PL237725B1 - Method for producing positive electrode for dry manganese battery, a positive electrode for dry manganese battery and method for producing the dry manganese battery - Google Patents

Description

Description of the invention

The present invention relates to a method of manufacturing a positive electrode for a manganese dry battery.

In the past, manganese dry batteries or dry alkaline batteries have been widely used as energy sources for electronic devices (portable devices and computing devices) and portable electric lamps. In the positive electrode for these dry batteries, manganese dioxide was used as the active material and a carbonaceous material (e.g., carbon black, graphite) was used as the conductive material. In the negative electrode, zinc was used as the active material.

Since dry batteries were considered disposable, it would be useful if the source components could be recovered from used dry batteries. In this light, various technical solutions have been tried.

Patent Literature 1, Japanese Patent Laid-Open Publication No. 2007-12527 proposes a method for separating and then collecting, as a metallurgical raw material, a mixture containing manganese dioxide and carbon material from a spent manganese dry battery and a spent alkaline dry battery.

Patent Literature 2, Japanese Patent Laid-open Publication No. Sho 61-74692 proposes a method of collecting manganese dust from a spent manganese dry battery and a spent alkaline dry battery.

Materials collected from used dry manganese batteries and used dry alkaline batteries include manganese and carbon materials. Thus, it would be of advantage if such materials could be used as a positive electrode material for manganese dry batteries. However, with regard to the materials collected from used dry batteries, the activity and / or characteristic, such as storageability, is reduced.

It is usually difficult to industrially and completely recycle used materials. For example, if the mixture collected by the method of Patent Literature 1 is actually used as a positive electrode material, problems will readily arise in the mixing of the materials and / or the forming process into a positive electrode. Thus, it will be difficult to form a permanently and uniformly positive electrode, and the efficiency may be reduced.

The following are the reasons for the difficulties when materials collected from used dry batteries are applied to the positive electrode for manganese dry batteries.

The above mixture is difficult to granulate. Thus, the mixture does not obtain a suitable particle size for homogeneous mixing of the positive electrode material, and may take the form of large lumps. When the granulation is insufficient, the positive electrode material has poor fluidity and therefore cannot readily be homogeneously blended with the other ingredients. Thus, it becomes difficult to continuously, stably feed / feed material into the manufacturing machine for uniform molding.

In view of the above, it is an object of the present invention to provide a positive electrode at low cost by making a mixture of the positive electrode material that can be homogeneously mixed in the case where the materials collected from the spent dry manganese battery and / or the spent dry alkaline battery are applied to the material. positive electrode for dry manganese battery.

The present invention relates to a method of manufacturing a positive electrode for a manganese dry battery, the positive electrode comprises manganese dioxide, carbon material and electrolyte, the manganese dioxide comprises a first manganese dioxide recovered from at least one spent manganese dry battery and a spent alkaline dry battery, the carbon material contains the first carbon material recovered with the first manganese dioxide and unused second carbon material, the method comprising:

a first step of producing a positive electrode material mixture by mixing a mixed composition comprising a first manganese dioxide and a first carbon material, a second carbon material, and an electrolyte; and a second step of forming a positive electrode material mixture wherein the Rsc ratio of the second carbon material when the mixed composition amount is 100 wt% is 1 wt%. or more,

Characterized in that the method meets at least one of the following conditions (a1), (a2) and (a3):

(a1) when the manganese ratio of the blended composition is Rm and wt%, the Rsc ratio of the second carbon material in wt%, the amount of the mixed composition is 100 wt%, satisfies the equation (1): -0.0215 Rm ² + 3, 1077 Rm - 92.572 < Rsc < ^{0.0243 Rm 2 - 1.2459 Rm + 22.959;}

(a2) when the proportion of hydrochloric acid insoluble in the blended composition is Ra and wt%, the Rsc proportion of the second carbon material in wt%, the amount of the mixed composition is 100 wt%, satisfies equation (2):

-0.0499 Ra ² + 0.7681 Ra + 8.0355 <Rsc <0.0239 Ra ² - 1, 8621 Ra + 44.074, and the content insoluble in hydrochloric acid is the residue resulting from the heat treatment of the mixed composition in hydrochloric acid with a concentration of 6 mol / 1; and (a3) the manganese dioxide additionally comprises unused second manganese dioxide, and in the first step, the mixed composition, the second manganese dioxide and the second carbon material are mixed.

In the method for producing a positive electrode for a manganese dry battery of the invention, preferably the Rfc ratio of the first carbon material in the blended composition is 6 to 30 wt%.

In the method for producing a positive electrode for a manganese dry battery according to the invention, preferably the proportion Rsc of the second carbon material is 2 to 30 wt%.

In the method for producing a positive electrode for a manganese dry battery according to the invention, preferably the blended composition is obtained by conducting:

a process for crushing the electrode that was contained in at least one spent dry manganese battery and a spent dry alkaline battery to obtain granules, and a process for treating the granules with a dilute acid comprising at least one of hydrochloric acid and sulfuric acid.

In the method for producing a positive electrode for a manganese dry battery according to the invention, preferably the second manganese dioxide is at least one selected from the group consisting of electrolytic manganese dioxide, natural manganese dioxide and chemical manganese dioxide.

According to the present invention, in the case where the positive electrode for the manganese dry battery is produced using materials collected from the spent dry manganese battery and / or the spent dry alkaline battery, the positive electrode material can be homogeneously mixed by a simple method. It also can improve the performance of the positive electrode for the dry manganese battery as well as the performance of the dry manganese battery.

Brief Description of Drawings

Fig. 1 is a schematic sectional view in a partial cut off of a size D manganese dry battery.

Fig. 2 is a graph showing the relationship between the Rm ratio of manganese and the Rsc ratio of the second carbon material in Example 6.

Fig. 3 is a graph showing the relationship between the Ra ratio of the hydrochloric acid insoluble content and the ratio Rsc of the second carbon material in Example 7.

In the method of manufacturing a positive electrode for a manganese dry battery of the invention, the positive electrode comprises manganese dioxide, a carbon material and an electrolyte, the manganese dioxide containing the first manganese dioxide recovered from the spent manganese dry battery and / or spent alkaline dry battery, and the carbon material comprises the first material. carbon recovered with the first manganese dioxide and unused second carbon material. The method of producing a positive electrode comprises: a first step of producing a positive electrode material mixture by mixing a mixed composition comprising a first manganese dioxide and a first carbon material, a second carbon material, and an electrolyte; and a second step of forming the positive electrode material mixture. Here, the Rsc proportion of the second carbon material is 1 wt%. % or more when the amount of the mixed composition is 100 wt.%.

Regarding collected batteries: spent dry manganese batteries and / or spent dry alkaline batteries, the ratio between dry manganese batteries and dry alkaline batteries varies according to the country or area where they are collected and is not definitive. Moreover, the composition of materials (electrode materials such as positive electrode material) in dry batteries is different

Depending on the manufacturer and / or the grade of dry batteries. As a result, the composition of the materials recovered from the collected batteries is not homogeneous.

Since the positive electrode material recovered from the harvested batteries was formed into a positive electrode, has been in contact with the electrolyte, has been discharged, and has undergone a recovery process, there is a difference in properties between such positive electrode material and the unused positive electrode material. The recovered positive electrode material has low graininess, may take the form of lumps, it is difficult to obtain an average particle size (about 1 to 3 mm) suitable for positive electrode formation, and it has low flowability. Thus, when such a positive electrode material is mixed with other components of the positive electrode to form a new positive electrode, it will be difficult to mix the mixture homogeneously and, moreover, to stably feed the mixture into a positive electrode molding process.

In the method of the present invention, a specific amount of unused second carbon material is mixed into a mixed composition comprising a first manganese dioxide and a first carbon material recovered from a spent manganese dry battery and / or a spent alkaline dry battery. This facilitates homogeneous mixing in the preparation of the positive electrode material mixture as it becomes easier to accommodate variability in the formulation of the mixed composition and possibly reduce the difficulty of the forming process, such difficulties deriving from a reduction in the fluidity of the positive electrode material mixture or the like. By virtue of the considerably simple technique of mixing unused second carbon material into the blended composition, the positive electrode for the manganese dry battery can be re-fabricated from the recovered positive electrode material (mixed composition above). Thus, the above method is low cost.

The method of producing a positive electrode for a manganese dry battery according to the present invention comprises: a first step of producing a positive electrode material mixture; and a second step of forming the positive electrode material mixture. In the first step, a mixed composition comprising a first manganese dioxide and a first carbon material (also referred to simply as the mixed composition), a second carbon material, and an electrolyte are mixed to form a positive electrode material mixture. The first manganese dioxide is recovered from the spent manganese dry battery and / or the spent alkaline dry battery, and the first carbon material is recovered along with the first manganese dioxide. The second carbon material is not recovered from the spent product as with the first carbon material, but is unused fresh carbon material.

Typically, the positive electrode for manganese dry batteries includes manganese dioxide as the active material of the positive electrode, carbon material as the conductive material, and electrolyte. The manganese dioxide in the positive electrode includes the first manganese dioxide, and the carbon material, which includes the first carbon material and the second carbon material.

In the first step, the mixed composition, the second carbon material, and the electrolyte are mixed to form a positive electrode material mixture. Here, it is important that blending results in an Rsc proportion of the second carbon material of 1 wt%. % or more when the amount of the mixed composition is 100 wt.%. Accordingly, the components of the positive electrode material mixture can be homogeneously mixed despite using the mixed composition that has been recovered, and the formation of the positive electrode material mixture can be improved. Moreover, as the flowability of the positive electrode material mixture increases, the performance of the positive electrode as well as the manganese dry battery can also be improved.

Typically, the positive electrode for dry manganese batteries or dry alkaline batteries includes manganese dioxide as the active material of the positive electrode. The manganese dioxide (first manganese dioxide) recovered from the spent manganese dry battery and / or the spent dry alkaline battery is used as the active positive electrode material for the manganese dry battery.

Typically, the positive electrode for manganese dry batteries includes carbon black as the conductive material (carbon material) and the positive electrode for dry alkaline batteries includes graphite as the conductive material (carbon material). Thus, the mixed composition includes graphite, carbon black, and / or the like as the first carbon material. Examples of graphite include carbonaceous material having a graphite-type crystalline structure over a large surface area. Examples of carbon black include acetylene black, furnace black, and thermal black. The blended composition can include one first carbon material or two or more first carbon materials.

Typically, the positive electrode for manganese dry batteries comprises manganese dioxide and a conductive material (e.g., carbon black) in a weight ratio ranging from 3: 1 to 8: 1. Zwy

The positive electrode for dry alkaline batteries comprises manganese dioxide and a conductive material (e.g., graphite) in a weight ratio ranging from 10: 1 to 25: 1. These ratios vary according to the manufacturer of the dry battery and the classification of dry batteries (type) and also vary depending on the country or area where the waste dry batteries are collected.

The Rfc proportion of the first carbon material in the blended composition may be, for example, from 6 to 30 wt%, from 8 to 25 wt%. or from 10 to 20 wt.%. A mixed composition having an Rfc ratio within the above range is easy to obtain.

The proportion Rfm of the first manganese dioxide in the blended composition may be, for example, 30 to 90 wt%, 50 to 88 wt%. or from 65 to 85 wt.%. A mixed composition having an Rfm ratio within the above range is easy to obtain.

In a mixed composition recovered from dry batteries, where the Rfc ratio and / or the Rfm ratio varies greatly between batches, the Rfc ratio and / or the Rfm ratio can be adjusted by combining multiple batches.

The Rfc ratio and the Rfm ratio can be obtained as below. First, the mixed composition is treated with heat (heated, e.g., 100 to 200 ° C (e.g., 160 ° C) for 0.5 to 3 hours (e.g., 1 hour)) in 6 mol / L hydrochloric acid. % (about 18.5 wt.%) to separate it into an insoluble content (content insoluble in hydrochloric acid) and a solution. The hydrochloric acid-insoluble content can be dried and then subjected to thermogravimetric analysis to obtain the percent weight loss (especially, percent weight loss from 400 to 900 ° C) of the carbon content, which can then be converted to the Rfc (wt%) ratio. the first carbon material in the mixed composition.

The remaining solution after separation from the hydrochloric acid insoluble content can be subjected to coupled plasma induced atomic emission spectroscopy (ICP) to obtain the Rm (wt%) ratio of manganese in the blended composition, which can then be converted to the Rfm ratio ( wt.%) of the first manganese dioxide. It should be noted that the hydrochloric acid insoluble content of the mixed composition may refer to the residue resulting from the mixed composition treated with heat in 6 mol / L hydrochloric acid.

The mixed composition can be obtained by a known method. For example, there may be a method in which the mixed composition is obtained here by carrying out a recovery process for a spent manganese dry battery and / or a spent dry alkaline battery. As long as the mixed composition comprises manganese dioxide and a carbon conductive material (the first carbon material), the recovery method is not particularly limited. The resulting material of collecting only positive electrodes from dry batteries and then carrying out a recovery process from them can be used as a blended composition; or the resultant material of the recovery process from the content of dry batteries can be used as a blended composition.

In a preferred embodiment, the mixed composition to be used can be obtained by carrying out the step of crushing the electrodes (positive electrodes, or positive electrodes and negative electrodes) that were in the spent manganese dry battery and / or spent alkaline dry battery to obtaining granules; and a step of treating (or washing) the granules with a dilute acid containing hydrochloric acid and / or sulfuric acid. Especially, the mixed composition recovered by the method disclosed in Patent Literature 1 or 2, for example, can be used. Particularly, the mixed composition recovered by the method disclosed in Patent Literature 1 is preferably used. In negative electrodes in dry manganese battery and dry alkaline battery, zinc is used as the active material of the negative electrode. Even when the materials collected from such dry batteries contain zinc, the zinc can be dissolved and removed by dilute acid treatment and the positive electrode material can be recovered in this way. The blended composition is preferably in the form of particles or a powder.

The concentration of hydrochloric acid in the dilute acid is preferably 14 wt.%. % or less and may be from 1 to 10 wt.%. or from 2 to 8 wt.%. The concentration of the sulfuric acid in the dilute acid is preferably 45% by weight. % or less and may be from 1 to 30 wt.%. or from 4 to 20 wt.%. When the concentration of hydrochloric acid or the concentration of sulfuric acid in the dilute acid is within the above range, it is easier to increase the collection rate of manganese dioxide.

The second carbon material may be arbitrarily selected from the examples that have been mentioned for the first carbon material. One or two or more may be used as the second carbon material

The materials can be used in combination. For reasons of electrolyte conductivity and / or retention, the second carbon material preferably comprises carbon black; and because of its high conductivity, the second carbon material preferably comprises acetylene carbon black. The second carbon material is in the form of a powder.

Typically, the positive electrode material is mixed with the electrolyte and then formed into the positive electrode. Presently, due to the deformation under pressure of the molded article and / or the sticking of the positive electrode material to the mold during molding, it is required that the positive electrode material has an appropriate degree of electrolyte retention. However, the mixed composition recovered from dry batteries differs from the unused positive electrode material in properties and has a lower electrolyte retention. Thus, in molding, demoulding with respect to the positive electrode material becomes difficult and the mold becomes contaminated, thus easily reducing productivity. It should be noted that the electrolyte retention is low in the mixed composition that is recovered, possibly because the factors of forming the positive electrode material into the positive electrode, its contact with the electrolyte, its discharge over time in dry batteries, and also a recovery process such as its treatment by chemical conversion (e.g. acid treatment) causes the carbonaceous material to degrade or the surface of the carbon material to become weakened.

According to the present invention, the Rsc proportion of the second carbon material is 1 wt%. or more. When the Rsc ratio is within the above range, it becomes easier to homogeneously mix the positive electrode material mixture and ensure high fluidity; thus, the positive electrode can be manufactured with consistent quality and high efficiency. Moreover, by adding the second carbon material, the positive electrode material mixture is rendered hydrophilic and the electrolyte retention may increase.

The Rsc proportion of the second carbon material is 1 wt%. % or more and preferably 2 wt.%. % or more or 3 wt.%. or more. The proportion of Rsc is preferably 50 wt.%. % or less, and may be 40 wt.%. % or less or 30 wt.%. or less. These lower limits and higher limits can be arbitrarily combined. The proportion of Rsc may be from 1 to 50% by weight, from 1 to 40% by weight. or from 2 to 30 wt.%.

Preferably, a range for the proportion Rsc (wt%) of the second carbon material may be determined in combination with the proportion Rm (wt%) of the manganese in the blended composition or the proportion Ra (wt%) of the hydrochloric acid insoluble content contained herein.

It should be noted that, as noted above, the hydrochloric acid insoluble content is the residue resulting from the fact that the blended composition is heat treated in 6 mol / l hydrochloric acid and the ratio Ra (wt%) corresponds to the hydrochloric acid insoluble content in mixed composition. The ratio Ra of the hydrochloric acid insoluble content is obtained by sufficiently drying the hydrochloric acid insoluble content that has been separated in the procedure described above to obtain the weight of the dried content, and then calculating the proportion (wt%) of the obtained weight in the blended composition.

Especially first, many batches are produced, each having a different proportion of Rm of manganese; and for each batch, the Rsc proportion of the second carbon material mixed in the blended composition is different, and the miscibility and formability of the positive electrode material blend are estimated. Then, for each batch, a range (upper bound value and lower bound value) of Rsc that allows for high levels of these properties is searched for. For the Rm of each batch, the high limit values and the low Rsc values that allow high values for these properties are plotted. The plotting of the upper bound value and plotting the lower bound Rsc value can be approximated using a linear regression equation; and Rsc shows a high correlation with Rm. Points that deviate upstream from the linear regression equation (line U) for the upper bound value and points that deviate downstream from the linear regression equation (line L) for the lower bound value fall within the previously determined confidence interval of their respective linear regression equations . The previously determined confidence level interval on the upper part of the U line and the previously determined confidence ratio interval on the lower part of the L line, obtained as above, refer to the upper limit and lower limit of Rsc, respectively. Here, the predetermined confidence intervals are preferably 95% confidence intervals.

When the predetermined confidence intervals are 95% confidence intervals, from the upper limit and lower limit obtained as above, the Rsc ratio (wt%) of the second carbon material preferably satisfies equation (1a) as follows:

Rml - t x S <Rsc <Rmu + t x S (1a)

PL 237 725 B1

In equation (1 a), Rmu and Rmi denote the proportions Rm of manganese obtained from the U line and the L line, respectively, and t is the t value (= 3.182) for the 5% confidence level in the t distribution with 3 degrees of freedom. S is the standard deviation and is expressed as [Ve x {(1 / n) + (X + Y)}] ^1/2 . Here, Ve is the error variance, n is the number of data, X is the square of the deviation values for Rmu or Rml, and Y is the sum of the squared deviation values for all data for Rsc.

Accordingly, the range of the Rsc (wt%) ratio of the second carbon material may be determined in combination with the Ra ratio (wt%) of the hydrochloric acid insoluble content. In this case, the Rsc range (wt%) can be obtained according to the case of equation (1a). However, instead of the Rm proportion of the manganese, the Ra proportion of the hydrochloric acid insoluble content is changed to determine the miscibility and formability of the positive electrode material mixture. The plotting of the upper bound value and plotting the lower bound value of Rsc can be approximated by a linear regression equation, and Rsc shows a high correlation with Ra as well.

For the upper limit and lower limit obtained as above, the proportion Rsc (wt%) of the second carbon material preferably satisfies equation (2a) as follows:

Ral - t x S <Rsc <Rau + t x S (2a)

In equation (2a), Rau and Ral are the proportions Ra of the hydrochloric acid insoluble content obtained from the linear regression equation (line U) of the upper limit of Rsc and the linear regression equation (line L) of the lower limit value of Rsc, respectively, with respect to Ra; and t and S have the same meanings as in equation (1a). However, in S, X is the square of the deviation value for the Rau or Ral values.

The proportion Rsc (wt%) of the second carbon material preferably satisfies equation (1a) and / or equation (2a).

By using a second carbon material in a proportion that satisfies equation (1a) above and / or equation (2a) above, the formability of the positive electrode material mixture can be improved, in addition to its miscibility. In particular, a proper degree of electrolyte retention is achieved with the positive electrode material mixture and the occurrence of gaps and / or chipping is reduced in the formed positive electrode. In addition, electrolyte leakage during molding is reduced, thereby allowing a reduction in fouling of the manufacturing equipment due to a reduction in product release from the mold with respect to particles obtained by granulation and / or a reduction in positive electrode mass variation.

In view of further improving the miscibility and formability of the positive electrode material mixture, in equation (1a), the Rsc range is preferably determined by using multiple batches of blended compositions each having a different Rm value, which is easily achieved. In the case of equation (2a) also, the Rsc range is preferably determined by using multiple batches of mixed compositions that are readily obtainable, each having a different Ra value.

Although a detailed description will be given further in the Examples below, for example, when Rsc is changed to be in the range of 0 to 27 wt.%. for multiple batches where each batch has an Rm ranging from 44.7 to 51.3 wt%, then the miscibility and formability of the positive electrode material mixture are estimated, Rsc (wt%) preferably satisfies equation ( 1) as below:

-0.0215 Rm ² + 3.1077 Rm - 92.572 <Rsc <0.0243 Rm ² - 1.2459 Rm + 22.959 (1)

Note that a batch having an Rm as above is relatively easy to obtain.

Moreover, for multiple batches, each batch having a Ra ranging from 14.2 to 20.9 wt.% As a result of changing the Rsc to fall within the range of 0 to 27 wt.%. and then estimating the miscibility and formability of the positive electrode material mixture, Rsc (wt%) preferably satisfies equation (2) as follows:

-0.0499 Ra ² + 0.7681 Ra + 8.0355 <Rsc <0.0239 Ra ² - 1.8621 Ra + 44.074 (2)

Rsc (wt%) can satisfy either or both of equation (1) and equation (2).

It should be noted that the manufacturer of dry batteries can purchase the mixed composition from the manufacturer of the materials. At present, the material manufacturer can analyze the manganese Rm ratio and / or the Ra proportion of the hydrochloric acid insoluble content, and the dry battery manufacturer can obtain the values from the analysis. These resulting values can be applied to the present invention. When batches of the mixed compositions are changed, the Rm and / or Ra values of the mixed compositions may be different. In this case, the Rsc value that has already been determined may

The variance may vary according to the variance, or it may not change as long as the above equations are satisfied for each batch.

In the first step, at least, the mixed composition and the second carbon material are mixed. However, if needed, unused manganese dioxide (second manganese dioxide) can be further admixed. When a second manganese dioxide is used, the manganese dioxide in the positive electrode includes the first manganese dioxide and the second manganese dioxide.

As the second manganese dioxide, known can be used. Examples of the second manganese dioxide include electrolytic manganese dioxide, natural manganese dioxide, and chemical manganese dioxide. The second manganese dioxide may be used singly or in combination of two or more. Electrolytic manganese dioxide may be used to improve the performance of the manganese dry battery according to the user's needs. To reduce costs, natural manganese dioxide and / or chemical manganese dioxide can be used. In view of the balance between yield and cost, these manganese dioxide can be arbitrarily mixed. The second manganese dioxide is preferably in the form of a powder.

The Rsm ratio of the second manganese dioxide when the amount of the mixed composition is 100 wt%. it can be arbitrarily selected according to the needs of the user, and, for example, can be determined in light of a balance between performance and cost. To reduce costs, it is preferable to reduce the proportion Rsm, and for example, Rsm may be 0 wt.%. To improve the yield, it is preferable to increase the proportion of Rsm, and for example, Rsm may be increased to about 90 wt%.

Mixing may be performed by known mixing methods, and for example, a known mixer and / or kneader may be used.

The mixing can be by either dry blending or wet blending, or a combination thereof. For example, the blended composition, the second carbon material, and, if desired, the second manganese dioxide, may be dry blended; and then, the electrolyte may be added to the mixture by spraying or the like, thus to further effect wet mixing. The combination of dry blending and wet blending can further increase the dispersibility of the ingredients, and a positive electrode material mixture that is more uniformly blended can be obtained.

According to the present invention, by using the second carbon material in specific amounts, the blended composition, the second carbon material, and the second manganese dioxide, if needed, can be mixed homogeneously, and the flowability of the resulting positive electrode material mixture increased. It should be noted that during mixing, the solid components (e.g., manganese dioxide, carbon material) among the components of the mixture of the positive electrode material with the electrolyte contained therein are granulated to the appropriate degree. By using the second carbon material in specific amounts, granulation becomes easier to blend, and this also allows an increase in flowability and improved formability.

The average size of the particles (granules) obtained by mixing is, for example, preferably 1 to 10 mm and more preferably 1 to 3 mm. When the mean particle size of the granules is within the above range, the components of the positive electrode material mixture can be mixed more uniformly. By obtaining a positive electrode material mixture that is homogeneously mixed, the formability of the positive electrode material mixture can also be improved.

Examples of the electrolyte include an aqueous solution containing zinc chloride. The zinc chloride content of the electrolyte is, for example, from 20 to 40% by weight.

Ammonium chloride may be added to the electrolyte in small amounts. The ammonium chloride content of the electrolyte is, for example, from 0.5 to 10% by weight. or from 1 to 10 wt.%.

The proportion Re of the electrolyte used in the first step is, for example, from 50 to 90% by weight. and preferably from 60 to 85 wt.% when the amount of the mixed composition is 100 wt.%. When the ratio Re of the electrolyte is within the above range, the flowability of the positive electrode material mixture may increase more, which is beneficial to improve formability.

In a second step, the positive electrode material mixture produced in the first step is formed to form a positive electrode.

Molding can be carried out by a known method. For example, a positive electrode material mixture may be introduced into a mold and then pressure molded to form a positive electrode. Alternatively, if needed, the positive electrode material mixture can be introduced into the negative electrode can with a separator and bottom paper

The mixture is dispersed between the mixture material and the can and then compressed if suitable to form a positive electrode.

The shape of the positive electrode can be defined according to the shape of the manganese dry battery, and is, for example, a round cylinder or a polygonal cylinder.

According to the present invention, since the flowability of the positive electrode material mixture can be improved, even with the use of materials recovered from spent batteries, the positive electrode material mixture can be easily fed to the second step and / or easily introduced into the mold. Thus, high efficiency can be maintained.

Moreover, since the electrolyte can also be properly retained in the positive electrode material mixture, adhesion of the positive electrode material mixture to the mold can also be reduced. In this case, in view of the possibility of reducing the contamination of the mold as well, the efficiency can be improved. Moreover, cracks and / or chips in the positive electrode can also be reduced. Thus, the imperfections in the quality of the positive electrode can be effectively reduced.

As above, according to the present invention, the material recovered from the spent dry batteries can be recycled into the positive electrode material for the dry manganese battery. Thus, a recycling network for dry manganese batteries can be developed, making it possible to contribute to reducing the amount of used disposable dry manganese batteries.

The method of manufacturing a manganese dry battery comprises: step A of producing a positive electrode; and step B of placing the battery components, including the positive electrode, in the negative electrode can.

In step A, a positive electrode is produced containing manganese dioxide, carbon material and electrolyte. In particular, step A comprises the first step and the second step described above. Regarding the details of step A, the details of the method for producing the positive electrode are given above.

In step B, the positive electrode obtained in step A is used to build a dry manganese battery. Specifically, in the negative electrode can, a positive electrode and a separator are inserted between the positive electrode and the negative electrode can. In the central part of the positive electrode a current collector of the positive electrode in the form of a rod (e.g. a carbon rod) is inserted parallel to the direction of the longitudinal axis of the positive electrode.

Then, the open part of the negative electrode can is sealed with a lid, which also serves as the positive pole, with an insulating gasket placed in between, thus allowing a dry manganese battery to be obtained. Note that the cover is electrically connected to the current collector of the positive electrode.

A method of producing a manganese dry battery will now be described with reference to Fig. 1. Fig. 1 is a cutaway sectional view of a size D (R20) manganese dry battery.

Initially, the cylindrical positive electrode 1 is housed in a cylindrical negative electrode 4 box closed at the bottom, with a separator 3 made in the form of a tube and a circular paper 13 at the bottom between. A columnar collector of positive electrode 2 is positioned in the hollow middle part produced in the axial central part of the positive electrode 1, and a circular paper collar 9 is used in the upper part of the positive electrode 1. A circular hole is produced in the middle part of the paper collar 9 and one end of the part the current collector of the positive electrode 2 passes through this hole so as to project upwards from the top surface of the positive electrode 1 (or from the paper collar 9). A gasket 5 having an opening in its central part is placed on the open part of the negative electrode can 4. Now, one end of the current collector part of the positive electrode 2 passes through the gasket opening 5 in a mating manner and projects from the upper face of the gasket 5.

Then, the negative pole formed by the disc-shaped tin plate is placed in the lower part (outer lower surface) of the negative electrode can 4. The peripheral edge part of the negative pole 6 has a shape similar to the brim of a hat, and the negative pole 6 is positioned so that the peripheral part is the lip is in contact with the outer bottom surface of the negative electrode can 4. Next, an adhesive ring 7 made of paraffin impregnated paper is placed on a part of the peripheral edge of the negative pole part 6.

The inner side of the negative electrode can 4 becomes covered with a heat shrinkable resin tube 8, the surface side starts with the adhesive ring 7 on the outer bottom surface of the negative electrode 4 can, up to the gasket 5 on the open part of the negative electrode 4 can. Then, the positive pole 11 is formed of a tin plate

The PL 237 725 B1 is positioned on the top of the seal 5 so that the protruding one end of the current collector portion of the positive electrode 2 becomes covered here. The positive pole 11 has a cavity including one end of the positive electrode current collector portion 2 in a central portion in contact with one end of the positive electrode current collector portion 2; and has a flat (disk-shaped) portion flange which protrudes from a peripheral edge portion of the recess. The upper part of the current collector of the positive electrode 2 is mated with the cavity of the positive pole 11, and the current collector of the positive electrode 2 and the positive pole 11 are electrically connected.

The structure obtained as above is placed in the metal can of the outer package 10 in the shape of a tube, and the insulating ring 12 is placed on the peripheral edge of the positive pole part 11. Next, the upper end of the metal can part of the outer package 10 is internally twisted. The front end of this upper end portion is attached to the positive pole 11, with an insulating ring 12 disposed therebetween, thereby forming a dry manganese battery.

The negative electrode can be made of zinc or an alloy containing zinc. The zinc alloy may, for example, be one that contains lead or the like.

As the separator and the bottom paper, for example, those known as separators or bottom papers for dry manganese batteries, such as drawing paper, to which the adhesive paste material has been applied and then dried, can be used. As the material of the adhesive paste, for example, a product containing a tackifier mainly composed of polyvinyl acetate, cross-linked starch and their aqueous solvent can be used. The adhesive paste material may be applied to one face of the drawing paper and the surface with the adhesive paste material applied may be placed against the inner surface of the negative electrode can.

The electrolyte is contained in the positive electrode, and if needed, the electrolyte can be further added in step B of the battery construction. As the electrolyte to be added in step B, it may be used, for example, from those mentioned for the electrode, and used in the mixing of the positive electrode material mixture. The electrolyte used may be one having the same composition (e.g. same components and / or the same concentration) as that used in mixing the positive electrode material mixture, or one having a different composition.

Examples

Preparation Examples 1 to 5 (1) Preparation of the blended composition

First, the spent batteries of the spent manganese dry battery and the spent alkaline dry battery were prepared, the first and the second were mixed in 5 different ratios.

Then, 5 batches (5 kinds) of mixed compositions were obtained using the method disclosed in Patent Literature 1, each containing a first manganese dioxide and a first carbon material. Further, after crushing the used dry batteries using a crushing machine, the magnetic substances (e.g. metal cans of the outer packaging, positive poles, negative poles) were separated by magnetic separation, large-sized solids (e.g. zinc cans, paper material, plastic) were removed using a sieve and then the remaining granules were collected. The collected granules were added to dilute sulfuric acid (concentration: 1.8 mol / l) and the resulting mixture was stirred at 60 ° C for about 60 minutes, thus passing the manganese dioxide and carbon material (first carbon material) to the recovery process . Then, the treated granules were collected. The collected granules were further added to dilute sulfuric acid (concentration: 1.8 mol / L), after the previous recovery operation as stated above, and the operation of collecting the granules was repeated many times. The collected granules were washed with water and then dried, thus obtaining a mixed composition.

(2) Analysis of the blended composition

The respective batch compositions of the blended compositions were analyzed using the following procedure. The results of the analysis are given in Table 1.

<Ra proportion of the content of the hydrochloric acid insoluble, proportion Rfc of the first carbon material, proportion Rm of manganese and proportion Rfm of the first manganese dioxide>

From each batch of the mixed composition, a 0.5 g sample was drawn, 20 mL of 6 mol / L hydrochloric acid was added to the sample, and then, what was obtained, was heated at 160 ° C for 1 hour. The resulting mixture was filtered through a glass filter and its insoluble content (the content insoluble in hydrochloric acid) was collected, dried at 110 ° C for 3 hours and then weighed on a balance. The proportion Ra (wt%) of the insoluble content was then calculated

PL 237 725 Β1 in hydrochloric acid in the mixed composition. Moreover, the content insoluble in hydrochloric acid was analyzed by thermogravimetric analysis (device: Q5000IR, available from TA Instruments) and a percentage weight loss was obtained in the temperature range from 400 ° C to 900 ° C, corresponding to the ratio Rf _C (wt%). the first carbon material in the mixed composition.

The remaining filtrate after separation of the hydrochloric acid insoluble content was diluted and then analyzed by ICP emission spectroscopy analysis (device: iCAP6300, available from Thermo Fisher Scientific), thus obtaining the proportion R _m (wt%) of manganese in the blended composition.

From the ratio between the manganese atomic weight (54.94) and the manganese dioxide molecular weight (86.94), the ratio R _m manganese to the ratio R f m (wt%) of the first manganese dioxide in the blended composition was converted.

Table 1

Proportion Ra proportion for Proportion Proportion Rfm first un- Rf _C first Rm man- his permissible in my mother Other Party ganu dioxide chlorine acid material manganese cod carbon (wt%) (wt%) (wt%) (wt%) (S. wt. ) 1 44.7 70.7 20.9 17, 6 10.8 2 45, 4 71.8 20.0 17.2 10.2 3 47, 5 75, 2 17.5 15.0 8, 9 4 48, 9 77.4 15, 8 13.4 8, 3 5 51, 3 81.2 14.2 12, 6 5, 4

As shown in Table 1, in the mixed compositions of all batches, the weight ratio of the first manganese dioxide to the first carbon material ranges from 4: 1 to 6.4: 1. This weight ratio is in the range of the weight ratio of manganese dioxide to carbon material in the positive electrode for typical manganese dry batteries.

Reference Example 1

The positive electrode material mixture was prepared by using unused manganese dioxide and unused carbon material using the following procedure.

Specifically, unused manganese dioxide and unused carbon material were introduced into a 15 L drum rotary mixer and mixed (dry blended) at 20 rpm for 5 minutes. Thereafter, it was stirred at 15 rpm while the predetermined amount of electrolyte was sprayed here for 5 minutes. In addition, mixing (wet mixing) was performed at 20 rpm for 1 minute, thus obtaining positive electrode material mixtures (R-1). As the electrolyte, an aqueous solution containing 1 wt. % ammonium chloride and 30 wt. zinc chloride.

Note that the weight ratio of unused manganese dioxide to unused carbon material was 5: 1, being the average weight ratio of the first manganese dioxide to the first carbon material for the mixed compositions of Preparation Examples 1 to 5. The total amount of manganese dioxide and carbon material was 1500 g. and 1250 g of electrolyte was used to achieve homogeneous mixing.

Comparative Examples 1 to 5

By using the mixed compositions obtained in Preparation Examples 1 to 5, mixtures of the positive electrode material for the manganese dry battery were suitably prepared.

Further, except for the use of the blended compositions obtained in Production Examples 1 to 5 in place of unused manganese dioxide and unused carbon material,

PL 237 725 Β1 mixtures of positive electrode material (Tr-1) to (Tr-5) were prepared as in Reference Example 1.

Assessment of miscibility

The states of the positive electrode material mixtures obtained in Reference Example 1 and Comparative Examples 1 to 5 were assessed on the basis of the following criteria serving as an index for miscibility.

A: Satisfactory. Granulation was possible and resulted in an average particle size of 1 to 3 mm.

B: Granulation was possible but as a result the mean particle size was over 3mm and is 10mm or less.

C1: As a result, large lumps were obtained with an average particle size of 10 mm or greater.

C2: Granulation was not possible and the obtained state was close to the original powder form.

C3: Granulation was not possible and the obtained state was not fluid due to the excessive water content.

Note that C1 to C3 are levels at which formation of a positive electrode, ie the next step, is not possible.

The evaluation of the results for the positive electrode material mixtures of Reference Example 1 and Comparative Examples 1 to 5 is given in Table 2. In Table 2, the respective positive electrode material mixture compositions are also given.

Table 2

Positive electrode material mixture A batch of mixed composition Weight of mixed composition (g) Mass of unused manganese dioxide Mass of unused carbon material (g) Electrolyte weight (g) I have madness R-1 - - 1250 250 1250 AND Tr-1 1 1500 - - Cl Tr-2 2 1500 - - Cl Tr-3 3 1500 - - C2 Tr-4 4 1500 - - C3 Tr-5 5 1500 - - C3

As shown in Table 2, regarding the mixture of positive electrode material R-1 of Reference Example, using unused manganese dioxide and unused carbon material, satisfactory granulation was possible, giving the correct particle size; and the ingredients were homogeneously mixed. In contrast, for all the positive electrode material mixtures Tr-1 to Tr-5 that were used, the granulation of the mixed compositions recovered from spent dry batteries, respectively, was inferior and uniform mixing was not possible. Moreover, depending on the batch, the evaluation of the results varied greatly from C1 to C3 and the condition (or properties) of the positive electrode material mixtures was very different from one another.

Reference Examples 2 to 6 (1) Preparation of the positive electrode material mixture and formation of the positive electrode.

By using the blended compositions obtained in Preparation Examples 1 to 5, suitably mixtures of the positive electrode material for the manganese dry battery were prepared. Further, except for using the blended compositions obtained in Preparation Examples 1 to 5, instead of unused manganese dioxide and unused carbon material, and for changing the electrolyte ratio as shown in Table 3, positive electrode material mixtures were prepared as in Reference Example 1.

The resulting positive electrode material mixtures were suitably introduced into the mold, compressed as appropriate, and formed into positive electrodes in a cylindrical mold.

(2) Assessment

By using the obtained positive electrode material mixtures, the miscibility was assessed in a similar manner as above.

The states of the obtained positive electrode material mixtures during forming and the states of the obtained positive electrodes were assessed on the basis of the following criteria serving as the formability index.

a: Satisfactory. Molding was possible in the right way.

b: Cracks and flakes were observed in the positive electrode that was formed.

c: Pressure during forming caused the electrolyte to leak, resulting in fouling of the manufacturing equipment and / or visible weight differences in the positive electrode. The results are given in Table 3.

Table 3

Positive electrode material mixture A batch of mixed composition Electrolyte weight (g) Mix- nity Forming- nity R-2-1 1 1375 C2 - R-2-2 1250 Cl - R-2-3 1125 B c R-2-4 1000 AND b R-3-1 2 1375 C2 - R-3-2 1250 Cl - R-3-3 1125 B G. R-3-4 1000 AND b R-4-1 3 1375 C3 - R-4-2 1250 C2 - R-4-3 1125 B c R-4-4 1000 AND b R-5-1 4 1375 C3 - R-5-2 1250 C3 - R-5-3 1125 Cl - R-5-4 1000 B c R-6-1 5 1375 C3 - R-6-2 1250 C3 R-6-3 1125 C2 - R-6-4 1000 Cl -

PL 237 725 Β1

As shown in Table 3, when mixed compositions recovered from spent dry batteries were used, depending on the batch, there were cases where the miscibility was improved by reducing the electrolyte ratio. However, such a reduction in the electrolyte ratio reduced the efficiency of the positive electrode (especially the discharge efficiency of the battery) and the practicality of the positive electrode was lowered. Moreover, even using mixtures of positive electrode material having improved miscibility, the formability was low.

Moreover, depending on the batch of the blended composition, even with the adjustment of the electrolyte ratio of the manganese dry battery, there were cases where homogeneous mixing was not possible.

As can be seen from the results in Tables 2 and 3, even using the mixed composition recovered from the spent dry manganese battery and the spent dry alkaline battery as the positive electrode material for the manganese dry battery, it was difficult to obtain a workable positive electrode and a workable dry manganese battery.

Examples 1to5

By using the mixed compositions (batches 1 to 5) obtained in Preparation Examples 1 to 5 and unused carbon material (second carbon material), mixtures of positive electrode material for the manganese dry battery were respectively prepared.

Further, in addition to 1500 g of the respective blended compositions, a second carbon material was used in the amounts shown in Table 4. Except above, positive electrode material mixtures were prepared as in Comparative Examples 1 to 5. Acetylene carbon black (available from Denki) was used as the second carbon material (available from Denki). Kagaku Kogyo KK, purity: Denka carbon black 50% compressed); and this carbon material was added to the mixer along with the respective blended compositions. 1250 g of electrolyte was used to prepare the respective mixtures of the positive electrode material.

The respective obtained positive electrode material mixtures were introduced into the mold, compressed as appropriate, and formed into positive electrodes in a cylindrical form.

Appropriate positive electrode material mixtures obtained were used to determine miscibility, as was done with those of Comparative Examples 1 to 5.

The states of the positive electrode material mixtures during molding and the states of the obtained positive electrodes were assessed as in Reference Examples 2 to 6.

The results are given in Table 4. Table 4 also shows the results for the cases where the amount of electrolyte was 1250 g in Table 3.

Table 4

Mixes- nina ma- material positive electrode A lot of mixed parties Weight of the second carbon material (g) Proportion Rsc dru- second carbon material (wt.%) Mix- nity Formo- valor R-2-2 1 0 0 Cl - Prov-1-1 45.0 thirty AND c

PL 237 725 Β1

Prov-1-2 60.0 4.0 AND and Prov-1-3 135.0 9.0 AND and Prov-1-4 225.0 15.0 AND and Prov-1-5 240.0 16, 0 AND b Prov-1-6 270.0 18.0 B b R-3-2 2 0 0 Cl - Prov-2-1 60.0 4.0 AND c Prov-2-2 67, 5 4.5 AND and Prov-2-3 150.0 10, 0 AND and Prov-2-4 240.0 16.0 AND and Prov-2-5 255.0 17.0 AND b Prov-2-6 285.0 19.0 B b R-4-2 3 0 0 C2 - Prov-3-1 90.0 6, 0 AND c Prov-3-2 105.0 7.0 AND and Prov-3-3 180.0 12.0 AND and Prov-3-4 270.0 18.0 AND and Prov-3-5 285.0 19.0 AND b Prov-3-6 315.0 21.0 B b R-5-2 4 0 0 C3 - Prov-4-1 105.0 7.0 AND c Prov-4-2 120.0 8.0 AND and Prov-4-3 210.0 14.0 AND and Prov-4-4 300.0 20, 0 AND and Prov-4-5 330.0 22, 0 AND b Prov-4-6 375.0 25.0 B b R-6-2 5 0 0 C3 - Prov-5-1 150.0 10.0 AND c Prov-5-2 165.0 11, 0 AND and Prov-5-3 240.0 16, 0 AND and Prov-5-4 330.0 22.0 AND and Prov-6-5 360.0 24.0 AND b Prov-7-6 405.0 27.0 B b

PL 237 725 Β1

As shown in Table 4, it is evident that by adding the second carbon material in a predetermined amount, the granulation of the positive electrode material mixture is improved and the mixing thereof was made more homogeneous. When the positive electrode material mixtures of the Reference Examples were used, the formation of a positive electrode was not possible. However, on the contrary, the positive electrode material mixtures of the Examples were formed into a positive electrode, and the formability was also satisfactory.

Example 6

In the present Examples, in view of the miscibility and formability, the relationship between the proportion R _sc (wt%) of the second carbon material and the proportion R _m (wt%) of the manganese in the blended composition was checked.

Further, first, for each batch used in Examples 1 to 5, the upper limit values and the lower limit R _sc values of the second carbon material rated as "A" for miscibility and "a" for formability were collected. These high limit values and low limit values together with the R _m manganese ratio for each batch are given in Table 5.

Table 5

A batch of mixed composition Proportion Manganese rm (¾ wt.) _{R sc} proportion of the second carbon material for satisfactory miscibility and formability (wt%) Value lower bound Upper bound value 1 44.7 4.0 15.0 2 45, 4 4.5 16.0 3 47.5 7.0 18.0 4 48.9 8.0 20.0 5 51.3 11.0 22.0

The upper limit and lower limit values of R _sc shown in Table 5 are plotted as a function of R _m . Fig. 2 is a graph showing the relationship between an R _m manganese ratio and an R _sc ratio of a second carbon material. In Fig. 2, upper bound values are shown as black triangles and lower bound values are shown as black circles.

Then, linear regressions were performed for the upper bound value and the lower bound value, respectively. As a result, as shown in Fig. 2, linear regressions were obtained: Ui line and Li line showing a high correlation of the high limit value and the low limit value R _sc , respectively, with respect to Rm.

It should be noted that in this specification, regression analysis was performed using the "Microsoft Office Excel" software sheet available from Microsoft Corporation.

The linear regression equation (2-1) of the Ui line obtained by regression analysis and the linear regression equation (3-1) of the Li line obtained in the same way are as below:

Ui line: Rsc = 1.0666 R _m -32.529 (2-1) Li line: Rsc = 1.0576 R _m -43.397 (3-1)

PL 237 725 B1

As shown in Fig. 2, since the compositions exhibiting excellent miscibility and formability were present on the top of the Ui line and the bottom of the Li line as well, the 95% confidence interval at the top of the Ui line and the 95% confidence interval at the bottom of the Li line were received.

For each linear regression line, the 95% confidence interval was obtained using the Rm ± tx S equation. Here, Rm is the manganese ratio obtained from each linear regression equation, and t is the t value (= 3.182) for the 5% confidence level in the tz distribution of 3 degrees of freedom. S is the standard deviation and is expressed as [Ve x {(i / n) + (X + Y)}] ^1/2 . Here, Ve is the error variance, n is the number of data, X is the square of the deviation value in Rm, and Y is the sum of the squared error value for all data for Rsc.

Further, on the top of the line Ui, Ve = 0.0750, n = 5, X = (Rm - 47.56) ² , and Y = 28.63; and on the lower part of the line Li, Ve = 0.05905, n = 5, X = (Rm - 47.56) ² , and Y = 28.63.

Therefore, the 95% confidence interval on the upper part of the Ui line could be expressed by equation (4-1), and the 95% confidence interval interval on the lower part of the Li line could be expressed by the equation (5-i).

Rsc = 0.0243 Rm ² - i, 2459 Rm + 22.959 (4th)

Rsc = -0.02i5 Rm ² + 3, i077 Rm - 92.572 (5-i)

In Fig. 2, these 95% confidence intervals are expressed by the Ui curve and the Li curve, respectively.

From Fig. 2 it can be seen that the upper limit values giving satisfactory miscibility and formability are placed on the side below the Ui curve, the lower limit values giving the same are placed above the Li curve. Thus, it is proved that in the region between the 95% confidence interval on the upper side of the linear regression line of the upper limit and the 95% confidence interval on the lower side of the linear regression line of the lower limit value, the miscibility and formability were satisfactory and high yields were obtained. Further in Fig. 2, this area is between the Ui curve and the Li curve. Which means, in view of guaranteeing both miscibility and high formability, the second carbon material is preferably used in a proportion that satisfies equation (2).

Moreover, in view of the possibility of achieving high levels of miscibility and formability on average, the area between the high limit linear regression line and the low limit linear regression line is advantageous. Especially with reference to Fig. 2, a second carbon material may be used which allows the above region to be between the Ui line and the Li line.

If necessary, the second carbon material may be used so that the above area falls between the (lower bound) 95% confidence interval at the bottom of the linear regression line of the upper bound value and (upper bound) the 95% confidence interval at the upper end. linear regression line of lower bound values.

It should be noted that the present Examples disclosed examples of obtaining, advancing, the manganese content in the blended composition. Alternatively, it is possible to obtain the content of the first carbon material and designate the corresponding area as correlation, which is analyzed as the area described above. However, considering the difficulties of analyzing the composition of the blended composition, it is preferable to use a simple and accurate method to obtain the manganese content.

By focusing attention on the proportion of Rm of manganese in the blended composition, the blended composition can be efficiently recycled, high levels of miscibility and formability can be obtained, and difficulties in the manufacturing process can be reduced.

P r z k ł a d 7

In this Example, in view of the miscibility and formability, the relationship between the proportion Rsc (wt%) of the second carbon material and the proportion Ra (wt%) of the hydrochloric acid insoluble content of the blended composition is checked.

Further, first, for each batch used in Examples 1 to 5, the upper limit value and the lower limit Rsc value of the second carbon material rated as "A" for miscibility and "a" for formability were collected. These high limit values and low limit values are given in Table 6, together with the proportion of Ra of the hydrochloric acid insoluble content for each batch.

PL 237 725 Β1

Table 6

A batch of mixed composition Proportion R _{d of the} content insoluble in hydrochloric acid by weight) _{R S} c proportion of the second carbon material capable of satisfactory miscibility and weight formability) Value lower bound Upper bound value 1 20, 9 4.0 15.0 2 twenty 4.5 16.0 3 17.5 7.0 18.0 4 15, Θ 8.0 20.0 5 14.2 11.0 22.0

The upper limit and lower limit values of R _sc shown in Table 6 were plotted against R _a . Fig. 3 is a graph showing the relationship between a ratio R _and the hydrochloric acid insoluble content and the ratio R _{sc of a} second carbon material. In Fig. 3, upper bound values are marked with black triangles and lower bound values are marked with black circles.

Then, linear regressions were performed for the upper limit value and the lower limit value, respectively. As a result, as shown in Fig. 3, a linear regression was obtained: U2 line and line L2 showing a high correlation with the upper limit values and lower limit values Rsc, respectively, with respect to R _a.

The linear regression equation (2-2) of the U2 line was obtained by regression analysis and the linear regression equation (3-2) of the L2 line was obtained as follows:

line U ₂ : Rsc = -1.0176 R _a + 36.191 (2-2) line L ₂ : Rsc = -0.9947 R _a + 24.485 (3-2)

As shown in Fig. 3, since the compositions exhibiting excellent miscibility and formability were present on the top of the U2 line and the bottom of the L2 line as well, the 95% confidence interval at the top of the U2 line and the 95% confidence interval at the bottom of the L2 line were further received.

For each linear regression line, the 95% confidence interval interval was obtained using the equation R _a ± txS. Here, _Ra is the ratio of the content of insoluble in hydrochloric acid, obtained from each equation of linear regression, ati S were the same as those in Example 6. However, with respect to standard deviation S, X was a square of the deviation R _a.

Especially, at the top of the line U2, Ve = 0.0861, n = 5, X = (R _a - 17.68) ² and Y = 31.43; and on the lower part of the line L ₂ , Ve = 0.3690, n = 5, X = (Ra - 17.68) ² and Y = 31.43.

From the above, the 95% confidence interval at the top of line U2 can be expressed by equation (4-2), and the 95% confidence interval at the bottom of line L2 can be expressed by equation (5-2).

Rsc = 0.0239 R _a ² - 1.8621 R _a + 44.074 (4-2)

Rsc = -0.0499 R _a ² + 0.7681 R _a + 8.0355 (5-2)

In Fig. 3, these 95% confidence intervals are expressed by the U2 curve and the L2 curve, respectively.

It is clear from Fig. 3 that the upper limit values giving satisfactory miscibility and formability are located on the side below the U2 curve, and the lower limit values giving the same are

PL 237 725 B1 placed on the page above curve L2. Thus, it is clear that in the region between the 95% confidence interval at the top of the upper bound linear regression line and the 95% confidence interval at the bottom of the lower bound linear regression line, the miscibility and formability were satisfactory and high yield was obtained. Especially in Fig. 3, this area is between the U2 curve and the L2 curve. Thus, in view of guaranteeing both miscibility and high formability, the second carbon material is preferably used in a proportion that satisfies equation (3).

Further, in view of providing statistically high levels of miscibility and formability, the area between the high-limit linear regression line and the low-limit linear regression line is preferred. Especially with reference to Fig. 3, a second carbon material may be used such that the above region is between the line U2 and the line L2.

If necessary, the second carbon material may be used so that the above area is between the (lower bound) 95% confidence interval at the lower end of the linear regression line of the upper bound value and (upper bound) the 95% confidence interval at the upper end. linear regression line of lower bound values.

In these Examples, examples are disclosed for the preparation, in advance, of hydrochloric acid insoluble content in the blended composition. Alternatively, it is possible to obtain the content of the first carbon material and designate the corresponding area as the correlation, which is analyzed in the area described above. However, considering the difficulties of analyzing the composition of the mixed composition, it is advantageous to use a simple and accurate method for obtaining the hydrochloric acid insoluble content, such a method does not require the use of expensive analytical equipment.

By focusing attention on the proportion of Ra insoluble in hydrochloric acid in the blended composition, the blended composition can be efficiently recycled, high levels of miscibility and formability are obtained, and process difficulties can be reduced.

Industrial use

The materials recovered from the spent dry manganese battery and / or the spent dry alkaline battery can be recycled into the positive electrode material for the dry manganese battery in an easy way. Thus, it is possible to establish a recycling network and it is possible to reduce the amount of disposable dry manganese batteries used; and also, reducing the production cost of dry manganese batteries.

Explanation of numerical references positive electrode positive current collector electrode separator negative electrode box seal negative pole adhesive ring resin tube paper flange metal tin outer wrapped positive pole insulating ring bottom paper

Claims (5)

1. A method of producing a positive electrode for a dry manganese battery, the positive electrode comprises manganese dioxide, carbon material and electrolyte, the manganese dioxide comprises a first manganese dioxide recovered from at least one spent manganese dry battery and a spent alkaline dry battery, the carbon material comprises the first material carbon recovered with the first Manganese dioxide and an unused second carbon material, the method comprising: a first step of producing a positive electrode material mixture by mixing a mixed composition comprising a first manganese dioxide and a first carbon material, a second carbon material, and an electrolyte; and a second step of forming a positive electrode material mixture wherein the Rsc ratio of the second carbon material when the mixed composition amount is 100 wt% is 1 wt%. or more, characterized in that the process meets at least one of the following conditions (a1), (a2) and (a3): (a1) when the proportion of manganese in the blended composition is Rm and wt%, the proportion Rsc of the second carbon material in% wt.%, the amount of mixed composition is 100 wt.%, satisfies equation (1): -0.0215 Rm ² + 3.1077 Rm - 92.572 <Rsc <0.0243 Rm ² - 1.2459 Rm + 22.959; (a2) when the proportion of hydrochloric acid insoluble in the blended composition is Ra and wt%, the Rsc proportion of the second carbon material in wt%, the amount of the mixed composition is 100 wt%, satisfies equation (2): -0.0499 Ra ² + 0.7681 Ra + 8.0355 <Rsc <0.0239 Ra ² - 1.8621 Ra + 44.074, and the content insoluble in hydrochloric acid is the residue resulting from the heat treatment of the mixed composition in hydrochloric acid with a concentration of 6 mol / l; and (a3) the manganese dioxide additionally comprises unused second manganese dioxide, and in the first step, the mixed composition, the second manganese dioxide and the second carbon material are mixed. 2. A method for producing a positive electrode for a manganese dry battery according to claim 1; The process of claim 1, wherein the Rfc proportion of the first carbon material in the blended composition is 6 to 30 wt%. 3. The method of producing a positive electrode for a manganese dry battery according to claim 1; The method of claim 1 or 2, characterized in that the proportion Rsc of the second carbonate material is 2 to 30 wt.%. 4. The method of producing a positive electrode for a manganese dry battery according to claim 1; A process according to claim 1 or 2, characterized in that the mixed composition is obtained by carrying out: a process of crushing the electrode that was contained in at least one spent dry manganese battery and a spent dry alkaline battery to obtain granules, and a process of treating the granules with a dilute acid comprising at least one of hydrochloric acid and sulfuric acid. 5. The method of producing a positive electrode for a manganese dry battery according to claim 1; The process of claim 1 or 2, wherein the second manganese dioxide is at least one selected from the group consisting of electrolytic manganese dioxide, natural manganese dioxide, and chemical manganese dioxide.