Positive electrode structure of lithium-manganese button cell, preparation method and preparation equipment

Abstract

The invention discloses a positive electrode structure of a lithium-manganese button cell, a preparation method and preparation equipment. The preparation method comprises the following steps: step A, performing primary compression on positive electrode powder to prepare a prefabricated positive electrode cake; b, the strip-shaped stainless steel wire net is cut to form a stainless steel wire net wafer; c, stamping the outer edge of the stainless steel wire mesh wafer to form a flaring-shaped stainless steel wire mesh bowl, wherein the depth of the flaring-shaped stainless steel wire mesh bowl is smaller than the height of the prefabricated positive electrode cake; d, buckling the flaring-shaped stainless steel wire mesh bowl on the prefabricated positive electrode cake to form a to-be-pressed body; and E, placing the body to be pressed on the lower die in the direction that the flaring-shaped stainless steel wire mesh bowl is arranged on the upper portion and the prefabricated positive electrode cake is arranged on the lower die, and stamping the body to be pressed downwards through the upper die which is distributed in a concentric circle mode and is of a concave-convex structure alternately, so that the positive electrode structure of the lithium-manganese button cell is formed, the manufacturing method is simple, and the stability of the positive electrode structure and the discharging performance of the cell can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium manganese button cells, and in particular to a positive electrode structure, a preparation method and a preparation device of a lithium manganese button cell. Background Art

[0002] In the field of lithium manganese button batteries, the design of the current collector or positive electrode inner ring plays a vital role in improving battery performance, stability and extending battery life. The following is a brief introduction to the existing related technologies.

[0003] The patent document entitled Button Cell and Positive Electrode Shell thereof (CN201590436U) discloses a positive electrode collector made of a metal mesh and a cake-shaped positive electrode material in the prior art, and a technology of using a metal mesh and a positive electrode shell and welding the metal mesh to the positive electrode shell to make a positive electrode collector. Although the structural setting of the metal mesh can support the cake-shaped positive electrode material and make the structure more solid, the bottom is in contact with the positive electrode shell, and after expansion, it hinders the flow of electrolyte and affects the electrical performance. At the same time, the side edge of the positive electrode cake is prone to corner collapse during processing and subsequent discharge, which further affects the battery performance.

[0004] The patent document entitled "A current collector for lithium manganese button batteries (CN212783514U)" discloses a current collector that is cylindrical in shape as a whole, with an open upper end and four vertical plates extending upward from the bottom of the cylinder to form the side walls of the cylinder. The number of vertical plates is 3 to 6 to provide more electrolyte storage space and to be in close contact with the positive electrode shell, thereby reducing contact impedance and lowering the internal resistance of the battery. However, although it provides more electrolyte storage space, the structure may be more complicated, increasing manufacturing costs and assembly difficulty. At the same time, the increase in the number of vertical plates may affect the overall mechanical stability of the battery.

[0005] The patent document entitled "A positive electrode sheet collector for lithium manganese button battery (CN208889763U)" discloses a collector that includes a metal edge ring and a cross-shaped metal connector, which contacts the bottom of the positive electrode sheet during operation to provide good conductivity. The gap between the cross-shaped metal connector and the metal edge ring is used to store electrolyte to make up for the volatilized electrolyte and keep the electrolyte sufficient. However, this structure still has the problem of inconvenient processing, and the design of the metal connector may cause uneven distribution of the electrolyte, affecting battery performance.

[0006] In the design of lithium-manganese button batteries, balancing cost and performance is a complex optimization problem, which requires finding a suitable solution between material selection, manufacturing process, design innovation and performance requirements. The above-mentioned existing technologies are difficult to take into account both cost and performance at the same time, so it is necessary to further optimize the positive electrode of the lithium-manganese button battery. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a positive electrode structure of a lithium manganese button battery with a simple manufacturing method and capable of improving the positive electrode structure stability and battery discharge performance, and to provide a preparation method and preparation equipment for the positive electrode structure.

[0008] The technical solution adopted by the present invention to solve the above technical problem is: a method for preparing a positive electrode structure of a lithium manganese button battery: comprising the following steps:

[0009] Step A: Pressing the positive electrode powder once to prepare a prefabricated positive electrode cake;

[0010] Step B: cutting the strip-shaped stainless steel wire mesh to form a stainless steel wire mesh disc;

[0011] Step C: stamping the outer edge of the stainless steel wire mesh disc to form an expanded stainless steel wire mesh bowl, wherein the depth of the expanded stainless steel wire mesh bowl is less than the height of the prefabricated positive electrode cake;

[0012] Step D: buckling the flared stainless steel wire mesh bowl onto the prefabricated positive electrode cake to form a body to be pressed;

[0013] Step E: placing the object to be pressed on the lower mold with the flared stainless steel wire mesh bowl on top and the prefabricated positive electrode cake on the bottom, and punching the object to be pressed downward with an upper mold having concave and convex structures with concentric circles and alternating with each other, thereby forming a positive electrode structure of a lithium-manganese button battery;

[0014] The positive electrode structure of the lithium manganese button battery comprises a stainless steel wire mesh collector bowl formed by the secondary compression of the expanded stainless steel wire mesh bowl and a positive electrode cake formed by the secondary compression of the expanded stainless steel wire mesh bowl;

[0015] The stainless steel wire mesh collector bowl comprises a circular bowl bottom and an annular body;

[0016] The annular body extends around the circumference of the circular bowl bottom toward one side of the positive electrode cake and surrounds the annular outer circumference of the positive electrode cake;

[0017] The circular bowl bottom is formed by stamping into a current collecting and conducting structure with concave and convex shapes distributed in concentric circles and alternating with each other;

[0018] The current collecting and conducting structure comprises a circular central groove, an annular outer groove, and a plurality of annular protrusions and annular grooves located between the central groove and the outer groove;

[0019] The stainless steel wire mesh current collecting bowl and the positive electrode cake are pressed together so that the positive electrode cake forms downward point protrusions in the mesh holes at the bottom of the circular bowl.

[0020] The preferred technical solution adopted by the present invention to solve the above technical problems is: the diameter range of the stainless steel wire mesh collector bowl is 15.7-15.9mm, the diameter range of the central groove is 5.5-5.7mm, the width range of the outer groove is 1.1-1.3mm; each of the annular protrusions and annular grooves is of equal width.

[0021] Another technical solution adopted by the present invention to solve the above technical problem is: a positive electrode structure of a lithium manganese button battery, including a stainless steel wire mesh current collecting bowl and a positive electrode cake;

[0022] The stainless steel wire mesh collector bowl comprises a circular bowl bottom and an annular body formed by integrally stamping a stainless steel wire mesh sheet;

[0023] The annular body extends around the circumference of the circular bowl bottom toward one side of the positive electrode cake and surrounds the annular outer circumference of the positive electrode cake;

[0024] The circular bowl bottom is formed by stamping into a current collecting and conducting structure with concave and convex shapes distributed in concentric circles and alternating with each other;

[0025] The current collecting and conducting structure comprises a circular central groove, an annular outer groove, and a plurality of annular protrusions and annular grooves located between the central groove and the outer groove.

[0026] The preferred technical solution adopted by the present invention to solve the above technical problems is: the stainless steel wire mesh collector bowl and the positive electrode cake are pressed together so that the positive electrode cake forms a downward point protrusion in the mesh holes at the bottom of the circular bowl.

[0027] The preferred technical solution adopted by the present invention to solve the above technical problems is: the diameter range of the stainless steel wire mesh collector bowl is 15.7-15.9 mm, the diameter range of the central groove is 5.5-5.7 mm, and the width range of the outer groove is 1.1-1.3 mm.

[0028] The preferred technical solution adopted by the present invention to solve the above technical problem is that the annular protrusions and the annular grooves are of equal width.

[0029] Another technical solution adopted by the present invention to solve the above technical problems is: a preparation device for the positive electrode structure of a lithium-manganese button battery, which is used to prepare the positive electrode structure of a lithium-manganese button battery, including a positive electrode powder feeding module, a strip stainless steel wire mesh feeding module and an integrated positive electrode pressing module integrated on a frame; the integrated positive electrode pressing module includes a main module and an auxiliary module;

[0030] The main module includes a main forming turntable, an upper supporting turntable, a lower supporting turntable and a cake pressing mold assembly; the main forming turntable, the upper supporting turntable and the lower supporting turntable are integrated on the main rotating seat and rotate synchronously;

[0031] The cake pressing die assembly comprises a plurality of cake pressing lower dies and cake pressing upper dies; each cake pressing upper die is integrated on the upper supporting turntable, and each cake pressing lower die is integrated on the lower supporting turntable;

[0032] The main forming turntable is evenly distributed with a plurality of main station through holes in an annular shape, and each cake pressing lower die and cake pressing upper die always correspond to the corresponding main station through hole up and down;

[0033] The upper support turntable is provided with an annular support rail which rises and falls in the height direction, and the upper die of the cake pressing moves up and down along the rise and fall of the annular support rail;

[0034] The positive electrode powder feeding module is connected to the main module to form a pre-pressed cake position. In each forming cycle, a main station through hole of the main forming turntable and the corresponding cake pressing lower mold and cake pressing upper mold enter the pre-pressed cake position to realize pre-pressed cake;

[0035] The auxiliary module includes an auxiliary forming turntable, a punching die, a pre-pressing die and a forming die; the strip stainless steel wire mesh feeding module is connected to the position where the punching die is located;

[0036] The lower surface of the molding die has a circular shaping groove, and the bottom surface of the circular shaping groove has a concave-convex structure that is distributed in concentric circles and alternates with each other;

[0037] The auxiliary forming turntable is provided with a plurality of auxiliary station through holes, and one side of the auxiliary forming turntable extends between the main forming turntable and the upper supporting turntable;

[0038] The auxiliary molding turntable rotates on its own, and in each molding cycle, an auxiliary station through hole of the auxiliary molding turntable is opposite to a main station through hole of the main molding turntable to form a molding station, and the molding mold is opposite to the molding station;

[0039] The through hole of the auxiliary station preceding the forming station corresponds to the pre-pressing die, and the through hole of the auxiliary station following the forming station corresponds to the punching die.

[0040] The preferred technical solution adopted by the present invention to solve the above technical problems is: the punching die cuts the strip-shaped stainless steel wire mesh in the corresponding auxiliary station through hole to form a stainless steel wire mesh disc; the auxiliary station through hole with the stainless steel wire mesh disc is transferred to the pre-pressing die as the auxiliary forming turntable rotates;

[0041] The pre-pressing die forms an expanded stainless steel wire mesh bowl with the outer edge of the stainless steel wire mesh disc in the through hole of the corresponding auxiliary station;

[0042] The auxiliary station through hole with the expanded stainless steel wire mesh bowl is transferred to the forming station as the auxiliary forming turntable rotates and passes through the corresponding auxiliary station through hole to be buckled on the pre-pressed cake in the corresponding main station through hole;

[0043] The forming die is passed through the corresponding auxiliary station through-hole to perform shaping and stamping on the expanded stainless steel wire mesh bowl and the pre-pressed cake to form the positive electrode structure of the lithium manganese button battery.

[0044] The preferred technical solution adopted by the present invention to solve the above technical problems is: the upper surface of the annular support rail is an undulating track surface; an upper rolling wheel is provided on the outer side of the upper mold of the cake press; the upper rolling wheel is placed on the track surface and moves up and down with the undulation of the track surface.

[0045] The preferred technical solution adopted by the present invention to solve the above technical problems is: the punching die, pre-pressing die and forming die are integrated on a lower pressing plate module, and the lower pressing plate module is driven by a cylinder to move downward so that the components in different workstations can complete corresponding operations.

[0046] Compared with the prior art, the advantages of the present invention are:

[0047] First, the positive electrode cake is formed by two pressure processes, namely, pre-pressing in step A and stamping in step E, so the interior is more uniform, the strength is better, and the cake is not easily broken. The positive electrode structure after forming not only protects the positive electrode cake in subsequent production and avoids edge damage due to the protection of the annular body on the annular periphery of the positive electrode cake, but also plays a better limiting role when the positive electrode cake expands radially.

[0048] Second, the concave-convex structure design provides an expansion gap for the positive electrode cake, which is beneficial to the stability of the battery structure and the optimization of electrical performance.

[0049] Third, the setting of the concentric grooves allows a gap to be formed between the outer bottom surface of the positive electrode structure and the inner surface of the positive electrode shell, which is conducive to storing more electrolyte and improving battery performance.

[0050] Fourth, the concave-convex structure of the concentric circles makes it easier for the spaced annular protrusions to be in uniform and close contact with the positive electrode shell in the circumferential direction, avoiding the poor contact problem caused by poor flatness of a single plane and reducing the contact internal resistance; Fourth, the concave-convex structure distributed in concentric circles and alternating with each other increases the strength of the entire positive electrode structure, and it is not easy for the positive electrode structure to be damaged during the battery molding process.

[0051] Fifth, an outer groove is set on the periphery of the stainless steel wire mesh collector bowl, which can not only avoid the corners of the positive electrode shell that are difficult to control in precision, and avoid the problem of poor assembly caused by the corners of the two contacting each other, but also the outer groove is more conducive to the bottom introduction of the electrolyte.

[0052] Sixth, the stainless steel wire mesh collector bowl is directly processed and formed with stainless steel wire mesh, which not only utilizes the pore structure of the wire mesh itself to achieve the interaction of the electrolyte, but also enables the positive electrode cake to be further closely combined with the collector bowl through the pore structure and obtain expansion space. In addition, the stainless steel wire mesh is more flexible, which increases the strength of the positive electrode structure while maintaining a certain degree of flexibility, which is more conducive to the pressing of the positive electrode cake and the coordination of the positive electrode structure and the positive electrode shell.

[0053] Seventh, the equipment includes a positive electrode powder feeding module, a strip stainless steel wire mesh feeding module and an integrated positive electrode pressing module. The integrated positive electrode pressing module includes a main module for cake making and an auxiliary module for bowl making. By integrating these modules together, the pre-pressing of powder and the cutting and pre-pressing of stainless steel wire mesh can be completed on one device at the same time. Through the intersection of two rotating bodies, the prefabricated flared stainless steel wire mesh bowl is buckled on the prefabricated positive electrode cake to form a body to be pressed, and the final pressing is completed at the intersection of the modules, thereby achieving continuous production and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The present invention will be further described in detail below in conjunction with the accompanying drawings and preferred embodiments, but those skilled in the art will appreciate that these drawings are drawn only for the purpose of explaining the preferred embodiments and therefore should not be used as a limitation on the scope of the present invention. In addition, unless otherwise specified, the drawings are only schematically representing the composition or structure of the described objects and may contain exaggerated displays, and the drawings are not necessarily drawn to scale.

[0055] Figure 1 Schematic diagram of the preparation method of the positive electrode structure of a lithium manganese button battery;

[0056] Figure 2 It is a schematic diagram of the decomposition of the positive electrode structure of a lithium manganese button battery;

[0057] Figure 3 Schematic diagram of the stainless steel wire mesh collector bowl in the positive electrode structure Figure 1 ;

[0058] Figure 4 Schematic diagram of the stainless steel wire mesh collector bowl in the positive electrode structure Figure 2 ;

[0059] Figure 5 A schematic diagram of a preparation device for a positive electrode structure of a lithium manganese button battery;

[0060] Figure 6 A physical photo of the equipment for preparing the positive electrode structure of a lithium manganese button battery;

[0061] Figure 7 The second physical photo of the equipment for preparing the positive electrode structure of the lithium manganese button battery;

[0062] Figure 8 This is a workstation layout diagram of the equipment for preparing the positive electrode structure of a lithium-manganese button battery. DETAILED DESCRIPTION

[0063] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It will be appreciated by those skilled in the art that these descriptions are only illustrative and exemplary and should not be construed as limiting the scope of protection of the present invention.

[0064] It should be noted that like reference numerals denote similar items in the following drawings, and thus, once an item is defined in one drawing, it will not be further defined or explained in the subsequent drawings.

[0065] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper", "lower", "front", "back", "left", "right", "inside" and "outside" are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0066] like Figure 1 As shown, the preparation method of the positive electrode structure 6 of the lithium manganese button battery includes the following steps:

[0067] Step A: Pressing the positive electrode powder 1 once to prepare a prefabricated positive electrode cake 2.

[0068] Step B: cutting the strip-shaped stainless steel wire mesh 30 to form a stainless steel wire mesh disc 3.

[0069] Step C: stamping the outer edge of the stainless steel wire mesh disc 3 to form an expanded stainless steel wire mesh bowl 4, the depth of the expanded stainless steel wire mesh bowl 4 is less than the height of the prefabricated positive electrode cake 2.

[0070] Step D: buckle the expanded stainless steel wire mesh bowl 4 onto the prefabricated positive electrode cake 2 to form a body to be pressed 5.

[0071] Step E: The body to be pressed 5 is placed on the lower mold with the flared stainless steel wire mesh bowl 4 on top and the prefabricated positive electrode cake 2 at the bottom. The upper mold with concentric circles and alternating concave and convex structures presses the body to be pressed 5 downward to form the positive electrode structure 6 of the lithium-manganese button battery.

[0072] like Figure 1-2 As shown, the positive electrode structure 6 of the lithium manganese button battery includes a stainless steel wire mesh collector bowl 61 formed by the expanded stainless steel wire mesh bowl 4 being compressed twice and a positive electrode cake 62 formed by the expanded stainless steel wire mesh bowl 4 being compressed twice.

[0073] like Figure 2-3 As shown, the stainless steel wire mesh current collecting bowl 61 includes a circular bowl bottom 611 and an annular body 612. The annular body 612 extends toward one side of the positive electrode cake 62 around the circumference of the circular bowl bottom 611 and surrounds the annular outer circumference of the positive electrode cake 62. The circular bowl bottom 611 is formed by stamping into a current collecting and conducting structure that is distributed in concentric circles and alternately concave and convex. The current collecting and conducting structure includes a circular central groove a, an annular outer groove b, and a plurality of annular protrusions c and annular grooves d located between the central groove a and the outer groove b.

[0074] The positive electrode cake 62 is formed by two pressure processes, namely, the pre-pressing in step A and the stamping in step E, so that the interior is more uniform, the strength is better, and the cake is not easily broken. The positive electrode structure 6 after forming not only protects the positive electrode cake 62 in subsequent production and avoids edge damage, but also plays a better limiting role when the positive electrode cake 62 expands radially, because the annular body 612 protects the annular periphery of the positive electrode cake 62.

[0075] It should be noted that after forming, the stainless steel wire mesh collector bowl 61 and the positive electrode cake 62 are pressed against each other so that the positive electrode cake 62 forms a downward point convexity in the mesh of the circular bowl bottom 611. The point convexity increases the specific surface area of ​​the positive electrode cake 62 and also increases the contact area with the stainless steel wire mesh collector bowl 61, which is more conducive to electrical performance. At the same time, it also enhances the combination performance of the two and prevents the two from separating.

[0076] In this embodiment, the stainless steel wire mesh collector bowl 61 is directly processed and formed by stainless steel wire mesh, which not only utilizes the pore structure of the wire mesh itself to achieve the interaction of the electrolyte, but also enables the positive electrode cake 62 to achieve further close combination with the collector bowl through the pore structure and obtain expansion space. In addition, the stainless steel wire mesh is more flexible, which increases the strength of the positive electrode structure 6 while still maintaining a certain degree of flexibility, which is more conducive to the pressing of the positive electrode cake 62 and the cooperation between the positive electrode structure 6 and the positive electrode shell.

[0077] Compared with collector bowls made by fine processing of other conductive sheets, this preparation method has a simpler and more cost-effective molding process, does not require complicated fine processing and molding procedures, and is easy to achieve synchronous and continuous production on a single production line.

[0078] The current collecting and conducting structure with concentric circles and alternating concave and convex structures has the following advantages: first, the concave-convex structure design provides an expansion gap for the positive electrode cake 62, which is beneficial to the stability of the battery structure and the optimization of electrical performance; second, the setting of the central groove a, the outer groove b and the annular groove d forms a gap between the outer bottom surface of the positive electrode structure 6 and the inner surface of the positive electrode shell, which is beneficial to the storage of more electrolyte, enhances the tightness and conductivity between the positive electrode structure 6 and the positive electrode shell, reduces the internal resistance, and is beneficial to improve the battery performance; third, the concave-convex structure of the concentric circles makes it easier for the spaced annular protrusions c to be in close and uniform contact with the positive electrode shell in the circumferential direction, avoids the poor contact problem caused by the poor flatness of a single plane, and reduces the contact internal resistance; fourth, the concave-convex structure with concentric circles and alternating concave and convex structures increases the strength of the entire positive electrode structure 6, and it is not easy for the positive electrode structure 6 to be damaged during the battery molding process.

[0079] Preferably, an outer groove b is provided on the periphery of the stainless steel wire mesh collector bowl 61, which can not only avoid the corners of the positive electrode shell whose precision is difficult to control and avoid the problem of poor assembly caused by the abutment between the two corners, but also the outer groove b is more conducive to the bottom introduction of the electrolyte.

[0080] Preferably, if Figure 3 As shown, an inwardly buckled edge e is provided on the upper edge of the annular body 612. The edge e protects the edge of the positive electrode cake 62 and prevents the edge of the positive electrode cake 62 from being damaged.

[0081] like Figure 4 As shown, the diameter of the stainless steel wire mesh collector bowl 61 ranges from 15.7 to 15.9 mm, the diameter of the central groove a ranges from 5.5 to 5.7 mm, and the width of the outer groove b ranges from 1.1 to 1.3 mm. Each annular protrusion c and annular groove d are of equal width. This size design makes the strength of each part of the structure more uniform, which is more conducive to the stability of the entire structure.

[0082] This embodiment also provides a device for preparing the positive electrode structure 6 of a lithium-manganese button battery, which is used to prepare the positive electrode structure 6 of the lithium-manganese button battery as described above.

[0083] like Figure 5-8 As shown, the preparation equipment includes a positive electrode powder feeding module 100, a belt-shaped stainless steel wire mesh feeding module 200 and an integrated positive electrode pressing module 300 integrated on a frame. The integrated positive electrode pressing module 300 includes a main module 301 and an auxiliary module 302.

[0084] The main module 301 includes a main forming turntable 31, an upper supporting turntable 32, a lower supporting turntable 33 and a cake pressing mold assembly. The main forming turntable 31, the upper supporting turntable 32 and the lower supporting turntable 33 are integrated on the main rotating seat and rotate synchronously. The cake pressing mold assembly includes a plurality of cake pressing lower molds 34 and cake pressing upper molds 35. Each cake pressing upper mold 35 is integrated on the upper supporting turntable 32, and each cake pressing lower mold 34 is integrated on the lower supporting turntable 33.

[0085] The main forming turntable 31 is evenly distributed with a plurality of main station through holes m in a ring shape, and each cake pressing lower mold 34 and cake pressing upper mold 35 always correspond to the corresponding main station through hole m up and down. The upper support turntable 32 is provided with an annular support rail y that fluctuates up and down in the height direction, and the cake pressing upper mold 35 moves up and down along the fluctuation of the annular support rail y. The positive electrode powder feeding module 100 docks with the main module 301 and forms a pre-pressing cake position s. In each forming cycle, a main station through hole m of the main forming turntable 31 and the corresponding cake pressing lower mold 34 and cake pressing upper mold 35 enter the pre-pressing cake position s to realize pre-pressing cake.

[0086] The auxiliary module 302 includes an auxiliary forming turntable 36, a punching die 37, a pre-pressing die 38 and a forming die 39. The strip stainless steel wire mesh feeding module 200 is connected to the position where the punching die 37 is located. The lower surface of the forming die 39 has a circular shaping groove, and the bottom surface of the circular shaping groove has a concave-convex structure distributed in concentric circles and alternating with each other. The auxiliary forming turntable 36 is provided with a plurality of auxiliary station through holes n, and one side of the auxiliary forming turntable 36 extends between the main forming turntable 31 and the upper support turntable 32. The auxiliary forming turntable 36 rotates on its own, and in each forming cycle, an auxiliary station through hole n of the auxiliary forming turntable 36 and a main station through hole m of the main forming turntable 31 are opposite to form a forming station k, and the forming die 39 is opposite to the forming station k. The auxiliary station through hole n preceding the forming station corresponds to the pre-pressing die 38, and the auxiliary station through hole n next preceding corresponds to the punching die 37.

[0087] The punching die 37 cuts the strip-shaped stainless steel wire mesh in the corresponding auxiliary station through hole n to form a stainless steel wire mesh disc 3. The auxiliary station through hole n with the stainless steel wire mesh disc 3 is transferred to the pre-pressing die 38 as the auxiliary forming turntable 36 rotates. The pre-pressing die 38 forms an expanded stainless steel wire mesh bowl 4 with the outer edge of the stainless steel wire mesh disc 3 in the corresponding auxiliary station through hole n.

[0088] The auxiliary station through hole n with the expanded stainless steel wire mesh bowl 4 is transferred to the forming station as the auxiliary forming turntable 36 rotates and passes through the corresponding auxiliary station through hole n to buckle on the pre-pressed cake in the corresponding main station through hole m. The forming die 39 passes through the corresponding auxiliary station through hole n to shape and stamp the expanded stainless steel wire mesh bowl 4 and the pre-pressed cake to form the positive electrode structure 6 of the lithium manganese button battery.

[0089] Through such an integrated device, the pre-pressing of powder and the cutting and pre-pressing of stainless steel wire mesh can be completed simultaneously on one device, and through the junction of two rotating bodies, the prefabricated expanded stainless steel wire mesh bowl 4 is buckled on the prefabricated positive electrode cake 2 to form a body to be pressed 5, and the final pressing is completed at the junction of the modules, thereby realizing continuous production and improving production efficiency.

[0090] like Figure 5 As shown, the punching die 37, the pre-pressing die 38 and the forming die 39 are integrated on a lower pressing plate die set, and the lower pressing plate die set is driven by a cylinder to move downward so that the components in different workstations can complete corresponding operations.

[0091] In this embodiment, a material unloading module 500 is also provided, and a push rod assembly is provided in the lower mold 34 of the press cake. The push rod assembly is driven to move upward to discharge the contents in the main station through hole m. When the main molding turntable 31 rotates to the material unloading module 500, the ejection mechanism of the lower mold 34 of the press cake rises to eject the positive electrode structure 6 and output it to the next process through the material unloading module 500.

[0092] like Figure 5-7 As shown, the upper surface of the annular support rail y is an undulating track surface. An upper rolling wheel 41 is provided on the outer side of the upper mold 35 of the pressing cake. The upper rolling wheel 41 is placed on the track surface and moves up and down with the ups and downs of the track surface. A lower rolling wheel 42 is provided at the bottom of the lower mold 34 of the pressing cake. The lower rolling wheel 42 is placed on the lower support turntable 33 and rotates.

[0093] like Figure 5-8 As shown, the unloading module 500 is connected to the downwardly inclined cake unloading slide 43, and a plurality of powder leakage holes are provided on the cake unloading slide 43. A blocking member 44 is provided between the unloading station v and the pre-pressing cake position s, and the blocking member 44 is used to exclude the positive electrode structure from entering the pre-pressing cake position s.

[0094] like Figure 8 As shown, several subsequent stations of the pre-pressed cake station s are provided with a detection station p, and an impact detection module is provided on the upper side of the detection station p and a cake discharge mechanism is provided on the side.

[0095] When the pre-pressed cake located in the through hole m of the main station moves with the main forming turntable 31 to the lower side of the impact detection module and detects an abnormality, the ejector rod assembly in the corresponding cake pressing lower mold 34 ejects the abnormal cake, and the cake discharge mechanism discharges the ejected abnormal cake out of the main module 301.

[0096] The positive electrode structure, preparation method and preparation equipment of a lithium manganese button battery provided by the present invention are introduced. The principle and implementation mode of the present invention are described by using specific examples. The description of the above embodiments is only used to help understand the present invention and its core ideas. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. Preparation method of positive electrode structure of lithium manganese button battery: characterized in that The steps include: Step A: Pressing the positive electrode powder once to prepare a prefabricated positive electrode cake; Step B: cutting the strip-shaped stainless steel wire mesh to form a stainless steel wire mesh disc; Step C: stamping the outer edge of the stainless steel wire mesh disc to form an expanded stainless steel wire mesh bowl, wherein the depth of the expanded stainless steel wire mesh bowl is less than the height of the prefabricated positive electrode cake; Step D: buckling the flared stainless steel wire mesh bowl onto the prefabricated positive electrode cake to form a body to be pressed; Step E: placing the object to be pressed on the lower mold with the flared stainless steel wire mesh bowl on top and the prefabricated positive electrode cake on the bottom, and punching the object to be pressed downward with an upper mold having concave and convex structures with concentric circles and alternating with each other, thereby forming a positive electrode structure of a lithium-manganese button battery; The positive electrode structure of the lithium manganese button battery comprises a stainless steel wire mesh collector bowl formed by the secondary compression of the expanded stainless steel wire mesh bowl and a positive electrode cake formed by the secondary compression of the expanded stainless steel wire mesh bowl; The stainless steel wire mesh collector bowl comprises a circular bowl bottom and an annular body; The annular body extends around the circumference of the circular bowl bottom toward one side of the positive electrode cake and surrounds the annular outer circumference of the positive electrode cake; The circular bowl bottom is formed by stamping into a current collecting and conducting structure with concave and convex shapes distributed in concentric circles and alternating with each other; The current collecting and conducting structure comprises a circular central groove, an annular outer groove, and a plurality of annular protrusions and annular grooves located between the central groove and the outer groove; The stainless steel wire mesh current collecting bowl and the positive electrode cake are pressed together so that the positive electrode cake forms downward point protrusions in the mesh holes at the bottom of the circular bowl.

2. The method for preparing the positive electrode structure of the lithium manganese button battery according to claim 2 is characterized in that: The diameter of the stainless steel wire mesh collector bowl ranges from 15.7 to 15.9 mm, the diameter of the central groove ranges from 5.5 to 5.7 mm, and the width of the outer groove ranges from 1.1 to 1.3 mm; each of the annular protrusions and annular grooves has the same width.

3. The positive electrode structure of the lithium manganese button battery is characterized by: Includes stainless steel wire mesh collector bowl and positive electrode cake; The stainless steel wire mesh collector bowl comprises a circular bowl bottom and an annular body formed by integrally stamping a stainless steel wire mesh sheet; The annular body extends around the circumference of the circular bowl bottom toward one side of the positive electrode cake and surrounds the annular outer circumference of the positive electrode cake; The circular bowl bottom is formed by stamping into a current collecting and conducting structure with concave and convex shapes distributed in concentric circles and alternating with each other; The current collecting and conducting structure comprises a circular central groove, an annular outer groove, and a plurality of annular protrusions and annular grooves located between the central groove and the outer groove.

4. The positive electrode structure of the lithium manganese button cell according to claim 3, characterized in that: The stainless steel wire mesh current collecting bowl and the positive electrode cake are pressed together so that the positive electrode cake forms downward point protrusions in the mesh holes at the bottom of the circular bowl.

5. The positive electrode structure of the lithium manganese button cell according to claim 3, characterized in that: The diameter of the stainless steel wire mesh collector bowl ranges from 15.7 to 15.9 mm, the diameter of the central groove ranges from 5.5 to 5.7 mm, and the width of the outer groove ranges from 1.1 to 1.3 mm.

6. The positive electrode structure of the lithium manganese button cell according to claim 3, characterized in that: The annular protrusions and annular grooves are of equal width.

7. A device for preparing a positive electrode structure of a lithium manganese button battery, used for preparing a positive electrode structure of a lithium manganese button battery as claimed in any one of claims 3 to 6, characterized in that: It includes a positive electrode powder feeding module, a strip stainless steel wire mesh feeding module and an integrated positive electrode pressing module integrated on a frame; the integrated positive electrode pressing module includes a main module and an auxiliary module; The main module includes a main forming turntable, an upper supporting turntable, a lower supporting turntable and a cake pressing mold assembly; the main forming turntable, the upper supporting turntable and the lower supporting turntable are integrated on the main rotating seat and rotate synchronously; The cake pressing die assembly comprises a plurality of cake pressing lower dies and cake pressing upper dies; each cake pressing upper die is integrated on the upper supporting turntable, and each cake pressing lower die is integrated on the lower supporting turntable; The main forming turntable is evenly distributed with a plurality of main station through holes in an annular shape, and each cake pressing lower die and cake pressing upper die always correspond to the corresponding main station through hole up and down; The upper support turntable is provided with an annular support rail which rises and falls in the height direction, and the upper die of the cake pressing moves up and down along the rise and fall of the annular support rail; The positive electrode powder feeding module is connected to the main module to form a pre-pressed cake position. In each forming cycle, a main station through hole of the main forming turntable and the corresponding cake pressing lower mold and cake pressing upper mold enter the pre-pressed cake position to realize pre-pressed cake; The auxiliary module includes an auxiliary forming turntable, a punching die, a pre-pressing die and a forming die; the strip stainless steel wire mesh feeding module is connected to the position where the punching die is located; The lower surface of the molding die has a circular shaping groove, and the bottom surface of the circular shaping groove has a concave-convex structure that is distributed in concentric circles and alternates with each other; The auxiliary forming turntable is provided with a plurality of auxiliary station through holes, and one side of the auxiliary forming turntable extends between the main forming turntable and the upper supporting turntable; The auxiliary molding turntable rotates on its own, and in each molding cycle, an auxiliary station through hole of the auxiliary molding turntable is opposite to a main station through hole of the main molding turntable to form a molding station, and the molding mold is opposite to the molding station; The through hole of the auxiliary station preceding the forming station corresponds to the pre-pressing die, and the through hole of the auxiliary station following the forming station corresponds to the punching die.

8. The equipment for preparing the positive electrode structure of the lithium manganese button cell according to claim 7, characterized in that The punching die cuts the strip-shaped stainless steel wire mesh in the corresponding auxiliary station through hole to form a stainless steel wire mesh disc; the auxiliary station through hole with the stainless steel wire mesh disc is transferred to the pre-pressing die as the auxiliary forming turntable rotates; The pre-pressing die forms an expanded stainless steel wire mesh bowl with the outer edge of the stainless steel wire mesh disc in the through hole of the corresponding auxiliary station; The auxiliary station through hole with the expanded stainless steel wire mesh bowl is transferred to the forming station as the auxiliary forming turntable rotates and passes through the corresponding auxiliary station through hole to be buckled on the pre-pressed cake in the corresponding main station through hole; The forming die is passed through the corresponding auxiliary station through-hole to perform shaping and stamping on the expanded stainless steel wire mesh bowl and the pre-pressed cake to form the positive electrode structure of the lithium manganese button battery.

9. The equipment for preparing the positive electrode structure of the lithium manganese button cell according to claim 7, characterized in that: The upper surface of the annular support rail is an undulating track surface; an upper rolling wheel is arranged on the outer side of the upper mold for pressing the cake; the upper rolling wheel is placed on the track surface and moves up and down with the undulation of the track surface.

10. The equipment for preparing the positive electrode structure of the lithium manganese button cell according to claim 8, characterized in that: The punching die, pre-pressing die and forming die are integrated on a lower pressing plate die set, and the lower pressing plate die set is driven by a cylinder to move downward so that the components in different workstations can complete corresponding operations.

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