover from each other; the positive electrode material is arranged on the inner bottom of the positive electrode case, and the diaphragm is arranged on the Above the positive electrode material, the negative electrode material is installed between the negative electrode cover and the separator; between the negative electrode cover and the negative electrode material, there is a device for isolating the negative electrode material and the negative electrode cover from each other and simultaneously connecting the negative electrode material and the negative electrode cover. An isolation unit, the isolation unit is a conductive film, the conductive film is arranged on the inner surface of the negative electrode cover and covers the bottom or top of the outer ring body of the negative electrode cover or between the bottom and the top, and the conductive film connects the negative electrode material and the negative electrode cover to each other The isolation is separated, and the conductive film is conductively connected between the negative electrode material and the negative electrode cover.

As a preferred solution, the conductive film is a strong alkali-resistant conductive material that is hydrogen-permeable but not electrolyte-permeable, and the material is a graphite-based composite material or a carbon black-based composite material or a hydrogen-permeable alloy material or a hydrogen-permeable alloy composite material. Material.

As a preferred solution, an exhaust hole is provided on the negative electrode cover, or a capillary channel for exhaust gas is provided between the outer ring body of the negative electrode cover and the isolation unit.

As a preferred solution, the negative electrode cover is punched from iron sheet or other iron-based metal sheets, and the surface of the negative electrode cover is at least plated with a layer of nickel, or the negative electrode cover is directly made of pre-plated metal sheet or laminated metal sheet punched.

As a preferred solution, the pre-plated metal sheet is a nickel-plated steel strip or a steel strip that is nickel-plated on one side and copper-plated on the other side.

As a preferred version, the laminated metal sheet is nickel/stainless steel/nickel, or nickel/iron/nickel, or nickel/stainless steel/copper, or a three-layer composite steel strip of nickel/iron/copper, or nickel/stainless steel Two-layer composite steel belt.

As a preferred solution, the negative electrode material is mercury-free and lead-free zinc paste.

Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, it can be known from the above technical solutions:

1. By installing an isolation unit between the negative electrode cover and the negative electrode material, the conductive film is used to separate the negative electrode cover from the negative electrode material to prevent the hydrogen evolution reaction from occurring due to the contact between the negative electrode material and the negative electrode cover, thereby replacing the existing one. Or the form of tin plating to separate the negative electrode material from the base metal of the negative electrode cover. In this way, on the one hand, it is beneficial to ensure that the negative electrode material and the negative electrode cover are kept separated, effectively avoiding the contact between the negative electrode material and the negative electrode cover, which will cause the product to appear inflated, leak or even explode, and eliminate potential safety hazards. The safety of product use Better; on the other hand, the present invention does not need to use indium plating or tin plating in the production of the negative electrode cover, effectively avoiding the need to discharge or containing indium or chromium or containing The environmental pollution caused by the industrial sewage of copper and other heavy metal ions is beneficial to environmental protection, and it also reduces the production cost of enterprises and reduces the burden on enterprises.

2. By providing a vent hole on the negative electrode cover or a capillary channel for exhausting between the outer ring body of the negative electrode cover and the isolation unit, hydrogen evolution occurs inside the button battery by using the vent hole or these capillary channels. The hydrogen gas produced during the reaction is discharged to prevent the gas from accumulating inside the button battery, causing the button battery to swell, leak or even explode, and further improve the safety of the product.

In order to more clearly illustrate the structural features and functions of the present invention, the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

Description of drawings

Fig. 1 is the sectional view of existing button battery;

Fig. 2 is the sectional view of the first preferred embodiment of the present invention;

Fig. 3 is the sectional view of the second preferred embodiment of the present invention;

Fig. 4 is the sectional view of the third preferred embodiment of the present invention;

Fig. 5 is the sectional view of the 4th preferred embodiment of the present invention;

Fig. 6 is the sectional view of the fifth preferred embodiment of the present invention;

Fig. 7 is the sectional view of the sixth preferred embodiment of the present invention;

Fig. 8 is a sectional view of a seventh preferred embodiment of the present invention;

Fig. 9 is a cross-sectional view of an eighth preferred embodiment of the present invention.

Explanation of the accompanying drawings:

10', negative electrode cover 20', positive electrode material

30′, sealing ring 40′, negative electrode material

50′, positive shell 60′, diaphragm

10. Negative cover 11. Vent

12. Capillary channel 20. Cathode material

30. Sealing ring 40. Anode material

50. Positive electrode case 60. Diaphragm

70. Isolation unit 71. Isolation film

72. Current collector.

Detailed ways

Please refer to shown in Fig. 2, it has shown the specific structure of the first preferred embodiment of the present invention, comprises a negative electrode cover 10, a positive electrode material 20, a sealing ring 30, a negative electrode material that is conducted with the negative electrode cover 10 40 , a positive electrode case 50 and a separator 60 for isolating the positive electrode material 20 and the negative electrode material 40 .

The positive electrode case 50 and the negative electrode cover 10 are fastened and connected; the sealing ring 30 is sandwiched between the positive electrode case 50 and the negative electrode cover 10 to isolate the positive electrode case 50 and the negative electrode cover 10 from each other; the positive electrode material 20 is arranged on the positive electrode case 50, the separator 60 is arranged above the positive electrode material 20, the negative electrode material 40 is installed between the negative electrode cover 10 and the separator 60, and the negative electrode material 40 is mercury-free and lead-free zinc paste.

Wherein, the negative electrode cover 10 is punched from iron sheet or other iron-based metal sheet, and the surface of the negative electrode cover is at least plated with a layer of nickel, of course, other metal layers can also be plated, such as gold plating, so that the shape of the negative electrode cover 10 more beautiful, or the negative electrode cover 10 is punched directly from a pre-plated metal sheet or a laminated metal sheet; The laminated metal sheet is nickel/stainless steel/nickel, or nickel/iron/nickel, or nickel/stainless steel/copper, or a three-layer composite steel strip of nickel/iron/copper, or a two-layer composite steel strip of nickel/stainless steel, Not to be limited; this negative cover 10 is provided with vent 11, and this vent 11 is positioned at the side edge of negative cover 10, and this vent 11 is used for discharging the hydrogen that produces when hydrogen evolution reaction occurs inside the battery, avoids gas accumulation The inside of the button battery will cause the button battery to swell, leak or even explode.

And, an isolation unit 70 is provided between the negative electrode cover 10 and the negative electrode material 40 for isolating the negative electrode material 40 and the negative electrode cover 10 from each other and simultaneously connecting the negative electrode material 40 and the negative electrode cover 10 . In this embodiment, the isolation unit 70 includes an isolation film 71 and a current collector 72. The isolation film 71 is arranged on the inner surface of the negative electrode cover 10 to isolate the negative electrode material 40 from the negative electrode cover 10. The isolation film 71 Be arranged on the inner surface of the negative pole cover 10 and cover the outer ring body of the negative pole cover 10 (i.e. the ring body beyond the bead diameter of the negative pole cover 10, the bead diameter is the maximum diameter of the bead body of the negative pole cover 10, the cross section of the ring body J-type), the periphery of the isolation membrane 71 is sealed and connected with the sealing ring 30, so as to prevent the negative electrode material 40 from contacting the negative electrode cover 10 and causing hydrogen evolution reaction; Alkali material, this material is PP material or PVC material or PA material or PE material or PTFE material or their modified material; Since negative electrode material 40 all contains a small amount of metal impurities with low hydrogen evolution overpotential, such as iron etc., these impurities After the battery is continuously discharged under a heavy load, it is easy to undergo a hydrogen evolution reaction with the zinc paste to generate hydrogen gas. The gas can pass through the isolation film 71 and be discharged through the aforementioned vent hole 11 to prevent the battery from inflating, leaking or even exploding; The body 72 is a metal material that cannot react with the negative electrode material 40 for hydrogen evolution, the metal material is a pure copper material or a copper-based alloy material, and the current collector 72 is plated with indium or tin or an indium-tin alloy; in this embodiment , the current collector 72 is a pure copper material. When the purity of the pure copper material reaches 99.999% or more (including 99.999%), it may also not be limited to indium-plated or tin-plated or indium-tin alloy-plated; and, in In this embodiment, the current collector 72 is a wire, and the wire is conductively connected between the negative electrode material 40 and the negative electrode cover 10, and the two ends of the conductive wire are respectively connected to the outer ring of the negative electrode cover 10, and the conductive wire The middle part of the wire is conductively connected with the negative electrode material 40, and the middle part of the wire is straight and perpendicular to the central axis of the battery.

Please refer to shown in Fig. 3, it shows the specific structure of the second preferred embodiment of the present invention, the specific structure of this embodiment is basically the same as the specific structure of the aforementioned first preferred embodiment, the difference is: in In the present embodiment, the separator 71 is arranged on the inner surface of the negative electrode cover 10 and covers the top of the outer ring body of the negative electrode cover 10. The top surface of the outer ring body to the top surface of the negative electrode cover 10) conduction connection, thereby increasing the contact area between the wire and the separator 71 and the sealing ring 30, so that the negative electrode cover 10 and the positive electrode case 50 The sealing performance between them is better, and it is more effective to prevent the occurrence of liquid leakage.

Please refer to shown in Figure 4, which shows the specific structure of the third preferred embodiment of the present invention, the specific structure of this embodiment is basically the same as the specific structure of the aforementioned second preferred embodiment, the difference is: in In this embodiment, the current collector 72 is an annular body, the cross section of the annular body is L-shaped, the bottom of the annular body is conductively connected with the negative electrode material 40, and the top of the annular body is conductively connected with the bead body of the negative electrode cover 10 Connection, whereby, by using the annular body as the current collector, the assembly of the product can be made more convenient, and the conduction connection is more reliable.

Please refer to shown in Figure 5, which shows the specific structure of the fourth preferred embodiment of the present invention, the specific structure of this embodiment is basically the same as the specific structure of the aforementioned first preferred embodiment, the difference is: in In the present embodiment, the isolation unit 70 is a conductive film, which replaces the isolation film 71 and the current collector 72 in the first preferred embodiment, and the conductive film is arranged on the inner surface of the negative electrode cover 10 to cover the negative electrode material 40 and the negative electrode cover 10 are separated from each other and the conductive film is conductively connected between the negative electrode material 40 and the negative electrode cover 10; At the bottom of the outer ring body, the periphery of the conductive film is sealed and connected with the sealing ring 30 to prevent the negative electrode material 40 from contacting the negative electrode cover 10 to cause hydrogen evolution reaction; The material is a graphite-based composite material or a carbon black-based composite material or a hydrogen-permeable alloy material or a hydrogen-permeable alloy composite material; since the negative electrode material 40 contains a small amount of metal impurities with low hydrogen evolution overpotential, such as iron, these impurities After the battery is continuously discharged under heavy load, it is easy to undergo hydrogen evolution reaction with the zinc paste to generate hydrogen gas. The gas can pass through the conductive film and be discharged through the aforementioned vent hole 11 to prevent battery inflation, liquid leakage or even explosion.

Please refer to Fig. 6, which shows the specific structure of the fifth preferred embodiment of the present invention, the specific structure of this embodiment is basically the same as that of the aforementioned fourth preferred embodiment, the difference is: In this embodiment, the conductive film is arranged on the inner surface of the negative electrode cover 10 and covers the top of the outer ring body of the negative electrode cover 10, thereby increasing the contact area between the conductive film and the sealing ring 30, so that the negative electrode cover 10 The sealing performance with the positive electrode case 50 is better, and the occurrence of liquid leakage can be more effectively prevented.

Please refer to shown in Figure 7, which shows the specific structure of the sixth preferred embodiment of the present invention, the specific structure of this embodiment is basically the same as the specific structure of the aforementioned second preferred embodiment, the difference is: In the present embodiment, the negative electrode cover 10 is not provided with an exhaust hole 11, but between the outer ring body of the negative electrode cover 10 and the isolation film 71 of the isolation unit 70, an exhaust capillary channel 12 is arranged, and these capillary channels 12 replaces the exhaust hole 11 in the aforementioned second preferred embodiment, and uses these capillary channels 12 to discharge the hydrogen gas generated when the hydrogen evolution reaction occurs inside the button battery, so as to avoid the accumulation of gas inside the button battery and make the button battery gas Swelling, leakage or even explosion, further improving the safety of product use.

Please refer to Fig. 8, which shows the specific structure of the seventh preferred embodiment of the present invention, the specific structure of this embodiment is basically the same as that of the aforementioned third preferred embodiment, the difference is: In the present embodiment, the negative electrode cover 10 is not provided with an exhaust hole 11, but between the outer ring body of the negative electrode cover 10 and the isolation film 71 of the isolation unit 70, an exhaust capillary channel 12 is arranged, and these capillary channels 12 replaces the exhaust hole 11 in the aforementioned third preferred embodiment, and uses these capillary channels 12 to discharge the hydrogen gas generated when the hydrogen evolution reaction occurs inside the button battery, so as to avoid the accumulation of gas inside the button battery and make the button battery gas Swelling, leakage or even explosion, further improving the safety of product use.

Please refer to Fig. 9, which shows the specific structure of the eighth preferred embodiment of the present invention, the specific structure of this embodiment is basically the same as that of the aforementioned fifth preferred embodiment, the difference is: In the present embodiment, no vent hole 11 is provided on the negative electrode cover 10, but capillary passages 12 for exhaust are arranged between the outer ring body of the negative electrode cover 10 and the conductive film of the isolation unit 70, and these capillary passages 12 Instead of the exhaust holes 11 in the fifth preferred embodiment, the capillary channels 12 are used to discharge the hydrogen gas generated when the hydrogen evolution reaction occurs inside the button battery, so as to prevent the gas from accumulating inside the button battery and causing the button battery to swell , leakage or even explosion, further improving the safety of product use.

In conjunction with the embodiment shown in FIGS. 7 to 9 , when the isolation film 71 or conductive film in the isolation unit 70 covers the top of the outer ring body of the negative electrode cover 10 , the present invention can be placed on the outer ring of the negative electrode cover 10 An exhaust capillary channel 12 is provided between the body and the isolation unit 70 to replace the design of the exhaust hole 11 .

The key points of the design of the present invention are: firstly, by providing an isolation unit between the negative electrode cover and the negative electrode material, the conductive film is used to separate the negative electrode cover from the negative electrode material to prevent the negative electrode material from contacting with the negative electrode cover to cause hydrogen evolution reaction, thereby replacing The existing form of separating the negative electrode material from the base metal of the negative electrode cover by indium plating or tin plating. In this way, on the one hand, it is beneficial to ensure that the negative electrode material and the negative electrode cover are kept separated, effectively avoiding the contact between the negative electrode material and the negative electrode cover, which will cause the product to appear inflated, leak or even explode, and eliminate potential safety hazards. The safety of product use Better; on the other hand, the present invention does not need to use indium plating or tin plating in the production of the negative electrode cover, effectively avoiding the need to discharge or containing indium or chromium or containing The environmental pollution caused by the industrial sewage of copper and other heavy metal ions is beneficial to environmental protection, and it also reduces the production cost of enterprises and reduces the burden on enterprises. Secondly, by providing a vent hole on the negative electrode cover or a capillary channel for exhausting between the outer ring body of the negative electrode cover and the isolation unit, the hydrogen evolution inside the button battery is depleted by using the vent hole or these capillary channels. The hydrogen gas produced during the reaction is discharged to prevent the gas from accumulating inside the button battery, causing the button battery to swell, leak or even explode, and further improve the safety of the product.

The above descriptions are only preferred embodiments of the present invention, and do not limit the technical scope of the present invention in any way, so any minor modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention are still valid. It belongs to the scope of the technical solutions of the present invention.

Claims (7)

1. A mercury-free and lead-free button cell, comprising a negative cover, a positive material, a sealing ring, a positive shell, a negative material connected with the negative cover, and one for isolating the positive material and the negative material Diaphragm; the positive electrode case and the negative electrode cover are buckled and connected; the sealing ring is sandwiched between the positive electrode case and the negative electrode cover to isolate the positive electrode case and the negative electrode cover from each other; the positive electrode material is arranged on the inner bottom of the positive electrode case, and the diaphragm It is arranged above the positive electrode material, and the negative electrode material is installed between the negative electrode cover and the separator; it is characterized in that: there is a device between the negative electrode cover and the negative electrode material for isolating the negative electrode material and the negative electrode cover from each other and simultaneously separating the negative electrode material and the negative electrode material. The isolation unit of the negative electrode cover conduction connection, the isolation unit is a conductive film, the conductive film is arranged on the inner surface of the negative electrode cover and covers the bottom or top of the outer ring body of the negative electrode cover or between the bottom and the top, the conductive film will The negative electrode material and the negative electrode cover are isolated from each other, and the conductive film is conductively connected between the negative electrode material and the negative electrode cover. 2. The mercury-free and lead-free button battery according to claim 1, characterized in that: the conductive film is a highly alkali-resistant conductive material that is hydrogen permeable and impermeable to electrolyte, and the material is a graphite-based composite material Or carbon black-based composite material or hydrogen permeable alloy material or hydrogen permeable alloy composite material. 3. The mercury-free and lead-free button battery according to claim 1, characterized in that: the negative electrode cover is provided with an air vent or between the outer ring body of the negative electrode cover and the isolation unit. capillary channel. 4. The mercury-free and lead-free button battery according to claim 1, characterized in that: the negative electrode cover is punched from an iron sheet or an iron-based metal sheet, and the surface of the negative electrode cover is at least coated with a layer of nickel, Alternatively, the negative electrode cover is punched directly from pre-plated metal sheets or laminated metal sheets. 5 . The mercury-free and lead-free button battery according to claim 4 , wherein the pre-plated metal sheet is a nickel-plated steel strip or a steel strip with nickel plating on one side and copper plating on the other side. 6. The mercury-free and lead-free button battery according to claim 4, characterized in that: the laminated metal sheet is nickel/stainless steel/nickel, or nickel/iron/nickel, or nickel/stainless steel/copper, or Three-layer composite steel strip of nickel/iron/copper, or two-layer composite steel strip of nickel/stainless steel. 7. The mercury-free and lead-free button battery according to claim 1, characterized in that: the negative electrode material is mercury-free and lead-free zinc paste.

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