Positive electrode mixing method of lithium-manganese primary battery, prepared positive electrode mixture and application of positive electrode mixture

Abstract

The invention belongs to the technical field of batteries, and provides a positive electrode mixing method of a lithium-manganese primary battery, a prepared positive electrode mixture and application of the positive electrode mixture, the positive electrode mixing method comprises the following steps: carrying out first mixing on a conductive agent and beta-Al2O3 to obtain a modified conductive agent; and carrying out second mixing on the modified conductive agent, the positive electrode active material and the binder to obtain a positive electrode mixture. The beta-Al2O3 is used for promoting dispersion of the conductive agent, the high specific surface area and the porous structure of the beta-Al2O3 are beneficial to adsorption and fixation of conductive agent particles and prevention of aggregation of the conductive agent particles, meanwhile, the beta-Al2O3 has good compatibility with components in other battery positive electrodes, no additional chemical reaction or side effect is introduced, the dispersion uniformity of the conductive agent can be more effectively improved, and the conductivity of the battery positive electrode is improved. And the battery performance is improved.

Description

Technical Field

[0001] This invention belongs to the field of battery technology and relates to a method for mixing positive electrode materials for lithium manganese primary batteries, the obtained positive electrode mixture, and its uses. Background Technology

[0002] Lithium-manganese dioxide primary batteries are widely used in consumer electronics, smart meters, and medical devices due to their high voltage, high specific energy, and excellent storage performance. In this battery system, the positive electrode is typically composed of manganese dioxide active material, a conductive agent, and a binder, with the uniform distribution of the conductive agent having a decisive influence on battery performance.

[0003] Compared to other battery systems, the manganese dioxide material used in lithium-manganese batteries is typically chemically produced or electrolytically produced manganese dioxide. Its crystal structure has a high defect density, and after pulverization, the particle size is small, resulting in a large specific surface area and high surface energy. This leads to enhanced van der Waals forces and electrostatic interactions between particles, making it prone to agglomeration. Simultaneously, its surface is rich in active groups such as hydroxyl groups, exhibiting strong hydrophilicity and readily adsorbing moisture from the environment. This can not only trigger electrolyte decomposition but also alter the particle surface properties, affecting interfacial compatibility with conductive agents. Furthermore, the semiconductor properties of manganese dioxide result in low intrinsic electronic conductivity, necessitating the construction of an effective electron transport network using conductive agents. Commonly used conductive agents, such as acetylene black, carbon black, graphite, or carbon nanomaterials, need to form a continuous and uniform conductive pathway within the limited positive electrode space to ensure the active material fully participates in the electrochemical reaction.

[0004] However, achieving uniform dispersion of conductive agents within a manganese dioxide matrix presents a significant challenge. Uneven distribution of the conductive agent can lead to insufficient electronic conductivity in localized areas, creating "dead zones" that prevent some manganese dioxide from effectively participating in the discharge reaction, reducing the utilization rate of active materials and consequently decreasing the actual battery capacity. Simultaneously, discontinuities in the conductive network exacerbate electrode polarization, causing a decrease in the discharge voltage plateau, particularly under medium- to high-rate discharge conditions. More seriously, areas rich in conductive agents may generate concentrated currents during discharge, triggering localized overheating and increasing the risk of thermal runaway; while areas lacking conductive agents may experience stress concentration due to uneven reaction, accelerating electrode structure degradation and impacting battery safety and cycle stability.

[0005] Currently, industrial processes primarily employ physical methods such as mechanical mixing, high-speed stirring, or ball milling to promote the dispersion of conductive agents. Some processes also introduce surfactants or dispersants to reduce the tendency for particle agglomeration. However, residual surfactants and dispersants may affect electrolyte stability or increase the risk of side reactions. Therefore, achieving efficient, stable, and uniform dispersion of conductive agents in a high specific surface area, highly active manganese dioxide matrix without introducing harmful impurities or affecting the integrity of the electrode structure remains a key technical challenge for improving the performance and reliability of lithium-manganese dioxide primary batteries. Summary of the Invention

[0006] In view of the problems existing in the prior art, the purpose of this invention is to provide a method for mixing the positive electrode of a lithium manganese primary battery, the obtained positive electrode mixture, and its uses. The positive electrode mixing method includes a first mixing of a conductive agent with β-Al₂O₃ to obtain a modified conductive agent; and a second mixing of the modified conductive agent with a positive electrode active material and a binder to obtain the positive electrode mixture. This invention utilizes β-Al₂O₃ to promote the dispersion of the conductive agent. The high specific surface area and porous structure of β-Al₂O₃ help adsorb and fix the conductive agent particles, preventing their aggregation. At the same time, β-Al₂O₃ has good compatibility with other components in the positive electrode of the battery, and will not introduce additional chemical reactions or side effects, thus more effectively improving the dispersion uniformity of the conductive agent and thereby improving battery performance.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0009] The conductive agent is first mixed with β-Al2O3 to obtain a modified conductive agent; then the modified conductive agent is second mixed with a positive electrode active material and a binder, wherein the positive electrode active material includes manganese dioxide, to obtain a positive electrode mixture.

[0010] In this invention, β-Al₂O₃ possesses a high specific surface area and abundant porous structure, enabling it to effectively adsorb conductive agent particles through van der Waals forces and other interactions, preventing their aggregation during mixing. Simultaneously, the hydroxyl groups (-OH) or other functional groups on the surface of β-Al₂O₃ can interact with the groups on the surface of the conductive agent, further enhancing the binding force. Moreover, β-Al₂O₃ exhibits good thermal and chemical stability under battery operating conditions. Furthermore, β-Al₂O₃ shows good compatibility with other components in the battery cathode, without introducing additional chemical reactions or side effects, and can more effectively improve the dispersion uniformity of the conductive agent, thereby enhancing battery performance.

[0011] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The technical objectives and beneficial effects of the present invention can be better achieved and realized through the following technical solutions.

[0012] As a preferred technical solution of the present invention, the β-Al2O3 includes gas-phase nano-β-Al2O3 with a hexagonal crystal system and a purity ≥98%, such as 98%, 98.5%, 99%, 99.2%, etc.

[0013] Preferably, the particle size (D50) of the β-Al2O3 is 50 nm to 100 nm. Exemplarily, it can be 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, or 100 nm, etc.

[0014] Preferably, the specific surface area of ​​the β-Al₂O₃ is 80 m². 2 / g~100m 2 / g, for example, could be 80m 2 / g、85m 2 / g、90m 2 / g、95m 2 / g or 100m 2 / g etc.

[0015] In this invention, β-Al2O3 has a suitable particle size D50, which is beneficial for having a high specific surface area and good adsorption capacity. If the particle size is too large, it will affect its adsorption of conductive agents and its dispersion effect.

[0016] As a preferred embodiment of the present invention, the β-Al2O3 accounts for 1% to 3% of the total mass of the conductive agent, β-Al2O3, positive electrode active material and binder, calculated as 100%. For example, it can be 1%, 1.6%, 2%, 2.4%, 2.8% or 3%, etc.

[0017] In this invention, β-Al2O3 should be used in an appropriate amount. Too little β-Al2O3 will result in insufficient adsorption of the conductive agent, which will not effectively fix the conductive agent and will affect the dispersion effect.

[0018] And / or, the mass percentage of the positive electrode active material is 85% to 91%. For example, it can be 85%, 86%, 87%, 88%, 89%, 90%, or 91%, etc.

[0019] And / or, the conductive agent accounts for 6% to 8% of the mass. For example, it can be 6%, 6.6%, 7%, 7.6%, or 8%, etc.

[0020] And / or, the adhesive accounts for 2% to 4% of the total mass. For example, it can be 2%, 2.6%, 3%, 3.2%, 3.4%, or 4%, etc.

[0021] As a preferred embodiment of the present invention, the conductive agent includes at least one of graphite, conductive carbon black, acetylene black, graphene, or carbon nanotubes.

[0022] Preferably, the adhesive comprises at least one of polytetrafluoroethylene, styrene-butadiene rubber, ethylene-acrylic acid copolymer, or polyvinylidene fluoride and its modifiers.

[0023] As a preferred technical solution of the present invention, the first mixing includes solid-phase mixing.

[0024] Preferably, the solid-phase mixing includes ball milling.

[0025] Preferably, the ball milling time is 1 hour to 3 hours. For example, it can be 1 hour, 1.6 hours, 2 hours, 2.6 hours, or 3 hours.

[0026] As a preferred technical solution of the present invention, the second mixing includes a semi-dry process.

[0027] Preferably, the semi-dry process includes mixing and granulating a modified conductive agent, a positive electrode active material, and a binder (and / or other granulating agent), followed by baking, to obtain a positive electrode mixture.

[0028] Preferably, the baking temperature is 110℃~130℃, such as 110℃, 120℃, 125℃ or 130℃, and the baking time is 0.5h~2h, such as 0.5h, 1h, 1.6h or 2h.

[0029] Secondly, the present invention provides a positive electrode mixture obtained using the positive electrode mixing method described in the first aspect.

[0030] Thirdly, the present invention provides a positive electrode sheet, which is made using the positive electrode mixture described in the second aspect.

[0031] For example, a method for preparing the positive electrode sheet includes compressing the positive electrode mixture in a molding die.

[0032] It should be noted that the positive electrode includes a positive current collector and a positive active layer disposed on the positive current collector.

[0033] Preferably, the positive electrode current collector includes a current collector ring or a current collector mesh. In lithium manganese coin cells, a positive electrode ring is generally used as the current collector, while in cylindrical cells, a steel mesh or aluminum mesh is used.

[0034] Fourthly, the present invention provides a lithium manganese primary battery comprising the positive electrode sheet described in the third aspect.

[0035] It should be noted that, by way of example, the lithium manganese primary battery includes, in addition to the positive electrode, a negative electrode, a separator, and an electrolyte.

[0036] Preferably, the negative electrode comprises pure metallic lithium or a lithium alloy.

[0037] Preferably, the doped metal element in the lithium alloy includes at least one of aluminum, magnesium, or calcium; based on the total mass of the negative electrode sheet as 100%, the mass percentage of the doped metal element is 0.05% to 3%, for example, 0.05%, 0.1%, 0.5%, 1%, 2%, or 3%.

[0038] Preferably, the diaphragm comprises polypropylene (PP) and polyethylene (PE).

[0039] Preferably, the electrolyte comprises a lithium salt and a non-aqueous solvent; the lithium salt comprises at least one of LiClO4, LiFSI, LiBOB or LiTFSI; the non-aqueous solvent comprises at least one of ethylene carbonate, butyl carbonate, diethyl carbonate, methyl ethyl carbonate, 1,2-dimethoxyethane or 1,2-diethoxyethane.

[0040] Preferably, as a preferred technical solution of the present invention, the electrolyte injection volume is 1.2g / Ah to 1.5g / Ah, such as 1.2g / Ah, 11.3g / Ah, 1.4g / Ah or 1.5g / Ah.

[0041] Preferably, the lithium manganese primary battery includes any one of button cells, cylindrical cells, or pouch cells.

[0042] Fifthly, the present invention provides an electrical device comprising the lithium manganese primary battery described in the fourth aspect.

[0043] As a further example, the electrical devices include those applicable to smart meters and remote monitoring systems, such as water meters, electricity meters, gas meters, and heat meters; they can also be used in the field of medical electronic devices, such as implantable medical devices like pacemakers, nerve stimulators, implantable defibrillators, portable medical testing instruments, blood glucose meters, or electronic thermometers; and they can also be used in consumer electronics products such as backup power supplies for Internet of Things (IoT) and wireless sensor networks or CMOS memory on computer motherboards, cameras, electronic door locks, remote controls, electronic tags (RFID), and small electronic toys.

[0044] It should be noted that, due to space limitations and to avoid redundancy, this invention does not exhaustively list all point values ​​within the above numerical range, but it is not limited to the listed values ​​either; other unlisted values ​​within the above numerical range are also applicable.

[0045] Compared with existing technical solutions, the present invention has at least the following beneficial effects:

[0046] The positive electrode mixing method for lithium-manganese primary batteries described in this invention uses β-Al₂O₃, which has a high specific surface area and abundant porous structure. This allows it to effectively adsorb conductive agent particles through van der Waals forces and other interactions, preventing their aggregation during mixing. Simultaneously, the hydroxyl (-OH) groups or other functional groups on the surface of β-Al₂O₃ can interact with the groups on the surface of the conductive agent, further enhancing the binding force. Moreover, β-Al₂O₃ exhibits good thermal and chemical stability under battery operating conditions. Furthermore, β-Al₂O₃ has good compatibility with other components in the battery positive electrode, without introducing additional chemical reactions or side effects, and can more effectively improve the dispersion uniformity of the conductive agent, thereby enhancing battery performance. Detailed Implementation

[0047] The technical solution of the present invention will be further illustrated below through specific embodiments.

[0048] Those skilled in the art will understand that the embodiments described are merely illustrative of the invention and should not be construed as limiting the invention.

[0049] Example 1

[0050] This embodiment provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0051] The invention provides conductive agent graphite and hexagonal crystal structure gas phase nano β-Al2O3, wherein the particle size D50 of the β-Al2O3 is 50 nm. The conductive agent and β-Al2O3 are first mixed at a mass ratio of 7:2. The first mixing is carried out by ball milling for 2 hours to obtain the modified conductive agent.

[0052] Then, the modified conductive agent, the positive electrode active material manganese dioxide, and the binder polyvinylidene fluoride are mixed and granulated according to a mass ratio of 9:88:3, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0053] Example 2

[0054] This embodiment provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0055] The invention provides conductive agent graphite and hexagonal crystalline structure fumed nano β-Al2O3, wherein the average particle size (D50) of the β-Al2O3 is 50 nm. The conductive agent and β-Al2O3 are first mixed at a mass ratio of 8.5:0.5, and the first mixing is performed by ball milling for 2 hours to obtain the modified conductive agent.

[0056] Then, the modified conductive agent, the positive electrode active material manganese dioxide, and the binder polyvinylidene fluoride are mixed and granulated according to a mass ratio of 9:88:3, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0057] Example 3

[0058] This embodiment provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0059] The invention provides conductive agent graphite and hexagonal crystal structure gas phase nano β-Al2O3, wherein the particle size D50 of the β-Al2O3 is 50 nm. The conductive agent and β-Al2O3 are first mixed at a mass ratio of 8:1. The first mixing is carried out by ball milling for 2 hours to obtain the modified conductive agent.

[0060] Then, the modified conductive agent, the positive electrode active material manganese dioxide, and the binder polyvinylidene fluoride are mixed and granulated according to a mass ratio of 9:88:3, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0061] Example 4

[0062] This embodiment provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0063] The invention provides conductive agent graphite and hexagonal crystal structure gas phase nano β-Al2O3, wherein the particle size D50 of the β-Al2O3 is 50 nm. The conductive agent and β-Al2O3 are first mixed at a mass ratio of 7:3. The first mixing is carried out by ball milling for 2 hours to obtain the modified conductive agent.

[0064] Then, the modified conductive agent, the positive electrode active material manganese dioxide, and the binder polyvinylidene fluoride are mixed and granulated according to a mass ratio of 9:88:3, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0065] Example 5

[0066] This embodiment provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0067] The invention provides conductive agent graphite and hexagonal crystal structure gas phase nano β-Al2O3, wherein the particle size D50 of the β-Al2O3 is 50 nm. The conductive agent and β-Al2O3 are first mixed at a mass ratio of 6:4. The first mixing is carried out by ball milling for 2 hours to obtain the modified conductive agent.

[0068] Then, the modified conductive agent, the positive electrode active material manganese dioxide, and the binder polyvinylidene fluoride are mixed and granulated according to a mass ratio of 9:88:3, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0069] Example 6

[0070] This embodiment provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0071] The invention provides conductive agent graphite and hexagonal crystal structure gas phase nano β-Al2O3, wherein the particle size D50 of the β-Al2O3 is 20 nm. The conductive agent and β-Al2O3 are first mixed at a mass ratio of 6:4. The first mixing is carried out by ball milling for 2 hours to obtain the modified conductive agent.

[0072] Then, the modified conductive agent, the positive electrode active material manganese dioxide, and the binder polyvinylidene fluoride are mixed and granulated according to a mass ratio of 9:88:3, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0073] Example 7

[0074] This embodiment provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0075] The invention provides conductive agent graphite and hexagonal crystal structure gas phase nano β-Al2O3, wherein the particle size D50 of the β-Al2O3 is 75 nm. The conductive agent and β-Al2O3 are first mixed at a mass ratio of 6:4. The first mixing is carried out by ball milling for 2 hours to obtain the modified conductive agent.

[0076] Then, the modified conductive agent, the positive electrode active material manganese dioxide, and the binder polyvinylidene fluoride are mixed and granulated according to a mass ratio of 9:88:3, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0077] Example 8

[0078] This embodiment provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0079] The invention provides conductive agent graphite and hexagonal crystal structure gas phase nano β-Al2O3, wherein the particle size D50 of the β-Al2O3 is 100 nm. The conductive agent and β-Al2O3 are first mixed at a mass ratio of 6:4. The first mixing is carried out by ball milling for 2 hours to obtain the modified conductive agent.

[0080] Then, the modified conductive agent, the positive electrode active material manganese dioxide, and the binder polyvinylidene fluoride are mixed and granulated according to a mass ratio of 9:88:3, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0081] Example 9

[0082] This embodiment provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0083] The invention provides conductive agent graphite and hexagonal crystal structure gas phase nano β-Al2O3, wherein the particle size D50 of the β-Al2O3 is 130 nm. The conductive agent and β-Al2O3 are first mixed at a mass ratio of 6:4. The first mixing is carried out by ball milling for 2 hours to obtain the modified conductive agent.

[0084] Then, the modified conductive agent, the positive electrode active material manganese dioxide, and the binder polyvinylidene fluoride are mixed and granulated according to a mass ratio of 9:88:3, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0085] Comparative Example 1

[0086] This comparative example provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0087] The conductive agent is provided as graphite and α-Al2O3, wherein the particle size D50 of the α-Al2O3 is 50 nm. The conductive agent and α-Al2O3 are first mixed at a mass ratio of 7:2. The first mixing is performed by ball milling in a ball mill for 2 hours to obtain the modified conductive agent.

[0088] Then, the modified conductive agent, the positive electrode active material manganese dioxide, and the binder polyvinylidene fluoride are mixed and granulated according to a mass ratio of 9:88:3, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0089] Comparative Example 2

[0090] This comparative example provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0091] Graphite, a conductive agent, is provided. Then, manganese dioxide, a positive electrode active material, and polyvinylidene fluoride, a binder, are mixed and granulated at a mass ratio of 9:88:3. The mixture is then baked at 120°C for 1 hour to obtain the positive electrode mixture.

[0092] Comparative Example 3

[0093] This comparative example provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0094] Conductive agent graphite and hexagonal crystal structure gas phase nano β-Al2O3 are provided, wherein the particle size D50 of the β-Al2O3 is 50 nm;

[0095] Then, the conductive agent, β-Al2O3, positive electrode active material manganese dioxide, and binder polyvinylidene fluoride are dry-mixed at a mass ratio of 7:2:88:3, granulated, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0096] Comparative Example 4

[0097] This comparative example provides a method for mixing the positive electrode of a lithium manganese primary battery, the method comprising:

[0098] The cathode active material is manganese dioxide and hexagonal crystalline nano-β-Al2O3, wherein the particle size (D50) of the β-Al2O3 is 50 nm. The manganese dioxide and β-Al2O3 are first mixed at a mass ratio of 88:2, and the first mixing is carried out by ball milling for 2 hours to obtain a mixture.

[0099] Then, the mixture, conductive agent graphite, and binder polyvinylidene fluoride are taken in a mass ratio of 90:7:3, mixed and granulated, and then baked at 120℃ for 1 hour to obtain the positive electrode mixture.

[0100] The positive electrode mixtures obtained in the examples and comparative examples are compressed and molded with a current collector in a molding die to obtain a positive electrode sheet; a negative electrode sheet, a separator, and an electrolyte are provided; the negative electrode sheet is a lithium metal sheet; the separator is a PE separator; the electrolyte includes a lithium salt and a non-aqueous solvent; the lithium salt is LiFSI, and the non-aqueous solvent is ethylene carbonate; the obtained positive electrode sheets are assembled with the above-mentioned negative electrode sheet, separator, electrolyte, and other components to form batteries to obtain various lithium manganese primary batteries.

[0101] Electrochemical performance tests were conducted on all obtained lithium-manganese primary batteries. Batteries assembled in Examples 1-9 and Comparative Examples 1-6 were pre-discharged using a constant current discharge of 5mA for 4 hours. After discharge, they were aged at 60℃ for 48 hours. After aging, the batteries were cooled at room temperature for 6 hours before electrochemical performance testing. The basic battery performance (OCV, open-circuit voltage) and IR (internal resistance) were tested at 25℃, and the initial capacity was tested at 25℃ using a constant resistance discharge of 10kΩ with a cutoff voltage of 2.0V. Specific results are shown in Table 1 below.

[0102] Table 1

[0103]

[0104] As shown in Table 1, compared with the battery of Comparative Example 1, the battery of Comparative Example 1 has increased internal resistance and decreased initial capacity. This can be attributed to the fact that α-Al2O3 has no conductivity, and its addition leads to a deterioration in the internal electron transport effect of the battery. Compared with the battery of Comparative Example 4, the battery of Example 1 has decreased internal resistance and significantly increased initial capacity, indicating that mixing β-Al2O3 into the conductive agent can make the conductive agent more uniformly dispersed in the positive electrode system, improve conductivity, and thus improve battery performance.

[0105] Compared with Comparative Examples 3-4, the battery performance results of Example 1 show that the dispersion method is also related. Mixing all materials at the same time or mixing β-Al2O3 with the active material manganese dioxide first did not improve the dispersion effect of the conductive agent in the system.

[0106] Compared with Examples 2-5, Example 1 shows a slight increase in internal resistance and a decrease in initial capacity, indicating that the optimal ratio of conductive agent to β-Al2O3 is 7:2. However, the initial capacity of Examples 2-5 also decreased very little and was improved compared with Comparative Example 4, so the application of other ratios is not a problem.

[0107] Compared with Examples 6-9, the battery performance shows that the optimal D50 particle size of β-Al2O3 is between 50nm and 100nm. This may be because if the particle size of β-Al2O3 is too large or too small, the compounding effect of the conductive agent will be poor. β-Al2O3 cannot be uniformly dispersed and adsorbed to fill the gaps and surrounding areas of the conductive agent, resulting in poor dispersion.

[0108] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0109] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0110] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for mixing the positive electrode material for a lithium manganese primary battery, characterized in that, The positive electrode mixing method includes: The conductive agent is first mixed with β-Al2O3 to obtain a modified conductive agent; then the modified conductive agent is second mixed with a positive electrode active material and a binder, wherein the positive electrode active material includes manganese dioxide, to obtain a positive electrode mixture.

2. The method for mixing the positive electrode of a lithium manganese primary battery according to claim 1, characterized in that, The β-Al2O3 comprises gaseous nano-β-Al2O3 with a hexagonal crystal structure and a purity ≥98%. Preferably, the particle size (D50) of the β-Al2O3 is 50 nm to 100 nm. Preferably, the specific surface area of ​​the β-Al₂O₃ is 80 m². 2 / g~100m 2 / g.

3. The method for mixing the positive electrode of a lithium manganese primary battery according to claim 1 or 2, characterized in that, Based on the total mass of the conductive agent, β-Al2O3, positive electrode active material, and binder being 100%, the mass of β-Al2O3 accounts for 1% to 3%. And / or, the mass percentage of the positive electrode active material is 85%~91%; And / or, the conductive agent accounts for 6% to 8% of the total mass; And / or, the adhesive accounts for 2% to 4% of the total mass.

4. The method for mixing the positive electrode of a lithium manganese primary battery according to any one of claims 1-3, characterized in that, The conductive agent includes at least one of graphite, conductive carbon black, acetylene black, graphene, or carbon nanotubes. Preferably, the adhesive comprises at least one of polytetrafluoroethylene, styrene-butadiene rubber, ethylene-acrylic acid copolymer, or polyvinylidene fluoride and its modifiers.

5. The method for mixing the positive electrode of a lithium manganese primary battery according to any one of claims 1-4, characterized in that, The first mixing includes solid-phase mixing; Preferably, the solid-phase mixing includes ball milling; Preferably, the ball milling time is 1 hour to 3 hours.

6. The method for mixing the positive electrode of a lithium manganese primary battery according to any one of claims 1-5, characterized in that, The second mixing process includes a semi-dry process; Preferably, the semi-dry process includes mixing and granulating the modified conductive agent, positive electrode active material and binder, and then baking them to obtain a positive electrode mixture. Preferably, the baking temperature is 110℃~130℃ and the baking time is 0.5h~2h.

7. A positive electrode mixture, characterized in that, It is obtained using the positive electrode mixing method according to any one of claims 1-6.

8. A positive electrode plate, characterized in that, It is prepared using the positive electrode mixture according to claim 7.

9. A lithium-manganese primary battery, characterized in that, It contains the positive electrode sheet as described in claim 8.

10. An electrical device, characterized in that, It contains the lithium manganese primary battery as described in claim 9.

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