CN102891286A

CN102891286A - Electrode for disposable alkaline cell

Info

Publication number: CN102891286A
Application number: CN2012103584250A
Authority: CN
Inventors: 虞伟财
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-09-21
Filing date: 2012-09-21
Publication date: 2013-01-23

Abstract

The present invention relates to an electrode for a disposable alkaline battery comprising an anode material and a cathode material, a separator between the anode and the cathode, an alkaline electrolyte, an anode current collector, a gel; the cathode material comprises cathode active materials of manganese dioxide, hydroxyl nickel oxide and conductive carbon particles; the anode material is zinc or zinc alloy and graphite.

Description

Electrode for disposable alkaline cell

Technical Field

The invention belongs to the field of batteries, and particularly relates to an electrode material of a disposable alkaline battery.

Background

A disposable alkaline battery includes an anode, a cathode, an electrolyte permeable separator between the anode and the cathode, and an alkaline electrolyte. The anode comprises an anode active material, now predominantly zinc or zinc alloy particles and a conventional gelling agent for fixing the zinc particles in suspension so that the zinc particles can contact each other, an anode current collector inserted into the gelled zinc electrode, an alkaline electrolyte, typically an aqueous solution of potassium hydroxide, also sodium hydroxide or lithium hydroxide, and a cathode comprising a cathode active material comprising manganese dioxide or nickel oxyhydroxide or mixtures thereof and a conductive additive such as graphite and the like.

The current disposable alkaline batteries are limited by commercial models, the capacity in the batteries is fixed, in order to increase the battery capacity, i.e. the service life of the batteries or the higher power consumption of the batteries to meet the requirements of some high-power electric appliances, the method of increasing the interfacial surface area of the electrode active materials and increasing the active materials in the batteries are generally adopted, and the method of increasing the density of the active materials generally cannot meet the requirements of high power because the electrochemical reaction rate is reduced in the discharging process due to the increase of the density after the density of the active materials reaches a certain degree.

Another problem of the zinc-manganese disposable alkaline batteries which are mainly used at present is that the batteries have a characteristic inclined voltage characteristic, that is, the average operating voltage of the batteries gradually decreases when the batteries are discharged, and the voltage decreases at a significant rate when the batteries are consumed at a high power, so that the actual battery capacity of the zinc-manganese batteries obtained at a high power is smaller than that of the batteries at a low power consumption, and thus the zinc-manganese batteries are not suitable for high power consumption electric appliances such as cameras and the like. In order to realize disposable alkaline batteries that can be used at high power, disposable alkaline batteries have been produced mainly using nickel oxyhydroxide as a cathode active material or using nickel oxyhydroxide and manganese dioxide in a weight ratio of 1: 1 as a cathode active material, but nickel oxyhydroxide is much more costly than manganese dioxide.

When the existing disposable alkaline battery is analyzed after being used, no matter manganese dioxide or nickel oxyhydroxide is used as a cathode active material, 15-25% of zinc in the original weight in the anode of the battery is not reacted and is discarded. It has been found that the problem for this reason is not that the proportion of zinc is not discharged by reaction but that when the proportion of zinc in the battery reaches to such a proportion, the chemical reaction rate decreases due to the increase in resistance in the battery and the amount of electricity generated is not practically used, and such unusable batteries still undergo a slow electrochemical reaction until the anode active material or the cathode active material in the battery is completely reacted.

Therefore, there is a need for a disposable alkaline cell that has a longer service life at high power and more complete reaction of the materials within the cell.

Disclosure of Invention

The main object of the present invention is to reduce the production costs while ensuring that the disposable alkaline battery is suitable for high power consumption and has a service life similar to that of nickel oxyhydroxide as a cathode active material.

Another object of the present invention is to reduce the consumption of resources by allowing the cathode and anode active materials in the battery to react as thoroughly as possible at the end of the battery's life.

The invention is realized by the following technical scheme:

the percentages referred to in the present invention are percentages by weight.

An electrode for a disposable alkaline cell comprising an anode material and a cathode material, a separator between the anode and cathode, an alkaline electrolyte, an anode current collector, a gel; the cathode material comprises cathode active materials of manganese dioxide, hydroxyl nickel oxide and conductive carbon particles; the anode material is zinc or zinc alloy and graphite; the graphite accounts for 5-8% of the weight of the anode material; the manganese dioxide accounts for 85 to 90 percent of the cathode active material; the nickel oxyhydroxide accounts for 10 to 15 percent of the cathode active material; the conductive carbon particles account for 30% -35% of the cathode material; the concentration of the alkaline electrolyte aqueous solution is 53-60%; the gels accounted for 3% of the anode and cathode materials, respectively.

The anode material of the alkaline battery contains 0.01-0.03% of metal or metal oxide for preventing hydrogen generation, wherein the metal or metal oxide refers to one or two of bismuth, indium and germanium and aluminum or aluminum oxide.

The anode material of the alkaline battery, namely zinc or zinc alloy, comprises 0.015 to 0.025 percent of aluminum.

The alkaline electrolyte is potassium hydroxide, sodium hydroxide or lithium hydroxide.

The invention has the beneficial effects that:

by the technical scheme, a certain amount of graphite is added into the anode material, so that the phenomenon that the oxide surface layer generated after the reaction of zinc in the anode obstructs the reaction speed and reduces the transmission speed of electrons at the later stage of the electrochemical reaction of the battery can be effectively prevented, the chemical reaction can be stably carried out, and the voltage stability is ensured.

2, by using a small amount of nickel oxyhydroxide in the cathode active material, it is possible to improve a certain amount of reaction rate while reducing the amount of nickel oxyhydroxide used in the prior art and improve the completeness of the reaction by using a high concentration of electrolyte.

Detailed Description

The technical contents of the present invention are described in detail below by way of specific embodiments, which are exemplary and are only used for explaining the contents of the present invention and are not construed as limiting the present invention.

The invention is realized by the following embodiments:

a disposable alkaline cell comprising an anode material and a cathode material, a separator between the anode and cathode, an alkaline electrolyte, an anode current collector, a gel, and a cell housing; the cathode material comprises cathode active materials of manganese dioxide, hydroxyl nickel oxide and conductive carbon particles; the anode material is zinc or zinc alloy and graphite; the graphite accounts for 5-8% of the weight of the anode material.

Example one

In a specific embodiment of the invention, the zinc or zinc alloy in the anode material is in the form of particles, and the particles are roughly in two modes, one is particles with about 200 meshes, and the other is particles with about 10-30 meshes, and the ratio of the two types of particles is 3: 10-4: 10; 10-30 nano particles are adopted in the graphite accounting for 5 percent of the weight of the anode material; the zinc or zinc alloy comprises 0.015-0.025% of aluminum; if the zinc metal is adopted in the embodiment, the aluminum is mixed in the mode of aluminum powder or alumina powder according to the content of the aluminum; if zinc alloy is used in the examples, it is added in proportion in the production of zinc alloy. The purpose of adding aluminum into zinc or zinc alloy is to inhibit the generation of hydrogen, the purpose of the proportion is to ensure that the content of aluminum in the electrolyte is 30-75ppm, and if the content of aluminum in the electrolyte is lower than 30ppm, although the effect of inhibiting hydrogen is achieved to a certain extent, the hydrogen generated by the battery in the effective life of the battery cannot be ensured to be in an allowable range; if the content of aluminum in the electrolyte is more than 75ppm, the generation of hydrogen gas can be suppressed, but a part of the short circuit is caused, which affects the efficiency of the battery. In other embodiments of the present invention, the hydrogen suppressing agent may be one or two of bismuth, indium or germanium metal or metal oxide. In this example, the selected alkaline electrolyte is 53% to 60% potassium hydroxide aqueous solution, and the concentration of the selected alkaline electrolyte solution is higher than that of the electrolyte solution of 40% to 50% used in the prior art, and according to the analysis of the inventors, if the concentration of the used electrolyte is low, the voltage is rapidly decreased in the later period of the battery life, and if the concentration of the electrolyte is too high, the efficiency of the battery in the initial period is affected, and through the research of the inventors, when the concentration of the electrolyte is 53% to 60%, the efficiency of the battery can be best exerted, especially when the concentration is 55%.

The gel used in the present invention is the prior art and conventional ratio of 3%, and will not be described herein too much.

The anode current collector adopted by the invention adopts a hollow metal net, the mesh is 700-1200 meshes, preferably 800 meshes, and the 800 meshes are adopted in the embodiment and the following embodiments.

The separator is a material for separating the anode and the cathode without change from the prior art.

The cathode material comprises cathode active materials of manganese dioxide, hydroxyl nickel oxide and conductive carbon particles; the manganese dioxide accounts for 85% -90% of the cathode active material; the nickel oxyhydroxide accounts for 10 to 15 percent of the cathode active material; the conductive carbon particles account for 30-35% of the cathode material, the amount of the nickel oxyhydroxide used in the invention is 0.2-0.3 times of that of the prior art, and the part of the nickel oxyhydroxide can also realize the purpose of improving the cathode reaction efficiency, and the technical improvement of the anode and the electrolyte of the technology is matched to realize that the battery can be suitable for high-power electric appliances.

In this example, the anode current collector, separator, and gel used were the same as in the following examples, and are not repeated here. The following examples of the present invention are different from the present embodiment only in specific gravity of the materials, and the rest are the same, and the materials having different proportions will be described in detail below.

Example two

In this embodiment, the anode active material is metal zinc or zinc alloy, the proportion of graphite in the anode is 6%, the selected aluminum or aluminum oxide accounts for 0.025% of the amount of zinc, and one or two metals or metal oxides of bismuth, indium and germanium mentioned in the technical solution may also be selected; the manganese dioxide accounts for 85 percent of the cathode active material, the nickel oxyhydroxide accounts for 15 percent of the cathode active material, the conductive carbon particles in the cathode adopt 35 percent of graphite, and other conductive carbon particles can also be adopted; the alkaline electrolyte is 55% potassium hydroxide aqueous solution, and of course, sodium hydroxide or lithium hydroxide can be selected at this concentration to realize the present invention, but potassium hydroxide is preferred in terms of the efficiency and economy of the battery. Aluminum is chosen as the hydrogen inhibitor in the examples of the present invention because it is most economical.

EXAMPLE III

In this embodiment, the anode active material is metal zinc or zinc alloy, the proportion of graphite in the anode is 8%, the selected aluminum or aluminum oxide accounts for 0.015% of the amount of zinc, and one or two metals or metal oxides of bismuth, indium and germanium in the technical solution may also be selected; the cathode active material comprises 90% of manganese dioxide, 10% of nickel oxyhydroxide, 30% of graphite as conductive carbon particles in the cathode, and other conductive carbon particles can be selected; the alkaline electrolyte is 53% potassium hydroxide aqueous solution, and of course, sodium hydroxide or lithium hydroxide can be selected at this concentration to realize the invention, but potassium hydroxide is preferred from the viewpoint of battery performance and economy.

Example four

In this embodiment, the anode active material is metal zinc or zinc alloy, the proportion of graphite in the anode is 7%, the selected aluminum or aluminum oxide accounts for 0.020% of the amount of zinc, and one or two metals or metal oxides of bismuth, indium and germanium in the technical scheme can also be selected; the cathode active material comprises 88% of manganese dioxide, 12% of nickel oxyhydroxide, 33% of graphite as conductive carbon particles in the cathode, and other conductive carbon particles can be selected; the alkaline electrolyte is 60% potassium hydroxide aqueous solution, and of course, sodium hydroxide or lithium hydroxide can be selected at the concentration to realize the invention, but potassium hydroxide is preferred from the aspects of battery efficiency and economy.

EXAMPLE five

In this embodiment, the anode active material is metal zinc or zinc metal, the proportion of graphite in the anode is 6.5%, the selected aluminum or aluminum oxide accounts for 0.015% of the zinc, or one or two metals or metal oxides of bismuth, indium and germanium in the technical solution can be selected; the cathode active material comprises 90% of manganese dioxide, 10% of nickel oxyhydroxide, 35% of graphite as conductive carbon particles in the cathode, and other conductive carbon particles can be selected; the alkaline electrolyte is 55% potassium hydroxide aqueous solution, and of course, sodium hydroxide or lithium hydroxide can be selected at this concentration to realize the invention, but potassium hydroxide is preferred from the aspect of battery efficiency and economy. This embodiment is the best mode of carrying out the invention in all its technical aspects.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. An electrode for a disposable alkaline cell comprising an anode material and a cathode material, a separator between the anode and cathode, an alkaline electrolyte, an anode current collector, a gel; the method is characterized in that: the cathode material comprises cathode active materials of manganese dioxide, hydroxyl nickel oxide and conductive carbon particles; the anode material is zinc or zinc alloy and graphite; the graphite accounts for 5-8% of the weight of the anode material; the manganese dioxide accounts for 85% -90% of the cathode active material; the nickel oxyhydroxide accounts for 10 to 15 percent of the cathode active material; the conductive carbon particles account for 30% -35% of the cathode material; the concentration of the alkaline electrolyte aqueous solution is 53-60%; the gel accounts for 3% of the anode material and the cathode material respectively; the anode current collector is a hollow metal mesh, and the hollow metal mesh is 700-1200 meshes.

2. The electrode for disposable alkaline batteries according to claim 1, characterized in that: the anode material of the alkaline battery contains 0.01-0.03% of metal or metal oxide for preventing hydrogen generation, wherein the metal or metal oxide refers to one or two of bismuth, indium and germanium and aluminum or aluminum oxide.

3. The electrode for disposable alkaline batteries according to claim 2, characterized in that: the aluminum or aluminum oxide accounts for 0.015-0.025 percent of zinc in the anode material.

4. The electrode for a disposable alkaline battery as set forth in claim 2 or 3, characterized in that: the concentration of the aluminum or aluminum oxide in the alkaline electrolyte is 30-75ppm.

5. The electrode for disposable alkaline batteries according to claim 1, characterized in that: the alkaline electrolyte is potassium hydroxide, sodium hydroxide or lithium hydroxide.

6. The electrode for disposable alkaline batteries according to claim 1 or 5, characterized in that: the concentration of the aqueous alkaline electrolyte solution was 55%.

7. The electrode for disposable alkaline batteries according to claim 1, characterized in that: the hollow metal mesh is 800 meshes.